Daily Archives: July 5, 2020

Local oil producers are having a hard time keeping up with their regulatory obligations during the pandemic.

Half a dozen companies in Kern County have responded to a state offer by applying for extra time to test oil field injection sites, plug wells, and perform other required health and safety tasks.

Some applicants have received deadline extensions and others haven't. More than a dozen applications are pending.

Oil producers have generally made the case that, although they have been designated critical industries during the pandemic, sharply lower barrel prices have limited their ability to operate as normal.

The Arizona-based Center for Biological Diversity has criticized the state's offer, saying oil companies operators were using the pandemic as an excuse and should not be allowed to set aside their responsibility to protect against pollution.

QUALIFYING CONDITIONS

State Oil and Gas Supervisor Uduak-Joe Ntuk stated in May that to qualify for an extension delays must have been caused by COVID-19 or government orders related to it and that any postponements must "not increase the risk of damage to life, public health, property or natural resources."

"Since all California operators are responding to historically low supply demand, with difficult layoffs and cutbacks," he wrote in a May 1 letter, "CalGEM will consider a one-time, two-month extension in the requirements to submit idle well management plans (IWMP) and fees provided that individual operators demonstrate that this extension will not result in environmental harm."

State records show 39 deadline extension requests were filed with CalGEM, the California Geologic Energy Management Division, between March 23 and June 16. As of Thursday, six have been approved and 18 denied. Two were ruled unnecessary because the operator has the time requested even without asking for it. An additional 13 remained under consideration.

Ntuk said by email Friday, "Each request is unique for each operator and situation. CalGEM is reviewing the submissions and will process them shortly."

In several of the denials, state officials judged the applicants' requests to be beyond the scope of Ntuk's offer, often because the companies asked for more time than he had offered to grant them.

HIGH COSTS

Local oilman Chad Hathaway, who had asked CalGEM for extra time to conduct mechanical testing of his company's injection wells in the Edison Oil Field, said he made the request because doing such work is expensive and requires hiring outside labor at a time he'd rather spend the money keeping his own staff working.

"It requires a workover rig, third party packer service, third party pumping service and about 18 hours worth of labor all of which are third party (not internal employees)," he wrote in an email. "All in all, about $7-10K worth of time and materials. We prefer to keep OUR people working on projects that can support themselves. We cannot afford to hire third party contractors at the moment."

The state didn't grant or deny Hathaway's request. It said he didn't need to do the testing immediately because the wells aren't being used, but that he'll have to complete the work prior to resuming operations there.

MARKET HARDSHIPS

Another local company that filed a request, Bakersfield-based Aera Energy LLC, asked for a 90-day hiatus for its idle-well testing compliance plan because of COVID-19-related market hardships.

Noting its well-testing regimen had been progressing ahead of schedule, Aera wanted to extend a six-year compliance period by four months.

But CalGEM denied the request in a June 19 letter, saying the company had asked for an extension beyond July 1, which Ntuk had disallowed for such cases.

Company spokeswoman Cindy Pollard said it and other California companies are having to cope with COVID-19 and low oil prices. The deadline extension Aera asked for wouldn't have relieved it of CalGEM's oversight or its commitment to health and safety.

"Instead it would have given us a little extra time to meet that compliance, in light of the financial limitations we were experiencing, while continuing to produce the oil our state needs," she said by email. "Aera is especially proud that we were ahead of the States required pace of abandoning idle wells before COVID and we remain committed to meeting the pace outlined in our plan.

OTHER REQUESTS

Other locally operating companies requesting regulatory deadline extensions include California Resources Corp., Chevron, Crimson Resource Management and E&B Natural Resources.

Chevron asked for a one-year deadline extension to abandon or remediate 19 wells that had failed mechanical integrity tests in the Kern River Oil Field.

Making its case in a May 26 letter to CalGEM, Chevron said that "due to the large backlog of remediation work from new UIC regulations and the resource limitations due to COVID-19," the company would miss its deadline for addressing the wells' problems. Chevron couldn't be reached for comment.

State records show the company's request remains under consideration.

E&B requested additional time for a variety of projects including mechanical testing of cyclic steam and steam-flood wells in the Poso Creek Oil Field, testing of water disposal wells elsewhere in Kern, idle-well management work and continuous pressure monitoring at local wells. Some of the requests were denied and some are pending.

Ted Cordova, the Bakersfield-based oil producer's public and governmental affairs director, said by email the requests were intended to "balance the economic forces facing the entire state while still complying with the toughest environmental protections on the planet."

"Our operations have been deemed essential and we are focused on keeping Kern County residents working instead of relying upon public services," he wrote. "Providing flexibility on deadlines ensures that responsible and affordable energy production continues while still protecting the environment and the economy.

Santa Clarita-based CRC is awaiting word from the state on its requests for more time to conduct mechanical testing of injection wells. It said by email it hopes the state will reexamine oil companies' regulatory deadlines.

"CalGEM and other state regulators have chosen not to defer pending regulatory deadlines or new regulations as a general matter and have required specific COVID-19 extension requests," it said.

"While these agencies originally envisioned the COVID-19 hardships ending this month, the increase in COVID-19 cases and the Governors July 1 order make it clear that the pandemic and its effects will be with us for many months to come," it wrote.

