A New Nanobot Drills Through Your Eyeball to Deliver Drugs

Mobile Bots

Famed futurist Ray Kurzweil thinks tiny robots will flow through our bodies by 2030 to help us stay healthy. We now have one more reason to believe he’s right.

Compelling nanobots to move through liquids such as blood has proven tricky but doable. It’s been much harder to get tiny bots to navigate dense tissues, such as those found in the eyeball, without damaging them.

Thanks to a bit of design ingenuity, though, an international team of researchers has managed to create a nanobot that can do just that.

Teflon-Inspired

The team describes how a few key design features gave their propeller-shaped nanobot that unique ability in a paper published Friday in the journal Science Advances.

First, the bot is incredibly tiny, approximately 200 times smaller in diameter than a human hair. Second, a non-stick coating helps it slip through dense tissue. And finally, the inclusion of a bit of magnetic material in the nanobots makes them easy to steer with an external magnetic field.

To test the nanobots, the researchers injected tens of thousands of them into a dissected pig’s eye. Using a magnetic field, they were able to direct the swarm to the retina at the back of the pig’s eye — just as they’d hoped.

Drugs On Demand

Eventually, the researchers believe this technique will allow them to deliver drugs directly to hard to reach parts of the human body — not just the back of the eyeball.

“That is our vision,” researcher Tian Qiu said in a press release. “We want to be able to use our nanopropellers as tools in the minimally-invasive treatment of all kinds of diseases, where the problematic area is hard to reach and surrounded by dense tissue. Not too far in the future, we will be able to load them with drugs.”

READ MORE: Nanorobots Propel Through the Eye [Max Planck Institute for Intelligent Systems]

More on nanobots: Kurzweil: By 2030, Nanobots Will Flow Throughout Our Bodies

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A New Nanobot Drills Through Your Eyeball to Deliver Drugs

To Fight Climate Change, The Poor Would Spend More Than The Rich

Pale Blue Dot

We’re running out of time to avoid a planetary climate change catastrophe. And while the global poor already face problems caused by rising temperatures and severe weather, political leaders often seem frozen.

A new experiment, published last week in the journal PLOS ONE, suggests that those with the resources to change the world are hesitant to do their part. That’s a bummer: If the world is going to make it, we’ll all need to do what we can to slow climate change.

Going Dutch

In the study, researchers gave groups of people different amounts of money that they could choose to keep or donate towards a common goal that would specifically help fight climate change. Those who were given a larger share of the pot were less likely to contribute, while those who were given less money offered most of their donations.

Of course, the study had limitations. Researchers only gave the participants between 20 and 60 euros each, which is chump change compared to the sums involved in the global climate. Still, the finding was a gloomy reflection of the fact that the wealthy cause far more harm to the environment than the poor and do less to clean it up.

Storm the Castle

Perhaps it’s not time to grab a pitchfork and form an angry mob quite yet, but it’s easy to see this new study as a reflection of the many ways that climate change is already hurting the most vulnerable among us — and how the richest seem content to let it happen.

Of course, this is one limited experiment, and the number of participants involved is way too small to extrapolate these results to global politics. All the same, it revealed an unfortunate glimpse into what happens when some get far more money than they need.

READ MORE: Wealthier people do less in the struggle against climate change [Universitat Rovira i Virgili]

More on billionaires: Disrupting the Reaper: Tech Titans’ Quest for Immortality Rages Forward

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To Fight Climate Change, The Poor Would Spend More Than The Rich

China’s New Space Station Is Called The “Heavenly Palace”

Heavenly Palace

The first components of the International Space Station (ISS) launched into space more than 20 years ago, and it’s been continuously occupied for 18. Right now, it’s the only operational space station in orbit — but that’s about to change.

China just unveiled a life-size replica of the country’s new space station at Airshow China, the largest aerospace exhibition in the country. The new station is called Tiangong, which means “Heavenly Palace” in Chinese.

American Football

The new ISS competitor’s central module is 55 feet (17 meters) long, weighs 60 tons, and can fit three astronauts. That’s actually quite a bit smaller than the ISS, which is about as large as an American football field if you count its large solar panels.

WANG ZHAO/AFP/Getty Images

The new space station will allow astronauts to conduct cutting-edge scientific research in the fields of biology and microgravity, according to the Associated Press.

The new station will technically belong to China, but will open its doors to all UN countries. Construction is expected to be completed around 2022.

Here’s to hoping that China’s new space station will fare better than the Tiangong-1 space lab, which crashed into the Pacific earlier this year after authorities lost control of it in orbit.

READ MORE: China unveils new ‘Heavenly Palace’ space station as ISS days numbered [Phys.org]

More on Tiangong-1: The Chinese Space Station Has Crashed in the Pacific. Why Was It So Hard to Track?

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China’s New Space Station Is Called The “Heavenly Palace”

SpaceX Reveals How It Would Handle an Astronaut Emergency

Ready for Anything

When it comes to space travel, we can’t overprepare — countless things could go wrong at any step in the process, and even a brief delay in response could be the difference between life and death.

To that end, Elon Musk’s SpaceX recently demonstrated it was ready to handle one of our worst-case space flight scenarios: an injured or sick astronaut.

Testing the Waters

SpaceX will eventually transport astronauts to and from the International Space Station aboard its Crew Dragon spacecraft as part of NASA’s Commercial Crew program.

Some of those return flights will end with the Crew Dragon splashing down in the ocean near Florida’s eastern coast. A crane aboard SpaceX’s recovery ship, GO Searcher, will then lift the craft from the water and place it onto the ship’s main deck. Doctors can then evaluate the returning crew to ensure they’re in good shape before GO Searcher heads to Cape Canaveral.

At least, that’s if everything goes according to plan. If the astronauts aboard the Crew Dragon are sick or injured, SpaceX will need to get them medical attention as quickly as possible.

To prepare for that possibility, SpaceX rehearsed a scenario in which a helicopter landed on GO Searcher. The crew then loaded a stretcher onto the aircraft for transportation to a nearby hospital. The helicopter is also equipped to transport doctors and other medical personnel to GO Searcher so they can care for patients at the ship’s medical treatment facility.

Prior Preparation

SpaceX is ahead of the game with this dress rehearsal — there isn’t even a date set yet for the first water landing of an astronaut-carrying Crew Dragon.

