Ecosystem – Wikipedia

A community of living organisms together with the nonliving components of their environment

An ecosystem is a community of living organisms in conjunction with the nonliving components of their environment, interacting as a system.[2] These biotic and abiotic components are linked together through nutrient cycles and energy flows.[3] Energy enters the system through photosynthesis and is incorporated into plant tissue. By feeding on plants and on one-another, animals play an important role in the movement of matter and energy through the system. They also influence the quantity of plant and microbial biomass present. By breaking down dead organic matter, decomposers release carbon back to the atmosphere and facilitate nutrient cycling by converting nutrients stored in dead biomass back to a form that can be readily used by plants and other microbes.[4]

Ecosystems are controlled by external and internal factors. External factors such as climate, the parent material which forms the soil and topography, control the overall structure an ecosystem, but are not themselves influenced by the ecosystem.[5]

Ecosystems are dynamic entitiesthey are subject to periodic disturbances and are in the process of recovering from some past disturbance.[6] Ecosystems in similar environments that are located in different parts of the world can end up doing things very differently simply because they have different pools of species present.[5] Internal factors not only control ecosystem processes but are also controlled by them and are often subject to feedback loops.[5]

Resource inputs are generally controlled by external processes like climate and parent material. Resource availability within the ecosystem is controlled by internal factors like decomposition, root competition or shading.[5] Although humans operate within ecosystems, their cumulative effects are large enough to influence external factors like climate.[5]

Biodiversity affects ecosystem functioning, as do the processes of disturbance and succession. Ecosystems provide a variety of goods and services upon which people depend.

The term ecosystem was first used in 1935 in a publication by British ecologist Arthur Tansley.[fn 1][7] Tansley devised the concept to draw attention to the importance of transfers of materials between organisms and their environment.[8] He later refined the term, describing it as “The whole system, … including not only the organism-complex, but also the whole complex of physical factors forming what we call the environment”.[9] Tansley regarded ecosystems not simply as natural units, but as “mental isolates”.[9] Tansley later defined the spatial extent of ecosystems using the term ecotope.[10]

G. Evelyn Hutchinson, a limnologist who was a contemporary of Tansley’s, combined Charles Elton’s ideas about trophic ecology with those of Russian geochemist Vladimir Vernadsky. As a result, he suggested that mineral nutrient availability in a lake limited algal production. This would, in turn, limit the abundance of animals that feed on algae. Raymond Lindeman took these ideas further to suggest that the flow of energy through a lake was the primary driver of the ecosystem. Hutchinson’s students, brothers Howard T. Odum and Eugene P. Odum, further developed a “systems approach” to the study of ecosystems. This allowed them to study the flow of energy and material through ecological systems.[8]

Ecosystems are controlled both by external and internal factors. External factors, also called state factors, control the overall structure of an ecosystem and the way things work within it, but are not themselves influenced by the ecosystem. The most important of these is climate.[11] Climate determines the biome in which the ecosystem is embedded. Rainfall patterns and seasonal temperatures influence photosynthesis and thereby determine the amount of water and energy available to the ecosystem.[11]

Parent material determines the nature of the soil in an ecosystem, and influences the supply of mineral nutrients. Topography also controls ecosystem processes by affecting things like microclimate, soil development and the movement of water through a system. For example, ecosystems can be quite different if situated in a small depression on the landscape, versus one present on an adjacent steep hillside.[11]

Other external factors that play an important role in ecosystem functioning include time and potential biota. Similarly, the set of organisms that can potentially be present in an area can also significantly affect ecosystems. Ecosystems in similar environments that are located in different parts of the world can end up doing things very differently simply because they have different pools of species present.[11] The introduction of non-native species can cause substantial shifts in ecosystem function.[12]

Unlike external factors, internal factors in ecosystems not only control ecosystem processes but are also controlled by them. Consequently, they are often subject to feedback loops.[11] While the resource inputs are generally controlled by external processes like climate and parent material, the availability of these resources within the ecosystem is controlled by internal factors like decomposition, root competition or shading.[11] Other factors like disturbance, succession or the types of species present are also internal factors.[citation needed]

Primary production is the production of organic matter from inorganic carbon sources. This mainly occurs through photosynthesis. The energy incorporated through this process supports life on earth, while the carbon makes up much of the organic matter in living and dead biomass, soil carbon and fossil fuels. It also drives the carbon cycle, which influences global climate via the greenhouse effect.

Through the process of photosynthesis, plants capture energy from light and use it to combine carbon dioxide and water to produce carbohydrates and oxygen. The photosynthesis carried out by all the plants in an ecosystem is called the gross primary production (GPP).[13] About half of the GPP is consumed in plant respiration.[14] The remainder, that portion of GPP that is not used up by respiration, is known as the net primary production (NPP).[15] Total photosynthesis is limited by a range of environmental factors. These include the amount of light available, the amount of leaf area a plant has to capture light (shading by other plants is a major limitation of photosynthesis), rate at which carbon dioxide can be supplied to the chloroplasts to support photosynthesis, the availability of water, and the availability of suitable temperatures for carrying out photosynthesis.[13]

Energy and carbon enter ecosystems through photosynthesis, are incorporated into living tissue, transferred to other organisms that feed on the living and dead plant matter, and eventually released through respiration.[15]

The carbon and energy incorporated into plant tissues (net primary production) is either consumed by animals while the plant is alive, or it remains uneaten when the plant tissue dies and becomes detritus. In terrestrial ecosystems, roughly 90% of the net primary production ends up being broken down by decomposers. The remainder is either consumed by animals while still alive and enters the plant-based trophic system, or it is consumed after it has died, and enters the detritus-based trophic system.[citation needed]

In aquatic systems, the proportion of plant biomass that gets consumed by herbivores is much higher.[16]In trophic systems photosynthetic organisms are the primary producers. The organisms that consume their tissues are called primary consumers or secondary producersherbivores. Organisms which feed on microbes (bacteria and fungi) are termed microbivores. Animals that feed on primary consumerscarnivoresare secondary consumers. Each of these constitutes a trophic level.[16]

The sequence of consumptionfrom plant to herbivore, to carnivoreforms a food chain. Real systems are much more complex than thisorganisms will generally feed on more than one form of food, and may feed at more than one trophic level. Carnivores may capture some prey which are part of a plant-based trophic system and others that are part of a detritus-based trophic system (a bird that feeds both on herbivorous grasshoppers and earthworms, which consume detritus). Real systems, with all these complexities, form food webs rather than food chains.[16]

The carbon and nutrients in dead organic matter are broken down by a group of processes known as decomposition. This releases nutrients that can then be re-used for plant and microbial production and returns carbon dioxide to the atmosphere (or water) where it can be used for photosynthesis. In the absence of decomposition, the dead organic matter would accumulate in an ecosystem, and nutrients and atmospheric carbon dioxide would be depleted.[17] Approximately 90% of terrestrial net primary production goes directly from plant to decomposer.[16]

Decomposition processes can be separated into three categoriesleaching, fragmentation and chemical alteration of dead material. As water moves through dead organic matter, it dissolves and carries with it the water-soluble components. These are then taken up by organisms in the soil, react with mineral soil, or are transported beyond the confines of the ecosystem (and are considered lost to it).[17] Newly shed leaves and newly dead animals have high concentrations of water-soluble components and include sugars, amino acids and mineral nutrients. Leaching is more important in wet environments and much less important in dry ones.[17]

Fragmentation processes break organic material into smaller pieces, exposing new surfaces for colonization by microbes. Freshly shed leaf litter may be inaccessible due to an outer layer of cuticle or bark, and cell contents are protected by a cell wall. Newly dead animals may be covered by an exoskeleton. Fragmentation processes, which break through these protective layers, accelerate the rate of microbial decomposition.[17] Animals fragment detritus as they hunt for food, as does passage through the gut. Freeze-thaw cycles and cycles of wetting and drying also fragment dead material.[17]

The chemical alteration of the dead organic matter is primarily achieved through bacterial and fungal action. Fungal hyphae produce enzymes which can break through the tough outer structures surrounding dead plant material. They also produce enzymes which break down lignin, which allows them access to both cell contents and to the nitrogen in the lignin. Fungi can transfer carbon and nitrogen through their hyphal networks and thus, unlike bacteria, are not dependent solely on locally available resources.[17]

Decomposition rates vary among ecosystems.[18] The rate of decomposition is governed by three sets of factorsthe physical environment (temperature, moisture, and soil properties), the quantity and quality of the dead material available to decomposers, and the nature of the microbial community itself.[19] Temperature controls the rate of microbial respiration; the higher the temperature, the faster microbial decomposition occurs. It also affects soil moisture, which slows microbial growth and reduces leaching. Freeze-thaw cycles also affect decompositionfreezing temperatures kill soil microorganisms, which allows leaching to play a more important role in moving nutrients around. This can be especially important as the soil thaws in the spring, creating a pulse of nutrients which become available.[19]

Decomposition rates are low under very wet or very dry conditions. Decomposition rates are highest in wet, moist conditions with adequate levels of oxygen. Wet soils tend to become deficient in oxygen (this is especially true in wetlands), which slows microbial growth. In dry soils, decomposition slows as well, but bacteria continue to grow (albeit at a slower rate) even after soils become too dry to support plant growth.[19]

Ecosystems continually exchange energy and carbon with the wider environment. Mineral nutrients, on the other hand, are mostly cycled back and forth between plants, animals, microbes and the soil. Most nitrogen enters ecosystems through biological nitrogen fixation, is deposited through precipitation, dust, gases or is applied as fertilizer.[20]

Since most terrestrial ecosystems are nitrogen-limited, nitrogen cycling is an important control on ecosystem production.[20]

Until modern times, nitrogen fixation was the major source of nitrogen for ecosystems. Nitrogen-fixing bacteria either live symbiotically with plants or live freely in the soil. The energetic cost is high for plants which support nitrogen-fixing symbiontsas much as 25% of gross primary production when measured in controlled conditions. Many members of the legume plant family support nitrogen-fixing symbionts. Some cyanobacteria are also capable of nitrogen fixation. These are phototrophs, which carry out photosynthesis. Like other nitrogen-fixing bacteria, they can either be free-living or have symbiotic relationships with plants.[20] Other sources of nitrogen include acid deposition produced through the combustion of fossil fuels, ammonia gas which evaporates from agricultural fields which have had fertilizers applied to them, and dust.[20] Anthropogenic nitrogen inputs account for about 80% of all nitrogen fluxes in ecosystems.[20]

When plant tissues are shed or are eaten, the nitrogen in those tissues becomes available to animals and microbes. Microbial decomposition releases nitrogen compounds from dead organic matter in the soil, where plants, fungi, and bacteria compete for it. Some soil bacteria use organic nitrogen-containing compounds as a source of carbon, and release ammonium ions into the soil. This process is known as nitrogen mineralization. Others convert ammonium to nitrite and nitrate ions, a process known as nitrification. Nitric oxide and nitrous oxide are also produced during nitrification.[20] Under nitrogen-rich and oxygen-poor conditions, nitrates and nitrites are converted to nitrogen gas, a process known as denitrification.[20]

Other important nutrients include phosphorus, sulfur, calcium, potassium, magnesium and manganese.[21][18] Phosphorus enters ecosystems through weathering. As ecosystems age this supply diminishes, making phosphorus-limitation more common in older landscapes (especially in the tropics).[21] Calcium and sulfur are also produced by weathering, but acid deposition is an important source of sulfur in many ecosystems. Although magnesium and manganese are produced by weathering, exchanges between soil organic matter and living cells account for a significant portion of ecosystem fluxes. Potassium is primarily cycled between living cells and soil organic matter.[21]

Biodiversity plays an important role in ecosystem functioning.[23] The reason for this is that ecosystem processes are driven by the number of species in an ecosystem, the exact nature of each individual species, and the relative abundance organisms within these species.[24] Ecosystem processes are broad generalizations that actually take place through the actions of individual organisms. The nature of the organismsthe species, functional groups and trophic levels to which they belongdictates the sorts of actions these individuals are capable of carrying out and the relative efficiency with which they do so.[citation needed]

Ecological theory suggests that in order to coexist, species must have some level of limiting similaritythey must be different from one another in some fundamental way, otherwise one species would competitively exclude the other.[25] Despite this, the cumulative effect of additional species in an ecosystem is not linearadditional species may enhance nitrogen retention, for example, but beyond some level of species richness, additional species may have little additive effect.[24]

The addition (or loss) of species which are ecologically similar to those already present in an ecosystem tends to only have a small effect on ecosystem function. Ecologically distinct species, on the other hand, have a much larger effect. Similarly, dominant species have a large effect on ecosystem function, while rare species tend to have a small effect. Keystone species tend to have an effect on ecosystem function that is disproportionate to their abundance in an ecosystem.[24] Similarly, an ecosystem engineer is any organism that creates, significantly modifies, maintains or destroys a habitat.[citation needed]

Ecosystems are dynamic entities. They are subject to periodic disturbances and are in the process of recovering from some past disturbance.[26] When a perturbation occurs, an ecosystem responds by moving away from its initial state. The tendency of an ecosystem to remain close to its equilibrium state, despite that disturbance, is termed its resistance. On the other hand, the speed with which it returns to its initial state after disturbance is called its resilience.[26] Time plays a role in the development of soil from bare rock and the recovery of a community from disturbance.[11]

From one year to another, ecosystems experience variation in their biotic and abiotic environments. A drought, an especially cold winter and a pest outbreak all constitute short-term variability in environmental conditions. Animal populations vary from year to year, building up during resource-rich periods and crashing as they overshoot their food supply. These changes play out in changes in net primary production decomposition rates, and other ecosystem processes.[26] Longer-term changes also shape ecosystem processesthe forests of eastern North America still show legacies of cultivation which ceased 200 years ago, while methane production in eastern Siberian lakes is controlled by organic matter which accumulated during the Pleistocene.[26]

Disturbance also plays an important role in ecological processes. F. Stuart Chapin and coauthors define disturbance as “a relatively discrete event in time and space that alters the structure of populations, communities, and ecosystems and causes changes in resources availability or the physical environment”.[27] This can range from tree falls and insect outbreaks to hurricanes and wildfires to volcanic eruptions. Such disturbances can cause large changes in plant, animal and microbe populations, as well soil organic matter content.[26] Disturbance is followed by succession, a “directional change in ecosystem structure and functioning resulting from biotically driven changes in resources supply.”[27]

The frequency and severity of disturbance determine the way it affects ecosystem function. A major disturbance like a volcanic eruption or glacial advance and retreat leave behind soils that lack plants, animals or organic matter. Ecosystems that experience such disturbances undergo primary succession. A less severe disturbance like forest fires, hurricanes or cultivation result in secondary succession and a faster recovery.[26] More severe disturbance and more frequent disturbance result in longer recovery times.[26]

Ecosystem ecology studies the processes and dynamics of ecosystems, and the way the flow of matter and energy through them structures natural systems. The study of ecosystems can cover 10 orders of magnitude, from the surface layers of rocks to the surface of the planet.[28]

There is no single definition of what constitutes an ecosystem.[29] German ecologist Ernst-Detlef Schulze and coauthors defined an ecosystem as an area which is “uniform regarding the biological turnover, and contains all the fluxes above and below the ground area under consideration.” They explicitly reject Gene Likens’ use of entire river catchments as “too wide a demarcation” to be a single ecosystem, given the level of heterogeneity within such an area.[30] Other authors have suggested that an ecosystem can encompass a much larger area, even the whole planet.[31] Schulze and coauthors also rejected the idea that a single rotting log could be studied as an ecosystem because the size of the flows between the log and its surroundings are too large, relative to the proportion cycles within the log.[30] Philosopher of science Mark Sagoff considers the failure to define “the kind of object it studies” to be an obstacle to the development of theory in ecosystem ecology.[29]

Ecosystems can be studied through a variety of approachestheoretical studies, studies monitoring specific ecosystems over long periods of time, those that look at differences between ecosystems to elucidate how they work and direct manipulative experimentation.[32] Studies can be carried out at a variety of scales, ranging from whole-ecosystem studies to studying microcosms or mesocosms (simplified representations of ecosystems).[33] American ecologist Stephen R. Carpenter has argued that microcosm experiments can be “irrelevant and diversionary” if they are not carried out in conjunction with field studies done at the ecosystem scale. Microcosm experiments often fail to accurately predict ecosystem-level dynamics.[34]

The Hubbard Brook Ecosystem Study started in 1963 to study the White Mountains in New Hampshire. It was the first successful attempt to study an entire watershed as an ecosystem. The study used stream chemistry as a means of monitoring ecosystem properties, and developed a detailed biogeochemical model of the ecosystem.[35] Long-term research at the site led to the discovery of acid rain in North America in 1972. Researchers documented the depletion of soil cations (especially calcium) over the next several decades.[36]

Human activities are important in almost all ecosystems. Although humans exist and operate within ecosystems, their cumulative effects are large enough to influence external factors like climate.[11]

Ecosystems provide a variety of goods and services upon which people depend.[37] Ecosystem goods include the “tangible, material products” of ecosystem processes such as food, construction material, medicinal plants.[38] They also include less tangible items like tourism and recreation, and genes from wild plants and animals that can be used to improve domestic species.[37]

Ecosystem services, on the other hand, are generally “improvements in the condition or location of things of value”.[38] These include things like the maintenance of hydrological cycles, cleaning air and water, the maintenance of oxygen in the atmosphere, crop pollination and even things like beauty, inspiration and opportunities for research.[37] While ecosystem goods have traditionally been recognized as being the basis for things of economic value, ecosystem services tend to be taken for granted.[38]

When natural resource management is applied to whole ecosystems, rather than single species, it is termed ecosystem management.[39] Although definitions of ecosystem management abound, there is a common set of principles which underlie these definitions.[40] A fundamental principle is the long-term sustainability of the production of goods and services by the ecosystem;[40] “intergenerational sustainability [is] a precondition for management, not an afterthought”.[37]

While ecosystem management can be used as part of a plan for wilderness conservation, it can also be used in intensively managed ecosystems[37] (see, for example, agroecosystem and close to nature forestry).

As human population and per capita consumption grow, so do the resource demands imposed on ecosystems and the effects of the human ecological footprint. Natural resources are vulnerable and limited. The environmental impacts of anthropogenic actions are becoming more apparent. Problems for all ecosystems include: environmental pollution, climate change and biodiversity loss. For terrestrial ecosystems further threats include air pollution, soil degradation, and deforestation. For aquatic ecosystems threats include also unsustainable exploitation of marine resources (for example overfishing of certain species), marine pollution, microplastics pollution, water pollution, and building on coastal areas.[41]

Society is increasingly becoming aware that ecosystem services are not only limited but also that they are threatened by human activities. The need to better consider long-term ecosystem health and its role in enabling human habitation and economic activity is urgent. To help inform decision-makers, many ecosystem services are being assigned economic values, often based on the cost of replacement with anthropogenic alternatives. The ongoing challenge of prescribing economic value to nature, for example through biodiversity banking, is prompting transdisciplinary shifts in how we recognize and manage the environment, social responsibility, business opportunities, and our future as a species.[citation needed]

Originally posted here:

Ecosystem – Wikipedia

Ecosystem services – Wikipedia

Ecosystem services are the many and varied benefits that humans freely gain from the natural environment and from properly-functioning ecosystems. Such ecosystems include, for example, agroecosystems, forest ecosystems, grassland ecosystems and aquatic ecosystems. Collectively, these benefits are becoming known as ‘ecosystem services’, and are often integral to the provisioning of clean drinking water, the decomposition of wastes, and the natural pollination of crops and other plants.