Follow John Cox on Twitter: @TheThirdGraf

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Oil producers appeal for time to comply with regulations during pandemic - The Bakersfield Californian

Abstract

Plant economics run on carbon and nutrients instead of money. Leaf strategies aboveground span an economic spectrum from live fast and die young to slow and steady, but the economy defined by root strategies belowground remains unclear. Here, we take a holistic view of the belowground economy and show that root-mycorrhizal collaboration can short circuit a one-dimensional economic spectrum, providing an entire space of economic possibilities. Root trait data from 1810 species across the globe confirm a classical fast-slow conservation gradient but show that most variation is explained by an orthogonal collaboration gradient, ranging from do-it-yourself resource uptake to outsourcing of resource uptake to mycorrhizal fungi. This broadened root economics space provides a solid foundation for predictive understanding of belowground responses to changing environmental conditions.

The diversity of plant traits across the globe shapes ecosystem functioning (1). Seeking general patterns, ecologists have used economic theory to explain trait variation in leaves as the aboveground plant organs for resource acquisition by photosynthesis (13). Aboveground plant strategies thereby fall along a leaf economics spectrum (2) from cheaply constructed but short-lived leaves optimized for fast resource acquisition to more expensive but persistent leaves with a slower rate of return over longer time scale.

Fine roots acquire resources from the soil and are often considered the belowground equivalent of leaves (4). Therefore, fine-root trait variation has been hypothesized to follow a similar one-dimensional spectrum (1, 5). At one side of this spectrum, plants with a fast belowground resource acquisition strategy are expected to construct long, narrow-diameter roots with minimal biomass investment but high metabolic rates (1, 4, 6). At the opposite side of the spectrum, plants with a slow strategy are expected to achieve longer life span and prolonged return on investment by constructing thicker-diameter, denser roots (4, 7).

However, mixed empirical results caused ecologists to question whether variation in root traits can be adequately explained by a one-dimensional fast-slow economics spectrum (1, 5, 810). Instead, when taken together, earlier results reveal that root trait variation might be driven by multiple evolutionary pressures (8, 1114). Here, we aim to settle this debate by presenting a new conceptual framework of root economics that better captures the complexity of belowground resource acquisition strategies. First, we integrated existing knowledge to build a conceptual understanding of the covariation among four key root traits (Table 1 and Fig. 1). Second, we tested our conceptual model against root traits of 1810 plant species from a global database. Third, we investigated generality of the concept across all biomes of the world, different plant growth forms, and symbiotic partnerships. All analyses were phylogenetically informed using fine-root trait data from the Global Root Trait (GRooT) database (15).

Expected correlations are based on mathematical and ecological rationale and empirical support from the literature. De facto correlations (see also fig. S1) are phylogenetically informed correlation coefficients of species subsets with the respective trait coverage. D, root diameter; SRL, specific root length; RTD, root tissue density; N, root nitrogen content; CF, cortex fraction.

On the basis of this concept, we hypothesize (i) a collaboration gradient ranging from do-it-yourself soil exploration by high specific root length (SRL) to outsourcing by investing carbon into the mycorrhizal partner and hence extraradical hypheae, which requires a large cortex fraction (CF) and root diameter (D) and (ii) a conservation gradient ranging from roots with high root tissue density (RTD) that show a slow resource return on investment but are long-lived and well-protected, to fast roots with a high nitrogen content (N) and metabolic rate for fast resource return on investment but a short life span. Arrows indicate negative correlations between the single traits (see Table 1).

The currency of root economics is the carbon input required to construct fine roots that explore the soil for resource acquisition. Specific root length (SRL)the root length per unit masstherefore reflects the rate of return per unit of investment and is a function of both root diameter (D) and root tissue density (RTD)the root mass per unit of root volumefollowingSRL=4/(D2RTD)Although this equation (6) is a simplification when sampling heterogeneous fine-root populations (16), it implies that SRL increases with decreasing D and/or RTD. Besides efficient soil exploration, plants have to maintain a high metabolic rate to assure fast resource acquisition leading to high nitrogen content (N) in the fine roots (1, 17). While strong negative relationships between SRL and D (9, 14, 1820) and between RTD and N (9, 14, 19) have been observed, the relationships between SRL and RTD (19, 21, 22) and between D and N (10) have been less clear. In fact, observations across a wide range of species suggest that plants can construct roots with many combinations of SRL and RTD (9, 14), indicating complex trait interactions inconsistent with a one-dimensional root economics spectrum (811, 14).

A growing body of literature (8, 1114) indicates that this root trait complexity may result from the range of belowground resource uptake strategies. In contrast to aboveground photosynthesis, which is solely conducted by plant organs, belowground many species have the ability to outsource resource acquisition. This gradient of plant collaboration strategies ranges from do-it-yourself acquisition by cheap roots for efficient soil exploration to outsourcing acquisition via the investment of carbon in a mycorrhizal fungal partner for the return of limiting resources. However, these outsourcing strategies have consequences for root traits. This is particularly true for arbuscular mycorrhizal fungi (AMF) because plants must increase their root cortical area, and hence their D, to provide the intraradical habitat for their fungal partner (19, 23, 24). This is generalizable for plant symbiosis with AMF, the most widespread type of mycorrhizal fungi (24) and also well documented for ectomycorrhizal (EM) fungi (25). Using this body of literature as our foundation, we developed an overarching concept of root economics based on the understanding that plants can optimize resource uptake by investing carbon either in thin roots that efficiently explore the soil themselves (14) or in a mycorrhizal fungal partner, which often requires a thick root for efficient symbiosis (Fig. 1).

This conceptualized collaboration gradient from do-it-yourself to outsourcing challenges the traditional spectrum of root economics that assumes D to increase with RTD for tissue conservation. Both scaling laws and empirical data (22) show that as D increases, root cortex area increases at a faster rate than stele area such that D scales positively with the cortex fraction (CF) (19) [although patterns can vary among growth forms (10)]. The parenchymatous cortical tissue has a lower carbon content and dry weight than the stele tissue, which transports nutrients and water through lignified cells (26, 27). Thus, CF and RTD will be negatively correlated (Table 1). Furthermore, since D and CF are closely positively correlated and increase in unison with mycorrhizal symbiosis, D should be negatively correlated with RTD. These relationships contradict the assumption of a one-dimensional root economics spectrum, where plants with a slow strategy are expected to construct roots that are both thick and dense, and advocate for a multidimensional space of root trait variation.