Still, it’s encouraging to know Elon Musk’s space company is taking every precaution to ensure it’s prepared to provide NASA astronauts with the best possible medical care long before they might ever need it.

READ MORE: SpaceX Rehearses Helicopter Landing at Sea [NASA]

More on the Commercial Crew program: NASA Announces the First Commercial Astronauts to Pilot the Next Generation of Spacecraft

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SpaceX Reveals How It Would Handle an Astronaut Emergency

AI Can Tell If You’re Depressed by Listening to You Talk

Diagnosing Depression

Depression can manifest with many different symptoms, from a “loss of energy” to “indecisiveness” — broad criteria that make the condition difficult to diagnose with a high degree of certainty.

Now, researchers at MIT’s Computer Science and Artificial Intelligence Laboratory are working on an algorithm that could eliminate some of that guesswork. They used text and audio data from 142 interviews with patients — 30 of whom had been diagnosed with depression — to teach a machine learning algorithm to listen for signs of depression in speech.

Tone of Voice

What makes this effort stand out is that the researchers examined the patients’ tone of voice, not just the specific words they used. That technique made the model surprisingly accurate: It was able to identify subjects who had been diagnosed with depression with a 77 percent success rate.

But before we go on and implement AI as a tool to diagnose mental disorders in the real world, we’ll have to take these results with a substantial grain of salt.

AI Therapy

While chatbots like Woebot have recently surfaced help people to deal with depression, they won’t be able to replace a human therapist, at least for the time being.

There are far too many variables, and while 77 percent sounds promising, a false positive could raise serious ethical concerns. For instance, AI diagnostic tools could fall into the wrong hands — like your employer or insurance company.

But the researchers are realistic about their machine learning model’s ability to detect depression. Rather than replacing human therapists, they see it as another tool in [a clinician’s] toolbox,” MIT researcher James Glass, who worked on the model, told Smithsonian.

READ MORECan Artificial Intelligence Detect Depression in a Person’s Voice? [Smithsonian]

More on treating depression: New App for Depression Uses Artificial Intelligence for Therapy Treatments

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AI Can Tell If You’re Depressed by Listening to You Talk

This Gadget Tells You Exactly What Allergens You’re Inhaling

Allergic Reaction

Every minute you’re outside, you’re likely inhaling hundreds of “bioaerosols” — pollens, spores, microbes, and other tiny objects that can cause allergic reactions.

Today’s best method for measuring that allergen load is decidedly low-tech — researchers catch bioaerosols in filters or spore traps and study them under a microscope to identify each one. But a new gadget, hacked together by UCLA researchers, uses machine learning to dramatically speed up that process. Eventually, it might even give you a better sense of the air you’re breathing.

Pollen Kingdom

The UCLA researchers describe their device, which they built for less than $200 in parts, in a new paper published in the journal ACS Photonics. 

Basically, the apparatus catches bioaerosols on a sticky surface and scans them with a laser and a small sensor. Then it feeds the resulting image into a neural network trained to recognize common allergens such as oak, ragweed pollen, and certain mold spores. Finally, it tells you exactly what’s making you sneeze.

Air Apparent

Though promising, the UCLA prototype isn’t quite ready for action. Its algorithm can only recognize five allergens, and its accuracy is a good-not-great 94 percent.

But incremental improvements could result in a compelling gadget that would let you analyze the air around you — and maybe decide whether it’s time to pop an antihistamine.

READ MORE: New Mobile Device Identifies Airborne Allergens Using Deep Learning [UCLA]

More on allergies: The FDA Has Approved a Faster Way to Check for Allergies

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This Gadget Tells You Exactly What Allergens You’re Inhaling

Our Efforts to Heal the Ozone Layer Are Finally Paying Off

Good News, Everyone

It seems like every recent study on the environment has had the same takeaway: We’re heading toward a climate catastrophe.

A newly released report backed by the United Nations bucks that trend with some very positive news. It seems our global efforts to repair the ozone layer are actually paying off — and even better, future efforts already in the works have the potential to help us address global warming.

How’s that for a breath of fresh, non-toxic air?

In the Zone

Every four years, an international team of researchers releases a report focused on the state of Earth’s stratospheric ozone, a naturally occurring gas that shields the planet from ultraviolet (UV) radiation.

Unfortunately, our actions on Earth have had a detrimental effect on the ozone layer. For decades, we pumped chemicals called chlorofluorocarbons (CFCs) into the air, and these depleted the ozone layer, leaving us vulnerable to that harmful UV radiation.

In 1987, the world decided to take action against this damage to the ozone layer through the Montreal Protocol, an international treaty focused primarily on the phasing out of CFCs. As of 2010, the harmful chemicals were completely banned.

Based on this newly released report, those efforts have paid off.

Ozone in certain parts of the stratosphere has increased by 1 to 3 percent every decade since 2000. Based on current projections, the ozone layer above the Northern Hemisphere will be completely healed by the 2030s, with the Southern Hemisphere following in the 2050s and the polar regions by 2060.

Building Momentum

Though the findings of this new report are promising, we are far from any sort of “mission accomplished” moment when it comes to the ozone.

We already know that not everyone is abiding by the CFC ban — looking at you, China — so we’ll need to figure out a way to address that issue.

We’re also just months away from the implementation of the Kigali Amendment, an update to the Montreal Protocol that will guide the phasing out of another type of harmful chemical, hydroflourocarbons (HFCs). This amendment has the potential to not only build on the ozone-repair efforts already in place, but also help us avoid up to 0.4 percent of global warming this century, so we’ll need to ensure the world is as committed to phasing out HFCs as it has been CFCs.

If we can do that, who knows? Maybe environmental reports containing positive news could become the norm.

READ MORE: Healing of Ozone Layer Gives Hope for Climate Action: UN Report [UN News]

More on CFCs: Report Identifies China as the Source of Ozone-Destroying Emissions

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Our Efforts to Heal the Ozone Layer Are Finally Paying Off

China Can Now Identify a Citizen Based on Their Walk

Big Brother

China’s latest weapon in its war against citizen privacy: gait recognition software.