While scientists and environmentalists have discussed ecosystem services implicitly for decades, the Millennium Ecosystem Assessment (MA) in the early 2000s popularized the concept.[1] There, ecosystem services are grouped into four broad categories: provisioning, such as the production of food and water; regulating, such as the control of climate and disease; supporting, such as nutrient cycles and oxygen production; and cultural, such as spiritual and recreational benefits. To help inform decision-makers, many ecosystem services are being assigned economic values.

While the notion of human dependence on Earth’s ecosystems reaches to the start of Homo sapiens’ existence, the term ‘natural capital’ was first coined by E.F. Schumacher in 1973 in his book Small is Beautiful [2]. Recognition of how ecosystems could provide complex services to humankind date back to at least Plato (c. 400 BC) who understood that deforestation could lead to soil erosion and the drying of springs.[3][pageneeded] Modern ideas of ecosystem services probably began when Marsh challenged in 1864 the idea that Earth’s natural resources are unbounded by pointing out changes in soil fertility in the Mediterranean.[4][pageneeded] It was not until the late 1940s that three key authorsHenry Fairfield Osborn, Jr,[5] William Vogt,[6] and Aldo Leopold [7]promoted recognition of human dependence on the environment.

In 1956, Paul Sears drew attention to the critical role of the ecosystem in processing wastes and recycling nutrients.[8] In 1970, Paul Ehrlich and Rosa Weigert called attention to “ecological systems” in their environmental science textbook[9] and “the most subtle and dangerous threat to man’s existence… the potential destruction, by man’s own activities, of those ecological systems upon which the very existence of the human species depends”.

The term “environmental services” was introduced in a 1970 report of the Study of Critical Environmental Problems,[10] which listed services including insect pollination, fisheries, climate regulation and flood control. In following years, variations of the term were used, but eventually ‘ecosystem services’ became the standard in scientific literature.[11]

The ecosystem services concept has continued to expand and includes socio-economic and conservation objectives, which are discussed below. A history of the concepts and terminology of ecosystem services as of 1997, can be found in Daily’s book “Nature’s Services: Societal Dependence on Natural Ecosystems”.[3]

While Gretchen Daily’s original definition distinguished between ecosystem goods and ecosystem services, Robert Costanza and colleagues’ later work and that of the Millennium Ecosystem Assessment lumped all of these together as ecosystem services.[12][13]

Per the 2006 Millennium Ecosystem Assessment (MA), ecosystem services are “the benefits people obtain from ecosystems”. The MA also delineated the four categories of ecosystem servicessupporting, provisioning, regulating and culturaldiscussed below.

By 2010, there had evolved various working definitions and descriptions of ecosystem services in the literature.[14] To prevent double counting in ecosystem services audits, for instance, The Economics of Ecosystems and Biodiversity (TEEB) replaced “Supporting Services” in the MA with “Habitat Services” and “ecosystem functions”, defined as “a subset of the interactions between ecosystem structure and processes that underpin the capacity of an ecosystem to provide goods and services”.[15]

The Millennium Ecosystem Assessment (MA) report 2005 defines Ecosystem services as benefits people obtain from ecosystems and distinguishes four categories of ecosystem services, where the so-called supporting services are regarded as the basis for the services of the other three categories.[1]

These include services such as nutrient recycling, primary production, soil formation, habitat provision and pollination.[16] These services make it possible for the ecosystems to continue providing services such as food supply, flood regulation, and water purification.

There is discussion as to how the concept of cultural ecosystem services can be operationalized. A good review of approaches in landscape aesthetics, cultural heritage, outdoor recreation, and spiritual significance to define and assess cultural values of our environment so that they fit into the ecosystem services approach is given by Daniel et al.[17] who vote for models that explicitly link ecological structures and functions with cultural values and benefits.There also is a fundamental critique of the concept of cultural ecosystem services that builds on three arguments:[18]

The following examples illustrate the relationships between humans and natural ecosystems through the services derived from them:

Understanding of ecosystem services requires a strong foundation in ecology, which describes the underlying principles and interactions of organisms and the environment. Since the scales at which these entities interact can vary from microbes to landscapes, milliseconds to millions of years, one of the greatest remaining challenges is the descriptive characterization of energy and material flow between them. For example, the area of a forest floor, the detritus upon it, the microorganisms in the soil and characteristics of the soil itself will all contribute to the abilities of that forest for providing ecosystem services like carbon sequestration, water purification, and erosion prevention to other areas within the watershed. Note that it is often possible for multiple services to be bundled together and when benefits of targeted objectives are secured, there may also be ancillary benefitsthe same forest may provide habitat for other organisms as well as human recreation, which are also ecosystem services.

The complexity of Earth’s ecosystems poses a challenge for scientists as they try to understand how relationships are interwoven among organisms, processes and their surroundings. As it relates to human ecology, a suggested research agenda [22] for the study of ecosystem services includes the following steps:

Recently, a technique has been developed to improve and standardize the evaluation of ESP functionality by quantifying the relative importance of different species in terms of their efficiency and abundance.[28] Such parameters provide indications of how species respond to changes in the environment (i.e. predators, resource availability, climate) and are useful for identifying species that are disproportionately important at providing ecosystem services. However, a critical drawback is that the technique does not account for the effects of interactions, which are often both complex and fundamental in maintaining an ecosystem and can involve species that are not readily detected as a priority. Even so, estimating the functional structure of an ecosystem and combining it with information about individual species traits can help us understand the resilience of an ecosystem amidst environmental change.

Many ecologists also believe that the provision of ecosystem services can be stabilized with biodiversity. Increasing biodiversity also benefits the variety of ecosystem services available to society. Understanding the relationship between biodiversity and an ecosystem’s stability is essential to the management of natural resources and their services.

The concept of ecological redundancy is sometimes referred to as functional compensation and assumes that more than one species performs a given role within an ecosystem.[29] More specifically, it is characterized by a particular species increasing its efficiency at providing a service when conditions are stressed in order to maintain aggregate stability in the ecosystem.[30] However, such increased dependence on a compensating species places additional stress on the ecosystem and often enhances its susceptibility to subsequent disturbance[citation needed]. The redundancy hypothesis can be summarized as “species redundancy enhances ecosystem resilience”.[31]

Another idea uses the analogy of rivets in an airplane wing to compare the exponential effect the loss of each species will have on the function of an ecosystem; this is sometimes referred to as rivet popping.[32] If only one species disappears, the loss of the ecosystem’s efficiency as a whole is relatively small; however, if several species are lost, the system essentially collapsessimilar to an airplane that lost too many rivets. The hypothesis assumes that species are relatively specialized in their roles and that their ability to compensate for one another is less than in the redundancy hypothesis. As a result, the loss of any species is critical to the performance of the ecosystem. The key difference is the rate at which the loss of species affects total ecosystem functioning.

A third explanation, known as the portfolio effect, compares biodiversity to stock holdings, where diversification minimizes the volatility of the investment, or in this case, the risk of instability of ecosystem services.[33] This is related to the idea of response diversity where a suite of species will exhibit differential responses to a given environmental perturbation. When considered together, they create a stabilizing function that preserves the integrity of a service.[34]

Several experiments have tested these hypotheses in both the field and the lab. In ECOTRON, a laboratory in the UK where many of the biotic and abiotic factors of nature can be simulated, studies have focused on the effects of earthworms and symbiotic bacteria on plant roots.[32] These laboratory experiments seem to favor the rivet hypothesis. However, a study on grasslands at Cedar Creek Reserve in Minnesota supports the redundancy hypothesis, as have many other field studies.[35]

There are questions regarding the environmental and economic values of ecosystem services.[36] Some people may be unaware of the environment in general and humanity’s interrelatedness with the natural environment, which may cause misconceptions. Although environmental awareness is rapidly improving in our contemporary world, ecosystem capital and its flow are still poorly understood, threats continue to impose, and we suffer from the so-called ‘tragedy of the commons’.[37] Many efforts to inform decision-makers of current versus future costs and benefits now involve organizing and translating scientific knowledge to economics, which articulate the consequences of our choices in comparable units of impact on human well-being.[38] An especially challenging aspect of this process is that interpreting ecological information collected from one spatial-temporal scale does not necessarily mean it can be applied at another; understanding the dynamics of ecological processes relative to ecosystem services is essential in aiding economic decisions.[39] Weighting factors such as a service’s irreplaceability or bundled services can also allocate economic value such that goal attainment becomes more efficient.

The economic valuation of ecosystem services also involves social communication and information, areas that remain particularly challenging and are the focus of many researchers.[40] In general, the idea is that although individuals make decisions for any variety of reasons, trends reveal the aggregative preferences of a society, from which the economic value of services can be inferred and assigned. The six major methods for valuing ecosystem services in monetary terms are:[41]

A peer-reviewed study published in 1997 estimated the value of the world’s ecosystem services and natural capital to be between US$1654 trillion per year, with an average of US$33 trillion per year.[42] However, Salles (2011) indicates ‘The total value of biodiversity is infinite, so having debate about what is the total value of nature is actually pointless because we can’t live without it’.

Although monetary pricing continues with respect to the valuation of ecosystem services, the challenges in policy implementation and management are significant and multitudinous. The administration of common pool resources is a subject of extensive academic pursuit.[43][44][45][46][47] From defining the problems to finding solutions that can be applied in practical and sustainable ways, there is much to overcome. Considering options must balance present and future human needs, and decision-makers must frequently work from valid but incomplete information. Existing legal policies are often considered insufficient since they typically pertain to human health-based standards that are mismatched with necessary means to protect ecosystem health and services. To improve the information available, one suggestion has involved the implementation of an Ecosystem Services Framework (ESF[48]), which integrates the biophysical and socio-economic dimensions of protecting the environment and is designed to guide institutions through multidisciplinary information and jargon, helping to direct strategic choices.

Novel and expedient methods are needed to deal with managing Earth’s ecosystem services. Local to regional collective management efforts might be considered appropriate for services like crop pollination or resources like water.[22][43] Another approach that has become increasingly popular over the last decade is the marketing of ecosystem services protection. Payment and trading of services is an emerging worldwide small-scale solution where one can acquire credits for activities such as sponsoring the protection of carbon sequestration sources or the restoration of ecosystem service providers. In some cases, banks for handling such credits have been established and conservation companies have even gone public on stock exchanges, defining an evermore parallel link with economic endeavors and opportunities for tying into social perceptions.[38] However, crucial for implementation are clearly defined land rights, which is often lacking in many developing countries.[49] In particular, many forest-rich developing countries suffering deforestation experience conflict between different forest stakeholders.[49] In addition, concerns for such global transactions include inconsistent compensation for services or resources sacrificed elsewhere and misconceived warrants for irresponsible use. Another approach has been focused on protecting ecosystem service ‘hotspots’. Recognition that the conservation of many ecosystem services aligns with more traditional conservation goals (i.e. biodiversity) has led to the suggested merging of objectives for maximizing their mutual success. This may be particularly strategic when employing networks that permit the flow of services across landscapes, and might also facilitate securing the financial means to protect services through a diversification of investors.[50][51]

For example, in recent years there has been interest in the valuation of ecosystem services provided by shellfish production and restoration.[52] A keystone species, low in the food chain, bivalve shellfish such as oysters support a complex community of species by performing a number of functions essential to the diverse array of species that surround them. There is also increasing recognition that some shellfish species may impact or control many ecological processes; so much so that they are included on the list of “ecosystem engineers”organisms that physically, biologically or chemically modify the environment around them in ways that influence the health of other organisms.[53] Many of the ecological functions and processes performed or affected by shellfish contribute to human well-being by providing a stream of valuable ecosystem services over time by filtering out particulate materials and potentially mitigating water quality issues by controlling excess nutrients in the water.

Ecosystem-based adaptation or EbA is an emerging strategy for community development and environmental management that seeks to use an ecosystem services framework to help communities adapt to the effects of climate change. The Convention on Biological Diversity currently defines Ecosystem-Based Adaptation as “the use of biodiversity and ecosystem services to help people adapt to the adverse effects of climate change”, which includes the use of “sustainable management, conservation and restoration of ecosystems, as part of an overall adaptation strategy that takes into account the multiple social, economic and cultural co-benefits for local communities”.[54]

In 2001, the Millennium Ecosystem Assessment announced that humanity’s impact on the natural world was increasing to levels never before seen, and that the degradation of the planet’s ecosystems would become a major barrier to achieving the Millennium Development Goals. In recognition of this fact, Ecosystem-Based Adaptation seeks to use the restoration of ecosystems as a stepping-stone to improving the quality of life in communities experiencing the impacts of climate change. Specifically, this involves the restoration of ecosystems that provide the community with essential services, such as the provisioning of food and water and protection from storm surges and flooding. EbA interventions typically combine elements of both climate change mitigation and adaptation to global warming to help address the community’s current and future needs.[55]

Collaborative planning between scientists, policy makers, and community members is an essential element of Ecosystem-Based Adaptation. By drawing on the expertise of outside experts and local residents alike, EbA seeks to develop unique solutions to unique problems, rather than simply replicating past projects.[54]

Ecosystem services are defined as the gains acquired by humankind from surroundings ecosystems. Four different types of ecosystem services have been distinguished by the scientific body: regulating services, provisioning services, cultural services and supporting services. An ecosystem does not necessarily offer all four types of services simultaneously; but given the intricate nature of any ecosystem, it is usually assumed that humans benefit from a combination of these services. The services offered by diverse types of ecosystems (forests, seas, coral reefs, mangroves, etc.) differ in nature and in consequence. In fact, some services directly affect the livelihood of neighboring human populations (such as fresh water, food or aesthetic value, etc.) while other services affect general environmental conditions by which humans are indirectly impacted (such as climate change, erosion regulation or natural hazard regulation, etc.).[56]

Estuarine and coastal ecosystems are both marine ecosystems. An estuary is defined as the area in which a river meets the sea or the ocean. The waters surrounding this area are predominantly salty waters or brackish waters; and the incoming river water is dynamically motioned by the tide. An estuary strip may be covered by populations of reed (or similar plants) and/or sandbanks (or similar form or land).[citation needed]

A coastal ecosystem occurs in areas where the sea or ocean waters meet the land.[citation needed]

Regulating services are the “benefits obtained from the regulation of ecosystem processes”.[57] In the case of coastal and estuarine ecosystems, these services include climate regulation, waste treatment and disease control and natural hazard regulation.

Both the biotic and abiotic ensembles of marine ecosystems play a role in climate regulation. They act as sponges when it comes to gases in the atmosphere, retaining large levels of CO2 and other greenhouse gases (methane and nitrous oxide). Marine plants also use CO2 for photosynthesis purposes and help in reducing the atmospheric CO2. The oceans and seas absorb the heat from the atmosphere and redistribute it through the means of water currents, and atmospheric processes, such as evaporation and the reflection of light allow for the cooling and warming of the overlying atmosphere. The ocean temperatures are thus imperative to the regulation of the atmospheric temperatures in any part of the world: “without the ocean, the Earth would be unbearably hot during the daylight hours and frigidly cold, if not frozen, at night”.[58]

Another service offered by marine ecosystem is the treatment of wastes, thus helping in the regulation of diseases. Wastes can be diluted and detoxified through transport across marine ecosystems; pollutants are removed from the environment and stored, buried or recycled in marine ecosystems: “Marine ecosystems break down organic waste through microbial communities that filter water, reduce/limit the effects of eutrophication, and break down toxic hydrocarbons into their basic components such as carbon dioxide, nitrogen, phosphorus, and water”.[58] The fact that waste is diluted with large volumes of water and moves with water currents leads to the regulation of diseases and the reduction of toxics in seafood.

Coastal and estuarine ecosystems act as buffer zones against natural hazards and environmental disturbances, such as floods, cyclones, tidal surges and storms. The role they play is to “[absorb] a portion of the impact and thus [lessen] its effect on the land”.[58] Wetlands, for example, and the vegetation it supports trees, root mats, etc. retain large amounts of water (surface water, snowmelt, rain, groundwater) and then slowly releases them back, decreasing the likeliness of floods.[59] Mangrove forests protect coastal shorelines from tidal erosion or erosion by currents; a process that was studied after the 1999 cyclone that hit India. Villages that were surrounded with mangrove forests encountered less damages than other villages that weren’t protected by mangroves.[60]

Provisioning services consist of all “the products obtained from ecosystems”. Marine ecosystems provide people with: wild & cultured seafood, fresh water, fiber & fuel and biochemical & genetic resources.[citation needed]

Humans consume a large number of products originating from the seas, whether as a nutritious product or for use in other sectors: “More than one billion people worldwide, or one-sixth of the global population, rely on fish as their main source of animal protein. In 2000, marine and coastal fisheries accounted for 12 per cent of world food production”.[61] Fish and other edible marine products primarily fish, shellfish, roe and seaweeds constitute for populations living along the coast the main elements of the local cultural diets, norms and traditions. A very pertinent example would be sushi, the national food of Japan, which consists mostly of different types of fish and seaweed.