By testing pairwise correlations of all traits, we confirmed the bivariate relationships underlying our new concept of a belowground economics trait space with two main dimensions (Table 1). The strongest negative correlation was found between SRL and D (R = 0.70), representing the collaboration gradient from do-it-yourself to outsourcing. We also found a negative correlation between RTD and root N (R = 0.26) as observed in previous studies (9, 14, 19), which corresponds to a conservation gradient, representing the traditional trade-off between fast and slow return on investment (Fig. 1).

On a subset of 748 species with complete information on the four main root traits (SRL, D, RTD, and root N), we could confirm these two distinct and largely independent gradients in a phylogenetically informed principal component analysis (PCA) where the first two axes encompass a plane with a cumulative explanatory power of 77% of all root trait variation. Henceforth, we refer to these gradients as the main dimensions of the root economics space (Fig. 2A). The first PCA axis (44% of total trait variation) represents a gradient from SRL to D, confirming our conceptualized collaboration gradient and suggesting that it actually represents the main source of root trait variation. The second PCA axis (33% of total trait variation) represents the conservation gradient from root N to RTD (table S1).

Phylogenetically informed principal component analyses (PCAs) of core traits of (A) 748 global species, (B) 621 arbuscular mycorrhizal (AM) species (blue), and (C) 94 ectomycorrhizal (EM) species (red). NM, nonmycorrhizal. The collaboration gradient (44%) ranges from do-it-yourself roots with high SRL to outsourcing roots with thick diameters (D). The conservation gradient (33%) ranges from fast (N) to slow (RTD). For each corner of the root economics space, in (A) we highlight two representative plant species: QV, Quercus virginiana Mill.; CH, Carex humilis Leyss.; CO, Cornus officinalis Siebold & Zucc.; ZM, Zea mays L.; LP, Lathyrus pratensis L.; GB, Ginkgo biloba L.; BL, Betula lenta L.; CP, Cardamine pratensis L. (D) Woody (ocher) and nonwoody (green) species show no distinct pattern within the root economics space (see fig. S4 and table S4). (E) PCA based on bivariate trait relationships. The percentage mycorrhizal colonization (%M) and the CF are positively correlated with D along the collaboration gradient, while root life span is negatively correlated with N along the conservation gradient. See table S1 for PCA scores.

Species associated with AMF were the largest group in the database and were distributed over the entire trait space (Fig. 2A) but differed significantly from both nonmycorrhizal (NM) and EM species (table S4). NM plants aggregated on the do-it-yourself side of the collaboration gradient and on the slow side of the conservation gradient. EM plants showed less variation along the collaboration gradient than AM plants with a tendency toward do-it-yourself and slow as well. A high RTD, indicative of a slow strategy, might partly originate from the fact that EM species are often woody (28) or it might reflect a general slow nutrient cycling in ecosystems dominated by EM species (29, 30). The tendency for EM plants toward do-it-yourself roots with high SRL likely results not only from the nature of the EM symbiosis that is less dependent on cortex area but also from its more recent evolution, as evolutionarily younger species tend to have thinner roots (14, 23, 27, 31). Even so, PCAs that solely represent the root traits of either AM or EM plant species (Fig. 2, B and C, and table S1) show the same dimensions of variation as in the global dataset, highlighting the existence of the same trade-offs within each mycorrhizal type.

Plant species associated with N2-fixing bacteria differed from other species (table S4) by being located on the fast side of the conservation gradient as their roots are rich in N (fig. S2A). Nevertheless, we could still confirm the collaboration gradient as the first PCA axis within this species set (fig. S2, B and C, and table S1). The importance of the collaboration gradient within N2-fixing species might derive from the large P demands of plants associated with N2-fixing bacteria, which leads to either high mycorrhizal dependency or alternative do-it-yourself strategies like cluster roots (24). Investigating different plant growth forms, we found that woody plants span a wider range of variation than nonwoody plants within the global trait space (Fig. 2 and table S4). Still, the two gradients of the root economics space exist within both woody and nonwoody plants (fig S4), indicating that there is wide variation and very similar trade-offs operating irrespective of growth form. Last, the two dimensions of the root economics space are present irrespective of biome (Fig. 3 and table S1), which did not differ from each other in their location within the global trait space (table S4).

Root traits and trait relations are known to vary across biomes (14). We found no respective between group variation within the root economics space (table S4). Still, to test whether the concept is broadly generalizable, we present separate PCAs for biomes spanning arid to tropical. We found that the root economics space was apparent in all of the biomes represented by our species (panels A, B, C, and D). In continental systems, the conservation gradient was represented by principal component 3 (D) instead of principal component 2 (E). See table S1 for principal component analyses. pc, principal component.

To confirm our ecological interpretation of the proposed gradients, we added traits to the PCA that act as proxies for ecological functions (Fig. 2E and table S2). We used percent root length colonized by AMF (%M) as a proxy for the strength of the mycorrhizal symbiosis (32) and CF as a general proxy for the ability of a species to host mycorrhizal fungi (19, 33, 34). We found both %M and CF to be associated with the outsourcing side of the collaboration gradient. To test whether the proposed conservation gradient aligns with the classical fast-slow economics spectrum, we used root life span as a proxy for short- or long-term investment of plant carbon (1, 3537). We found that longer life span was indeed associated with the slow side of the conservation gradient, which is consistent with reports of negative relationships between root life span and N (1, 35, 37).