According to a new story by the Associated Press, police in Beijing and Shanghai are using a gait recognition system developed by artificial intelligence company Watrix to identify Chinese citizens — even when their faces aren’t visible.

Walk This Way

Watrix claims its system can identify a person from up to 165 feet away even if their back is to a camera or their face turned away. It doesn’t require any special cameras, either — it can analyze existing surveillance footage to ID an individual with 94 percent accuracy.

“You don’t need people’s cooperation for us to be able to recognize their identity,” Watrix CEO Huang Yongzhen told the AP. “Gait analysis can’t be fooled by simply limping, walking with splayed feet, or hunching over, because we’re analyzing all the features of an entire body.”

However, the software doesn’t yet work in real time. It needs roughly 10 minutes to analyze about an hour’s worth of video, during which time it extracts a person’s silhouette and then creates a model of their individual gait.

Eyes Everywhere

It’s easy to see how this technology could be useful on a smaller scale. A company could produce a database of all its employees’ gaits and then use that database to ensure unauthorized individuals aren’t in restricted areas.

It’s harder to imagine how China could make use of the technology on a nationwide scale, though.

Facial recognition tech is easy to implement because the faces of most citizens are already in government databases. Would the nation need to produce a similar database of citizen gaits? Or would the tech work retroactively — arrest someone for a crime, have them walk for you, and then compare their gait to that of the criminal caught on camera?

Whatever the case may be, police in Beijing and Shanghai are making use of this tech somehow, which means it might just be a matter of time before anyone on the move in China will find themselves under the watchful eye of the nation’s government.

READ MORE: Chinese ‘Gait Recognition’ Tech IDs People by How They Walk [Associated Press]

More on Chinese surveillance: If You Jaywalk in China, Facial Recognition Means You’ll Walk Away With a Fine

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China Can Now Identify a Citizen Based on Their Walk

Unless Governments Get Involved, Plant-Based Meat Won’t Take Off

Meatless Monday

Plant-based meats are finally taking off: animal-free beef is popping up everywhere from high-end burger joints to, uh, biochemical research facilities.

Fine, plant-based and 3D-printed burgers, steaks, and chicken cutlets haven’t quite yet liberated the world’s livestock. But the technology behind these scientific snacks is progressing — with enough support, food researcher Jacy Reese predicts in a new book that we could replace a good chunk of traditional meats in a matter of decades.

Let Them Eat Steak

If we want to prevent catastrophic levels of global climate change, we need to farm and eat less meat. The various startups working on fake meat, perhaps the most famous of which is Impossible Foods, are pursuing an ambitious workaround: bringing cheap, sustainable food to the world without completely making people give up meat.

“In addition to contributing towards decreasing the effect of livestock on climate change, desertification and avoid animals slaughter, the development of these kinds of technological advances should help the populations living in the rural areas of our planet to have better access to healthy food and a varied diet,” Giuseppe Scionti, a biomedical researcher who found a way to 3D print realistic chicken cutlets and steaks, told Futurism.

Hamburger Helper

But major governments need to step in if these plant-based meats are ever going to get out of bougie restaurants and into the hungry mouths of the world.

Without massive structural investments, Fast Company’s reporting corroborated, plant-based meats will be stuck as a fad diet and may never become widespread and inexpensive enough to help the world.

READ MORE: Can we end animal farming by the end of the century? [Fast Company]

More on changing diets: To Feed a Hungry Planet, We’re all Going to Need to eat Less Meat

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Unless Governments Get Involved, Plant-Based Meat Won’t Take Off

Amazon River Ecosystem and Biodiversity | Discover Peru

The Amazon River is the greatest river of South America and its biodiversity the richest of any river in the world. Its waters are populated by 2,500 different species of fish, scientists believe that there are many more that have not been identified yet. Mammals, amphibians and water snakes also call the Amazon River home. The river has been a source of protein for the local population for thousands of years and a source of fresh water.

The Amazon River and its tributaries have depleted and eroded the land removing almost all its nutrients and leaving an extremely poor soil. How does the Amazon rainforest exist? It exists because of nutrient recycling. As plants die insects and microbes decompose them releasing nutrients that support new plants. Near water sources as plants absorb the energy from the sun vegetation becomes dense but trees do not grow very tall. Many animals that live in the Amazon River depend on the recycling of nutrients as they feed from plants and algae. This system of recycling has sustained life in the Amazon rainforest for millions of years.

Animal life support each other in the Amazon River by serving as food to other animals above the food chain. Their bodies carry nutrients that eventually serve as fertilizer, feeding the forest and the fauna of the Amazon River ecosystem.

Some species of animals are exclusively found in theAmazon River and many of them are in danger of extinction. For the last 20 years the governments of Peru and Brazil along with conservation organizations, local businesses and indigenous people have been working together to protect endangered species for the enjoyment of the world and future generations.

The following animals are unique to the Amazon river and its tributaries:

One of the most endangered species in the Amazon River is the pink dolphin or bufeo thought to be extinct more than twenty years ago. They are very rarely seen and are found only in the Amazonian rivers around Iquitos. Their pink color is due to blood capillaries near its skin and unlike other dolphins they have a hump instead of a fin and a long bottle nose snout instead of a short one. A distinctive characteristic of the pink dolphin is that they can turn their neck 180 degrees due to an unfused vertebra in its neck.

The average pink dolphin is 8.25ft to 9.75ft long (2.5 to 3 meters) and weights 200lbs (90 kilos). Males are usually larger and heavier. Their diet consists of fresh water fish, crustaceans and turtles. The pink dolphin is a solitary creature unlike their more social relative, the tucuxi.

Pink dolphin or bufeo

The giant river otter is considerably larger and heavier than other river otters at over six feet long and an average of 210 pounds. This species of river otters is very social and communicative, they are rarely found alone and communicate through high pitched screeches. They live in groups of five to ten and eat mostly fish.

The giant river otter is a highly endangered animal in the Amazon River, only 2,000 to 5,000 remain in protected areas in the Amazon basin. Its population once extended from Venezuela to Argentina but because of fur hunting and habitat destruction its numbers have dramatically decreased. These mammals can be seen at the Manu National Park and at the Pacaya-Samiria National Reserve.