Water bodies that are not highly concentrated in salts are referred to as ‘fresh water’ bodies. Fresh water may run through lakes, rivers and streams, to name a few; but it is most prominently found in the frozen state or as soil moisture or buried deep underground. Fresh water is not only important for the survival of humans, but also for the survival of all the existing species of animals, plants.[citation needed]

Marine creatures provide us with the raw materials needed for the manufacturing of clothing, building materials (lime extracted from coral reefs), ornamental items and personal-use items (luffas, art and jewelry): “The skin of marine mammals for clothing, gas deposits for energy production, lime (extracted from coral reefs) for building construction, and the timber of mangroves and coastal forests for shelter are some of the more familiar uses of marine organisms. Raw marine materials are utilized for non-essential goods as well, such as shells and corals in ornamental items”.[61] Humans have also referred to processes within marine environments for the production of renewable energy: using the power of waves or tidal power as a source of energy for the powering of a turbine, for example.[citation needed] Oceans and seas are used as sites for offshore oil and gas installations, offshore wind farms.[citation needed]

Biochemical resources are compounds extracted from marine organisms for use in medicines, pharmaceuticals, cosmetics and other biochemical products. Genetic resources are the genetic information found in marine organisms that would later on be used for animal and plant breeding and for technological advances in the biological field. These resources are either directly taken out from an organism such as fish oil as a source of omega3 , or used as a model for innovative man-made products: “such as the construction of fiber optics technology based on the properties of sponges. … Compared to terrestrial products, marine-sourced products tend to be more highly bioactive, likely due to the fact that marine organisms have to retain their potency despite being diluted in the surrounding sea-water”.[61]

Cultural services relate to the non-material world, as they benefit the benefit recreational, aesthetic, cognitive and spiritual activities, which are not easily quantifiable in monetary terms.[citation needed]

Marine environments have been used by many as an inspiration for their works of art, music, architecture, traditions… Water environments are spiritually important as a lot of people view them as a means for rejuvenation and change of perspective. Many also consider the water as being a part of their personality, especially if they have lived near it since they were kids: they associate it to fond memories and past experiences. Living near water bodies for a long time results in a certain set of water activities that become a ritual in the lives of people and of the culture in the region.[citation needed]

Sea sports are very popular among coastal populations: surfing, snorkeling, whale watching, kayaking, recreational fishing…a lot of tourists also travel to resorts close to the sea or rivers or lakes to be able to experience these activities, and relax near the water.[citation needed]

A lot can be learned from marine processes, environments and organisms that could be implemented into our daily actions and into the scientific domain. Although much is still yet to still be known about the ocean world: “by the extraordinary intricacy and complexity of the marine environment and how it is influenced by large spatial scales, time lags, and cumulative effects”.[58]

Supporting services are the services that allow for the other ecosystem services to be present. They have indirect impacts on humans that last over a long period of time. Several services can be considered as being both supporting services and regulating/cultural/provisioning services.[citation needed]

Nutrient cycling is the movement of nutrients through an ecosystem by biotic and abiotic processes.[62] The ocean is a vast storage pool for these nutrients, such as carbon, nitrogen and phosphorus. The nutrients are absorbed by the basic organisms of the marine food web and are thus transferred from one organism to the other and from one ecosystem to the other. Nutrients are recycled through the life cycle of organisms as they die and decompose, releasing the nutrients into the neighboring environment. “The service of nutrient cycling eventually impacts all other ecosystem services as all living things require a constant supply of nutrients to survive”.[58]

Biologically mediated habitats are defined as being the habitats that living marine structures offer to other organisms.[63] These need not to be designed for the sole purpose of serving as a habitat, but happen to become living quarters whilst growing naturally. For example, coral reefs and mangrove forests are home to numerous species of fish, seaweed and shellfish… The importance of these habitats is that they allow for interactions between different species, aiding the provisioning of marine goods and services. They are also very important for the growth at the early life stages of marine species (breeding and bursary spaces), as they serve as a food source and as a shelter from predators.[citation needed]

Primary production refers to the production of organic matter, i.e., chemically bound energy, through processes such as photosynthesis and chemosynthesis. The organic matter produced by primary producers forms the basis of all food webs. Further, it generates oxygen (O2), a molecule necessary to sustain animals and humans.[64][65][66][67]

Ecosystem services degradation can pose a number of risks to corporate performance as well as provide business opportunities through ecosystem restoration and enhancement. Risks and opportunities include:

Many companies are not fully aware of the extent of their dependence and impact on ecosystems and the possible ramifications. Likewise, environmental management systems and environmental due diligence tools are more suited to handle “traditional” issues of pollution and natural resource consumption. Most focus on environmental impacts, not dependence. Several newly developed tools and methodologies can help the private sector value and assess ecosystem services. These include Our Ecosystem,[68] the Corporate Ecosystem Services Review (ESR),[69] Artificial Intelligence for Ecosystem Services (ARIES),[70] the Natural Value Initiative (NVI)[71] and InVEST (Integrated Valuation of Ecosystem Services & Tradeoffs) [72]

Ecosystem services decisions require making complex choices at the intersection of ecology, technology, society and the economy. The process of making ecosystem services decisions must consider the interaction of many types of information, honor all stakeholder viewpoints, including regulatory agencies, proposal proponents, decision makers, residents, NGOs, and measure the impacts on all four parts of the intersection. These decisions are usually spatial, always multi-objective, and based on uncertain data, models, and estimates. Often it is the combination of the best science combined with the stakeholder values, estimates and opinions that drive the process.[73]

One analytical study modeled the stakeholders as agents to support water resource management decisions in the Middle Rio Grande basin of New Mexico. This study focused on modeling the stakeholder inputs across a spatial decision, but ignored uncertainty.[74] Another study used Monte Carlo methods to exercise econometric models of landowner decisions in a study of the effects of land-use change. Here the stakeholder inputs were modeled as random effects to reflect the uncertainty.[75] A third study used a Bayesian decision support system to both model the uncertainty in the scientific information Bayes Nets and to assist collecting and fusing the input from stakeholders. This study was about siting wave energy devices off the Oregon Coast, but presents a general method for managing uncertain spatial science and stakeholder information in a decision making environment.[76] Remote sensing data and analyses can be used to assess the health and extent of land cover classes that provide ecosystem services, which aids in planning, management, monitoring of stakeholders’ actions, and communication between stakeholders.[77]

In Baltic countries scientists, nature conservationists and local authorities are implementing integrated planning approach for grassland ecosystems. They are developing Integrated Planning Tool that will be based on GIS (geographic information system) technology and put online that will help for planners to choose the best grassland management solution for concrete grassland. It will look holistically at the processes in the countryside and help to find best grassland management solutions by taking into account both natural and socioeconomic factors of the particular site.

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Ecosystem services – Wikipedia

Ecosystem – Wikipedia

A community of living organisms together with the nonliving components of their environment

An ecosystem is a community of living organisms in conjunction with the nonliving components of their environment, interacting as a system.[2] These biotic and abiotic components are linked together through nutrient cycles and energy flows.[3] Energy enters the system through photosynthesis and is incorporated into plant tissue. By feeding on plants and on one-another, animals play an important role in the movement of matter and energy through the system. They also influence the quantity of plant and microbial biomass present. By breaking down dead organic matter, decomposers release carbon back to the atmosphere and facilitate nutrient cycling by converting nutrients stored in dead biomass back to a form that can be readily used by plants and other microbes.[4]

Ecosystems are controlled by external and internal factors. External factors such as climate, the parent material which forms the soil and topography, control the overall structure an ecosystem, but are not themselves influenced by the ecosystem.[5]

Ecosystems are dynamic entitiesthey are subject to periodic disturbances and are in the process of recovering from some past disturbance.[6] Ecosystems in similar environments that are located in different parts of the world can end up doing things very differently simply because they have different pools of species present.[5] Internal factors not only control ecosystem processes but are also controlled by them and are often subject to feedback loops.[5]

Resource inputs are generally controlled by external processes like climate and parent material. Resource availability within the ecosystem is controlled by internal factors like decomposition, root competition or shading.[5] Although humans operate within ecosystems, their cumulative effects are large enough to influence external factors like climate.[5]

Biodiversity affects ecosystem functioning, as do the processes of disturbance and succession. Ecosystems provide a variety of goods and services upon which people depend.

The term ecosystem was first used in 1935 in a publication by British ecologist Arthur Tansley.[fn 1][7] Tansley devised the concept to draw attention to the importance of transfers of materials between organisms and their environment.[8] He later refined the term, describing it as “The whole system, … including not only the organism-complex, but also the whole complex of physical factors forming what we call the environment”.[9] Tansley regarded ecosystems not simply as natural units, but as “mental isolates”.[9] Tansley later defined the spatial extent of ecosystems using the term ecotope.[10]

G. Evelyn Hutchinson, a limnologist who was a contemporary of Tansley’s, combined Charles Elton’s ideas about trophic ecology with those of Russian geochemist Vladimir Vernadsky. As a result, he suggested that mineral nutrient availability in a lake limited algal production. This would, in turn, limit the abundance of animals that feed on algae. Raymond Lindeman took these ideas further to suggest that the flow of energy through a lake was the primary driver of the ecosystem. Hutchinson’s students, brothers Howard T. Odum and Eugene P. Odum, further developed a “systems approach” to the study of ecosystems. This allowed them to study the flow of energy and material through ecological systems.[8]

Ecosystems are controlled both by external and internal factors. External factors, also called state factors, control the overall structure of an ecosystem and the way things work within it, but are not themselves influenced by the ecosystem. The most important of these is climate.[11] Climate determines the biome in which the ecosystem is embedded. Rainfall patterns and seasonal temperatures influence photosynthesis and thereby determine the amount of water and energy available to the ecosystem.[11]

Parent material determines the nature of the soil in an ecosystem, and influences the supply of mineral nutrients. Topography also controls ecosystem processes by affecting things like microclimate, soil development and the movement of water through a system. For example, ecosystems can be quite different if situated in a small depression on the landscape, versus one present on an adjacent steep hillside.[11]

Other external factors that play an important role in ecosystem functioning include time and potential biota. Similarly, the set of organisms that can potentially be present in an area can also significantly affect ecosystems. Ecosystems in similar environments that are located in different parts of the world can end up doing things very differently simply because they have different pools of species present.[11] The introduction of non-native species can cause substantial shifts in ecosystem function.[12]

Unlike external factors, internal factors in ecosystems not only control ecosystem processes but are also controlled by them. Consequently, they are often subject to feedback loops.[11] While the resource inputs are generally controlled by external processes like climate and parent material, the availability of these resources within the ecosystem is controlled by internal factors like decomposition, root competition or shading.[11] Other factors like disturbance, succession or the types of species present are also internal factors.[citation needed]

Primary production is the production of organic matter from inorganic carbon sources. This mainly occurs through photosynthesis. The energy incorporated through this process supports life on earth, while the carbon makes up much of the organic matter in living and dead biomass, soil carbon and fossil fuels. It also drives the carbon cycle, which influences global climate via the greenhouse effect.

Through the process of photosynthesis, plants capture energy from light and use it to combine carbon dioxide and water to produce carbohydrates and oxygen. The photosynthesis carried out by all the plants in an ecosystem is called the gross primary production (GPP).[13] About half of the GPP is consumed in plant respiration.[14] The remainder, that portion of GPP that is not used up by respiration, is known as the net primary production (NPP).[15] Total photosynthesis is limited by a range of environmental factors. These include the amount of light available, the amount of leaf area a plant has to capture light (shading by other plants is a major limitation of photosynthesis), rate at which carbon dioxide can be supplied to the chloroplasts to support photosynthesis, the availability of water, and the availability of suitable temperatures for carrying out photosynthesis.[13]

Energy and carbon enter ecosystems through photosynthesis, are incorporated into living tissue, transferred to other organisms that feed on the living and dead plant matter, and eventually released through respiration.[15]

The carbon and energy incorporated into plant tissues (net primary production) is either consumed by animals while the plant is alive, or it remains uneaten when the plant tissue dies and becomes detritus. In terrestrial ecosystems, roughly 90% of the net primary production ends up being broken down by decomposers. The remainder is either consumed by animals while still alive and enters the plant-based trophic system, or it is consumed after it has died, and enters the detritus-based trophic system.[citation needed]

In aquatic systems, the proportion of plant biomass that gets consumed by herbivores is much higher.[16]In trophic systems photosynthetic organisms are the primary producers. The organisms that consume their tissues are called primary consumers or secondary producersherbivores. Organisms which feed on microbes (bacteria and fungi) are termed microbivores. Animals that feed on primary consumerscarnivoresare secondary consumers. Each of these constitutes a trophic level.[16]

The sequence of consumptionfrom plant to herbivore, to carnivoreforms a food chain. Real systems are much more complex than thisorganisms will generally feed on more than one form of food, and may feed at more than one trophic level. Carnivores may capture some prey which are part of a plant-based trophic system and others that are part of a detritus-based trophic system (a bird that feeds both on herbivorous grasshoppers and earthworms, which consume detritus). Real systems, with all these complexities, form food webs rather than food chains.[16]

The carbon and nutrients in dead organic matter are broken down by a group of processes known as decomposition. This releases nutrients that can then be re-used for plant and microbial production and returns carbon dioxide to the atmosphere (or water) where it can be used for photosynthesis. In the absence of decomposition, the dead organic matter would accumulate in an ecosystem, and nutrients and atmospheric carbon dioxide would be depleted.[17] Approximately 90% of terrestrial net primary production goes directly from plant to decomposer.[16]

Decomposition processes can be separated into three categoriesleaching, fragmentation and chemical alteration of dead material. As water moves through dead organic matter, it dissolves and carries with it the water-soluble components. These are then taken up by organisms in the soil, react with mineral soil, or are transported beyond the confines of the ecosystem (and are considered lost to it).[17] Newly shed leaves and newly dead animals have high concentrations of water-soluble components and include sugars, amino acids and mineral nutrients. Leaching is more important in wet environments and much less important in dry ones.[17]

Fragmentation processes break organic material into smaller pieces, exposing new surfaces for colonization by microbes. Freshly shed leaf litter may be inaccessible due to an outer layer of cuticle or bark, and cell contents are protected by a cell wall. Newly dead animals may be covered by an exoskeleton. Fragmentation processes, which break through these protective layers, accelerate the rate of microbial decomposition.[17] Animals fragment detritus as they hunt for food, as does passage through the gut. Freeze-thaw cycles and cycles of wetting and drying also fragment dead material.[17]

The chemical alteration of the dead organic matter is primarily achieved through bacterial and fungal action. Fungal hyphae produce enzymes which can break through the tough outer structures surrounding dead plant material. They also produce enzymes which break down lignin, which allows them access to both cell contents and to the nitrogen in the lignin. Fungi can transfer carbon and nitrogen through their hyphal networks and thus, unlike bacteria, are not dependent solely on locally available resources.[17]

Decomposition rates vary among ecosystems.[18] The rate of decomposition is governed by three sets of factorsthe physical environment (temperature, moisture, and soil properties), the quantity and quality of the dead material available to decomposers, and the nature of the microbial community itself.[19] Temperature controls the rate of microbial respiration; the higher the temperature, the faster microbial decomposition occurs. It also affects soil moisture, which slows microbial growth and reduces leaching. Freeze-thaw cycles also affect decompositionfreezing temperatures kill soil microorganisms, which allows leaching to play a more important role in moving nutrients around. This can be especially important as the soil thaws in the spring, creating a pulse of nutrients which become available.[19]

Decomposition rates are low under very wet or very dry conditions. Decomposition rates are highest in wet, moist conditions with adequate levels of oxygen. Wet soils tend to become deficient in oxygen (this is especially true in wetlands), which slows microbial growth. In dry soils, decomposition slows as well, but bacteria continue to grow (albeit at a slower rate) even after soils become too dry to support plant growth.[19]

Ecosystems continually exchange energy and carbon with the wider environment. Mineral nutrients, on the other hand, are mostly cycled back and forth between plants, animals, microbes and the soil. Most nitrogen enters ecosystems through biological nitrogen fixation, is deposited through precipitation, dust, gases or is applied as fertilizer.[20]

Since most terrestrial ecosystems are nitrogen-limited, nitrogen cycling is an important control on ecosystem production.[20]

Until modern times, nitrogen fixation was the major source of nitrogen for ecosystems. Nitrogen-fixing bacteria either live symbiotically with plants or live freely in the soil. The energetic cost is high for plants which support nitrogen-fixing symbiontsas much as 25% of gross primary production when measured in controlled conditions. Many members of the legume plant family support nitrogen-fixing symbionts. Some cyanobacteria are also capable of nitrogen fixation. These are phototrophs, which carry out photosynthesis. Like other nitrogen-fixing bacteria, they can either be free-living or have symbiotic relationships with plants.[20] Other sources of nitrogen include acid deposition produced through the combustion of fossil fuels, ammonia gas which evaporates from agricultural fields which have had fertilizers applied to them, and dust.[20] Anthropogenic nitrogen inputs account for about 80% of all nitrogen fluxes in ecosystems.[20]

When plant tissues are shed or are eaten, the nitrogen in those tissues becomes available to animals and microbes. Microbial decomposition releases nitrogen compounds from dead organic matter in the soil, where plants, fungi, and bacteria compete for it. Some soil bacteria use organic nitrogen-containing compounds as a source of carbon, and release ammonium ions into the soil. This process is known as nitrogen mineralization. Others convert ammonium to nitrite and nitrate ions, a process known as nitrification. Nitric oxide and nitrous oxide are also produced during nitrification.[20] Under nitrogen-rich and oxygen-poor conditions, nitrates and nitrites are converted to nitrogen gas, a process known as denitrification.[20]

Other important nutrients include phosphorus, sulfur, calcium, potassium, magnesium and manganese.[21][18] Phosphorus enters ecosystems through weathering. As ecosystems age this supply diminishes, making phosphorus-limitation more common in older landscapes (especially in the tropics).[21] Calcium and sulfur are also produced by weathering, but acid deposition is an important source of sulfur in many ecosystems. Although magnesium and manganese are produced by weathering, exchanges between soil organic matter and living cells account for a significant portion of ecosystem fluxes. Potassium is primarily cycled between living cells and soil organic matter.[21]

Biodiversity plays an important role in ecosystem functioning.[23] The reason for this is that ecosystem processes are driven by the number of species in an ecosystem, the exact nature of each individual species, and the relative abundance organisms within these species.[24] Ecosystem processes are broad generalizations that actually take place through the actions of individual organisms. The nature of the organismsthe species, functional groups and trophic levels to which they belongdictates the sorts of actions these individuals are capable of carrying out and the relative efficiency with which they do so.[citation needed]

Ecological theory suggests that in order to coexist, species must have some level of limiting similaritythey must be different from one another in some fundamental way, otherwise one species would competitively exclude the other.[25] Despite this, the cumulative effect of additional species in an ecosystem is not linearadditional species may enhance nitrogen retention, for example, but beyond some level of species richness, additional species may have little additive effect.[24]

The addition (or loss) of species which are ecologically similar to those already present in an ecosystem tends to only have a small effect on ecosystem function. Ecologically distinct species, on the other hand, have a much larger effect. Similarly, dominant species have a large effect on ecosystem function, while rare species tend to have a small effect. Keystone species tend to have an effect on ecosystem function that is disproportionate to their abundance in an ecosystem.[24] Similarly, an ecosystem engineer is any organism that creates, significantly modifies, maintains or destroys a habitat.[citation needed]

Ecosystems are dynamic entities. They are subject to periodic disturbances and are in the process of recovering from some past disturbance.[26] When a perturbation occurs, an ecosystem responds by moving away from its initial state. The tendency of an ecosystem to remain close to its equilibrium state, despite that disturbance, is termed its resistance. On the other hand, the speed with which it returns to its initial state after disturbance is called its resilience.[26] Time plays a role in the development of soil from bare rock and the recovery of a community from disturbance.[11]

From one year to another, ecosystems experience variation in their biotic and abiotic environments. A drought, an especially cold winter and a pest outbreak all constitute short-term variability in environmental conditions. Animal populations vary from year to year, building up during resource-rich periods and crashing as they overshoot their food supply. These changes play out in changes in net primary production decomposition rates, and other ecosystem processes.[26] Longer-term changes also shape ecosystem processesthe forests of eastern North America still show legacies of cultivation which ceased 200 years ago, while methane production in eastern Siberian lakes is controlled by organic matter which accumulated during the Pleistocene.[26]

Disturbance also plays an important role in ecological processes. F. Stuart Chapin and coauthors define disturbance as “a relatively discrete event in time and space that alters the structure of populations, communities, and ecosystems and causes changes in resources availability or the physical environment”.[27] This can range from tree falls and insect outbreaks to hurricanes and wildfires to volcanic eruptions. Such disturbances can cause large changes in plant, animal and microbe populations, as well soil organic matter content.[26] Disturbance is followed by succession, a “directional change in ecosystem structure and functioning resulting from biotically driven changes in resources supply.”[27]

The frequency and severity of disturbance determine the way it affects ecosystem function. A major disturbance like a volcanic eruption or glacial advance and retreat leave behind soils that lack plants, animals or organic matter. Ecosystems that experience such disturbances undergo primary succession. A less severe disturbance like forest fires, hurricanes or cultivation result in secondary succession and a faster recovery.[26] More severe disturbance and more frequent disturbance result in longer recovery times.[26]

Ecosystem ecology studies the processes and dynamics of ecosystems, and the way the flow of matter and energy through them structures natural systems. The study of ecosystems can cover 10 orders of magnitude, from the surface layers of rocks to the surface of the planet.[28]

There is no single definition of what constitutes an ecosystem.[29] German ecologist Ernst-Detlef Schulze and coauthors defined an ecosystem as an area which is “uniform regarding the biological turnover, and contains all the fluxes above and below the ground area under consideration.” They explicitly reject Gene Likens’ use of entire river catchments as “too wide a demarcation” to be a single ecosystem, given the level of heterogeneity within such an area.[30] Other authors have suggested that an ecosystem can encompass a much larger area, even the whole planet.[31] Schulze and coauthors also rejected the idea that a single rotting log could be studied as an ecosystem because the size of the flows between the log and its surroundings are too large, relative to the proportion cycles within the log.[30] Philosopher of science Mark Sagoff considers the failure to define “the kind of object it studies” to be an obstacle to the development of theory in ecosystem ecology.[29]

Ecosystems can be studied through a variety of approachestheoretical studies, studies monitoring specific ecosystems over long periods of time, those that look at differences between ecosystems to elucidate how they work and direct manipulative experimentation.[32] Studies can be carried out at a variety of scales, ranging from whole-ecosystem studies to studying microcosms or mesocosms (simplified representations of ecosystems).[33] American ecologist Stephen R. Carpenter has argued that microcosm experiments can be “irrelevant and diversionary” if they are not carried out in conjunction with field studies done at the ecosystem scale. Microcosm experiments often fail to accurately predict ecosystem-level dynamics.[34]

The Hubbard Brook Ecosystem Study started in 1963 to study the White Mountains in New Hampshire. It was the first successful attempt to study an entire watershed as an ecosystem. The study used stream chemistry as a means of monitoring ecosystem properties, and developed a detailed biogeochemical model of the ecosystem.[35] Long-term research at the site led to the discovery of acid rain in North America in 1972. Researchers documented the depletion of soil cations (especially calcium) over the next several decades.[36]

Human activities are important in almost all ecosystems. Although humans exist and operate within ecosystems, their cumulative effects are large enough to influence external factors like climate.[11]

Ecosystems provide a variety of goods and services upon which people depend.[37] Ecosystem goods include the “tangible, material products” of ecosystem processes such as food, construction material, medicinal plants.[38] They also include less tangible items like tourism and recreation, and genes from wild plants and animals that can be used to improve domestic species.[37]

Ecosystem services, on the other hand, are generally “improvements in the condition or location of things of value”.[38] These include things like the maintenance of hydrological cycles, cleaning air and water, the maintenance of oxygen in the atmosphere, crop pollination and even things like beauty, inspiration and opportunities for research.[37] While ecosystem goods have traditionally been recognized as being the basis for things of economic value, ecosystem services tend to be taken for granted.[38]

When natural resource management is applied to whole ecosystems, rather than single species, it is termed ecosystem management.[39] Although definitions of ecosystem management abound, there is a common set of principles which underlie these definitions.[40] A fundamental principle is the long-term sustainability of the production of goods and services by the ecosystem;[40] “intergenerational sustainability [is] a precondition for management, not an afterthought”.[37]

While ecosystem management can be used as part of a plan for wilderness conservation, it can also be used in intensively managed ecosystems[37] (see, for example, agroecosystem and close to nature forestry).