The decrease in D over evolutionary time (14, 31) suggests a reduced dependence of plants on mycorrhizal fungi. We found that the collaboration gradient was indeed phylogenetically conserved, showing an evolutionary transition from outsourcing to do-it-yourself (Fig. 4 and tables S3 and S5). In contrast, the fast-slow trade-off of the conservation gradient was less pronounced across all plant families in our database (Fig. 4) and also less phylogenetically conserved (table S3). Terrestrial plants coevolved with AMF, causing the mycorrhizal symbiosis to be evolutionarily stable (38, 39). This might explain the finding that the consequences for root morphology and anatomybeing associated with the collaboration gradientare phylogenetically conserved at high levels. Different explanations have been proposed as to why D gradually decreased with evolutionary time, including a decline in atmospheric CO2 (13), leading to higher water demands and a reduction in the dependence on mycorrhizal fungi (14). Remarkably, this trend very rarely resulted in a complete loss of the mycorrhizal symbiosis but instead led to varying degrees of outsourcing. Following this line of reasoning, evolutionary history might be the reason why the collaboration gradient is the main source of variation in root traits. As the ability to outsource is a major difference between above- and belowground economics, the importance of the collaboration gradient might be the key to explaining decoupling of root and leaf traits, leading to inconsistencies within the plant economics spectrum found in the past (9, 11, 27, 40).

On the left, we display the phylogenetic tree of 1810 species aggregated at a family level with the standardized family mean trait values of the four core traits (center) ranging from low (yellow) to medium (green) to high (blue). The collaboration gradient shows a strong phylogenetic pattern ( = 0.8, P < 0.001) with a transition from families with thick D to those with high SRL. The phylogenetic signal in the conservation gradient is less pronounced ( = 0.5, P < 0.001), although still significant (see also table S3). For detailed information about specific clades, see table S5, and for family distribution across clades, see table S6. Pie charts (right) depict the fraction of different mycorrhizal association types within the broader plant phylogenetic clades (indicated by corresponding background colors).

Together, we provide a conceptual framework explaining the mechanistic basis behind root trait covariation and show its ubiquity across biomes, growth forms, and symbiotic partnerships. The root economics space synthesizes recent evidence to illustrate why root trait variation cannot be adequately explained by a one-dimensional spectrum (8, 9, 11, 14, 19, 41). Plant outsourcing of belowground resource acquisition through collaboration with mycorrhizal fungal partners is not just an extra dimension in the root economics space but rather is the main dimension of root trait variation, which is fundamentally different from the aboveground economy. This collaboration gradient from do-it-yourself to outsourcing represents an investment in soil exploration by either the root itself or its mycorrhizal fungal partners. It is independent from the conservation gradient, which represents the well-known concept of fast versus slow return on investment. Thus, both gradients depict different facets of root economics and, rather than a single one-dimensional spectrum, encompass a whole root economics space of plant strategies for belowground resource acquisition.

All analyses presented here are based on the GRooT database (15). The GRooT database combines root trait observations from the Fine-Root Ecology Database (FRED) (42) and TRY (43) with additional datasets providing data measured on individual plants for which taxonomical information is available. It includes data on both coarse and fine roots. For the objective of this study, we selected fine roots only, as coarse roots are usually not absorptive and therefore less relevant in the context of root economics (42, 44). We treated roots as fine roots if they met at least one of the following criteria: (i) they were of root orders 1 to 3, (ii) they were classified as fine roots by the initial authors, or (iii) their diameter was smaller than 2 mm. Data measured on dead roots were excluded from the analyses. Furthermore, we excluded ferns (Polypodiopsida) because of their very special root morphology that is hardly comparable with vascular plants (45, 46). We only selected data where species-level information was available. During the past decade, a set of root traits was found to be highly informative of root economics: SRL, D, RTD, and root N (811, 14, 20, 27). Hence, we focused our main analyses on those four traits. In addition, we analyzed the percentage of root length colonized by mycorrhizal fungi (%M) while > 99 % of these data refer to arbuscular mycorrhizal colonization - and the root area occupied by the cortex, i.e., CF as proxies for the strength of mycorrhizal symbiosis, as well as mean root life span. We checked the values of these traits for outliers and excluded values of RTD exceeding 1.0 in further analyses.

Categorical data from GRooT such as main biome type (tropical, temperate, continental, arid, or polar) following the Kppen-Geiger classification, plant woodiness (woody, nonwoody, or facultatively woody), mycorrhizal association (NM, arbuscular mycorrhiza, ectomycorrhiza, or other (e.g., ericoid mycorrhiza), and nitrogen-fixing ability (fixers or nonfixers) were used in the downstream analysis and testing of our conceptual framework. GRooT includes mycorrhizal association data from FungalRoot (47), which did not cover our entire species set. To achieve full data cover, we filled the gaps and did minor annotations based on the following general rules:

(i)Mycorrhizal association is constant within species, hence excluding a facultative mycorrhizal type. In cases where a lack of mycorrhizal colonization has been reported only under specific environmental conditions less suitable for the mycorrhizal symbiosis, we assigned the species as mycorrhizal, while in cases with intraradical hyphae but no evidence for a symbiotic interface, we assigned species to be NM.

(ii)Almost all plants have one type of mycorrhizal association as the dominant one. Therefore, dual mycorrhizal association was only assigned if species show no clear dominance toward one type.

(iii)The mycorrhizal association type is usually constant within a monophyletic genus and often within a family (24, 47, 48). Therefore, we filled remaining gaps with the respective mycorrhizal association type of sister species.