Amazon giant river otter

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One of the most recognizable Amazon River fish is the piranha. These are small fish with very sharp teeth which local indigenous people use as cutting tools. These small fish are an important part of the Amazon Rivers ecosystem as they eat weak or dead fish and dead animals that would otherwise pollute the waters of the Amazon River. The number of piranha species is estimated to be between 30 and 60. Only five of them pose danger to humans; the red bellied piranha or Pygocentrus nattereri, white piranha or Serrasalmus rhombeus, Serrasalmus Piraya, silver piranha or Serrasalmus Ternetzi and Serrasalmus Hollandi.

Piranhas help keep rivers clean

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The Amazonian manatee is the largest mammal living in the Amazon River at over 1,000 pounds (454 kilos) and 9 feet (3 meters) long. They are found in the northern Amazon River Basin and its tributaries and are locally known as seacows. Their skin is thick, wrinkled and grey in color. The manatee is an herbivore so it depends heavily on vegetation near the rivers, over the years soil erosion from deforestation has been affecting its food supply making it scarcer. During the wet season the manatee can eat up to 110 pounds a day to build up reserves for the dry months.

For centuries the Amazonian manatee has been hunted by local Indians who consumed their meat and used their oil and fat. Demand for the animal expanded making it commercially profitable. Another factor affecting its population is accidentally getting caught in commercial fishing nets. They are classified as vulnerable in the endangered species list.

Amazonian manatee or seacow

The tucuxi is locally known as bufeo gris or bufeo negro. Tucuxi, pronounced too-koo-shee is one of the two species of river dolphin that live in the Amazon River and its tributaries, the other one is the pink dolphin. The tucuxi looks like a bottlenose dolphin with dark gray to light gray coloration but much smaller in size. On average a tucuxi grows between three to five feet long and their weight range is between 95 to 120 pounds. Their diet consists mainly of fish.

Tucuxi, one of the two species of river dolphins in the Amazon River.

The giant Amazon River turtle is also known as Charapa turtle, Arrau turtle, Tartaruga-da-amaznia, or Ara. An adult turtle can grow to more than 3.3 feet (1 meter) in length and they often weight up to 200 pounds, female turtles have a larger shell and are heavier than male turtles. This species of turtles do not leave the water, only females do to lay their eggs on the sandy beaches and immediately return to the water. Once the eggs hatch the hatchlings get the attention of predators, mostly birds, it is believed that only five percent make it to the river. Because of their low survival rate this species has been included in the IUCN Red List of Threatened Species as a conservation dependent species.

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Only five percent of hatchlings will make it to the river.

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Giant Amazon River turtles from the Baltimore National Aquarium.

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The arapaima is locally known as pirarucu or paiche and it is the largest freshwater scaled fish known to humans. It lives exclusively in the Amazon River and its tributaries and can reach a length of over nine feet long (almost 3 meters long) and weight over 440 lbs (200 kg). This species is a favorite among fishermen and have become a victim of overfishing. Because they come to the surface every five to fifteen minutes to breathe in air, they are easy to catch. Fishermen usually use harpoons and nets. Its meat is part of the culinary culture of the Amazon and is sought after for its taste. The arapaima is considered to be a living fossil that has not evolved for more than 20 million years and had no predators other than men.

According the BBC, errors in its classification has pushed the species closer to extinction. The latest taxonomic review was done over 160 years ago. Today they know that there are at least four species of arapaima. While some populations are increasing others are being overfished and driven to extinction.

Arapaima in captivity at the Vancouver Aquarium.

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The electric eel is an electric fish capable of generating electric shocks of up to 600 volts, five times the voltage generated by a U.S. household wall socket. This species live in the muddy waters of the Amazon River and its tributaries and it has a limited vision, therefore heavily relying on its electric field for hunting and self defense. Their bodies contain electrocytes, cells capable of storing power, and when threatened they will discharge electricity making them a feared predator.

The electric eel, despite its appearance, is not truly an eel (Anguilliformes) but a neotropical knifefish. It has a long, cylindrical, serpentine shaped body that grows to an average of 6 to 8 feet (1.8 to 2.5meters) long and weights 44 lbs (20 kilos). The electric eel can live up to 15 years and their diet consists mainly on fish, and in a smaller scale amphibians and birds.

The electric eel is not truly an eel but a neotropical knifefish.

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Dwarf caimans are small crocodile reptiles and are distinguishable by the shape of their head. Their skulls are small and short and their upper jaws overlap the lower. The average length of a dwarf caiman is 5 feet (1.5 meters) long. Its body is covered in hard scales protecting them from predators. Their diet consists of fish and crustaceans. This species is not considered endangered.

The Amazonian dwarf caiman is also known as Cuviers dwarf caiman.

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The green anaconda lives in the shallow waters of the Amazon. It is one of the largest species of snakes and the heaviest known to men. The anaconda can grow up to 30 feet (9 meters) long. Its color, green and brown, serves as camouflage in order to catch its prey. Anacondas are non-venomous constrictor snakes; they wrap around its victim and squeeze them to death. They eat small mammals, fish and rodents.

The green anaconda, a mighty constrictor.

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More than three quarters of the Peruvian territory lies east of the Andes. The jungle or Selva has two parts, the high and the low Selva.

Mining and oil extraction are very controversial economic activities as they bring wealth and economic development but pollute the environment.

In terms of volume, the Amazon is the largest river in the world, it contains one fifth of the earths fresh water.

Between 1890 and 1920 the economy of the region suffer a boom due to the demand for its rubber.

Economic development is taking its toll among native Indians, many of them have fled deep inside the jungle, some have died of starvation and others have adapted to modern live.