As human population and per capita consumption grow, so do the resource demands imposed on ecosystems and the effects of the human ecological footprint. Natural resources are vulnerable and limited. The environmental impacts of anthropogenic actions are becoming more apparent. Problems for all ecosystems include: environmental pollution, climate change and biodiversity loss. For terrestrial ecosystems further threats include air pollution, soil degradation, and deforestation. For aquatic ecosystems threats include also unsustainable exploitation of marine resources (for example overfishing of certain species), marine pollution, microplastics pollution, water pollution, and building on coastal areas.[41]

Society is increasingly becoming aware that ecosystem services are not only limited but also that they are threatened by human activities. The need to better consider long-term ecosystem health and its role in enabling human habitation and economic activity is urgent. To help inform decision-makers, many ecosystem services are being assigned economic values, often based on the cost of replacement with anthropogenic alternatives. The ongoing challenge of prescribing economic value to nature, for example through biodiversity banking, is prompting transdisciplinary shifts in how we recognize and manage the environment, social responsibility, business opportunities, and our future as a species.[citation needed]

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Ecosystem – Wikipedia

ecosystem | Definition, Components, & Structure …

Ecosystem, the complex of living organisms, their physical environment, and all their interrelationships in a particular unit of space.

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conservation: The loss of ecosystems

Conservation justifiably prioritizes tropical moist forests (see tropical forest) because they hold such a large fraction of the global total of species, but a comprehensive strategy must also include the conservation of other distinctive ecosystems. For example, major habitat types such as tropical dry

A brief treatment of ecosystems follows. For full treatment, see biosphere.

An ecosystem can be categorized into its abiotic constituents, including minerals, climate, soil, water, sunlight, and all other nonliving elements, and its biotic constituents, consisting of all its living members. Linking these constituents together are two major forces: the flow of energy through the ecosystem, and the cycling of nutrients within the ecosystem.

The fundamental source of energy in almost all ecosystems is radiant energy from the Sun. The energy of sunlight is used by the ecosystems autotrophic, or self-sustaining, organisms. Consisting largely of green vegetation, these organisms are capable of photosynthesisi.e., they can use the energy of sunlight to convert carbon dioxide and water into simple, energy-rich carbohydrates. The autotrophs use the energy stored within the simple carbohydrates to produce the more complex organic compounds, such as proteins, lipids, and starches, that maintain the organisms life processes. The autotrophic segment of the ecosystem is commonly referred to as the producer level.

Organic matter generated by autotrophs directly or indirectly sustains heterotrophic organisms. Heterotrophs are the consumers of the ecosystem; they cannot make their own food. They use, rearrange, and ultimately decompose the complex organic materials built up by the autotrophs. All animals and fungi are heterotrophs, as are most bacteria and many other microorganisms.

Together, the autotrophs and heterotrophs form various trophic (feeding) levels in the ecosystem: the producer level, composed of those organisms that make their own food; the primary consumer level, composed of those organisms that feed on producers; the secondary consumer level, composed of those organisms that feed on primary consumers; and so on. The movement of organic matter and energy from the producer level through various consumer levels makes up a food chain. For example, a typical food chain in a grassland might be grass (producer) mouse (primary consumer) snake (secondary consumer) hawk (tertiary consumer). Actually, in many cases the food chains of the ecosystem overlap and interconnect, forming what ecologists call a food web. The final link in all food chains is made up of decomposers, those heterotrophs that break down dead organisms and organic wastes. A food chain in which the primary consumer feeds on living plants is called a grazing pathway; that in which the primary consumer feeds on dead plant matter is known as a detritus pathway. Both pathways are important in accounting for the energy budget of the ecosystem.

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ecosystem | Definition, Components, & Structure …

Ecosystem | Definition of Ecosystem by Merriam-Webster

1 : the complex of a community of organisms and its environment functioning as an ecological unit That influx of fresh water alters the ocean’s salinity near the seafloor, a factor that influences the makeup of the ecosystems in those places. Sid Perkins Global warming, if it proceeds as many scientists predict, threatens to undo decades of conservation work and could mean the destruction of the monarch butterfly, the edelweiss, the polar bear and innumerable other species living in fragile ecosystems, an emerging body of scientific evidence suggests. William K. Stevens

2 : something (such as a network of businesses) considered to resemble an ecological ecosystem especially because of its complex interdependent parts Newspaper layoffs have ripple effects for the entire local news ecosystem because, as the Congressional Research Service noted, television, radio and online outlets often “piggyback on reporting done by much larger newspaper staffs.” David Sirota Lots of Walmart customers are underserved by banks and other financial institutions, [Daniel] Eckert says; the company’s experiments with finance-related products and services help customers “not only save money but also have access to a financial ecosystem they were crowded out from.” Rob Walker

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Ecosystem | Definition of Ecosystem by Merriam-Webster

Ecosystem – Wikipedia

A community of living organisms together with the nonliving components of their environment

An ecosystem is a community of living organisms in conjunction with the nonliving components of their environment, interacting as a system.[2] These biotic and abiotic components are linked together through nutrient cycles and energy flows.[3] Energy enters the system through photosynthesis and is incorporated into plant tissue. By feeding on plants and on one-another, animals play an important role in the movement of matter and energy through the system. They also influence the quantity of plant and microbial biomass present. By breaking down dead organic matter, decomposers release carbon back to the atmosphere and facilitate nutrient cycling by converting nutrients stored in dead biomass back to a form that can be readily used by plants and other microbes.[4]

Ecosystems are controlled by external and internal factors. External factors such as climate, the parent material which forms the soil and topography, control the overall structure an ecosystem, but are not themselves influenced by the ecosystem.[5]

Ecosystems are dynamic entitiesthey are subject to periodic disturbances and are in the process of recovering from some past disturbance.[6] Ecosystems in similar environments that are located in different parts of the world can end up doing things very differently simply because they have different pools of species present.[5] Internal factors not only control ecosystem processes but are also controlled by them and are often subject to feedback loops.[5]

Resource inputs are generally controlled by external processes like climate and parent material. Resource availability within the ecosystem is controlled by internal factors like decomposition, root competition or shading.[5] Although humans operate within ecosystems, their cumulative effects are large enough to influence external factors like climate.[5]

Biodiversity affects ecosystem functioning, as do the processes of disturbance and succession. Ecosystems provide a variety of goods and services upon which people depend.

The term ecosystem was first used in 1935 in a publication by British ecologist Arthur Tansley.[fn 1][7] Tansley devised the concept to draw attention to the importance of transfers of materials between organisms and their environment.[8] He later refined the term, describing it as “The whole system, … including not only the organism-complex, but also the whole complex of physical factors forming what we call the environment”.[9] Tansley regarded ecosystems not simply as natural units, but as “mental isolates”.[9] Tansley later defined the spatial extent of ecosystems using the term ecotope.[10]

G. Evelyn Hutchinson, a limnologist who was a contemporary of Tansley’s, combined Charles Elton’s ideas about trophic ecology with those of Russian geochemist Vladimir Vernadsky. As a result, he suggested that mineral nutrient availability in a lake limited algal production. This would, in turn, limit the abundance of animals that feed on algae. Raymond Lindeman took these ideas further to suggest that the flow of energy through a lake was the primary driver of the ecosystem. Hutchinson’s students, brothers Howard T. Odum and Eugene P. Odum, further developed a “systems approach” to the study of ecosystems. This allowed them to study the flow of energy and material through ecological systems.[8]

Ecosystems are controlled both by external and internal factors. External factors, also called state factors, control the overall structure of an ecosystem and the way things work within it, but are not themselves influenced by the ecosystem. The most important of these is climate.[11] Climate determines the biome in which the ecosystem is embedded. Rainfall patterns and seasonal temperatures influence photosynthesis and thereby determine the amount of water and energy available to the ecosystem.[11]

Parent material determines the nature of the soil in an ecosystem, and influences the supply of mineral nutrients. Topography also controls ecosystem processes by affecting things like microclimate, soil development and the movement of water through a system. For example, ecosystems can be quite different if situated in a small depression on the landscape, versus one present on an adjacent steep hillside.[11]

Other external factors that play an important role in ecosystem functioning include time and potential biota. Similarly, the set of organisms that can potentially be present in an area can also significantly affect ecosystems. Ecosystems in similar environments that are located in different parts of the world can end up doing things very differently simply because they have different pools of species present.[11] The introduction of non-native species can cause substantial shifts in ecosystem function.[12]

Unlike external factors, internal factors in ecosystems not only control ecosystem processes but are also controlled by them. Consequently, they are often subject to feedback loops.[11] While the resource inputs are generally controlled by external processes like climate and parent material, the availability of these resources within the ecosystem is controlled by internal factors like decomposition, root competition or shading.[11] Other factors like disturbance, succession or the types of species present are also internal factors.[citation needed]

Primary production is the production of organic matter from inorganic carbon sources. This mainly occurs through photosynthesis. The energy incorporated through this process supports life on earth, while the carbon makes up much of the organic matter in living and dead biomass, soil carbon and fossil fuels. It also drives the carbon cycle, which influences global climate via the greenhouse effect.

Through the process of photosynthesis, plants capture energy from light and use it to combine carbon dioxide and water to produce carbohydrates and oxygen. The photosynthesis carried out by all the plants in an ecosystem is called the gross primary production (GPP).[13] About half of the GPP is consumed in plant respiration.[14] The remainder, that portion of GPP that is not used up by respiration, is known as the net primary production (NPP).[15] Total photosynthesis is limited by a range of environmental factors. These include the amount of light available, the amount of leaf area a plant has to capture light (shading by other plants is a major limitation of photosynthesis), rate at which carbon dioxide can be supplied to the chloroplasts to support photosynthesis, the availability of water, and the availability of suitable temperatures for carrying out photosynthesis.[13]

Energy and carbon enter ecosystems through photosynthesis, are incorporated into living tissue, transferred to other organisms that feed on the living and dead plant matter, and eventually released through respiration.[15]

The carbon and energy incorporated into plant tissues (net primary production) is either consumed by animals while the plant is alive, or it remains uneaten when the plant tissue dies and becomes detritus. In terrestrial ecosystems, roughly 90% of the net primary production ends up being broken down by decomposers. The remainder is either consumed by animals while still alive and enters the plant-based trophic system, or it is consumed after it has died, and enters the detritus-based trophic system.[citation needed]

In aquatic systems, the proportion of plant biomass that gets consumed by herbivores is much higher.[16]In trophic systems photosynthetic organisms are the primary producers. The organisms that consume their tissues are called primary consumers or secondary producersherbivores. Organisms which feed on microbes (bacteria and fungi) are termed microbivores. Animals that feed on primary consumerscarnivoresare secondary consumers. Each of these constitutes a trophic level.[16]

The sequence of consumptionfrom plant to herbivore, to carnivoreforms a food chain. Real systems are much more complex than thisorganisms will generally feed on more than one form of food, and may feed at more than one trophic level. Carnivores may capture some prey which are part of a plant-based trophic system and others that are part of a detritus-based trophic system (a bird that feeds both on herbivorous grasshoppers and earthworms, which consume detritus). Real systems, with all these complexities, form food webs rather than food chains.[16]

The carbon and nutrients in dead organic matter are broken down by a group of processes known as decomposition. This releases nutrients that can then be re-used for plant and microbial production and returns carbon dioxide to the atmosphere (or water) where it can be used for photosynthesis. In the absence of decomposition, the dead organic matter would accumulate in an ecosystem, and nutrients and atmospheric carbon dioxide would be depleted.[17] Approximately 90% of terrestrial net primary production goes directly from plant to decomposer.[16]

Decomposition processes can be separated into three categoriesleaching, fragmentation and chemical alteration of dead material. As water moves through dead organic matter, it dissolves and carries with it the water-soluble components. These are then taken up by organisms in the soil, react with mineral soil, or are transported beyond the confines of the ecosystem (and are considered lost to it).[17] Newly shed leaves and newly dead animals have high concentrations of water-soluble components and include sugars, amino acids and mineral nutrients. Leaching is more important in wet environments and much less important in dry ones.[17]

Fragmentation processes break organic material into smaller pieces, exposing new surfaces for colonization by microbes. Freshly shed leaf litter may be inaccessible due to an outer layer of cuticle or bark, and cell contents are protected by a cell wall. Newly dead animals may be covered by an exoskeleton. Fragmentation processes, which break through these protective layers, accelerate the rate of microbial decomposition.[17] Animals fragment detritus as they hunt for food, as does passage through the gut. Freeze-thaw cycles and cycles of wetting and drying also fragment dead material.[17]

The chemical alteration of the dead organic matter is primarily achieved through bacterial and fungal action. Fungal hyphae produce enzymes which can break through the tough outer structures surrounding dead plant material. They also produce enzymes which break down lignin, which allows them access to both cell contents and to the nitrogen in the lignin. Fungi can transfer carbon and nitrogen through their hyphal networks and thus, unlike bacteria, are not dependent solely on locally available resources.[17]

Decomposition rates vary among ecosystems.[18] The rate of decomposition is governed by three sets of factorsthe physical environment (temperature, moisture, and soil properties), the quantity and quality of the dead material available to decomposers, and the nature of the microbial community itself.[19] Temperature controls the rate of microbial respiration; the higher the temperature, the faster microbial decomposition occurs. It also affects soil moisture, which slows microbial growth and reduces leaching. Freeze-thaw cycles also affect decompositionfreezing temperatures kill soil microorganisms, which allows leaching to play a more important role in moving nutrients around. This can be especially important as the soil thaws in the spring, creating a pulse of nutrients which become available.[19]

Decomposition rates are low under very wet or very dry conditions. Decomposition rates are highest in wet, moist conditions with adequate levels of oxygen. Wet soils tend to become deficient in oxygen (this is especially true in wetlands), which slows microbial growth. In dry soils, decomposition slows as well, but bacteria continue to grow (albeit at a slower rate) even after soils become too dry to support plant growth.[19]

Ecosystems continually exchange energy and carbon with the wider environment. Mineral nutrients, on the other hand, are mostly cycled back and forth between plants, animals, microbes and the soil. Most nitrogen enters ecosystems through biological nitrogen fixation, is deposited through precipitation, dust, gases or is applied as fertilizer.[20]

Since most terrestrial ecosystems are nitrogen-limited, nitrogen cycling is an important control on ecosystem production.[20]

Until modern times, nitrogen fixation was the major source of nitrogen for ecosystems. Nitrogen-fixing bacteria either live symbiotically with plants or live freely in the soil. The energetic cost is high for plants which support nitrogen-fixing symbiontsas much as 25% of gross primary production when measured in controlled conditions. Many members of the legume plant family support nitrogen-fixing symbionts. Some cyanobacteria are also capable of nitrogen fixation. These are phototrophs, which carry out photosynthesis. Like other nitrogen-fixing bacteria, they can either be free-living or have symbiotic relationships with plants.[20] Other sources of nitrogen include acid deposition produced through the combustion of fossil fuels, ammonia gas which evaporates from agricultural fields which have had fertilizers applied to them, and dust.[20] Anthropogenic nitrogen inputs account for about 80% of all nitrogen fluxes in ecosystems.[20]

When plant tissues are shed or are eaten, the nitrogen in those tissues becomes available to animals and microbes. Microbial decomposition releases nitrogen compounds from dead organic matter in the soil, where plants, fungi, and bacteria compete for it. Some soil bacteria use organic nitrogen-containing compounds as a source of carbon, and release ammonium ions into the soil. This process is known as nitrogen mineralization. Others convert ammonium to nitrite and nitrate ions, a process known as nitrification. Nitric oxide and nitrous oxide are also produced during nitrification.[20] Under nitrogen-rich and oxygen-poor conditions, nitrates and nitrites are converted to nitrogen gas, a process known as denitrification.[20]

Other important nutrients include phosphorus, sulfur, calcium, potassium, magnesium and manganese.[21][18] Phosphorus enters ecosystems through weathering. As ecosystems age this supply diminishes, making phosphorus-limitation more common in older landscapes (especially in the tropics).[21] Calcium and sulfur are also produced by weathering, but acid deposition is an important source of sulfur in many ecosystems. Although magnesium and manganese are produced by weathering, exchanges between soil organic matter and living cells account for a significant portion of ecosystem fluxes. Potassium is primarily cycled between living cells and soil organic matter.[21]

Biodiversity plays an important role in ecosystem functioning.[23] The reason for this is that ecosystem processes are driven by the number of species in an ecosystem, the exact nature of each individual species, and the relative abundance organisms within these species.[24] Ecosystem processes are broad generalizations that actually take place through the actions of individual organisms. The nature of the organismsthe species, functional groups and trophic levels to which they belongdictates the sorts of actions these individuals are capable of carrying out and the relative efficiency with which they do so.[citation needed]

Ecological theory suggests that in order to coexist, species must have some level of limiting similaritythey must be different from one another in some fundamental way, otherwise one species would competitively exclude the other.[25] Despite this, the cumulative effect of additional species in an ecosystem is not linearadditional species may enhance nitrogen retention, for example, but beyond some level of species richness, additional species may have little additive effect.[24]

The addition (or loss) of species which are ecologically similar to those already present in an ecosystem tends to only have a small effect on ecosystem function. Ecologically distinct species, on the other hand, have a much larger effect. Similarly, dominant species have a large effect on ecosystem function, while rare species tend to have a small effect. Keystone species tend to have an effect on ecosystem function that is disproportionate to their abundance in an ecosystem.[24] Similarly, an ecosystem engineer is any organism that creates, significantly modifies, maintains or destroys a habitat.[citation needed]