All data processing and analyses were done using R 3.6.1 (49). In this study, we analyzed how different root traits are related to each other at the level of plant species; hence, a first step was to calculate species mean values. As root traits were measured in different studies varying in design (e.g., on in situ grown plants versus plants growing in pots), and because most traits varied several orders of magnitude, several steps of data processing were required before calculating species mean trait values. First, to obtain normal distributions, we log-transformed each trait, except for %M and CF, which were scaled to the range of 0 to 1 and arcsine square root transformed. We then Z transformed each trait to a mean of 0 and an SD of 1 to assure variance homogeneity. Furthermore, we corrected for main study design (measurements on plants in situ, in pots, or hydroponics) and the publication in which the trait measurements were first reported (as a proxy for other study specific factors, e.g., plant age, soil conditions, or sample handling). This was done by building a linear mixed model for each trait, where the trait was treated as the response variable, study design as a fixed factor, and publication as random factor. We used residuals of these models in further analyses.

Within some species, the categorical traits woodiness and biome had different data entries (e.g., because the species occurs both in temperate and continental biomes). In those cases, we categorized the species in the biome in which it had most observations, and we categorized its woodiness by its most commonly observed entry in further analyses.

In total, we analyzed information of 1547, 1662, 1361, and 1158 species for D, SRL, RTD, and N, respectively. Scientific names in GRooT are standardized among datasets and brought up to date by querying species names using the Taxonomic Name Resolution Service v4.0 (http://tnrs.iplantcollaborative.org/) (50). We constructed a phylogenetic tree including all species using the backbone phylogeny from Zanne et al. (51) and adding additional missing species with the function add.tips from the package phangorn (52). We calculated Pagels using the package picante and evaluated the strength of the phylogenetic signal for each trait; a large (close to the upper bound of 1.0) Pagels value indicates higher phylogenetic conservatism (53), whereas a low (close to 0.0) value indicates a lack of phylogenetic conservatism.

As all traits exerted strong phylogenetic signal (table S3), we used phylogenetically informed methods for all analyses. We first assessed bivariate relationships between the four core traits (D, SRL, RTD, and N) and CF to build our conceptual framework (Table 1 and Fig. 1), and we also tested for relationships of these traits with %M and root life span (fig. S1). Sample sizes varied for these bivariate correlations, depending on the number of species with complete information for both involved traits, and ranged from 19 (for the correlation between %M and root life span) to 1402 (for the correlation between D and SRL) (fig. S1). In total, we used 1810 species for these bivariate correlations. We fit phylogenetic generalized least square models using the pgls function in the R package caper (54, 55) to each pair of traits to conduct phylogenetically corrected regression analyses. Phylogenetically corrected correlation coefficients (r values) were then calculated by taking the square root of the adjusted model r2 and by multiplying this with 1 if the regression coefficient was negative. In cases where the adjusted model r2 was negative, we assigned an r coefficient of 0.

We used phylogenetically informed PCA to identify main dimensions of variation among root economic traits. A phylogenetic PCA was performed for the four core traits D, SRL, RTD, and N using the phyl.pca function of the phytools package (56). There were 748 species that had complete data for these four core traits. The eigenanalysis uses the correlation structure of the phylogeny to inform its estimates of eigenvalues and eigenvectors (56, 57). To assess whether the PCA results and hence the dimensions of the root economics space were sensitive to biome type, mycorrhizal association, woodiness, or nitrogen-fixing ability, we repeated the above analysis for subsets of different biomes [tropics, temperate, continental, and aridthe polar biome was represented by too few species (n = 5) to perform a reliable analysis], mycorrhizal association type (arbuscular mycorrhiza versus ectomycorrhiza), woodiness (woody versus nonwoody), and nitrogen-fixing ability (present or absent).

We assessed whether roots from species with different mycorrhizal associations (arbuscular mycorrhiza, ectomycorrhiza, arbuscular mycorrhiza, and ectomycorrhiza, i.e., intraspecific variation in mycorrhizal association type, ericoid mycorrhiza, and nonmycorrhiza associated), species from different biomes (temperate, tropical, arid, and continental), woody or nonwoody species, and species that either did or did not associate with bacteria able to fix nitrogen, differed significantly from each other in the global multidimensional PCA space, i.e., in their first two PCA axes (which jointly explained 77% of all trait variation). This was done using a permutational multiple analysis of variance, in which the first two PCA axes were treated as the response variables and mycorrhizal association type, biome, woodiness, or ability to fix nitrogen as the fixed factor. We used Euclidean pairwise distances in PCA space among species and calculated 999 permutations using the pairwise.adonis function in the pairwiseAdonis package (58). To test for the significance of differences between different categories of mycorrhizal associations and biomes, we used false discovery rates (59) to reduce the likelihood of type I errors due to multiple testing.

Furthermore, we investigated multivariate trait space for seven traits, i.e., the four core traits from the above-described PCAs (D, SRL, RTD, and N) supplemented by three additional traits: CF, %M, and root life span. Observation-based PCA requires each replicate (species) to have complete data for all traits, but there were few species with a complete set of all seven traits. Therefore, we performed an alternative dimensionality reduction analysis based on pairwise correlations between traits. For this analysis, we computed phylogenetically informed pairwise correlations between each of the 21 trait combinations, where each trait combination included a slightly different set of species for which traits were available (fig. S1). We then performed a standard eigenanalysis on this positive definite matrix of phylogenetic correlation coefficients (60).

