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USGS2009

Unconventional energy resources: 2007-2008 review

This paper summarizes five 2007–2008 resource commodity committee reports prepared by the Energy Minerals Division (EMD) of the American Association of Petroleum Geologists. Current United States and global research and development activities related to gas hydrates, gas shales, geothermal resources, oil sands, and uranium resources are included in this review. These commodity reports were written to advise EMD leadership and membership of the current status of research and development of unconventional energy resources. Unconventional energy resources are defined as those resources other than conventional oil and natural gas that typically occur in sandstone and carbonate rocks. Gas hydrate resources are potentially enormous; however, production technologies are still under development. Gas shale, geothermal, oil sand, and uranium resources are now increasing targets of exploration and development, and are rapidly becoming important energy resources that will continue to be developed in the future.

Natural Resources Research↗

USGS2005

High priority needs for range-wide monitoring of North American landbirds

This document is an extension of work done for the Partners in Flight North American Landbird Conservation Plan (Rich et al. 2004). The Continental Plan reviewed conservation status of the 448 native landbird species that regularly breed in the United States and Canada. Two groups of species were identified as having high conservation importance: the PIF Watch List, made up of species for which there is conservation concern, and Stewardship Spices that are particularly characteristic of regional avifaunas. In addition, continental scale monitoring needs were identified for all species. Here we extend the monitoring needs aspect of the Plan, providing additional detail and suggesting the best means of filling the gaps in broad-scale, long-term trend monitoring. This analysis and report was compiled by the Partners in Flight (PIF) Science Committee as a contribution to current work by the North American Bird Conservation Initiative to assess the status of bird population monitoring in North America and to make recommendations for improvements.

Partners in Flight Technical Series↗

USGS2018

Executive summary. In Second State of the Carbon Cycle Report (SOCCR2): A Sustained Assessment Report

Central to life on Earth, carbon is essential to the molecular makeup of all living things and plays a key role in regulating global climate. To understand carbon’s role in these processes, researchers measure and evaluate carbon stocks and fluxes. A stock is the quantity of carbon contained in a pool or reservoir in the Earth system (e.g., carbon in forest trees), and a flux is the direction and rate of carbon’s transfer between pools (e.g., the movement of carbon from the atmosphere into forest trees during photosynthesis). This document, the Second State of the Carbon Cycle Report (SOCCR2), examines the patterns of carbon stocks and fluxes—collectively called the “carbon cycle.” Emphasis is given to these patterns in specific sectors (e.g., agriculture and energy) and ecosystems (e.g., forests and coastal waters) and to the response of the carbon cycle to human activity. The purpose of SOCCR2 is to assess the current state of the North American carbon cycle and to present recent advances in understanding the factors that influence it. Concentrating on North America—Canada, the United States, and Mexico—the report describes carbon cycling for air, land, inland waters (streams, rivers, lakes, and reservoirs), and coastal waters (see Figure ES.1, p. 23). The questions framing the publication A U.S. Carbon Cycle Science Plan (Michalak et al., 2011) inspired development of three slightly modified questions that guide SOCCR2’s content and focus on North America in a global context: How have natural processes and human actions affected the global carbon cycle on land, in the atmosphere, in the ocean and other aquatic systems, and at ecosystem interfaces (e.g., coastal, wetland, and urban-rural)? How have socioeconomic trends affected atmospheric levels of the primary carbon-containing gases, carbon dioxide (CO2) and methane (CH4)? How have species, ecosystems, natural resources, and human systems been impacted by increasing greenhouse gas (GHG) concentrations, associated changes in climate, and carbon management decisions and practices? SOCCR2 synthesizes the most recent understanding of carbon cycling in North America, assessing new carbon cycle findings and information, the state of knowledge regarding core methods used to study the carbon cycle, and future research needed to best inform carbon management and policy options. Focusing on scientific developments in the decade since the First State of the Carbon Cycle Report (SOCCR1; CCSP 2007), SOCCR2 summarizes the past, current, and projected state of carbon sources, sinks, and natural processes, as well as contributions by human activities. In addition to CO2 and CH4, the report sometimes discusses nitrous oxide (N2O), a GHG associated with activities and processes that affect fluxes of carbon gases.1 SOCCR2 also describes improvements in analysis tools; developments in decision support; and new insights into ecosystem carbon cycling, human causes of changes in the carbon cycle, and social science perspectives on carbon. Since publication of SOCCR1, coordinated research from agencies in the three North American countries has enabled innovative observational, analytical, and modeling capabilities to further advance understanding of the North American carbon cycle (see Appendix D: Carbon Measurement Approaches and Accounting Frameworks, p. 834). Some of the report’s main conclusions, based on the Key Findings of each chapter, are highlighted in Box ES.1, Main Findings of SOCCR2, p. 24.