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Tags: Amazon basin, Amazon jungle, amazon rainforest, Amazon River, amazon river animals, amazonia, animals of Peru, animals of the amazon river, biodiversity, ecosystem, endangered animals, fauna, flora, indigenous people, Peru, pirahna

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Amazon River Ecosystem and Biodiversity | Discover Peru

Ecosystem – Wikipedia

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

An ecosystem is a community made up of living organisms and nonliving components such as air, water, and mineral soil.[3] Ecosystems can be studied in two different ways. They can be thought of as interdependent collections of plants and animals, or as structured systems and communities governed by general rules.[4] The living (biotic) and non-living (abiotic) components interact through nutrient cycles and energy flows.[5] Ecosystems include interactions among organisms, and between organisms and their environment.[6] Ecosystems can be of any size but each ecosystem has a specific, limited space.[7] Some scientists view the entire planet as one ecosystem.[8]

Energy, water, nitrogen and soil minerals are essential abiotic components of an ecosystem. The energy used by ecosystems comes primarily from the sun, via photosynthesis. Photosynthesis uses energy from the sun and also captures carbon dioxide from the atmosphere. Animals also play an important role in the movement of matter and energy through ecosystems. They influence the amount of plant and microbial biomass that lives in the system. As organic matter dies, carbon is released back into the atmosphere. This process also facilitates nutrient cycling by converting nutrients stored in dead biomass back to a form that can be used again by plants and other microbes.[9]

Ecosystems are controlled by both external and internal factors. External factors such as climate, the parent material that forms the soil, topography and time each affect ecosystems. However, these external factors are not themselves influenced by the ecosystem.[10] Ecosystems are dynamic: they are subject to periodic disturbances and are often in the process of recovering from past disturbances and seeking balance.[11] Internal factors are different: They not only control ecosystem processes but are also controlled by them. Another way of saying this is that internal factors are subject to feedback loops.[10]

Humans operate within ecosystems and can influence both internal and external factors.[10] Global warming is an example of a cumulative effect of human activities. Ecosystems provide benefits, called “ecosystem services”, which people depend on for their livelihood. Ecosystem management is more efficient than trying to manage individual species.

There is no single definition of what constitutes an ecosystem.[4] 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.[12] Other authors have suggested that an ecosystem can encompass a much larger area, even the whole planet.[8] 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.[12] 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.[4]

Ecosystems can be studied in a variety of ways. Those include theoretical studies or more practical studies that monitor specific ecosystems over long periods of time or look at differences between ecosystems to better understand how they work. Some studies involve experimenting with direct manipulation of the ecosystem.[13] Studies can be carried out at a variety of scales, ranging from whole-ecosystem studies to studying microcosms or mesocosms (simplified representations of ecosystems).[14] 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.[15]

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.[16] 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.[17]

Terrestrial ecosystems (found on land) and aquatic ecosystems (found in water) are concepts related to ecosystems. Aquatic ecosystems are split into marine ecosystems and freshwater ecosystems.

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.[10] 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.[10]

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.[10]

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.[10] The introduction of non-native species can cause substantial shifts in ecosystem function.

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.[10] 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.[10] Other factors like disturbance, succession or the types of species present are also internal factors.

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).[18] About 4860% of the GPP is consumed in plant respiration.

The remainder, that portion of GPP that is not used up by respiration, is known as the net primary production (NPP).[19]

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.[19]

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.

In aquatic systems, the proportion of plant biomass that gets consumed by herbivores is much higher.[20]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.[20]

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.[20]

Ecosystem ecology studies “the flow of energy and materials through organisms and the physical environment”. It seeks to understand the processes which govern the stocks of material and energy in ecosystems, and the flow of matter and energy through them. The study of ecosystems can cover 10 orders of magnitude, from the surface layers of rocks to the surface of the planet.[21]

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.[22] Approximately 90% of terrestrial net primary production goes directly from plant to decomposer.[20]

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).[22] 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.[22]

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.[22] 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.[22]

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.[22]

Decomposition rates vary among ecosystems. 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.[23] 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.[23]

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.

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.[24]

Since most terrestrial ecosystems are nitrogen-limited, nitrogen cycling is an important control on ecosystem production.[24]

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.[24] 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.[24] Anthropogenic nitrogen inputs account for about 80% of all nitrogen fluxes in ecosystems.[24]

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.[24] Under nitrogen-rich and oxygen-poor conditions, nitrates and nitrites are converted to nitrogen gas, a process known as denitrification.[24]

Other important nutrients include phosphorus, sulfur, calcium, potassium, magnesium and manganese.[25] Phosphorus enters ecosystems through weathering. As ecosystems age this supply diminishes, making phosphorus-limitation more common in older landscapes (especially in the tropics).[25] 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.[25]

Biodiversity plays an important role in ecosystem functioning.[27] 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.[28] 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.

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.[29] 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.[28]

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.[28] Similarly, an ecosystem engineer is any organism that creates, significantly modifies, maintains or destroys a habitat.

Ecosystems are dynamic entities. They are subject to periodic disturbances and are in the process of recovering from some past disturbance.[11] When a perturbation occurs, an ecoystem 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.[11] Time plays a role in the development of soil from bare rock and the recovery of a community from disturbance.[10]

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.[11] 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.[11]

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”.[30] 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.[11] Disturbance is followed by succession, a “directional change in ecosystem structure and functioning resulting from biotically driven changes in resources supply.”[30]

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.[11] More severe disturbance and more frequent disturbance result in longer recovery times.

Classifying ecosystems into ecologically homogeneous units is an important step towards effective ecosystem management.[31] There is no single, agreed-upon way to do this. A variety of systems exist, based on vegetation cover, remote sensing, and bioclimatic classification systems.[31]

Ecological land classification is a cartographical delineation or regionalisation of distinct ecological areas, identified by their geology, topography, soils, vegetation, climate conditions, living species, habitats, water resources, and sometimes also anthropic factors.[32]

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.[10]

Ecosystems provide a variety of goods and services upon which people depend.[33] Ecosystem goods include the “tangible, material products” of ecosystem processes such as food, construction material, medicinal plants.[34] 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.[33]

Ecosystem services, on the other hand, are generally “improvements in the condition or location of things of value”.[34] 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.[33] While ecosystem goods have traditionally been recognized as being the basis for things of economic value, ecosystem services tend to be taken for granted.[34]

When natural resource management is applied to whole ecosystems, rather than single species, it is termed ecosystem management.[35] Although definitions of ecosystem management abound, there is a common set of principles which underlie these definitions.[36] A fundamental principle is the long-term sustainability of the production of goods and services by the ecosystem;[36] “intergenerational sustainability [is] a precondition for management, not an afterthought”.[33]

While ecosystem management can be used as part of a plan for wilderness conservation, it can also be used in intensively managed ecosystems[33] (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.[37]

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]