Visual examination of the distribution of traits across the phylogeny was obtained using the function phylo.heatmap in the package phytools (56). We further examined the phylogenetic trends observed across broader phylogenetic clades of seed plants using a randomization test to quantitatively compare individual clade trait values to the rest of the phylogeny. The test determines whether the mean trait value observed in a clade deviates significantly from the population mean under the null hypothesis that the trait has a random phylogenetic distribution. To do so, we created an algorithm in R that selected clades sequentially at each node. Because of the large number of species, we selected particular nodes that enveloped important phylogenetic clades with at least 30 species (tree tips) included. For each clade, we calculated the observed mean and kurtosis values as measures of central tendency and dispersion values within clades, respectively. Then, we generated a series of 999 random values shuffling trait values among the tips of the original tree. Significance was calculated after estimating if the observed clade mean or kurtosis were outside the 95% confidence intervals of the clade estimations using the randomized datasets. In the case of the kurtosis, values higher than the randomized mean were interpreted as evidence of underdispersion in the clade (leptokurtic distribution), whereas lower values were considered sign of overdispersion (platykurtic distribution).

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See the original post here:

The fungal collaboration gradient dominates the root economics space in plants - Science Advances

Years after our popular Where Are They Now: Local Media series, weve decided to revisit the concept with former elected officials in and around Traverse City to find out what theyve been doing since they left office.

Mike Estes served as Traverse City mayor from 2007 to 2009 and again from 2011 to 2015. He owns several tree farm parcels, where he works to remove invasive species such as autumn olive and replace them with native trees. Its mostly hardwoods, he says. Things have gone very well. I have time to work on the properties and trees. Once hes removed the non-native plants, he sells the parcels, then does it again elsewhere.

Estes serves on the Northwestern Michigan College Board of Trustees and runs his own private equity firm. In the last few years, he says he has significantly cut back on the time for the latter. Thats because he has chosen to spend more time with his family and in the great outdoors. I have six grandchildren. Now I have time to see them. I spend more time boating and fishing part of my passion is hunting and fishing.

Jason Allen is now Michigans state director of the USDA Rural Development. He seved as a member of the Michigan House of Representatives for the 104th District from 1999 to 2002.He was elected to the Michigan Senate in November 2002, and was re-elected in November 2006.He sought the Republican nomination for Congress in the 2010 primary, losing by 15 votes to Dan Benishek. He was asked by former Governor Snyder to serve as a policy advisor for the states Veterans Affairs Agency, then ran in 2016 to succeed the retiring Benishekand was defeated in the primary by Jack Bergman.

Today, as the state director for Rural Development, he leads a team of professionals across the state: USDA Rural Development provides loans and grants to help expand economic opportunities and create jobs in rural areas, including infrastructure improvements, business development, community services such as schools, public safety and health care, and high-speed internet access.Among the projects Allen has helped spearhead: a current project in Benzonia replacing two miles of US-31 along with all-new curb and gutters, sidewalk repairs and ramp upgrades and sewer structures; a new road commission building in Mt. Pleasant; and a new jail in Escanaba.

Rural development also directs housing programs and Allen works to provide access to high-speed fiber networks for internet access in rural areas.

And he still works from time to time at Captains Quarters, the downtown Traverse City haberdashery owned by his father, Maurie Allen. I still have a key. For street sales, its all hands on deck, he says.

Michelle McManus is a vice president at Fifth Third Private Bank in Traverse City. She served in the state House of Representatives 1993-1999 and in the Michigan State Senate from 2003 to 2010. She left both positions after being term-limited. She said she chose not to pursue further office or working elsewhere in government or lobbying. At that point my daughter was in seventh or eighth grade and I had a little boy. I felt it was time to make a change, she says.

Though she had not previously considered a career in the field, her work on committees for appropriations and finance led her in that direction. I thought it would be an interesting career, she says. Shes since worked in various capacities at both Fifth Third and Honor Bank. I get to work with families and help them with their financial goals and needs. Its similar to working with constituents. I always said when I was a commercial lender it is like passing a bill: You find the loan or opportunity for a bill, draft it, then take it to committee. Then it gets passed or vetoed.

Best of all? I never left northern Michigan, she says.

From 1993 to 2011, Bart Stupak was the Democratic congressman representing Michigans 1st District, including northwestern lower Michigan and the upper peninsula. He chose not to run in 2010, and said he had no real plan when he left office. Then Harvard came calling. Harvard offered a fellowship. I held weekly seminars, he says, discussing issues with students and other fellows.

Stupak has since joined the Washington, D.C. law firm Venable LLC, where he focuses on healthcare system financial restructuring and also serves as a lobbyist. Though based in D.C., he says most of his clients are from Michigan. Stupak says the most rewarding part of his job is the pro bono work he and the firm do, much of which is for homeless and disabled persons. Its challenging, he says, particularly when people have no fixed address.

The pandemic has been a challenge as well. Hes working from his home just outside Escanaba. I left March 16, and thought Id be back in a week. I left things on the edge of my desk, now I have to try to recreate files, Stupak says.

Linda Smyka was mayor of Traverse City in 2000 and again from 2003-2005. She says she has dedicated much of the time since to her family. Weve been raising our now 14-year-old granddaughter, so its been a busy life, she says. While shes worked with various community groups, including her longtime stint as a member of the Womens Resource Center Board of Directors, the pandemic gave her a new role: teacher. Ive had a refresher course in algebra. Its a whole new ballgame, she says with a laugh.

Its all about her family. That includes working with her husband, Stanley Smyka, at his dental office. The biggest thing on the horizon now is an upcoming move from Traverse City to Kingsley, where their granddaughter Mia just completed her freshman year. The move will be huge. Ive lived in my current home for 20 years, she says.