Report↗

USGS1998

Assessment of peak discharge uncertainty in the American River basin, California

Flood-discharge data, current-meter and indirect measurements, and stage-discharge relations, the oldest of which dates to the early 1900's, were used to estimate the uncertainty about annual flood peaks in or near the American River Basin at 20 stream-gaging stations operated by the U.S. Geological Survey. The study estimates that, in the study area, most flood peaks that were determined from current-meter measurements have an uncertainty of about plus or minus 3 percent, whereas the peaks that were determined from indirect measurements have an uncertainty ranging from plus or minus 10 to plus or minus 70 percent. The study also determined that the stage-discharge relations that have been developed for most of the sites in the American River Basin are correct.

Open-File Report↗

USGS2020

Loss of coastal islands along Florida’s Big Bend region: Implications for breeding American oystercatchers

Many coastal-dependent species have undergone large-scale population declines due to impacts from habitat loss, including American oystercatchers ( Haematopus palliatus ). Islands along the Big Bend region of Florida’s Gulf Coast provide important nesting habitat for oystercatchers, but reproductive success here is low and habitat degradation and loss are a major concern. To determine rates and characteristics of habitat loss, we quantified changes in island sizes within two major breeding areas of the Big Bend: the Barge Canal spoil islands and natural islands at Cedar Key. We digitized aerial photographs from the past ~ 40 years, measured area and shoreline retreat of nesting islands, and identified trends over time by fitting linear mixed effects models. The total area of the ten Barge Canal spoil islands decreased by 55% between 1979 and 2016. At Cedar Key, the total area of the six islands measured decreased by 39% between 1974 and 2016, 85% of which occurred after 1995, indicating an increase in erosion rates correlated with oyster reef declines. Changes in available nesting habitat varied between the Barge Canal and Cedar Key islands due to differences in physical attributes; however, all islands significantly decreased in size over time. Given the long life and high site fidelity of American oystercatchers, these islands may currently be acting as an ecological trap for this species. Climate change, sea-level rise, and loss of oyster reefs are likely to continue to drive oystercatcher habitat loss throughout their range; thus, creation and restoration of oyster reefs and nesting islands will become increasingly important.

Florida↗

USGS2026

Constructed value of information with iterative scoring and parametric uncertainty to identify management-relevant research priorities for a declining raptor species

Constructed value of information (CVoI) is an expert elicitation decision-analytic tool used to prioritize sources of uncertainty based on their potential to improve decision outcomes if resolved. Despite increased application of CVoI, the robustness of CVoI prioritization of sources of uncertainty relative to differences in expert elicitation and scoring methods has not been evaluated. We engaged a group of species experts in a decision-analytic process to elicit uncertainties, framed as alternative hypotheses, about current population declines of the American kestrel ( Falco sparverius ) in the United States. Participants scored 13 hypotheses across 3 CVoI criteria, which are defined as constructed scales. Rather than experts selecting a single score per criterion, we used a likelihood point method to incorporate parametric uncertainty in the scoring process, in which experts were given 100 points to distribute across possible score categories within the criterion-specific constructed scale. Experts provided scores over 2 scoring rounds, with an opportunity to review and discuss initial scores between rounds. We used a Shannon entropy calculation to quantify how evenly participants allotted their points. We used simulation to evaluate the robustness of our prioritization results relative to a scoring method in which participants selected a single score category for each criterion. Participants often spread their points across 2 adjacent scores, reflecting parametric uncertainty. For one third of the hypothesis-scoring round combinations, the prioritization results differed in approximately 50% of simulations. The highest scoring hypotheses related to how the use of artificial versus natural nest cavities affects fecundity or survival, whether winter roosting sites are a limiting factor for population growth, and whether gamebird habitat management may benefit kestrel populations. Our CVoI prioritization framework can be used to develop collaborative research that is directly relevant to a management decision and is an advance in eliciting more representative expert beliefs.