The term “ecosystem” was first used in 1935 in a publication by British ecologist Arthur Tansley.[fn 1][38] Tansley devised the concept to draw attention to the importance of transfers of materials between organisms and their environment.[39] 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”.[40] Tansley regarded ecosystems not simply as natural units, but as “mental isolates”.[40] Tansley later defined the spatial extent of ecosystems using the term ecotope.[41]

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.[39]

Read more here:

Ecosystem – Wikipedia

Ecosystem – Wikipedia

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

An ecosystem is a community made up of living organisms and nonliving components such as air, water, and mineral soil.[3] Ecosystems can be studied in two different ways. They can be thought of as interdependent collections of plants and animals, or as structured systems and communities governed by general rules.[4] The living (biotic) and non-living (abiotic) components interact through nutrient cycles and energy flows.[5] Ecosystems include interactions among organisms, and between organisms and their environment.[6] Ecosystems can be of any size but each ecosystem has a specific, limited space.[7] Some scientists view the entire planet as one ecosystem.[8]

Energy, water, nitrogen and soil minerals are essential abiotic components of an ecosystem. The energy used by ecosystems comes primarily from the sun, via photosynthesis. Photosynthesis uses energy from the sun and also captures carbon dioxide from the atmosphere. Animals also play an important role in the movement of matter and energy through ecosystems. They influence the amount of plant and microbial biomass that lives in the system. As organic matter dies, carbon is released back into the atmosphere. This process also facilitates nutrient cycling by converting nutrients stored in dead biomass back to a form that can be used again by plants and other microbes.[9]

Ecosystems are controlled by both external and internal factors. External factors such as climate, the parent material that forms the soil, topography and time each affect ecosystems. However, these external factors are not themselves influenced by the ecosystem.[10] Ecosystems are dynamic: they are subject to periodic disturbances and are often in the process of recovering from past disturbances and seeking balance.[11] Internal factors are different: They not only control ecosystem processes but are also controlled by them. Another way of saying this is that internal factors are subject to feedback loops.[10]

Humans operate within ecosystems and can influence both internal and external factors.[10] Global warming is an example of a cumulative effect of human activities. Ecosystems provide benefits, called “ecosystem services”, which people depend on for their livelihood. Ecosystem management is more efficient than trying to manage individual species.

There is no single definition of what constitutes an ecosystem.[4] 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.[12] Other authors have suggested that an ecosystem can encompass a much larger area, even the whole planet.[8] 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.[12] 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.[4]

Ecosystems can be studied in a variety of ways. Those include theoretical studies or more practical studies that monitor specific ecosystems over long periods of time or look at differences between ecosystems to better understand how they work. Some studies involve experimenting with direct manipulation of the ecosystem.[13] Studies can be carried out at a variety of scales, ranging from whole-ecosystem studies to studying microcosms or mesocosms (simplified representations of ecosystems).[14] 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.[15]

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.[16] 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.[17]

Terrestrial ecosystems (found on land) and aquatic ecosystems (found in water) are concepts related to ecosystems. Aquatic ecosystems are split into marine ecosystems and freshwater ecosystems.

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.[10] 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.[10]

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.[10]

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.[10] The introduction of non-native species can cause substantial shifts in ecosystem function.

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.[10] 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.[10] Other factors like disturbance, succession or the types of species present are also internal factors.

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).[18] About 4860% of the GPP is consumed in plant respiration.

The remainder, that portion of GPP that is not used up by respiration, is known as the net primary production (NPP).[19]

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.[19]

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.

In aquatic systems, the proportion of plant biomass that gets consumed by herbivores is much higher.[20]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.[20]

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.[20]

Ecosystem ecology studies “the flow of energy and materials through organisms and the physical environment”. It seeks to understand the processes which govern the stocks of material and energy in ecosystems, and the flow of matter and energy through them. The study of ecosystems can cover 10 orders of magnitude, from the surface layers of rocks to the surface of the planet.[21]

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.[22] Approximately 90% of terrestrial net primary production goes directly from plant to decomposer.[20]

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).[22] 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.[22]

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.[22] 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.[22]

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.[22]

Decomposition rates vary among ecosystems. 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.[23] 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.[23]

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.

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.[24]

Since most terrestrial ecosystems are nitrogen-limited, nitrogen cycling is an important control on ecosystem production.[24]

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.[24] 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.[24] Anthropogenic nitrogen inputs account for about 80% of all nitrogen fluxes in ecosystems.[24]

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.[24] Under nitrogen-rich and oxygen-poor conditions, nitrates and nitrites are converted to nitrogen gas, a process known as denitrification.[24]

Other important nutrients include phosphorus, sulfur, calcium, potassium, magnesium and manganese.[25] Phosphorus enters ecosystems through weathering. As ecosystems age this supply diminishes, making phosphorus-limitation more common in older landscapes (especially in the tropics).[25] 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.[25]

Biodiversity plays an important role in ecosystem functioning.[27] 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.[28] 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.

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.[29] 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.[28]

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.[28] Similarly, an ecosystem engineer is any organism that creates, significantly modifies, maintains or destroys a habitat.

Ecosystems are dynamic entities. They are subject to periodic disturbances and are in the process of recovering from some past disturbance.[11] When a perturbation occurs, an ecoystem 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.[11] Time plays a role in the development of soil from bare rock and the recovery of a community from disturbance.[10]

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.[11] 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.[11]

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”.[30] 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.[11] Disturbance is followed by succession, a “directional change in ecosystem structure and functioning resulting from biotically driven changes in resources supply.”[30]

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.[11] More severe disturbance and more frequent disturbance result in longer recovery times.