Dan Scripps was appointed by Governor Gretchen Whitmer to the Michigan Public Service Commission in 2019. A decade ago, Scrippsserved one term representing Benzie, Leelanau, Manistee, and Mason counties in the Michigan House of Representatives. After losing his reelection bid in 2010 to Ray Franz, he ran again in 2015, losing to Curt Vanderwall.

He subsequently served as president of the Michigan Energy Innovation Business Council and Institute for Energy Innovation,as a vice president with Advanced Energy Economy, and as the Energy Foundations midwest policy program director for 13 states. He also practiced law in Washington D.C., again working primarily on issues regarding energy.

Today, Scripps again lives with his family in his hometown of Northport, where his oldest is in school. His wife works from home, while he commutes back and forth to Lansing or did until the pandemic hit. There have been lots of phone calls and video calls, he says. When (new) normal circumstances return, he will be commuting again, including going back and forth to the Upper Peninsula, where he has been appointed to the UP Energy Task Force.

Howard Walker left office in 2013 after choosing not to run for a second term as state senator. Hed earlier served three terms as a state House representative. He said he enjoyed his time in the legislature, but eventually decided he wanted to spend more time with his family. The work was very meaningful and exciting. I miss it, but family was more important, he says. I wanted to reconnect with my family and spend more time being a dad.

He previously owned a surveying company, and still has his surveying license as well as a real estate license, but hes spent of his time around the house working on the house. I enjoyed carpentry and manual labor. Its good for you physically, he says.

After improving their home on Old Mission Peninsula, he and his wife Dianne moved to Elk Rapids. We wanted to downsize. We love it, he says.PHOTO (top row): Estes, McManus, Scripps; (middle) Stupak; (bottom): Allen, Smyka, Walker

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Where Are They Now: Local Politicians - Traverse City Ticker

By MONITOR TEAM

One of the big questions sparked by the coronavirus crisis is: How do communities and societies best navigate a fast-changing and unpredictable world faced with multiple crises around climate, environment and health?

These challenges can be local, regional or global, and are worth examining to understand how different communities confront them. Scientists working on the Rights and Resilience (RARE) research project have been studying the responses of the Maasai of southeastern Kenya to these crises.

Many segments of the population at the local level in Kenya are currently struggling with three intertwined crises: Climate change, locusts and the coronavirus disease (Covid-19).

Climate change is a global phenomenon that is characterised by a general rise in the temperatures of the earth surface and the sea as a result of humans emitting greenhouse gases into the atmosphere.

Climate change is particularly concerning because it is believed to be a precursor to numerous problems such as droughts, floods, declining farm yields, and increasing water scarcity. It is an overbearing threat to human lives and livelihoods.

Long before climate change became a modern-time human concern, desert locusts had been known to ravage Africa. Swarms of billions of insects can eat away thousands of hectares of croplands and other green vegetation, leading to problems such as food insecurity and scarcity of livestock fodder.The destruction may also cause landscape changes that could lead to conflicts over natural resources.In recent times, the world has been attacked by coronaviruses: the SARS Coronavirus (SARS-Cov) that led to the Severe Acute Respiratory Syndrome in November 2002; the MERS Coronavirus (MERS-Cov) that caused Middle East Respiratory Syndrome in September 2012; and the novel SARS Coronavirus-2 (SARS-COV-2) that was first identified in December 2019 in Chinas Wuhan City and is responsible for the Coronavirus disease-19 (Covid-19) pandemic.

These are some of several other coronaviruses that have potential to attack and sicken humans.

SARS-Cov reportedly disappeared in 2004 while MERS-Cov continues to make sporadic but localised attacks around the world.

ImpactOf the coronavirus attacks, the ongoing SARS-COV-2 has had the most impact in terms of geographic coverage, number of humans infected, and deaths.Like a colossus, it has literally spread across the world, threatening whole economies, lives and livelihoods. Some analysts argue that its effects may also inevitably impact world politics and peace.

The big question is: How do people get around a crisis that is characterised by combined attacks from climate change, locust infestation and coronavirus? This has been the situation in some parts of Kenya since the outbreak of Covid-19 in December 2019 at a time when the country was already facing climate-induced floods and swarms of locusts.

The Rights and Resilience (RARE) research project has followed up on how Kenyan pastoralists handle such a complex situation.

Among others, the study has focused on the Maasai, the world-renowned cattle herders whose rustic lifestyles are often portrayed on film and television in a romantic light. In fact, the Maasai are active participants in modern society, and are trying to cope with the challenges (such as a changing environment) of the modern economy while maintaining their cattle culture and lifestyle.

Climate change poses a major challenge for the Maasai due to their herding economy that thrives largely on stock mobility to reach seasonal pasturelands.

As Kenyas climate becomes more unpredictable, with frequent droughts and more intense floods, the Maasai are constantly grappling with the question of how their cattle, goats and sheep can get enough fodder and water.

Their households also need adequate food to get them through seasons whose impacts they can hardly envisage. Drought-flood cycles have meant that crops rot and the livestock get more diseases during flooding; and households run out of food and herds get decimated due to shortage of fodder in times of drought.

There is also a whole issue around intergenerational change. While older Maasai folks have held onto their herding culture despite challenges such as climate change, the younger generation seems to be attracted to trappings of the modern market economy.

Though many may not completely abandon herding entirely, Maasai youth are increasingly pulled towards the perceived comfort of city life, and given a chance they would probably not hesitate to convert most livestock assets into other holdings that are compatible with city life.

Climate change is therefore impacting not only the Maasai lifestyle but also individual mindsets, with probable far-reaching consequences.