Conservation Biology↗

USGS2017

From salmon to shad: Shifting sources of marine-derived nutrients in the Columbia River Basin

Like Pacific salmon ( Oncorhynchus spp.), nonnative American shad ( Alosa sapidissima ) have the potential to convey large quantities of nutrients between the Pacific Ocean and freshwater spawning areas in the Columbia River Basin (CRB). American shad are now the most numerous anadromous fish in the CRB, yet the magnitude of the resulting nutrient flux owing to the shift from salmon to shad is unknown. Nutrient flux models revealed that American shad conveyed over 15,000 kg of nitrogen (N) and 3,000 kg of phosphorus (P) annually to John Day Reservoir, the largest mainstem reservoir in the lower Columbia River. Shad were net importers of N, with juveniles and postspawners exporting just 31% of the N imported by adults. Shad were usually net importers of P, with juveniles and postspawners exporting 46% of the P imported by adults on average. American shad contributed <0.2% of the total annual P load into John Day Reservoir, but during June when most adult shad are migrating into John Day Reservoir, they contributed as much as 2.0% of the P load. Nutrient inputs by American shad were similar to current but far less than historical inputs of Pacific salmon owing to their smaller size. Given the relatively high background P levels and low retention times in lower Columbia River reservoirs, it is unlikely that shad marine-derived nutrients affect nutrient balances or food web productivity through autotrophic pathways. However, a better understanding of shad spawning aggregations in the CRB is needed.

Columbia River, John Day Reservoir↗

USGS2008

Diets of Lesser Scaup during spring migration throughout the upper-Midwest are consistent with the spring condition hypothesis

The spring condition hypothesis (SCH) states that the current decline of the North American scaup population (Lesser [Aythya affinis] and Greater Scaup [A. marila] combined) is due to a decline in quality or availability of scaup foods on wintering, spring migration, or breeding areas that has caused a reduction in female body condition and subsequent reproductive success. Our previous research indicated that forage quality in diets of Lesser Scaup (hereafter scaup) at two sites in Northwestern Minnesota was lower in springs 2000-2001 than that reported for springs 1986-1988, consistent with the SCH. Accordingly, we further tested the SCH at a landscape scale, by comparing amounts of amphipods in diets (index of forage quality) of scaup (N = 263) collected in springs 2003-2005 from seven eco-physiographic regions in Iowa, Minnesota, and North Dakota in relation to data from Northwestern Minnesota during springs 2000-2001. We found that aggregate percentages of Gammarus lacustris and Hyalella azteca (amphipods) in scaup diets during springs 2000-2001 in Northwest Minnesota were similar to those in the Iowa Prairie Pothole, Minnesota Morainal, Minnesota Glaciated Plains, Red River Valley, and Northwestern Minnesota in springs 2003-2005; however, scaup consumed relatively higher aggregate percentages of Gammarus lacustris and Hyalella azteca in North Dakota Missouri Coteau and North Dakota Glaciated Plains. Females in Iowa were over three times less likely to have consumed food than those in North Dakota, despite previous research indicating similar foraging rates among these regions. Mean mass of scaup diet samples throughout the upper-Midwest were 77 mg (49%) and 87 mg (52%) lower than those of historical studies in Minnesota and Manitoba, respectively. We conclude that there has been a decrease in forage quality for scaup in Iowa and Minnesota and a decrease in the amount of forage consumed throughout the upper-Midwest, consistent with the SCH.

Minnesota↗

USGS2015

Who invented the mule deer ( Odocoileus hemionus )? On the authorship of the fraudulent 1812 journal of Charles Le Raye

The captivity journal of Charles Le Raye was first published in 1812 as a chapter in A topographical description of the state of Ohio, Indiana Territory, and Louisiana , a volume authored anonymously by a late officer in the U. S. Army. Le Raye was purported to be a French Canadian fur trader who, as a captive of the Sioux, had travelled across broad portions of the Missouri and Yellowstone river drainages a few years before the Lewis and Clark expedition (1804-1806), and his account of the land, its people, and its natural resources was relied upon as a primary source by generations of natural historians, geographers, and ethnographers. Based directly on descriptions of animals in the published journal, the naturalist Constantine S. Rafinesque named seven new species of North American mammals, including what are currently recognized as the mule deer ( Odocoileus hemionus ) and a Great Plains subspecies of white-tailed deer ( O. virginianus macrourus ). Unfortunately, Le Raye never existed, and historical, geographical, and ethnographical evidence indicates that the journal is fraudulent. Determining the author of this work is relevant to identifying the sources used to construct it, which may help us to understand the real animals upon which Rafinesque's species are based. Traditionally, authorship of the volume was attributed to Jervis Cutler, but his role in composing the fraudulent Le Raye journal has been called into question. In this paper, I present additional evidence supporting the hypothesis that Jervis Cutler bears primary responsibility for the Le Raye journal and that he had the background, opportunity, and potential motive to author it.