Ecosystems are dynamic entities. They are subject to periodic disturbances and are in the process of recovering from some past disturbance.[26] When a perturbation occurs, an ecosystem responds by moving away from its initial state. The tendency of an ecosystem to remain close to its equilibrium state, despite that disturbance, is termed its resistance. On the other hand, the speed with which it returns to its initial state after disturbance is called its resilience.[26] Time plays a role in the development of soil from bare rock and the recovery of a community from disturbance.[11]

From one year to another, ecosystems experience variation in their biotic and abiotic environments. A drought, an especially cold winter and a pest outbreak all constitute short-term variability in environmental conditions. Animal populations vary from year to year, building up during resource-rich periods and crashing as they overshoot their food supply. These changes play out in changes in net primary production decomposition rates, and other ecosystem processes.[26] Longer-term changes also shape ecosystem processesthe forests of eastern North America still show legacies of cultivation which ceased 200 years ago, while methane production in eastern Siberian lakes is controlled by organic matter which accumulated during the Pleistocene.[26]

Disturbance also plays an important role in ecological processes. F. Stuart Chapin and coauthors define disturbance as “a relatively discrete event in time and space that alters the structure of populations, communities, and ecosystems and causes changes in resources availability or the physical environment”.[27] This can range from tree falls and insect outbreaks to hurricanes and wildfires to volcanic eruptions. Such disturbances can cause large changes in plant, animal and microbe populations, as well soil organic matter content.[26] Disturbance is followed by succession, a “directional change in ecosystem structure and functioning resulting from biotically driven changes in resources supply.”[27]

The frequency and severity of disturbance determine the way it affects ecosystem function. A major disturbance like a volcanic eruption or glacial advance and retreat leave behind soils that lack plants, animals or organic matter. Ecosystems that experience such disturbances undergo primary succession. A less severe disturbance like forest fires, hurricanes or cultivation result in secondary succession and a faster recovery.[26] More severe disturbance and more frequent disturbance result in longer recovery times.[26]

Ecosystem ecology studies the processes and dynamics of ecosystems, and the way the flow of matter and energy through them structures natural systems. The study of ecosystems can cover 10 orders of magnitude, from the surface layers of rocks to the surface of the planet.[28]

There is no single definition of what constitutes an ecosystem.[29] German ecologist Ernst-Detlef Schulze and coauthors defined an ecosystem as an area which is “uniform regarding the biological turnover, and contains all the fluxes above and below the ground area under consideration.” They explicitly reject Gene Likens’ use of entire river catchments as “too wide a demarcation” to be a single ecosystem, given the level of heterogeneity within such an area.[30] Other authors have suggested that an ecosystem can encompass a much larger area, even the whole planet.[31] Schulze and coauthors also rejected the idea that a single rotting log could be studied as an ecosystem because the size of the flows between the log and its surroundings are too large, relative to the proportion cycles within the log.[30] Philosopher of science Mark Sagoff considers the failure to define “the kind of object it studies” to be an obstacle to the development of theory in ecosystem ecology.[29]

Ecosystems can be studied through a variety of approachestheoretical studies, studies monitoring specific ecosystems over long periods of time, those that look at differences between ecosystems to elucidate how they work and direct manipulative experimentation.[32] Studies can be carried out at a variety of scales, ranging from whole-ecosystem studies to studying microcosms or mesocosms (simplified representations of ecosystems).[33] American ecologist Stephen R. Carpenter has argued that microcosm experiments can be “irrelevant and diversionary” if they are not carried out in conjunction with field studies done at the ecosystem scale. Microcosm experiments often fail to accurately predict ecosystem-level dynamics.[34]

The Hubbard Brook Ecosystem Study started in 1963 to study the White Mountains in New Hampshire. It was the first successful attempt to study an entire watershed as an ecosystem. The study used stream chemistry as a means of monitoring ecosystem properties, and developed a detailed biogeochemical model of the ecosystem.[35] Long-term research at the site led to the discovery of acid rain in North America in 1972. Researchers documented the depletion of soil cations (especially calcium) over the next several decades.[36]

Human activities are important in almost all ecosystems. Although humans exist and operate within ecosystems, their cumulative effects are large enough to influence external factors like climate.[11]

Ecosystems provide a variety of goods and services upon which people depend.[37] Ecosystem goods include the “tangible, material products” of ecosystem processes such as food, construction material, medicinal plants.[38] They also include less tangible items like tourism and recreation, and genes from wild plants and animals that can be used to improve domestic species.[37]

Ecosystem services, on the other hand, are generally “improvements in the condition or location of things of value”.[38] These include things like the maintenance of hydrological cycles, cleaning air and water, the maintenance of oxygen in the atmosphere, crop pollination and even things like beauty, inspiration and opportunities for research.[37] While ecosystem goods have traditionally been recognized as being the basis for things of economic value, ecosystem services tend to be taken for granted.[38]

When natural resource management is applied to whole ecosystems, rather than single species, it is termed ecosystem management.[39] Although definitions of ecosystem management abound, there is a common set of principles which underlie these definitions.[40] A fundamental principle is the long-term sustainability of the production of goods and services by the ecosystem;[40] “intergenerational sustainability [is] a precondition for management, not an afterthought”.[37]

While ecosystem management can be used as part of a plan for wilderness conservation, it can also be used in intensively managed ecosystems[37] (see, for example, agroecosystem and close to nature forestry).

As human population and per capita consumption grow, so do the resource demands imposed on ecosystems and the effects of the human ecological footprint. Natural resources are vulnerable and limited. The environmental impacts of anthropogenic actions are becoming more apparent. Problems for all ecosystems include: environmental pollution, climate change and biodiversity loss. For terrestrial ecosystems further threats include air pollution, soil degradation, and deforestation. For aquatic ecosystems threats include also unsustainable exploitation of marine resources (for example overfishing of certain species), marine pollution, microplastics pollution, water pollution, and building on coastal areas.[41]

Society is increasingly becoming aware that ecosystem services are not only limited but also that they are threatened by human activities. The need to better consider long-term ecosystem health and its role in enabling human habitation and economic activity is urgent. To help inform decision-makers, many ecosystem services are being assigned economic values, often based on the cost of replacement with anthropogenic alternatives. The ongoing challenge of prescribing economic value to nature, for example through biodiversity banking, is prompting transdisciplinary shifts in how we recognize and manage the environment, social responsibility, business opportunities, and our future as a species.[citation needed]

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Ecosystem – Wikipedia

Ecosystem – Wikipedia

A community of living organisms together with the nonliving components of their environment

An ecosystem is a community of living organisms in conjunction with the nonliving components of their environment, interacting as a system.[2] These biotic and abiotic components are linked together through nutrient cycles and energy flows.[3] Energy enters the system through photosynthesis and is incorporated into plant tissue. By feeding on plants and on one-another, animals play an important role in the movement of matter and energy through the system. They also influence the quantity of plant and microbial biomass present. By breaking down dead organic matter, decomposers release carbon back to the atmosphere and facilitate nutrient cycling by converting nutrients stored in dead biomass back to a form that can be readily used by plants and other microbes.[4]

Ecosystems are controlled by external and internal factors. External factors such as climate, the parent material which forms the soil and topography, control the overall structure an ecosystem, but are not themselves influenced by the ecosystem.[5]

Ecosystems are dynamic entitiesthey are subject to periodic disturbances and are in the process of recovering from some past disturbance.[6] Ecosystems in similar environments that are located in different parts of the world can end up doing things very differently simply because they have different pools of species present.[5] Internal factors not only control ecosystem processes but are also controlled by them and are often subject to feedback loops.[5]

Resource inputs are generally controlled by external processes like climate and parent material. Resource availability within the ecosystem is controlled by internal factors like decomposition, root competition or shading.[5] Although humans operate within ecosystems, their cumulative effects are large enough to influence external factors like climate.[5]

Biodiversity affects ecosystem functioning, as do the processes of disturbance and succession. Ecosystems provide a variety of goods and services upon which people depend.

The term ecosystem was first used in 1935 in a publication by British ecologist Arthur Tansley.[fn 1][7] Tansley devised the concept to draw attention to the importance of transfers of materials between organisms and their environment.[8] He later refined the term, describing it as “The whole system, … including not only the organism-complex, but also the whole complex of physical factors forming what we call the environment”.[9] Tansley regarded ecosystems not simply as natural units, but as “mental isolates”.[9] Tansley later defined the spatial extent of ecosystems using the term ecotope.[10]

G. Evelyn Hutchinson, a limnologist who was a contemporary of Tansley’s, combined Charles Elton’s ideas about trophic ecology with those of Russian geochemist Vladimir Vernadsky. As a result, he suggested that mineral nutrient availability in a lake limited algal production. This would, in turn, limit the abundance of animals that feed on algae. Raymond Lindeman took these ideas further to suggest that the flow of energy through a lake was the primary driver of the ecosystem. Hutchinson’s students, brothers Howard T. Odum and Eugene P. Odum, further developed a “systems approach” to the study of ecosystems. This allowed them to study the flow of energy and material through ecological systems.[8]

Ecosystems are controlled both by external and internal factors. External factors, also called state factors, control the overall structure of an ecosystem and the way things work within it, but are not themselves influenced by the ecosystem. The most important of these is climate.[11] Climate determines the biome in which the ecosystem is embedded. Rainfall patterns and seasonal temperatures influence photosynthesis and thereby determine the amount of water and energy available to the ecosystem.[11]

Parent material determines the nature of the soil in an ecosystem, and influences the supply of mineral nutrients. Topography also controls ecosystem processes by affecting things like microclimate, soil development and the movement of water through a system. For example, ecosystems can be quite different if situated in a small depression on the landscape, versus one present on an adjacent steep hillside.[11]

Other external factors that play an important role in ecosystem functioning include time and potential biota. Similarly, the set of organisms that can potentially be present in an area can also significantly affect ecosystems. Ecosystems in similar environments that are located in different parts of the world can end up doing things very differently simply because they have different pools of species present.[11] The introduction of non-native species can cause substantial shifts in ecosystem function.[12]

Unlike external factors, internal factors in ecosystems not only control ecosystem processes but are also controlled by them. Consequently, they are often subject to feedback loops.[11] While the resource inputs are generally controlled by external processes like climate and parent material, the availability of these resources within the ecosystem is controlled by internal factors like decomposition, root competition or shading.[11] Other factors like disturbance, succession or the types of species present are also internal factors.[citation needed]

Primary production is the production of organic matter from inorganic carbon sources. This mainly occurs through photosynthesis. The energy incorporated through this process supports life on earth, while the carbon makes up much of the organic matter in living and dead biomass, soil carbon and fossil fuels. It also drives the carbon cycle, which influences global climate via the greenhouse effect.

Through the process of photosynthesis, plants capture energy from light and use it to combine carbon dioxide and water to produce carbohydrates and oxygen. The photosynthesis carried out by all the plants in an ecosystem is called the gross primary production (GPP).[13] About half of the GPP is consumed in plant respiration.[14] The remainder, that portion of GPP that is not used up by respiration, is known as the net primary production (NPP).[15] Total photosynthesis is limited by a range of environmental factors. These include the amount of light available, the amount of leaf area a plant has to capture light (shading by other plants is a major limitation of photosynthesis), rate at which carbon dioxide can be supplied to the chloroplasts to support photosynthesis, the availability of water, and the availability of suitable temperatures for carrying out photosynthesis.[13]

Energy and carbon enter ecosystems through photosynthesis, are incorporated into living tissue, transferred to other organisms that feed on the living and dead plant matter, and eventually released through respiration.[15]

The carbon and energy incorporated into plant tissues (net primary production) is either consumed by animals while the plant is alive, or it remains uneaten when the plant tissue dies and becomes detritus. In terrestrial ecosystems, roughly 90% of the net primary production ends up being broken down by decomposers. The remainder is either consumed by animals while still alive and enters the plant-based trophic system, or it is consumed after it has died, and enters the detritus-based trophic system.[citation needed]

In aquatic systems, the proportion of plant biomass that gets consumed by herbivores is much higher.[16]In trophic systems photosynthetic organisms are the primary producers. The organisms that consume their tissues are called primary consumers or secondary producersherbivores. Organisms which feed on microbes (bacteria and fungi) are termed microbivores. Animals that feed on primary consumerscarnivoresare secondary consumers. Each of these constitutes a trophic level.[16]

The sequence of consumptionfrom plant to herbivore, to carnivoreforms a food chain. Real systems are much more complex than thisorganisms will generally feed on more than one form of food, and may feed at more than one trophic level. Carnivores may capture some prey which are part of a plant-based trophic system and others that are part of a detritus-based trophic system (a bird that feeds both on herbivorous grasshoppers and earthworms, which consume detritus). Real systems, with all these complexities, form food webs rather than food chains.[16]

The carbon and nutrients in dead organic matter are broken down by a group of processes known as decomposition. This releases nutrients that can then be re-used for plant and microbial production and returns carbon dioxide to the atmosphere (or water) where it can be used for photosynthesis. In the absence of decomposition, the dead organic matter would accumulate in an ecosystem, and nutrients and atmospheric carbon dioxide would be depleted.[17] Approximately 90% of terrestrial net primary production goes directly from plant to decomposer.[16]

Decomposition processes can be separated into three categoriesleaching, fragmentation and chemical alteration of dead material. As water moves through dead organic matter, it dissolves and carries with it the water-soluble components. These are then taken up by organisms in the soil, react with mineral soil, or are transported beyond the confines of the ecosystem (and are considered lost to it).[17] Newly shed leaves and newly dead animals have high concentrations of water-soluble components and include sugars, amino acids and mineral nutrients. Leaching is more important in wet environments and much less important in dry ones.[17]

Fragmentation processes break organic material into smaller pieces, exposing new surfaces for colonization by microbes. Freshly shed leaf litter may be inaccessible due to an outer layer of cuticle or bark, and cell contents are protected by a cell wall. Newly dead animals may be covered by an exoskeleton. Fragmentation processes, which break through these protective layers, accelerate the rate of microbial decomposition.[17] Animals fragment detritus as they hunt for food, as does passage through the gut. Freeze-thaw cycles and cycles of wetting and drying also fragment dead material.[17]

The chemical alteration of the dead organic matter is primarily achieved through bacterial and fungal action. Fungal hyphae produce enzymes which can break through the tough outer structures surrounding dead plant material. They also produce enzymes which break down lignin, which allows them access to both cell contents and to the nitrogen in the lignin. Fungi can transfer carbon and nitrogen through their hyphal networks and thus, unlike bacteria, are not dependent solely on locally available resources.[17]

Decomposition rates vary among ecosystems.[18] The rate of decomposition is governed by three sets of factorsthe physical environment (temperature, moisture, and soil properties), the quantity and quality of the dead material available to decomposers, and the nature of the microbial community itself.[19] Temperature controls the rate of microbial respiration; the higher the temperature, the faster microbial decomposition occurs. It also affects soil moisture, which slows microbial growth and reduces leaching. Freeze-thaw cycles also affect decompositionfreezing temperatures kill soil microorganisms, which allows leaching to play a more important role in moving nutrients around. This can be especially important as the soil thaws in the spring, creating a pulse of nutrients which become available.[19]

Decomposition rates are low under very wet or very dry conditions. Decomposition rates are highest in wet, moist conditions with adequate levels of oxygen. Wet soils tend to become deficient in oxygen (this is especially true in wetlands), which slows microbial growth. In dry soils, decomposition slows as well, but bacteria continue to grow (albeit at a slower rate) even after soils become too dry to support plant growth.[19]

Ecosystems continually exchange energy and carbon with the wider environment. Mineral nutrients, on the other hand, are mostly cycled back and forth between plants, animals, microbes and the soil. Most nitrogen enters ecosystems through biological nitrogen fixation, is deposited through precipitation, dust, gases or is applied as fertilizer.[20]

Since most terrestrial ecosystems are nitrogen-limited, nitrogen cycling is an important control on ecosystem production.[20]

Until modern times, nitrogen fixation was the major source of nitrogen for ecosystems. Nitrogen-fixing bacteria either live symbiotically with plants or live freely in the soil. The energetic cost is high for plants which support nitrogen-fixing symbiontsas much as 25% of gross primary production when measured in controlled conditions. Many members of the legume plant family support nitrogen-fixing symbionts. Some cyanobacteria are also capable of nitrogen fixation. These are phototrophs, which carry out photosynthesis. Like other nitrogen-fixing bacteria, they can either be free-living or have symbiotic relationships with plants.[20] Other sources of nitrogen include acid deposition produced through the combustion of fossil fuels, ammonia gas which evaporates from agricultural fields which have had fertilizers applied to them, and dust.[20] Anthropogenic nitrogen inputs account for about 80% of all nitrogen fluxes in ecosystems.[20]

When plant tissues are shed or are eaten, the nitrogen in those tissues becomes available to animals and microbes. Microbial decomposition releases nitrogen compounds from dead organic matter in the soil, where plants, fungi, and bacteria compete for it. Some soil bacteria use organic nitrogen-containing compounds as a source of carbon, and release ammonium ions into the soil. This process is known as nitrogen mineralization. Others convert ammonium to nitrite and nitrate ions, a process known as nitrification. Nitric oxide and nitrous oxide are also produced during nitrification.[20] Under nitrogen-rich and oxygen-poor conditions, nitrates and nitrites are converted to nitrogen gas, a process known as denitrification.[20]

Other important nutrients include phosphorus, sulfur, calcium, potassium, magnesium and manganese.[21][18] Phosphorus enters ecosystems through weathering. As ecosystems age this supply diminishes, making phosphorus-limitation more common in older landscapes (especially in the tropics).[21] Calcium and sulfur are also produced by weathering, but acid deposition is an important source of sulfur in many ecosystems. Although magnesium and manganese are produced by weathering, exchanges between soil organic matter and living cells account for a significant portion of ecosystem fluxes. Potassium is primarily cycled between living cells and soil organic matter.[21]

Biodiversity plays an important role in ecosystem functioning.[23] The reason for this is that ecosystem processes are driven by the number of species in an ecosystem, the exact nature of each individual species, and the relative abundance organisms within these species.[24] Ecosystem processes are broad generalizations that actually take place through the actions of individual organisms. The nature of the organismsthe species, functional groups and trophic levels to which they belongdictates the sorts of actions these individuals are capable of carrying out and the relative efficiency with which they do so.[citation needed]

Ecological theory suggests that in order to coexist, species must have some level of limiting similaritythey must be different from one another in some fundamental way, otherwise one species would competitively exclude the other.[25] Despite this, the cumulative effect of additional species in an ecosystem is not linearadditional species may enhance nitrogen retention, for example, but beyond some level of species richness, additional species may have little additive effect.[24]

The addition (or loss) of species which are ecologically similar to those already present in an ecosystem tends to only have a small effect on ecosystem function. Ecologically distinct species, on the other hand, have a much larger effect. Similarly, dominant species have a large effect on ecosystem function, while rare species tend to have a small effect. Keystone species tend to have an effect on ecosystem function that is disproportionate to their abundance in an ecosystem.[24] Similarly, an ecosystem engineer is any organism that creates, significantly modifies, maintains or destroys a habitat.[citation needed]

Ecosystems are dynamic entities. They are subject to periodic disturbances and are in the process of recovering from some past disturbance.[26] When a perturbation occurs, an ecosystem responds by moving away from its initial state. The tendency of an ecosystem to remain close to its equilibrium state, despite that disturbance, is termed its resistance. On the other hand, the speed with which it returns to its initial state after disturbance is called its resilience.[26] Time plays a role in the development of soil from bare rock and the recovery of a community from disturbance.[11]