Classifying ecosystems into ecologically homogeneous units is an important step towards effective ecosystem management.[31] There is no single, agreed-upon way to do this. A variety of systems exist, based on vegetation cover, remote sensing, and bioclimatic classification systems.[31]

Ecological land classification is a cartographical delineation or regionalisation of distinct ecological areas, identified by their geology, topography, soils, vegetation, climate conditions, living species, habitats, water resources, and sometimes also anthropic factors.[32]

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.[10]

Ecosystems provide a variety of goods and services upon which people depend.[33] Ecosystem goods include the “tangible, material products” of ecosystem processes such as food, construction material, medicinal plants.[34] 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.[33]

Ecosystem services, on the other hand, are generally “improvements in the condition or location of things of value”.[34] 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.[33] While ecosystem goods have traditionally been recognized as being the basis for things of economic value, ecosystem services tend to be taken for granted.[34]

When natural resource management is applied to whole ecosystems, rather than single species, it is termed ecosystem management.[35] Although definitions of ecosystem management abound, there is a common set of principles which underlie these definitions.[36] A fundamental principle is the long-term sustainability of the production of goods and services by the ecosystem;[36] “intergenerational sustainability [is] a precondition for management, not an afterthought”.[33]

While ecosystem management can be used as part of a plan for wilderness conservation, it can also be used in intensively managed ecosystems[33] (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.[37]

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]

The term “ecosystem” was first used in 1935 in a publication by British ecologist Arthur Tansley.[fn 1][38] Tansley devised the concept to draw attention to the importance of transfers of materials between organisms and their environment.[39] 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”.[40] Tansley regarded ecosystems not simply as natural units, but as “mental isolates”.[40] Tansley later defined the spatial extent of ecosystems using the term ecotope.[41]

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.[39]

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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

A Stem Cell Transplant Let a Wheelchair-Bound Man Dance Again

Stand Up Guy

For 10 years, Roy Palmer had no feeling in his lower extremities. Two days after receiving a stem cell transplant, he cried tears of joy because he could feel a cramp in his leg.

The technical term for the procedure the British man underwent is hematopoietic stem cell transplantation (HSCT). And while risky, it’s offering new hope to people like Palmer, who found himself wheelchair-bound after multiple sclerosis (MS) caused his immune system to attack his nerves’ protective coverings.

Biological Reboot

Ever hear the IT troubleshooting go-to of turning a system off and on again to fix it? The HSCT process is similar, but instead of a computer, doctors attempt to reboot a patient’s immune system.

To do this, they first remove stem cells from the patient’s body. Then the patient undergoes chemotherapy, which kills the rest of their immune system. After that, the doctors use the extracted stem cells to reboot the patient’s immune system.

It took just two days for the treatment to restore some of the feeling in Palmer’s legs. Eventually, he was able to walk on his own and even dance. He told the BBC in a recent interview that he now feels like he has a second chance at life.

“We went on holiday, not so long ago, to Turkey. I walked on the beach,” said Palmer. “Little things like that, people do not realize what it means to me.”

Risk / Reward

Still, HSCT isn’t some miracle cure for MS. Though it worked for Palmer, that’s not always the case, and HSCT can also cause infections and infertility. The National MS Society still considers HSCT to be an experimental treatment, and the Food and Drug Administration has yet to approve the therapy in the U.S.

However, MS affects more than 2.3 million people, and if a stem cell transplant can help even some of those folks the way it helped Palmer, it’s a therapy worth exploring.

READ MORE: Walking Again After Ten Years With MS [BBC]

More on HCST: New Breakthrough Treatment Could “Reverse Disability” for MS Patients

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A Stem Cell Transplant Let a Wheelchair-Bound Man Dance Again

AI Dreamed Up These Nightmare Fuel Halloween Masks

Nightmare Fuel

Someone programmed an AI to dream up Halloween masks, and the results are absolute nightmare fuel. Seriously, just look at some of these things.

“What’s so scary or unsettling about it is that it’s not so detailed that it shows you everything,” said Matt Reed, the creator of the masks, in an interview with New Scientist. “It leaves just enough open for your imagination to connect the dots.”

A selection of masks featured on Reed’s twitter. Credit: Matt Reed/Twitter

Creative Horror

To create the masks, Reed — whose day job is as a technologist at a creative agency called redpepper — fed an open source AI tool 5,000 pictures of Halloween masks he sourced from Google Images. He then instructed the tool to generate its own masks.

The fun and spooky project is yet another sign that AI is coming into its own as a creative tool. Just yesterday, a portrait generated by a similar system fetched more than $400,000 at a prominent British auction house.

And Reed’s masks are evocative. Here at the Byte, if we looked through the peephole and saw one of these on a trick or treater, we might not open our door.

READ MORE: AI Designed These Halloween Masks and They Are Absolutely Terrifying [New Scientist]

More on AI-generated art: Generated Art Will Go on Sale Alongside Human-Made Works This Fall

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AI Dreamed Up These Nightmare Fuel Halloween Masks

Robot Security Guards Will Constantly Nag Spectators at the Tokyo Olympics

Over and Over

“The security robot is patrolling. Ding-ding. Ding-ding. The security robot is patrolling. Ding-ding. Ding-ding.”

That’s what Olympic attendees will hear ad nauseam when they step onto the platforms of Tokyo’s train stations in 2020. The source: Perseusbot, a robot security guard Japanese developers unveiled to the press on Thursday.

Observe and Report

According to reporting by Kyodo News, the purpose of the AI-powered Perseusbot is to lower the burden on the stations’ staff when visitors flood Tokyo during the 2020 Olympics.

The robot is roughly 5.5 feet tall and equipped with security cameras that allow it to note suspicious behaviors, such as signs of violence breaking out or unattended packages, as it autonomous patrols the area. It can then alert security staff to the issues by sending notifications directly to their smart phones.

Prior Prepration

Just like the athletes who will head to Tokyo in 2020, Perseusbot already has a training program in the works — it’ll patrol Tokyo’s Seibu Shinjuku Station from November 26 to 30. This dry run should give the bot’s developers a chance to work out any kinks before 2020.

If all goes as hoped, the bot will be ready to annoy attendees with its incessant chant before the Olympic torch is lit. And, you know, keep everyone safe, too.

READ MORE: Robot Station Security Guard Unveiled Ahead of 2020 Tokyo Olympics [Kyodo News]

More robot security guards: Robot Security Guards Are Just the Beginning

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Robot Security Guards Will Constantly Nag Spectators at the Tokyo Olympics

People Would Rather a Self-Driving Car Kill a Criminal Than a Dog

Snap Decisions

On first glance, a site that collects people’s opinions about whose life an autonomous car should favor doesn’t tell us anything we didn’t already know. But look closer, and you’ll catch a glimpse of humanity’s dark side.