Archives of Natural History↗

USGS1987

In search of the Abrams post office, Trinity County

An understanding of earth history depends in part on stratigraphy, a division of geology in which the distinctive features of natural units or formations of layered rocks are studied and described and names are assigned to them. The procedures for describing and naming rock units in a uniform way are incorporated in documents known as stratigraphic codes. The North American Stratigraphic Code (1983) is currently used by most geologists in the United States when formation names are selected. Rock unit names consist of a geographic name, generally taken from a natural feature near the locality where the unit was first described, followed by a descriptive feature, usually the dominant rock type in the unit. Although the procedure for naming a rock unit seems straightforward, stratigraphic nomenclature can lead to confusion when the principles outlined in the stratigraphic code are ignored or incorrectly applied. This paper traces the naming of the Abrams Mica Schist, one of the major units of the northern California Klamath Mountains. It describes how uncertainty about the location of the geographic feature after which the unit was named has led to conflicting terminology. The search revealed some interesting history of the early days of mining in the Coffee Creek region of the Trinity Alps in Trinity County.

California Geology↗

USGS2019

Upper thermal tolerance and heat shock protein response of juvenile American shad (Alosa sapidissima)

Juvenile American shad ( Alosa sapidissima ) experience a wide range of temperatures in rivers before migrating to the ocean. Temperatures in these freshwater environments can vary greatly spatially, seasonally, year-to-year, and can be impacted by anthropogenic factors such as power plant discharge or climate change. Currently, there is uncertainty concerning juvenile American shad thermal tolerance due to a lack of a well-controlled study. Here, we report results of laboratory experiments to establish the upper thermal tolerance and heat shock protein response of juvenile American shad exposed to gradually increasing temperatures. Upper thermal tolerance was determined to be 35 °C (median; range = 34–36 °C) when fish were acclimated to 25 °C and temperatures were raised 1 °C day −1 . Heat shock protein response was indicated by changes in branchial mRNA abundance of the inducible heat shock protein 90 alpha ( hsp90α ), which was significantly elevated (more than 5-fold increase) at 30 °C, and highest in fish that had reached their upper thermal maximum between 34 and 36 °C. Our findings indicate a higher upper thermal tolerance than previously reported for juvenile American shad, and an onset temperature of hsp90α induction at 30 °C, a temperature juvenile American shad commonly experience during summer months.

Estuaries and Coasts↗

USGS2020

The role of sand lances (Ammodytes sp.) in the Northwest Atlantic Ecosystem: A synthesis of current knowledge with implications for conservation and management

The American sand lance ( Ammodytes americanus , Ammodytidae) and the Northern sand lance ( A. dubius , Ammodytidae) are small forage fishes that play an important functional role in the Northwest Atlantic Ocean (NWA). The NWA is a highly dynamic ecosystem currently facing increased risks from climate change, fishing and energy development. We need a better understanding of the biology, population dynamics and ecosystem role of Ammodytes to inform relevant management, climate adaptation and conservation efforts. To meet this need, we synthesized available data on the (a) life history, behaviour and distribution; (b) trophic ecology; (c) threats and vulnerabilities; and (d) ecosystem services role of Ammodytes in the NWA. Overall, 72 regional predators including 45 species of fishes, two squids, 16 seabirds and nine marine mammals were found to consume Ammodytes . Priority research needs identified during this effort include basic information on the patterns and drivers in abundance and distribution of Ammodytes , improved assessments of reproductive biology schedules and investigations of regional sensitivity and resilience to climate change, fishing and habitat disturbance. Food web studies are also needed to evaluate trophic linkages and to assess the consequences of inconsistent zooplankton prey and predator fields on energy flow within the NWA ecosystem. Synthesis results represent the first comprehensive assessment of Ammodytes in the NWA and are intended to inform new research and support regional ecosystem‐based management approaches.