From one year to another, ecosystems experience variation in their biotic and abiotic environments. A drought, an especially cold winter and a pest outbreak all constitute short-term variability in environmental conditions. Animal populations vary from year to year, building up during resource-rich periods and crashing as they overshoot their food supply. These changes play out in changes in net primary production decomposition rates, and other ecosystem processes.[26] Longer-term changes also shape ecosystem processesthe forests of eastern North America still show legacies of cultivation which ceased 200 years ago, while methane production in eastern Siberian lakes is controlled by organic matter which accumulated during the Pleistocene.[26]

Disturbance also plays an important role in ecological processes. F. Stuart Chapin and coauthors define disturbance as “a relatively discrete event in time and space that alters the structure of populations, communities, and ecosystems and causes changes in resources availability or the physical environment”.[27] This can range from tree falls and insect outbreaks to hurricanes and wildfires to volcanic eruptions. Such disturbances can cause large changes in plant, animal and microbe populations, as well soil organic matter content.[26] Disturbance is followed by succession, a “directional change in ecosystem structure and functioning resulting from biotically driven changes in resources supply.”[27]

The frequency and severity of disturbance determine the way it affects ecosystem function. A major disturbance like a volcanic eruption or glacial advance and retreat leave behind soils that lack plants, animals or organic matter. Ecosystems that experience such disturbances undergo primary succession. A less severe disturbance like forest fires, hurricanes or cultivation result in secondary succession and a faster recovery.[26] More severe disturbance and more frequent disturbance result in longer recovery times.[26]

Ecosystem ecology studies the processes and dynamics of ecosystems, and the way the flow of matter and energy through them structures natural systems. The study of ecosystems can cover 10 orders of magnitude, from the surface layers of rocks to the surface of the planet.[28]

There is no single definition of what constitutes an ecosystem.[29] German ecologist Ernst-Detlef Schulze and coauthors defined an ecosystem as an area which is “uniform regarding the biological turnover, and contains all the fluxes above and below the ground area under consideration.” They explicitly reject Gene Likens’ use of entire river catchments as “too wide a demarcation” to be a single ecosystem, given the level of heterogeneity within such an area.[30] Other authors have suggested that an ecosystem can encompass a much larger area, even the whole planet.[31] Schulze and coauthors also rejected the idea that a single rotting log could be studied as an ecosystem because the size of the flows between the log and its surroundings are too large, relative to the proportion cycles within the log.[30] Philosopher of science Mark Sagoff considers the failure to define “the kind of object it studies” to be an obstacle to the development of theory in ecosystem ecology.[29]

Ecosystems can be studied through a variety of approachestheoretical studies, studies monitoring specific ecosystems over long periods of time, those that look at differences between ecosystems to elucidate how they work and direct manipulative experimentation.[32] Studies can be carried out at a variety of scales, ranging from whole-ecosystem studies to studying microcosms or mesocosms (simplified representations of ecosystems).[33] American ecologist Stephen R. Carpenter has argued that microcosm experiments can be “irrelevant and diversionary” if they are not carried out in conjunction with field studies done at the ecosystem scale. Microcosm experiments often fail to accurately predict ecosystem-level dynamics.[34]

The Hubbard Brook Ecosystem Study started in 1963 to study the White Mountains in New Hampshire. It was the first successful attempt to study an entire watershed as an ecosystem. The study used stream chemistry as a means of monitoring ecosystem properties, and developed a detailed biogeochemical model of the ecosystem.[35] Long-term research at the site led to the discovery of acid rain in North America in 1972. Researchers documented the depletion of soil cations (especially calcium) over the next several decades.[36]

Human activities are important in almost all ecosystems. Although humans exist and operate within ecosystems, their cumulative effects are large enough to influence external factors like climate.[11]

Ecosystems provide a variety of goods and services upon which people depend.[37] Ecosystem goods include the “tangible, material products” of ecosystem processes such as food, construction material, medicinal plants.[38] They also include less tangible items like tourism and recreation, and genes from wild plants and animals that can be used to improve domestic species.[37]

Ecosystem services, on the other hand, are generally “improvements in the condition or location of things of value”.[38] These include things like the maintenance of hydrological cycles, cleaning air and water, the maintenance of oxygen in the atmosphere, crop pollination and even things like beauty, inspiration and opportunities for research.[37] While ecosystem goods have traditionally been recognized as being the basis for things of economic value, ecosystem services tend to be taken for granted.[38]

When natural resource management is applied to whole ecosystems, rather than single species, it is termed ecosystem management.[39] Although definitions of ecosystem management abound, there is a common set of principles which underlie these definitions.[40] A fundamental principle is the long-term sustainability of the production of goods and services by the ecosystem;[40] “intergenerational sustainability [is] a precondition for management, not an afterthought”.[37]

While ecosystem management can be used as part of a plan for wilderness conservation, it can also be used in intensively managed ecosystems[37] (see, for example, agroecosystem and close to nature forestry).

As human population and per capita consumption grow, so do the resource demands imposed on ecosystems and the effects of the human ecological footprint. Natural resources are vulnerable and limited. The environmental impacts of anthropogenic actions are becoming more apparent. Problems for all ecosystems include: environmental pollution, climate change and biodiversity loss. For terrestrial ecosystems further threats include air pollution, soil degradation, and deforestation. For aquatic ecosystems threats include also unsustainable exploitation of marine resources (for example overfishing of certain species), marine pollution, microplastics pollution, water pollution, and building on coastal areas.[41]

Society is increasingly becoming aware that ecosystem services are not only limited but also that they are threatened by human activities. The need to better consider long-term ecosystem health and its role in enabling human habitation and economic activity is urgent. To help inform decision-makers, many ecosystem services are being assigned economic values, often based on the cost of replacement with anthropogenic alternatives. The ongoing challenge of prescribing economic value to nature, for example through biodiversity banking, is prompting transdisciplinary shifts in how we recognize and manage the environment, social responsibility, business opportunities, and our future as a species.[citation needed]

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Ecosystem – Wikipedia

Ecosystem services – Wikipedia

Ecosystem services are the many and varied benefits that humans freely gain from the natural environment and from properly-functioning ecosystems. Such ecosystems include, for example, agroecosystems, forest ecosystems, grassland ecosystems and aquatic ecosystems. Collectively, these benefits are becoming known as ‘ecosystem services’, and are often integral to the provisioning of clean drinking water, the decomposition of wastes, and the natural pollination of crops and other plants.

While scientists and environmentalists have discussed ecosystem services implicitly for decades, the Millennium Ecosystem Assessment (MA) in the early 2000s popularized the concept.[1] There, ecosystem services are grouped into four broad categories: provisioning, such as the production of food and water; regulating, such as the control of climate and disease; supporting, such as nutrient cycles and oxygen production; and cultural, such as spiritual and recreational benefits. To help inform decision-makers, many ecosystem services are being assigned economic values.

While the notion of human dependence on Earth’s ecosystems reaches to the start of Homo sapiens’ existence, the term ‘natural capital’ was first coined by E.F. Schumacher in 1973 in his book Small is Beautiful [2]. Recognition of how ecosystems could provide complex services to humankind date back to at least Plato (c. 400 BC) who understood that deforestation could lead to soil erosion and the drying of springs.[3][pageneeded] Modern ideas of ecosystem services probably began when Marsh challenged in 1864 the idea that Earth’s natural resources are unbounded by pointing out changes in soil fertility in the Mediterranean.[4][pageneeded] It was not until the late 1940s that three key authorsHenry Fairfield Osborn, Jr,[5] William Vogt,[6] and Aldo Leopold [7]promoted recognition of human dependence on the environment.

In 1956, Paul Sears drew attention to the critical role of the ecosystem in processing wastes and recycling nutrients.[8] In 1970, Paul Ehrlich and Rosa Weigert called attention to “ecological systems” in their environmental science textbook[9] and “the most subtle and dangerous threat to man’s existence… the potential destruction, by man’s own activities, of those ecological systems upon which the very existence of the human species depends”.

The term “environmental services” was introduced in a 1970 report of the Study of Critical Environmental Problems,[10] which listed services including insect pollination, fisheries, climate regulation and flood control. In following years, variations of the term were used, but eventually ‘ecosystem services’ became the standard in scientific literature.[11]

The ecosystem services concept has continued to expand and includes socio-economic and conservation objectives, which are discussed below. A history of the concepts and terminology of ecosystem services as of 1997, can be found in Daily’s book “Nature’s Services: Societal Dependence on Natural Ecosystems”.[3]

While Gretchen Daily’s original definition distinguished between ecosystem goods and ecosystem services, Robert Costanza and colleagues’ later work and that of the Millennium Ecosystem Assessment lumped all of these together as ecosystem services.[12][13]

Per the 2006 Millennium Ecosystem Assessment (MA), ecosystem services are “the benefits people obtain from ecosystems”. The MA also delineated the four categories of ecosystem servicessupporting, provisioning, regulating and culturaldiscussed below.

By 2010, there had evolved various working definitions and descriptions of ecosystem services in the literature.[14] To prevent double counting in ecosystem services audits, for instance, The Economics of Ecosystems and Biodiversity (TEEB) replaced “Supporting Services” in the MA with “Habitat Services” and “ecosystem functions”, defined as “a subset of the interactions between ecosystem structure and processes that underpin the capacity of an ecosystem to provide goods and services”.[15]

The Millennium Ecosystem Assessment (MA) report 2005 defines Ecosystem services as benefits people obtain from ecosystems and distinguishes four categories of ecosystem services, where the so-called supporting services are regarded as the basis for the services of the other three categories.[1]

These include services such as nutrient recycling, primary production and soil formation.[16] These services make it possible for the ecosystems to provide services such as food supply, flood regulation, and water purification.

There is discussion as to how the concept of cultural ecosystem services can be operationalized. A good review of approaches in landscape aesthetics, cultural heritage, outdoor recreation, and spiritual significance to define and assess cultural values of our environment so that they fit into the ecosystem services approach is given by Daniel et al.[17] who vote for models that explicitly link ecological structures and functions with cultural values and benefits.There also is a fundamental critique of the concept of cultural ecosystem services that builds on three arguments:[18]

The following examples illustrate the relationships between humans and natural ecosystems through the services derived from them:

Understanding of ecosystem services requires a strong foundation in ecology, which describes the underlying principles and interactions of organisms and the environment. Since the scales at which these entities interact can vary from microbes to landscapes, milliseconds to millions of years, one of the greatest remaining challenges is the descriptive characterization of energy and material flow between them. For example, the area of a forest floor, the detritus upon it, the microorganisms in the soil and characteristics of the soil itself will all contribute to the abilities of that forest for providing ecosystem services like carbon sequestration, water purification, and erosion prevention to other areas within the watershed. Note that it is often possible for multiple services to be bundled together and when benefits of targeted objectives are secured, there may also be ancillary benefitsthe same forest may provide habitat for other organisms as well as human recreation, which are also ecosystem services.

The complexity of Earth’s ecosystems poses a challenge for scientists as they try to understand how relationships are interwoven among organisms, processes and their surroundings. As it relates to human ecology, a suggested research agenda [22] for the study of ecosystem services includes the following steps:

Recently, a technique has been developed to improve and standardize the evaluation of ESP functionality by quantifying the relative importance of different species in terms of their efficiency and abundance.[28] Such parameters provide indications of how species respond to changes in the environment (i.e. predators, resource availability, climate) and are useful for identifying species that are disproportionately important at providing ecosystem services. However, a critical drawback is that the technique does not account for the effects of interactions, which are often both complex and fundamental in maintaining an ecosystem and can involve species that are not readily detected as a priority. Even so, estimating the functional structure of an ecosystem and combining it with information about individual species traits can help us understand the resilience of an ecosystem amidst environmental change.

Many ecologists also believe that the provision of ecosystem services can be stabilized with biodiversity. Increasing biodiversity also benefits the variety of ecosystem services available to society. Understanding the relationship between biodiversity and an ecosystem’s stability is essential to the management of natural resources and their services.

The concept of ecological redundancy is sometimes referred to as functional compensation and assumes that more than one species performs a given role within an ecosystem.[29] More specifically, it is characterized by a particular species increasing its efficiency at providing a service when conditions are stressed in order to maintain aggregate stability in the ecosystem.[30] However, such increased dependence on a compensating species places additional stress on the ecosystem and often enhances its susceptibility to subsequent disturbance[citation needed]. The redundancy hypothesis can be summarized as “species redundancy enhances ecosystem resilience”.[31]

Another idea uses the analogy of rivets in an airplane wing to compare the exponential effect the loss of each species will have on the function of an ecosystem; this is sometimes referred to as rivet popping.[32] If only one species disappears, the loss of the ecosystem’s efficiency as a whole is relatively small; however, if several species are lost, the system essentially collapsessimilar to an airplane that lost too many rivets. The hypothesis assumes that species are relatively specialized in their roles and that their ability to compensate for one another is less than in the redundancy hypothesis. As a result, the loss of any species is critical to the performance of the ecosystem. The key difference is the rate at which the loss of species affects total ecosystem functioning.

A third explanation, known as the portfolio effect, compares biodiversity to stock holdings, where diversification minimizes the volatility of the investment, or in this case, the risk of instability of ecosystem services.[33] This is related to the idea of response diversity where a suite of species will exhibit differential responses to a given environmental perturbation. When considered together, they create a stabilizing function that preserves the integrity of a service.[34]

Several experiments have tested these hypotheses in both the field and the lab. In ECOTRON, a laboratory in the UK where many of the biotic and abiotic factors of nature can be simulated, studies have focused on the effects of earthworms and symbiotic bacteria on plant roots.[32] These laboratory experiments seem to favor the rivet hypothesis. However, a study on grasslands at Cedar Creek Reserve in Minnesota supports the redundancy hypothesis, as have many other field studies.[35]

There are questions regarding the environmental and economic values of ecosystem services.[36] Some people may be unaware of the environment in general and humanity’s interrelatedness with the natural environment, which may cause misconceptions. Although environmental awareness is rapidly improving in our contemporary world, ecosystem capital and its flow are still poorly understood, threats continue to impose, and we suffer from the so-called ‘tragedy of the commons’.[37] Many efforts to inform decision-makers of current versus future costs and benefits now involve organizing and translating scientific knowledge to economics, which articulate the consequences of our choices in comparable units of impact on human well-being.[38] An especially challenging aspect of this process is that interpreting ecological information collected from one spatial-temporal scale does not necessarily mean it can be applied at another; understanding the dynamics of ecological processes relative to ecosystem services is essential in aiding economic decisions.[39] Weighting factors such as a service’s irreplaceability or bundled services can also allocate economic value such that goal attainment becomes more efficient.

The economic valuation of ecosystem services also involves social communication and information, areas that remain particularly challenging and are the focus of many researchers.[40] In general, the idea is that although individuals make decisions for any variety of reasons, trends reveal the aggregative preferences of a society, from which the economic value of services can be inferred and assigned. The six major methods for valuing ecosystem services in monetary terms are:[41]

A peer-reviewed study published in 1997 estimated the value of the world’s ecosystem services and natural capital to be between US$1654 trillion per year, with an average of US$33 trillion per year.[42] However, Salles (2011) indicates ‘The total value of biodiversity is infinite, so having debate about what is the total value of nature is actually pointless because we can’t live without it’.

Although monetary pricing continues with respect to the valuation of ecosystem services, the challenges in policy implementation and management are significant and multitudinous. The administration of common pool resources is a subject of extensive academic pursuit.[43][44][45][46][47] From defining the problems to finding solutions that can be applied in practical and sustainable ways, there is much to overcome. Considering options must balance present and future human needs, and decision-makers must frequently work from valid but incomplete information. Existing legal policies are often considered insufficient since they typically pertain to human health-based standards that are mismatched with necessary means to protect ecosystem health and services. To improve the information available, one suggestion has involved the implementation of an Ecosystem Services Framework (ESF[48]), which integrates the biophysical and socio-economic dimensions of protecting the environment and is designed to guide institutions through multidisciplinary information and jargon, helping to direct strategic choices.

Novel and expedient methods are needed to deal with managing Earth’s ecosystem services. Local to regional collective management efforts might be considered appropriate for services like crop pollination or resources like water.[22][43] Another approach that has become increasingly popular over the last decade is the marketing of ecosystem services protection. Payment and trading of services is an emerging worldwide small-scale solution where one can acquire credits for activities such as sponsoring the protection of carbon sequestration sources or the restoration of ecosystem service providers. In some cases, banks for handling such credits have been established and conservation companies have even gone public on stock exchanges, defining an evermore parallel link with economic endeavors and opportunities for tying into social perceptions.[38] However, crucial for implementation are clearly defined land rights, which is often lacking in many developing countries.[49] In particular, many forest-rich developing countries suffering deforestation experience conflict between different forest stakeholders.[49] In addition, concerns for such global transactions include inconsistent compensation for services or resources sacrificed elsewhere and misconceived warrants for irresponsible use. Another approach has been focused on protecting ecosystem service ‘hotspots’. Recognition that the conservation of many ecosystem services aligns with more traditional conservation goals (i.e. biodiversity) has led to the suggested merging of objectives for maximizing their mutual success. This may be particularly strategic when employing networks that permit the flow of services across landscapes, and might also facilitate securing the financial means to protect services through a diversification of investors.[50][51]

For example, in recent years there has been interest in the valuation of ecosystem services provided by shellfish production and restoration.[52] A keystone species, low in the food chain, bivalve shellfish such as oysters support a complex community of species by performing a number of functions essential to the diverse array of species that surround them. There is also increasing recognition that some shellfish species may impact or control many ecological processes; so much so that they are included on the list of “ecosystem engineers”organisms that physically, biologically or chemically modify the environment around them in ways that influence the health of other organisms.[53] Many of the ecological functions and processes performed or affected by shellfish contribute to human well-being by providing a stream of valuable ecosystem services over time by filtering out particulate materials and potentially mitigating water quality issues by controlling excess nutrients in the water.

Ecosystem-based adaptation or EbA is an emerging strategy for community development and environmental management that seeks to use an ecosystem services framework to help communities adapt to the effects of climate change. The Convention on Biological Diversity currently defines Ecosystem-Based Adaptation as “the use of biodiversity and ecosystem services to help people adapt to the adverse effects of climate change”, which includes the use of “sustainable management, conservation and restoration of ecosystems, as part of an overall adaptation strategy that takes into account the multiple social, economic and cultural co-benefits for local communities”.[54]

In 2001, the Millennium Ecosystem Assessment announced that humanity’s impact on the natural world was increasing to levels never before seen, and that the degradation of the planet’s ecosystems would become a major barrier to achieving the Millennium Development Goals. In recognition of this fact, Ecosystem-Based Adaptation seeks to use the restoration of ecosystems as a stepping-stone to improving the quality of life in communities experiencing the impacts of climate change. Specifically, this involves the restoration of ecosystems that provide the community with essential services, such as the provisioning of food and water and protection from storm surges and flooding. EbA interventions typically combine elements of both climate change mitigation and adaptation to global warming to help address the community’s current and future needs.[55]

Collaborative planning between scientists, policy makers, and community members is an essential element of Ecosystem-Based Adaptation. By drawing on the expertise of outside experts and local residents alike, EbA seeks to develop unique solutions to unique problems, rather than simply replicating past projects.[54]

Ecosystem services are defined as the gains acquired by humankind from surroundings ecosystems. Four different types of ecosystem services have been distinguished by the scientific body: regulating services, provisioning services, cultural services and supporting services. An ecosystem does not necessarily offer all four types of services simultaneously; but given the intricate nature of any ecosystem, it is usually assumed that humans benefit from a combination of these services. The services offered by diverse types of ecosystems (forests, seas, coral reefs, mangroves, etc.) differ in nature and in consequence. In fact, some services directly affect the livelihood of neighboring human populations (such as fresh water, food or aesthetic value, etc.) while other services affect general environmental conditions by which humans are indirectly impacted (such as climate change, erosion regulation or natural hazard regulation, etc.).[56]

Estuarine and coastal ecosystems are both marine ecosystems. An estuary is defined as the area in which a river meets the sea or the ocean. The waters surrounding this area are predominantly salty waters or brackish waters; and the incoming river water is dynamically motioned by the tide. An estuary strip may be covered by populations of reed (or similar plants) and/or sandbanks (or similar form or land).[citation needed]

A coastal ecosystem occurs in areas where the sea or ocean waters meet the land.[citation needed]

Regulating services are the “benefits obtained from the regulation of ecosystem processes”.[57] In the case of coastal and estuarine ecosystems, these services include climate regulation, waste treatment and disease control and natural hazard regulation.