The Moral Machine is an online survey designed by MIT researchers to gauge how the public would want an autonomous car to behave in a scenario in which someone has to die. It asks questions like: “If an autonomous car has to choose between killing a man or a woman, who should it kill? What if the woman is elderly but the man is young?”

Essentially, it’s a 21st century update on the Trolley Problem, an ethical thought experiment no doubt permanently etched into the mind of anyone who’s seen the second season of “The Good Place.”

Ethical Dilemma

The MIT team launched the Moral Machine in 2016, and more than two million people from 233 countries participated in the survey — quite a significant sample size.

On Wednesday, the researchers published the results of the experiment in the journal Nature, and they really aren’t all that surprising: Respondents value the life of a baby over all others, with a female child, male child, and pregnant woman following closely behind. Yawn.

It’s when you look at the other end of the spectrum — the characters survey respondents were least likely to “save” — that you’ll see something startling: Survey respondents would rather the autonomous car kill a human criminal than a dog.

moral machine
Image Credit: MIT

Ugly Reflection

While the team designed the survey to help shape the future of autonomous vehicles, it’s hard not to focus on this troubling valuing of a dog’s life over that of any human, criminal or not. Does this tell us something important about how society views the criminal class? Reveal that we’re all monsters when hidden behind the internet’s cloak of anonymity? Confirm that we really like dogs?

The MIT team doesn’t address any of these questions in their paper, and really, we wouldn’t expect them to — it’s their job to report the survey results, not extrapolate some deeper meaning from them. But whether the Moral Machine informs the future of autonomous vehicles or not, it’s certainly held up a mirror to humanity’s values, and we do not like the reflection we see.

READ MORE: Driverless Cars Should Spare Young People Over Old in Unavoidable Accidents, Massive Survey Finds [Motherboard]

More on the Moral Machine: MIT’s “Moral Machine” Lets You Decide Who Lives & Dies in Self-Driving Car Crashes

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People Would Rather a Self-Driving Car Kill a Criminal Than a Dog

Scientists Say New Material Could Hold up an Actual Space Elevator

Space Elevator

It takes a lot of energy to put stuff in space. That’s why one longtime futurist dream is a “space elevator” — a long cable strung between a geostationary satellite and the Earth that astronauts could use like a dumbwaiter to haul stuff up into orbit.

The problem is that such a system would require an extraordinarily light, strong cable. Now, researchers from Beijing’s Tsinghua University say they’ve developed a carbon nanotube fiber so sturdy and lightweight that it could be used to build an actual space elevator.

Going Up

The researchers published their paper in May, but it’s now garnering the attention of their peers. Some believe the Tsinghua team’s material really could lead to the creation of an elevator that would make it cheaper to move astronauts and materials into space.

“This is a breakthrough,” colleague Wang Changqing, who studies space elevators at Northwestern Polytechnical University, told the South China Morning Post.

Huge If True

There are still countless galling technical problems that need to be overcome before a space elevator would start to look plausible. Wang pointed out that it’d require tens of thousands of kilometers of the new material, for instance, as well as a shield to protect it from space debris.

But the research brings us one step closer to what could be a true game changer: a vastly less expensive way to move people and spacecraft out of Earth’s gravity.

READ MORE: China Has Strongest Fibre That Can Haul 160 Elephants – and a Space Elevator? [South China Morning Post]

More on space elevators: Why Space Elevators Could Be the Future of Space Travel

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Scientists Say New Material Could Hold up an Actual Space Elevator

An AI Conference Refusing a Name Change Highlights a Tech Industry Problem

Name Game

There’s a prominent artificial intelligence conference that goes by the suggestive acronym NIPS, which stands for “Neural Information Processing Systems.”

After receiving complaints that the acronym was alienating to women, the conference’s leadership collected suggestions for a new name via an online poll, according to WIRED. But the conference announced Monday that it would be sticking with NIPS all the same.

Knock It Off

It’s convenient to imagine that this acronym just sort of emerged by coincidence, but let’s not indulge in that particular fantasy.

It’s more likely that tech geeks cackled maniacally when they came up with the acronym, and the refusal to do better even when people looking up the conference in good faith are bombarded with porn is a particularly telling failure of the AI research community.

Small Things Matter

This problem goes far beyond a silly name — women are severely underrepresented in technology research and even more so when it comes to artificial intelligence. And if human decency — comforting those who are regularly alienated by the powers that be — isn’t enough of a reason to challenge the sexist culture embedded in tech research, just think about what we miss out on.

True progress in artificial intelligence cannot happen without a broad range of diverse voices — voices that are silenced by “locker room talk” among an old boy’s club. Otherwise, our technological development will become just as stuck in place as our cultural development often seems to be.

READ MORE: AI RESEARCHERS FIGHT OVER FOUR LETTERS: NIPS [WIRED]

More on Silicon Valley sexism: The Tech Industry’s Gender Problem Isn’t Just Hurting Women

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An AI Conference Refusing a Name Change Highlights a Tech Industry Problem

Scientists Are Hopeful AI Could Help Predict Earthquakes

Quake Rate

Earlier this year, I interviewed U.S. Geological Survey geologist Annemarie Baltay for a story about why it’s incredibly difficult to predict earthquakes.

“We don’t use that ‘p word’ — ‘predict’ — at all,” she told me. “Earthquakes are chaotic. We don’t know when or where they’ll occur.”

Neural Earthwork

That could finally be starting to change, according to a fascinating feature in The New York Times.

By feeding seismic data into a neural network — a type of artificial intelligence that learns to recognize patterns by scrutinizing examples — researchers say they can now predict moments after a quake strikes how far its aftershocks will travel.

And eventually, some believe, they’ll be able to listen to signals from fault lines and predict when an earthquake will strike in the first place.

Future Vision

But like Baltay, some researchers aren’t convinced we’ll ever be able to predict earthquakes.University of Tokyo seismologist Robert Geller told the Times that until an algorithm actually predicts an upcoming quake, he’ll remain skeptical.

“There are no shortcuts,” he said. “If you cannot predict the future, then your hypothesis is wrong.”

READ MORE: A.I. Is Helping Scientist Predict When and Where the Next Big Earthquake Will Be [The New York Times]

More on earthquake AI: A New AI Detected 17 Times More Earthquakes Than Traditional Methods

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Scientists Are Hopeful AI Could Help Predict Earthquakes