On March 13, Kenya announced the first coronavirus infection in the country. At the time, Maasai land was also experiencing heavy rains (and associated floods) as well as one of the worst locust infestations that had been ravaging much of eastern Africa since 2019.

While floods cause crops on the fields to rot, locusts often destroy vegetation that livestock consume as fodder. This means that post-locust seasons are characterized by fodder scarcity and Maasai herds could starve at a time when there may also be disease outbreaks.

Drought-flood cycles are linked to climate change, but the connection with locust infestations is still unclear even though both events contribute significantly to food insecurity among the Maasai.

An outbreak of diseases like Covid-19 necessitates urgent government measures to protect people and the economy, but such actions could alter the survival equation for the Maasai in many ways.

One such measure is restricted movement of people that comes in the form of curfews and lockdowns. For the Maasai herder who needs mobility to access distant pastures, these measures disrupt movement (which usually occurs many times at night) and failure to reach pasture and water at the right time.

It may mean a lack of adequate time to reach a fellow Maasai age mates kraal to spend a night and access important services like food and drinking water. Further, it may even mean that pasture and water reconnaissance groups that go ahead of migrating herds take long to send back reports, thereby putting herd movement in jeopardy.Other actions

Other actions like closure of livestock markets depress household incomes, which may cause families to sell their livestock on informal markets at lower prices, thus growing poorer. Curfews and lockdowns may also put enormous pressure on herders, especially from their families back home.

On the whole, official measures to control Covid-19 may only exacerbate an already dire situation, especially in instances where multiple events such as climate change, locust infestation and coronavirus disease act together.

So how are the Maasai herders handling such a disastrous complex situation? As specialists in dealing with crises and unpredictability, cattle keepers are meeting the new challenges creatively by drawing on three basic strategies: mobility, diversification and adopting new ways of managing scarce resources.

Mobility, a long-time key strategy in Maasai pastoralism, has been used to access distant pasture and water, sometimes across international borders. In response to climate change, some Maasai have expanded this strategy to move to new places and to remain mobile in other ways, for example by letting young people take jobs in the city.

Mobility is no longer just about herds and herders; it now involves family members leaving the comforts of home to travel to urban centres (many times quite distant or even across borders) in search of wage labour.

Income from such work can come in handy especially during droughts and scarcity when remitted to families to pay school fees, meet medical costs, and buy food or even water. In periods of abundance, mobility can be a key source of money for restocking, herd growth and home improvement.

Though work-related mobility is not a new phenomenon among the Maasai, it is certainly on the rise, probably an indicator that more households are getting more stressed by climate-induced factors. It may also mean that herding alone may no longer sustain increasing households and hence a complementary income becomes critical.

Additionally, many Maasai are trying to diversify their finances so that there are different income streams to pool in times of a crisis. For example, through education, wage labour, small businesses, and the sale of new agricultural products in connection with traditional livestock and crops are opening up as extra income streams.

This provides more revenue opportunities, and when one income fails, another can be depended upon. Diversification therefore reduces vulnerability, increases resilience in the face of unpredictability.

Arguably, supporting diversification could wean the Maasai from relief and put them on the path to a stronger pastoralist economy and sustainable development.

Finally, the Maasai are developing new ways of organising how they manage scarce natural resources. Changing land tenure has led some to invent new or reinvent versions of traditional principles, such as joint agreements on the management of grass and water according to certain rules, thereby making it easier to get by with fewer resources. For example, households may merge herds and share herding labour to reduce costs and free resources.

Some have also made new agreements about when to move their livestock to certain pastures and wetlands within or beyond group ranches.

Others have abandoned the past collective principles to embrace more individualised property rights, which they believe strengthens their ability to cope. The latter has probably been motivated by changes in land tenure from communal to individual ownership across most of the Kajiado Maasai.

For example, many Maasai households now grow grass on individually owned or leased lands and make silage for their herds, which is a form of ranching. Some increasingly prefer to keep their livestock in paddocks most of the time, and use their land for individual farming purposes, which is a radical change in the way Maasai manage their land.

The big city of Nairobi neighbouring Maasai lands has also caused changes in mindsets as more people now see a better future not just in the vast lands and herds but also in greater interaction with the urban economy to overcome crises.

The strategies of the Maasai illustrate a major point, namely that resilience is not just a question of surviving a crisis and then returning to normal, but about using the experience from each crisis to develop and change resource utilisation, economics and organisation. It is about using experience to continuously innovate for a changing environment and increasingly more complex situations.

The Maasai situation also shows how important it is to bring peoples own experience-based knowledge about what works here into the game of living with unpredictability. Though the Maasai strategies make good practical sense, they are often met with skepticism among many scientists, planners and policy makers who do not always fully understand tacit approaches to resource planning and crisis management.

Yet studies show that expert-based solutions are not necessarily successful when adjusting to unpredictability, scarcity and complexity. Drawing on different forms of knowledge and providing for a democratic dialogue that allows tapping into dynamics of tacit knowledge may lead to better solutions for the Maasai as they adapt to the new reality.

Finally, lessons from current multiple crises illustrate the need for integrated thinking, across not just crises but also scales. The coronavirus crisis has made it difficult to fight the locust plague, and has also hit some of the strategies otherwise used by the Maasai to adapt to climate change.

While climate, locusts and coronavirus may seem like a rare combination, they have not only hit the national economy but also specific communities such as the Maasai even harder. Movement restrictions threaten Maasai social systems and livelihood strategies, which are founded on mobility, among other things. Thus, crises in climate, environment and health can all play together.

Challenges cannot be resolved separately as science, policy and practice attempt a better understanding of such complex situations.

See more here:

Maasai lessons to the world on managing multiple crises - Daily Monitor