Both the biotic and abiotic ensembles of marine ecosystems play a role in climate regulation. They act as sponges when it comes to gases in the atmosphere, retaining large levels of CO2 and other greenhouse gases (methane and nitrous oxide). Marine plants also use CO2 for photosynthesis purposes and help in reducing the atmospheric CO2. The oceans and seas absorb the heat from the atmosphere and redistribute it through the means of water currents, and atmospheric processes, such as evaporation and the reflection of light allow for the cooling and warming of the overlying atmosphere. The ocean temperatures are thus imperative to the regulation of the atmospheric temperatures in any part of the world: “without the ocean, the Earth would be unbearably hot during the daylight hours and frigidly cold, if not frozen, at night”.[58]

Another service offered by marine ecosystem is the treatment of wastes, thus helping in the regulation of diseases. Wastes can be diluted and detoxified through transport across marine ecosystems; pollutants are removed from the environment and stored, buried or recycled in marine ecosystems: “Marine ecosystems break down organic waste through microbial communities that filter water, reduce/limit the effects of eutrophication, and break down toxic hydrocarbons into their basic components such as carbon dioxide, nitrogen, phosphorus, and water”.[58] The fact that waste is diluted with large volumes of water and moves with water currents leads to the regulation of diseases and the reduction of toxics in seafood.

Coastal and estuarine ecosystems act as buffer zones against natural hazards and environmental disturbances, such as floods, cyclones, tidal surges and storms. The role they play is to “[absorb] a portion of the impact and thus [lessen] its effect on the land”.[58] Wetlands, for example, and the vegetation it supports trees, root mats, etc. retain large amounts of water (surface water, snowmelt, rain, groundwater) and then slowly releases them back, decreasing the likeliness of floods.[59] Mangrove forests protect coastal shorelines from tidal erosion or erosion by currents; a process that was studied after the 1999 cyclone that hit India. Villages that were surrounded with mangrove forests encountered less damages than other villages that weren’t protected by mangroves.[60]

Provisioning services consist of all “the products obtained from ecosystems”. Marine ecosystems provide people with: wild & cultured seafood, fresh water, fiber & fuel and biochemical & genetic resources.[citation needed]

Humans consume a large number of products originating from the seas, whether as a nutritious product or for use in other sectors: “More than one billion people worldwide, or one-sixth of the global population, rely on fish as their main source of animal protein. In 2000, marine and coastal fisheries accounted for 12 per cent of world food production”.[61] Fish and other edible marine products primarily fish, shellfish, roe and seaweeds constitute for populations living along the coast the main elements of the local cultural diets, norms and traditions. A very pertinent example would be sushi, the national food of Japan, which consists mostly of different types of fish and seaweed.

Water bodies that are not highly concentrated in salts are referred to as ‘fresh water’ bodies. Fresh water may run through lakes, rivers and streams, to name a few; but it is most prominently found in the frozen state or as soil moisture or buried deep underground. Fresh water is not only important for the survival of humans, but also for the survival of all the existing species of animals, plants.[citation needed]

Marine creatures provide us with the raw materials needed for the manufacturing of clothing, building materials (lime extracted from coral reefs), ornamental items and personal-use items (luffas, art and jewelry): “The skin of marine mammals for clothing, gas deposits for energy production, lime (extracted from coral reefs) for building construction, and the timber of mangroves and coastal forests for shelter are some of the more familiar uses of marine organisms. Raw marine materials are utilized for non-essential goods as well, such as shells and corals in ornamental items”.[61] Humans have also referred to processes within marine environments for the production of renewable energy: using the power of waves or tidal power as a source of energy for the powering of a turbine, for example.[citation needed] Oceans and seas are used as sites for offshore oil and gas installations, offshore wind farms.[citation needed]

Biochemical resources are compounds extracted from marine organisms for use in medicines, pharmaceuticals, cosmetics and other biochemical products. Genetic resources are the genetic information found in marine organisms that would later on be used for animal and plant breeding and for technological advances in the biological field. These resources are either directly taken out from an organism such as fish oil as a source of omega3 , or used as a model for innovative man-made products: “such as the construction of fiber optics technology based on the properties of sponges. … Compared to terrestrial products, marine-sourced products tend to be more highly bioactive, likely due to the fact that marine organisms have to retain their potency despite being diluted in the surrounding sea-water”.[61]

Cultural services relate to the non-material world, as they benefit the benefit recreational, aesthetic, cognitive and spiritual activities, which are not easily quantifiable in monetary terms.[citation needed]

Marine environments have been used by many as an inspiration for their works of art, music, architecture, traditions… Water environments are spiritually important as a lot of people view them as a means for rejuvenation and change of perspective. Many also consider the water as being a part of their personality, especially if they have lived near it since they were kids: they associate it to fond memories and past experiences. Living near water bodies for a long time results in a certain set of water activities that become a ritual in the lives of people and of the culture in the region.[citation needed]

Sea sports are very popular among coastal populations: surfing, snorkeling, whale watching, kayaking, recreational fishing…a lot of tourists also travel to resorts close to the sea or rivers or lakes to be able to experience these activities, and relax near the water.[citation needed]

A lot can be learned from marine processes, environments and organisms that could be implemented into our daily actions and into the scientific domain. Although much is still yet to still be known about the ocean world: “by the extraordinary intricacy and complexity of the marine environment and how it is influenced by large spatial scales, time lags, and cumulative effects”.[58]

Supporting services are the services that allow for the other ecosystem services to be present. They have indirect impacts on humans that last over a long period of time. Several services can be considered as being both supporting services and regulating/cultural/provisioning services.[citation needed]

Nutrient cycling is the movement of nutrients through an ecosystem by biotic and abiotic processes.[62] The ocean is a vast storage pool for these nutrients, such as carbon, nitrogen and phosphorus. The nutrients are absorbed by the basic organisms of the marine food web and are thus transferred from one organism to the other and from one ecosystem to the other. Nutrients are recycled through the life cycle of organisms as they die and decompose, releasing the nutrients into the neighboring environment. “The service of nutrient cycling eventually impacts all other ecosystem services as all living things require a constant supply of nutrients to survive”.[58]

Biologically mediated habitats are defined as being the habitats that living marine structures offer to other organisms.[63] These need not to be designed for the sole purpose of serving as a habitat, but happen to become living quarters whilst growing naturally. For example, coral reefs and mangrove forests are home to numerous species of fish, seaweed and shellfish… The importance of these habitats is that they allow for interactions between different species, aiding the provisioning of marine goods and services. They are also very important for the growth at the early life stages of marine species (breeding and bursary spaces), as they serve as a food source and as a shelter from predators.[citation needed]

Primary production refers to the production of organic matter, i.e., chemically bound energy, through processes such as photosynthesis and chemosynthesis. The organic matter produced by primary producers forms the basis of all food webs. Further, it generates oxygen (O2), a molecule necessary to sustain animals and humans.[64][65][66][67]

Ecosystem services degradation can pose a number of risks to corporate performance as well as provide business opportunities through ecosystem restoration and enhancement. Risks and opportunities include:

Many companies are not fully aware of the extent of their dependence and impact on ecosystems and the possible ramifications. Likewise, environmental management systems and environmental due diligence tools are more suited to handle “traditional” issues of pollution and natural resource consumption. Most focus on environmental impacts, not dependence. Several newly developed tools and methodologies can help the private sector value and assess ecosystem services. These include Our Ecosystem,[68] the Corporate Ecosystem Services Review (ESR),[69] Artificial Intelligence for Ecosystem Services (ARIES),[70] the Natural Value Initiative (NVI)[71] and InVEST (Integrated Valuation of Ecosystem Services & Tradeoffs) [72]

Ecosystem services decisions require making complex choices at the intersection of ecology, technology, society and the economy. The process of making ecosystem services decisions must consider the interaction of many types of information, honor all stakeholder viewpoints, including regulatory agencies, proposal proponents, decision makers, residents, NGOs, and measure the impacts on all four parts of the intersection. These decisions are usually spatial, always multi-objective, and based on uncertain data, models, and estimates. Often it is the combination of the best science combined with the stakeholder values, estimates and opinions that drive the process.[73]

One analytical study modeled the stakeholders as agents to support water resource management decisions in the Middle Rio Grande basin of New Mexico. This study focused on modeling the stakeholder inputs across a spatial decision, but ignored uncertainty.[74] Another study used Monte Carlo methods to exercise econometric models of landowner decisions in a study of the effects of land-use change. Here the stakeholder inputs were modeled as random effects to reflect the uncertainty.[75] A third study used a Bayesian decision support system to both model the uncertainty in the scientific information Bayes Nets and to assist collecting and fusing the input from stakeholders. This study was about siting wave energy devices off the Oregon Coast, but presents a general method for managing uncertain spatial science and stakeholder information in a decision making environment.[76] Remote sensing data and analyses can be used to assess the health and extent of land cover classes that provide ecosystem services, which aids in planning, management, monitoring of stakeholders’ actions, and communication between stakeholders.[77]

In Baltic countries scientists, nature conservationists and local authorities are implementing integrated planning approach for grassland ecosystems. They are developing Integrated Planning Tool that will be based on GIS (geographic information system) technology and put online that will help for planners to choose the best grassland management solution for concrete grassland. It will look holistically at the processes in the countryside and help to find best grassland management solutions by taking into account both natural and socioeconomic factors of the particular site.

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Ecosystem services – Wikipedia

Stem Cell Treatment | Arizona | Stem Cell Rejuvenation Center

ADIPOSE STEM CELL THERAPIES AND TREATMENTS

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Please Note: Although we have supplied links to the research journals above on the use of stem cells for specific conditions, we are not saying that any of these studies would relate to your particular condition, nor that it would even be an effective treatment. OurAutologousStem Cell Therapy is not an FDA approved treatment for any condition. We provide stem cell therapy (less than manipulated) as a service &as a practice of medicine only. Please see theFAQ pagefor more information. Thesejournal articlesare for educational purposes only &are not intended to be used to sell or promote our therapy.

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Stem Cell Treatment | Arizona | Stem Cell Rejuvenation Center

Stem cell

STEM CELL SUPPLEMENTS

Stem cells are cells with the ability to divide for indefinite periods in culture and to give rise to specialized cells.

Stem Cell Supplements are developed based on the merits of stem cells and they are applied for degenerative diseases treatments and to stimulate the formation of all the different tissues of the body: muscle, cartilage, tendon, ligament, bone, blood,nerve, organs, etc. Stem Cell Supplements bring essential health & antiaging benefits by providing necessary elements to the body to improve cellular rejuvenation, organ regeneration and tissue healing.

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Stem cell

Stem Cell Research & Therapy | Home page

“Stem cells have enormous potential for alleviating suffering for many diseases which currently have no effective therapy. The field has progressed to the clinic and it is important that this pathway is underpinned by excellent science and rigorous standards of clinical research. The journal provides an important avenue of publication in translational aspects of stem cell therapy spanning preclinical studies, clinical research and commercialization.”

Timothy O’Brien,Editor-in-Chief,Stem Cell Research & Therapy

“The study of stem cells is one of the most exciting areas of contemporary biomedical research. We believe that Stem Cell Research & Therapy will act as a highly active forum for both basic and translational research into stem cell biology and therapies. Specifically, by developing this forum for cutting edge research, we hope that Stem Cell Research & Therapy will play a significant role in bringing together the critical information to synergize stem cell science with stem cell therapies.”

Rocky S Tuan,Editor-in-Chief,Stem Cell Research & Therapy

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Stem Cells in Milwaukee, WI | Wisconsin Stem Cell Therapy

Dave, age 68, avid hunter and snow skier, his orthopedic surgeon suggested that he would need knee replacement surgery. He instead found relief through our powerful Stem Cell Therapy treatment protocol.

He said about his knee after our treatment, It is 85% better than when I walked in. I would recommend the procedure before trying anything else.

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Stem Cells in Milwaukee, WI | Wisconsin Stem Cell Therapy

Stem cell – Wikipedia

Stem cells are biological cells that can differentiate into other types of cells and can divide to produce more of the same type of stem cells. They are always and only found in the multicellular organisms.

In mammals, there are two broad types of stem cells: embryonic stem cells, which are isolated from the inner cell mass of blastocysts, and adult stem cells, which are found in various tissues. In adult organisms, stem cells and progenitor cells act as a repair system for the body, replenishing adult tissues. In a developing embryo, stem cells can differentiate into all the specialized cellsectoderm, endoderm and mesoderm (see induced pluripotent stem cells)but also maintain the normal turnover of regenerative organs, such as blood, skin, or intestinal tissues.

There are three known accessible sources of autologous adult stem cells in humans:

Stem cells can also be taken from umbilical cord blood just after birth. Of all stem cell types, autologous harvesting involves the least risk. By definition, autologous cells are obtained from one’s own body, just as one may bank his or her own blood for elective surgical procedures.

Adult stem cells are frequently used in various medical therapies (e.g., bone marrow transplantation). Stem cells can now be artificially grown and transformed (differentiated) into specialized cell types with characteristics consistent with cells of various tissues such as muscles or nerves. Embryonic cell lines and autologous embryonic stem cells generated through somatic cell nuclear transfer or dedifferentiation have also been proposed as promising candidates for future therapies.[2] Research into stem cells grew out of findings by Ernest A. McCulloch and James E. Till at the University of Toronto in the 1960s.[3][4]

The classical definition of a stem cell requires that it possesses two properties:

Two mechanisms exist to ensure that a stem cell population is maintained:

1. Obligatory asymmetric replication: a stem cell divides into one mother cell that is identical to the original stem cell, and another daughter cell that is differentiated.

When a stem cell self-renews it divides and does not disrupt the undifferentiated state. This self-renewal demands control of cell cycle as well as upkeep of multipotency or pluripotency, which all depends on the stem cell.[5]

2. Stochastic differentiation: when one stem cell develops into two differentiated daughter cells, another stem cell undergoes mitosis and produces two stem cells identical to the original.

Potency specifies the differentiation potential (the potential to differentiate into different cell types) of the stem cell.[6]

In practice, stem cells are identified by whether they can regenerate tissue. For example, the defining test for bone marrow or hematopoietic stem cells (HSCs) is the ability to transplant the cells and save an individual without HSCs. This demonstrates that the cells can produce new blood cells over a long term. It should also be possible to isolate stem cells from the transplanted individual, which can themselves be transplanted into another individual without HSCs, demonstrating that the stem cell was able to self-renew.

Properties of stem cells can be illustrated in vitro, using methods such as clonogenic assays, in which single cells are assessed for their ability to differentiate and self-renew.[9][10] Stem cells can also be isolated by their possession of a distinctive set of cell surface markers. However, in vitro culture conditions can alter the behavior of cells, making it unclear whether the cells shall behave in a similar manner in vivo. There is considerable debate as to whether some proposed adult cell populations are truly stem cells.[11]

Embryonic stem cells (ESCs) are the cells of the inner cell mass of a blastocyst, an early-stage embryo.[12] Human embryos reach the blastocyst stage 45 days post fertilization, at which time they consist of 50150 cells. ESCs are pluripotent and give rise during development to all derivatives of the three primary germ layers: ectoderm, endoderm and mesoderm. In other words, they can develop into each of the more than 200 cell types of the adult body when given sufficient and necessary stimulation for a specific cell type. They do not contribute to the extra-embryonic membranes or the placenta.

During embryonic development these inner cell mass cells continuously divide and become more specialized. For example, a portion of the ectoderm in the dorsal part of the embryo specializes as ‘neurectoderm’, which will become the future central nervous system.[13] Later in development, neurulation causes the neurectoderm to form the neural tube. At the neural tube stage, the anterior portion undergoes encephalization to generate or ‘pattern’ the basic form of the brain. At this stage of development, the principal cell type of the CNS is considered a neural stem cell. These neural stem cells are pluripotent, as they can generate a large diversity of many different neuron types, each with unique gene expression, morphological, and functional characteristics. The process of generating neurons from stem cells is called neurogenesis. One prominent example of a neural stem cell is the radial glial cell, so named because it has a distinctive bipolar morphology with highly elongated processes spanning the thickness of the neural tube wall, and because historically it shared some glial characteristics, most notably the expression of glial fibrillary acidic protein (GFAP).[14][15] The radial glial cell is the primary neural stem cell of the developing vertebrate CNS, and its cell body resides in the ventricular zone, adjacent to the developing ventricular system. Neural stem cells are committed to the neuronal lineages (neurons, astrocytes, and oligodendrocytes), and thus their potency is restricted.[13]

Nearly all research to date has made use of mouse embryonic stem cells (mES) or human embryonic stem cells (hES) derived from the early inner cell mass. Both have the essential stem cell characteristics, yet they require very different environments in order to maintain an undifferentiated state. Mouse ES cells are grown on a layer of gelatin as an extracellular matrix (for support) and require the presence of leukemia inhibitory factor (LIF) in serum media. A drug cocktail containing inhibitors to GSK3B and the MAPK/ERK pathway, called 2i, has also been shown to maintain pluripotency in stem cell culture.[16] Human ESCs are grown on a feeder layer of mouse embryonic fibroblasts and require the presence of basic fibroblast growth factor (bFGF or FGF-2).[17] Without optimal culture conditions or genetic manipulation,[18] embryonic stem cells will rapidly differentiate.