Northwest Atlantic↗

USGS2014

Circulating fat-soluble vitamin concentrations and nutrient composition of aquatic prey eaten by American oystercatchers ( Haematopus palliatus ) in the southeastern United States

The American oystercatcher ( Haematopus palliatus palliatus ) is currently listed as a species of high concern by the United States Shorebird Conservation Plan. Because nutritional status directly impacts overall health and reproduction of individuals and populations, adequate management of a wildlife population requires intimate knowledge of a species' diet and nutrient requirements. Fat-soluble vitamin concentrations in blood plasma obtained from American oystercatchers and proximate, vitamin, and mineral composition of various oystercatcher prey species were determined as baseline data to assess nutritional status and nutrient supply. Bird and prey species samples were collected from the Cape Romain region, South Carolina, USA, and the Altamaha River delta islands, Georgia, USA, where breeding populations appear relatively stable in recent years. Vitamin A levels in blood samples were higher than ranges reported as normal for domestic avian species, and vitamin D concentrations were lower than anticipated based on values observed in poultry. Vitamin E levels were within ranges previously reported for avian groups with broadly similar feeding niches such as herons, gulls, and terns (eg, aquatic/estuarine/marine). Prey species (oysters, mussels, clams, blood arks [ Anadara ovalis ], whelks [ Busycon carica ], false angel wings [ Petricola pholadiformis ]) were similar in water content to vertebrate prey, moderate to high in protein, and moderate to low in crude fat. Ash and macronutrient concentrations in prey species were high compared with requirements of carnivores or avian species. Prey items analyzed appear to meet nutritional requirements for oystercatchers, as estimated by extrapolation from domestic carnivores and poultry species; excesses, imbalances, and toxicities—particularly of minerals and fat-soluble vitamins—may warrant further investigation.

Georgia, South Carolina↗

USGS2022

Comparative assessment of laboratory-derived thermal maxima of Gila trout (oncorhynchus Gilae) with current stream temperatures

Gila trout ( Oncorhynchus gilae ) represent an iconic species of the American Southwest. The salmonid has survived extensive logging, livestock grazing, and mining, and is currently threatened by climate change, wildfire, and extended drought. Long-term conservation and recovery of the species and its unique lineages rely on stocking and translocation into historically inhabited streams. Thus, the fish's thermal tolerance is essential in determining suitable habitat and potential vulnerability to a warming climate. We compared a laboratory-derived temperature metric, critical thermal maximum (CTMax), in hatchery-reared Gila trout from three lineages (Main Diamond, South Diamond, and Whiskey Creek) to determine if CTMax differed among the lineages. The average initial (28.9°C, SD = 0.81°C) and final (29.2°C, SD = 0.74°C) temperature at loss of righting responses did not differ across the lineages. We compared the CTMax values with stream temperatures across three drainages representative of extant Gila trout populations from spring 2015 to fall 2018. The East Fork Gila River drainage was represented by more extreme stream temperatures. The maximum daily maximum temperature (i.e., single highest temperature) varied from 24.1 to 33.4°C, exceeding CTMax in four of the five streams. The maximum daily temperature varied from 12.1 to 28.6°C, and the mean weekly maximum temperature varied from 19.9 to 31.1°C. Mean weekly maximum temperature in Lower Diamond Creek exceeded CTMax on 11 occasions. Stream temperatures were cooler within the Middle and the West Fork Gila River drainages and did not exceed CTMax. Intermittency loggers within the East Fork Gila River drainage, which supports Main Diamond and South Diamond lineages of Gila trout, recorded over 300 days of intermittency during a drought. Continued long-term monitoring of stream temperature and comparison with CTMax of Gila trout could assist with decisions of which streams in the Gila Drainage are suitable for Gila trout recovery, stocking, and translocation.