A human embryonic stem cell is also defined by the expression of several transcription factors and cell surface proteins. The transcription factors Oct-4, Nanog, and Sox2 form the core regulatory network that ensures the suppression of genes that lead to differentiation and the maintenance of pluripotency.[19] The cell surface antigens most commonly used to identify hES cells are the glycolipids stage specific embryonic antigen 3 and 4 and the keratan sulfate antigens Tra-1-60 and Tra-1-81. By using human embryonic stem cells to produce specialized cells like nerve cells or heart cells in the lab, scientists can gain access to adult human cells without taking tissue from patients. They can then study these specialized adult cells in detail to try and catch complications of diseases, or to study cells reactions to potentially new drugs. The molecular definition of a stem cell includes many more proteins and continues to be a topic of research.[20]

There are currently no approved treatments using embryonic stem cells. The first human trial was approved by the US Food and Drug Administration in January 2009.[21] However, the human trial was not initiated until October 13, 2010 in Atlanta for spinal cord injury research. On November 14, 2011 the company conducting the trial (Geron Corporation) announced that it will discontinue further development of its stem cell programs.[22] ES cells, being pluripotent cells, require specific signals for correct differentiationif injected directly into another body, ES cells will differentiate into many different types of cells, causing a teratoma. Differentiating ES cells into usable cells while avoiding transplant rejection are just a few of the hurdles that embryonic stem cell researchers still face.[23] Due to ethical considerations, many nations currently have moratoria or limitations on either human ES cell research or the production of new human ES cell lines. Because of their combined abilities of unlimited expansion and pluripotency, embryonic stem cells remain a theoretically potential source for regenerative medicine and tissue replacement after injury or disease.[24]

Human embryonic stem cell colony on mouse embryonic fibroblast feeder layer

The primitive stem cells located in the organs of fetuses are referred to as fetal stem cells.[25]There are two types of fetal stem cells:

Adult stem cells, also called somatic (from Greek , “of the body”) stem cells, are stem cells which maintain and repair the tissue in which they are found.[27] They can be found in children, as well as adults.[28]

Pluripotent adult stem cells are rare and generally small in number, but they can be found in umbilical cord blood and other tissues.[29] Bone marrow is a rich source of adult stem cells,[30] which have been used in treating several conditions including liver cirrhosis,[31] chronic limb ischemia [32] and endstage heart failure.[33] The quantity of bone marrow stem cells declines with age and is greater in males than females during reproductive years.[34] Much adult stem cell research to date has aimed to characterize their potency and self-renewal capabilities.[35] DNA damage accumulates with age in both stem cells and the cells that comprise the stem cell environment. This accumulation is considered to be responsible, at least in part, for increasing stem cell dysfunction with aging (see DNA damage theory of aging).[36]

Most adult stem cells are lineage-restricted (multipotent) and are generally referred to by their tissue origin (mesenchymal stem cell, adipose-derived stem cell, endothelial stem cell, dental pulp stem cell, etc.).[37][38] Muse cells (multi-lineage differentiating stress enduring cells) are a recently discovered pluripotent stem cell type found in multiple adult tissues, including adipose, dermal fibroblasts, and bone marrow. While rare, muse cells are identifiable by their expression of SSEA-3, a marker for undifferentiated stem cells, and general mesenchymal stem cells markers such as CD105. When subjected to single cell suspension culture, the cells will generate clusters that are similar to embryoid bodies in morphology as well as gene expression, including canonical pluripotency markers Oct4, Sox2, and Nanog.[39]

Adult stem cell treatments have been successfully used for many years to treat leukemia and related bone/blood cancers through bone marrow transplants.[40] Adult stem cells are also used in veterinary medicine to treat tendon and ligament injuries in horses.[41]

The use of adult stem cells in research and therapy is not as controversial as the use of embryonic stem cells, because the production of adult stem cells does not require the destruction of an embryo. Additionally, in instances where adult stem cells are obtained from the intended recipient (an autograft), the risk of rejection is essentially non-existent. Consequently, more US government funding is being provided for adult stem cell research.[42]

Multipotent stem cells are also found in amniotic fluid. These stem cells are very active, expand extensively without feeders and are not tumorigenic. Amniotic stem cells are multipotent and can differentiate in cells of adipogenic, osteogenic, myogenic, endothelial, hepatic and also neuronal lines.[43]Amniotic stem cells are a topic of active research.

Use of stem cells from amniotic fluid overcomes the ethical objections to using human embryos as a source of cells. Roman Catholic teaching forbids the use of embryonic stem cells in experimentation; accordingly, the Vatican newspaper “Osservatore Romano” called amniotic stem cells “the future of medicine”.[44]

It is possible to collect amniotic stem cells for donors or for autologuous use: the first US amniotic stem cells bank [45][46] was opened in 2009 in Medford, MA, by Biocell Center Corporation[47][48][49] and collaborates with various hospitals and universities all over the world.[50]

Adult stem cells have limitations with their potency; unlike embryonic stem cells (ESCs), they are not able to differentiate into cells from all three germ layers. As such, they are deemed multipotent.

However, reprogramming allows for the creation of pluripotent cells, induced pluripotent stem cells (iPSCs), from adult cells. These are not adult stem cells, but adult cells (e.g. epithelial cells) reprogrammed to give rise to cells with pluripotent capabilities. Using genetic reprogramming with protein transcription factors, pluripotent stem cells with ESC-like capabilities have been derived.[51][52][53] The first demonstration of induced pluripotent stem cells was conducted by Shinya Yamanaka and his colleagues at Kyoto University.[54] They used the transcription factors Oct3/4, Sox2, c-Myc, and Klf4 to reprogram mouse fibroblast cells into pluripotent cells.[51][55] Subsequent work used these factors to induce pluripotency in human fibroblast cells.[56] Junying Yu, James Thomson, and their colleagues at the University of WisconsinMadison used a different set of factors, Oct4, Sox2, Nanog and Lin28, and carried out their experiments using cells from human foreskin.[51][57] However, they were able to replicate Yamanaka’s finding that inducing pluripotency in human cells was possible.

Induced pluripotent stem cells differ from embryonic stem cells. They share many similar properties, such as pluripotency and differentiation potential, the expression of pluripotency genes, epigenetic patterns, embryoid body and teratoma formation, and viable chimera formation,[54][55] but there are many differences within these properties. The chromatin of iPSCs appears to be more “closed” or methylated than that of ESCs.[54][55] Similarly, the gene expression pattern between ESCs and iPSCs, or even iPSCs sourced from different origins.[54] There are thus questions about the “completeness” of reprogramming and the somatic memory of induced pluripotent stem cells. Despite this, inducing adult cells to be pluripotent appears to be viable.

As a result of the success of these experiments, Ian Wilmut, who helped create the first cloned animal Dolly the Sheep, has announced that he will abandon somatic cell nuclear transfer as an avenue of research.[58]

Furthermore, induced pluripotent stem cells provide several therapeutic advantages. Like ESCs, they are pluripotent. They thus have great differentiation potential; theoretically, they could produce any cell within the human body (if reprogramming to pluripotency was “complete”).[54] Moreover, unlike ESCs, they potentially could allow doctors to create a pluripotent stem cell line for each individual patient.[59] Frozen blood samples can be used as a valuable source of induced pluripotent stem cells.[60] Patient specific stem cells allow for the screening for side effects before drug treatment, as well as the reduced risk of transplantation rejection.[59] Despite their current limited use therapeutically, iPSCs hold create potential for future use in medical treatment and research.

To ensure self-renewal, stem cells undergo two types of cell division (see Stem cell division and differentiation diagram). Symmetric division gives rise to two identical daughter cells both endowed with stem cell properties. Asymmetric division, on the other hand, produces only one stem cell and a progenitor cell with limited self-renewal potential. Progenitors can go through several rounds of cell division before terminally differentiating into a mature cell. It is possible that the molecular distinction between symmetric and asymmetric divisions lies in differential segregation of cell membrane proteins (such as receptors) between the daughter cells.[61]

An alternative theory is that stem cells remain undifferentiated due to environmental cues in their particular niche. Stem cells differentiate when they leave that niche or no longer receive those signals. Studies in Drosophila germarium have identified the signals decapentaplegic and adherens junctions that prevent germarium stem cells from differentiating.[62][63]

Stem cell therapy is the use of stem cells to treat or prevent a disease or condition. Bone marrow transplant is a form of stem cell therapy that has been used for many years without controversy.[64][65]

Stem cell treatments may lower symptoms of the disease or condition that is being treated. The lowering of symptoms may allow patients to reduce the drug intake of the disease or condition. Stem cell treatment may also provide knowledge for society to further stem cell understanding and future treatments.[66]

Stem cell treatments may require immunosuppression because of a requirement for radiation before the transplant to remove the person’s previous cells, or because the patient’s immune system may target the stem cells. One approach to avoid the second possibility is to use stem cells from the same patient who is being treated.

Pluripotency in certain stem cells could also make it difficult to obtain a specific cell type. It is also difficult to obtain the exact cell type needed, because not all cells in a population differentiate uniformly. Undifferentiated cells can create tissues other than desired types.[67]

Some stem cells form tumors after transplantation;[68] pluripotency is linked to tumor formation especially in embryonic stem cells, fetal proper stem cells, induced pluripotent stem cells. Fetal proper stem cells form tumors despite multipotency.[69]

Some of the fundamental patents covering human embryonic stem cells are owned by the Wisconsin Alumni Research Foundation (WARF) they are patents 5,843,780, 6,200,806, and 7,029,913 invented by James A. Thomson. WARF does not enforce these patents against academic scientists, but does enforce them against companies.[70]

In 2006, a request for the US Patent and Trademark Office (USPTO) to re-examine the three patents was filed by the Public Patent Foundation on behalf of its client, the non-profit patent-watchdog group Consumer Watchdog (formerly the Foundation for Taxpayer and Consumer Rights).[70] In the re-examination process, which involves several rounds of discussion between the USPTO and the parties, the USPTO initially agreed with Consumer Watchdog and rejected all the claims in all three patents,[71] however in response, WARF amended the claims of all three patents to make them more narrow, and in 2008 the USPTO found the amended claims in all three patents to be patentable. The decision on one of the patents (7,029,913) was appealable, while the decisions on the other two were not.[72][73] Consumer Watchdog appealed the granting of the ‘913 patent to the USPTO’s Board of Patent Appeals and Interferences (BPAI) which granted the appeal, and in 2010 the BPAI decided that the amended claims of the ‘913 patent were not patentable.[74] However, WARF was able to re-open prosecution of the case and did so, amending the claims of the ‘913 patent again to make them more narrow, and in January 2013 the amended claims were allowed.[75]

In July 2013, Consumer Watchdog announced that it would appeal the decision to allow the claims of the ‘913 patent to the US Court of Appeals for the Federal Circuit (CAFC), the federal appeals court that hears patent cases.[76] At a hearing in December 2013, the CAFC raised the question of whether Consumer Watchdog had legal standing to appeal; the case could not proceed until that issue was resolved.[77]

Diseases and conditions where stem cell treatment is being investigated include:

Research is underway to develop various sources for stem cells, and to apply stem cell treatments for neurodegenerative diseases and conditions, diabetes, heart disease, and other conditions.[93] Research is also underway in generating organoids using stem cells, which would allow for further understanding of human development, organogenesis, and modeling of human diseases.[94]

In more recent years, with the ability of scientists to isolate and culture embryonic stem cells, and with scientists’ growing ability to create stem cells using somatic cell nuclear transfer and techniques to create induced pluripotent stem cells, controversy has crept in, both related to abortion politics and to human cloning.

Hepatotoxicity and drug-induced liver injury account for a substantial number of failures of new drugs in development and market withdrawal, highlighting the need for screening assays such as stem cell-derived hepatocyte-like cells, that are capable of detecting toxicity early in the drug development process.[95]

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Stem cell – Wikipedia

National Stem Cell Centers | Stem Cell Therapy in New York …

At National Stem Cell Centers, our affiliate physicians focus on leading edge, regenerative medicine. Instead of synthetic compounds, prescription medications, or surgical procedures, they activate your own natural cellular resources to promote healing.

Our goal is to allow patients access to this potentially revolutionary form of treatment to harness your bodys natural healing cascade mechanism for the repair of damaged tissues.

Adult mesenchymal stem cells are a form of undifferentiated cells. These kinds of stem cells are found in great abundance within abdominal adipose (fatty) tissue and bone marrow. Lying dormant (non-replicating), these remarkably intelligent cells can be activated to become other kinds of cells specific to tendons, muscle, blood vessels, nerves, and bone.

This means that regenerative cell therapies can be helpful in reducing pain, chronic inflammation, and the mitigation of some degenerative disease states.

At National Stem Cell Centers, our affiliated physicians utilize autologous stem cells harvested from your own tissue, without any form of artificial cellular manipulation, enzymes, expansion or multiplication.

Conditions Addressed

Anecdotal evidence including patient feedback suggests that stem cell procedures may be helpful in addressing conditions and injuries such as joint pain including knee pain, arthritis, osteoarthritis, back pain, and chronic inflammation.

As technology evolves, autoimmune and neurological disorders, orthopedic and urological conditions, heart and lung diseases, erectile dysfunction (ED), hair loss, cellular rejuvenation, autism, and aesthetics could be addressed as well.

Why National Stem Cell Centers?

There are many reasons you should choose our affiliated physicians including:- Our doctors are surgeons, not ordinary physicians- FDA registered tissue processing lab- No multiplication/duplication/expansion of cells- Numerous happy patients as evidenced by our 5 Star Reviews- IND and IRB Applications in preparation- Initiating participation in clinical trials- Affordable prices- Zero percent financing

Call today to find out if you are a candidate and to schedule a complimentary consultation. National Stem Cell Centers has affiliate physicians in New York City, Great Neck, Hauppauge and Southampton, Long Island, New Jersey, Dallas and Houston in Texas, and Newport Beach, California.

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National Stem Cell Centers | Stem Cell Therapy in New York …

Is Stem Cell Therapy Covered by Medicare?

Stem cell therapy has been a hot topic in the press lately. With more and more medical providers offering stem cell treatments, patients around the country have been wondering, Is Stem Cell Therapy covered by Medicare.

Stem Cell research has shown that its an effective treatment for chronic joint pain and arthritis sufferers and more recent studies are starting to show the benefit for treatment of neurological disorders as well. (M.S., Parkinsons, and Stroke)

So the team at Stem Cell: The Magazine, have put together some information to answer this question of insurance coverage for potential medical enrollees seeking stem cell and regenerative treatments.

So what is the answer to Does Medicare cover Stem Cell therapy?

From the research that we have pulled up regarding Medicare Insurance Coverage for stem cell therapy; medicare does cover stem cell treatments, but not for some of the chronic degenerative conditions that regenerative treatments (stem cell therapy) can help them with.

You can see in this publication from BCBS that stem cell therapy is covered for the following conditions:

INDICATIONS FOR COVERAGE

Section 2.aAllogeneic Hematopoietic Stem Cell Transplantation (HSCT) eligible for coverage in the following:a) The treatment of leukemiab) The treatment of severe combined immunodeficiency disease (SCID) and for the treatment of Wiskott-Aldrich syndrome.ORc) The treatment of Myelodysplastic Syndromes (MDS) pursuant to Coverage with Evidence Development (CED) in the context of a Medicare-approved, prospective clinical study.3. Autologous Stem Cell Transplantation(AuSCT) is eligible for coverage in the following:a) Acute leukemia in remission who have a high probability of relapse and whohave no human leucocyte antigens (HLA)-matched;ORb) Resistant non-Hodgkins lymphomas or those presenting with poor prognosticfeatures following an initial response;ORc) Recurrent or refractory neuroblastoma;ORd) Advanced Hodgkins disease who have failed conventional therapy and have no HLA-matched donor.

You can see that outside of the listed conditions above, Medicare does not cover stem cell therapy for treatments joint conditions or neurological conditions that patients are more commonly seeking treatment for.

In this article, it clearly states that stem cell therapy for the coverage of orthopedic conditions is not covered:

The orthopedic application of stem-cell therapy is not addressed within the stem cell transplantation NCD. (NCD = National Care Determinations)

What this means for any patient that is looking to receive regenerative and stem cell treatments for orthopedic conditions such as:

M

M

Download our free Stem Cell 101 educational report now!

Medicare will not cover treatment for these conditions. In fact, most major medical carriers will not provide coverage for these treatments either.

Many chronic joint pain sufferers wonder why Medicare and most major carriers dont provide coverage for these treatments if they are so effective, but there is a simple answer for why this is.

Medicare and most major health insurance are for emergency conditions. Regenerative medicine is still considered an elective treatment, close to wellness care. Insurance carriers are not in the business of providing wellness for coverage for their participants.

We found a great video that explains more about this by John R Hoffman at Arcadia University. In it he describes the challenges of Medicare coverage for Stem Cell Therapy.

Our hope at Stem Cell: The Magazine is that as more and more patients continue to seek out treatment of their orthopedic and neurological conditions using stem cell and regenerative treatments, that Mediare and major health insurances will accept stem cell as the first treatment for these chronic conditions.

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Is Stem Cell Therapy Covered by Medicare? was last modified: October 3rd, 2018 by Stem Cell The Magazine

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Is Stem Cell Therapy Covered by Medicare?

Home – Stem Cell Therapy in Orlando, Florida

A Breakthrough Technology

Stem Cell Therapy is a procedure in which new cells are introduced directly into an injurious area or joint, promoting healing and growth. The multitude of administered cells allows the body to proceed with the healing process at an accelerated rate. This treatment has been recognized by the medical industry worldwide as the biggest medical breakthrough in natural healing. Athletes such as Kobe Bryant, Alex Rodriguez and Peyton Manning have traveled abroad for this unique treatment. And now, SCI brings this same solution to you right here in Florida.

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Stem Cell Therapy & Treatment Center | TruStem Cell Therapy

Patient-Centric Care

At TruStem Cell Therapy, we focus on patient-centric care that has the potential to improve the quality of the patients life with less risk of complication.

Some patients experience mild soreness after harvesting and bruising that clears up quickly. The therapy can takes 1 day to complete. This is a same day procedure. The visit is 3 days.

Adult stem cell therapy for chronic disease is a safe and effective therapy to improve disease-related symptoms. Thus, patients with conditions such as stroke, osteoarthritis, inflammatory bowel disease or critical limb ischemia may feel better and live fuller lives.

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Stem Cell Therapy & Treatment Center | TruStem Cell Therapy

Stem Cell Therapy for Anti-Aging and Sexual Performance …

Stem Cell Therapy has been around for quite some time, but due to high cost it was primarily used for recovery in athletes and the financial elite. However, with the progression of science and knowledge, stem cell therapy has become much more widely used and financially attainable.

Tampa Rejuvenation is the first in Tampa Bay to utilize the benefits of stem cell therapy for the purpose of anti-aging and sexual performance. We realize as our patients age, their bodies no longer have the regenerative properties to attain the desired results from using their growth factors alone as with our PRP, or Plasma Rich Platelet, therapy. Although many patients will still yield improvement with the PRP alone, the magnitude of cytokines and growth factors in your blood as you age will deplete with age. By implementing stem cell therapy, the number of growth factors are exponential allowing our bodies to regenerate on a magnitude that is otherwise unattainable with some results lasting for 3-5 years.

Stem Cell Therapy can be used to restore vitality to the skin, encourage the growth of hair, and even restore sexual performance and pleasure.

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Stem Cell Therapy for Anti-Aging and Sexual Performance …

NSI Stem Cell | What Is Stem Cell Therapy?

This innovative therapy option for alleviating pain and restoring function in the body could be the answer youve been looking for! We know you may have tried everything, and may have seen numerous doctors to take care of your condition, without real success. This can be very frustrating and can cause a lot of stress on you and your family. It is very important to your recovery to find someone that understands your journey and what you have been through along the way.

You may have been through the ringer with your injury or condition. Many of our patients have spent years getting their hopes up, and then getting their hopes dashed.

Stem Cell Therapy is about using your bodys own stem cells to regenerate damagedtissue. So if you, or someone you love, is suffering please read on to find out who can be helped and how.

Our Stem Cell Therapy is an innovative therapy that is recommendedfor a wide variety of chronic conditions, yet many people are learning about it now for the first time.

These are not embryonic stem cells or cells from fetuses.These regenerative cells come straight from your own body.

They are extracted just a few hours before theyre injected back into your body and put to work to heal damaged or dysfunctional tissue.

We use a variety of stem cells derived from the patients own tissues. Our preferred choice is bone marrow or fat because the cells there are multi-potent which means that they have the ability to differentiate into muscle, tendons, ligaments, bone, and cartilage. Once introduced into the damaged or diseased area, the stem cells can then heal your damaged tissue and regenerate new healthy tissue.

Stem Cell Therapy offers significant potential for the healing of tissues that have become injured as a result of the aging process.

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NSI Stem Cell | What Is Stem Cell Therapy?