New Mexico↗

USGS2020

Case Study 4: NABat acoustic monitoring allows inferences about bat populations at multiple scales

North American bats face unprecedented risks from continuing and emerging threats including white-nose syndrome, wind energy development, and habitat loss. Many species of bats are thought to be recently experiencing unparalleled population declines unlike any previously observed (O’Shea et al. 2016). The North American Bat Monitoring Program (NABat) was conceived to better understand the true ecological consequences of these large-scale population reductions (Loeb et al. 2015). NABat aims is to improve the state of conservation science for the 47 species of bats shared by Canada, United States, and Mexico. To meet this objective, NABat offers standardize protocols and a unifying sample design facilitating a multi-agency, multinational, collaborative monitoring effort. A key element of NABat is cross-boundary partner coordination and sharing of limited resources for the collection of bat echolocation data. Here we provide three compelling examples of how NABat provides a convenient framework for using acoustic data to assess the potential impacts of current and future threats to North American bats across multiple spatial scales.

Oregon↗

USGS2006

Population trajectory of burrowing owls (Athene cunicularia) in eastern Washington

Anecdotal evidence suggests that burrowing owls have declined in Washington. The Washington Department of Fish and Wildlife is currently conducting a status review for burrowing owls which will help determine whether they should be listed as threatened or endangered in the state. To provide insights into the current status of burrowing owls (Athene cunicularia), we analyzed data from the North American Breeding Bird Survey using two analytical approaches to determine their current population trajectory in eastern Washington. We used a one-sample t-test to examine whether trend estimates across all BBS routes in Washington differed from zero. We also used a mixed model analysis to estimate the rate of decline in number of burrowing owls detected between 1968 and 2005. The slope in number of burrowing owls detected was negative for 12 of the 16 BBS routes in Washington that have detected burrowing owls. Numbers of breeding burrowing owls detected in eastern Washington declined at a rate of 1.5% annually. We suggest that all BBS routes that have detected burrowing owls in past years in eastern Washington be surveyed annually and additional surveys conducted to track population trends of burrowing owls at finer spatial scales in eastern Washington. In the meantime, land management and regulatory agencies should ensure that publicly managed areas with breeding burrowing owls are not degraded and should implement education and outreach programs to promote protection of privately owned areas with breeding owls.

Northwest Science↗

USGS2006

Change in atmospheric mineral aerosols in response to climate: Last glacial period, preindustrial, modern, and doubled carbon dioxide climates

Desert dust simulations generated by the National Center for Atmospheric Research's Community Climate System Model for the current climate are shown to be consistent with present day satellite and deposition data. The response of the dust cycle to last glacial maximum, preindustrial, modern, and doubled-carbon dioxide climates is analyzed. Only natural (non-land use related) dust sources are included in this simulation. Similar to some previous studies, dust production mainly responds to changes in the source areas from vegetation changes, not from winds or soil moisture changes alone. This model simulates a +92%, +33%, and -60% change in dust loading for the last glacial maximum, preindustrial, and doubled-carbon dioxide climate, respectively, when impacts of carbon dioxide fertilization on vegetation are included in the model. Terrestrial sediment records from the last glacial maximum compiled here indicate a large underestimate of deposition in continental regions, probably due to the lack of simulation of glaciogenic dust sources. In order to include the glaciogenic dust sources as a first approximation, we designate the location of these sources, and infer the size of the sources using an inversion method that best matches the available data. The inclusion of these inferred glaciogenic dust sources increases our dust flux in the last glacial maximum from 2.1 to 3.3 times current deposition. Copyright 2006 by the American Geophysical Union.

Journal of Geophysical Research D: Atmospheres↗

USGS2017

Centennial-scale reductions in nitrogen availability in temperate forests of the United States

Forests cover 30% of the terrestrial Earth surface and are a major component of the global carbon (C) cycle. Humans have doubled the amount of global reactive nitrogen (N), increasing deposition of N onto forests worldwide. However, other global changes—especially climate change and elevated atmospheric carbon dioxide concentrations—are increasing demand for N, the element limiting primary productivity in temperate forests, which could be reducing N availability. To determine the long-term, integrated effects of global changes on forest N cycling, we measured stable N isotopes in wood, a proxy for N supply relative to demand, on large spatial and temporal scales across the continental U.S.A. Here, we show that forest N availability has generally declined across much of the U.S. since at least 1850 C.E. with cool, wet forests demonstrating the greatest declines. Across sites, recent trajectories of N availability were independent of recent atmospheric N deposition rates, implying a minor role for modern N deposition on the trajectory of N status of North American forests. Our results demonstrate that current trends of global changes are likely to be consistent with forest oligotrophication into the foreseeable future, further constraining forest C fixation and potentially storage.

Scientific Reports↗