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At least 235 records · Page 13Linked to original sources

Mapping Typha Domingensis in the Cienega de Santa Clara Using Satellite Images, Global Positioning System, and Spectrometry

The Cienega de Santa Clara, Sonora, Mexico, a brackish wetland area created near the delta of the Colorado River from drainage effluent flowing from the United States since 1977, may undergo changes owing to the operation of the Yuma Desalting Plant in the United States. This has become the largest wetland in the delta region containing rare and endangered species, yet little is known about the environmental impact of these changes. The water quality of the marsh is of growing concern to the Bureau of Reclamation (BOR) which operates the Desalting Plant. Consequently, the BOR solicited the U.S. Geological Survey to investigate the limits and usefulness of satellite, global positioning system (GPS), and spectra data to map the Typha domingensis (cattail) of the Cienega de Santa Clara. Typha domingensis was selected by the BOR as the Cienega de Santa Clara indicator species to best predict the environmental effects of effl uent from the Yuma Desalting Plant. The successful base mapping of Typha domingensis will provide a viable tool for long-term monitoring and stress detection in the Cienega de Santa Clara.

Open-File Report

Sensitivity of the projected hydroclimatic environment of the Delaware River basin to formulation of potential evapotranspiration

The Delaware River Basin (DRB) encompasses approximately 0.4 % of the area of the United States (U.S.), but supplies water to 5 % of the population. We studied three forested tributaries to quantify the potential climate-driven change in hydrologic budget for two 25-year time periods centered on 2030 and 2060, focusing on sensitivity to the method of estimating potential evapotranspiration (PET) change. Hydrology was simulated using the Water Availability Tool for Environmental Resources (Williamson et al. 2015 ). Climate-change scenarios for four Coupled Model Intercomparison Project Phase 5 (CMIP5) global climate models (GCMs) and two Representative Concentration Pathways (RCPs) were used to derive monthly change factors for temperature (T), precipitation (PPT), and PET according to the energy-based method of Priestley and Taylor ( 1972 ). Hydrologic simulations indicate a general increase in annual (especially winter) streamflow (Q) as early as 2030 across the DRB, with a larger increase by 2060. This increase in Q is the result of (1) higher winter PPT, which outweighs an annual actual evapotranspiration (AET) increase and (2) (for winter) a major shift away from storage of PPT as snow pack. However, when PET change is evaluated instead using the simpler T-based method of Hamon ( 1963 ), the increases in Q are small or even negative. In fact, the change of Q depends as much on PET method as on time period or RCP. This large sensitivity and associated uncertainty underscore the importance of exercising caution in the selection of a PET method for use in climate-change analyses.

Climatic Change

Coastal Tree-Ring Records for Paleoclimate and Paleoenvironmental Applications in North America

For more than a century, tree-ring research has identified relationships between climatic and ecological conditions and tree growth to describe past environments and constrain future ecosystem vulnerabilities. Tree-ring records are frequently used as environmental proxies that extend knowledge of past climate and ecology on millennial scales. Many of the most pressing global change questions facing North America concern the rate of climate change and vulnerability of ecosystems and society along the coast. The opportunities and applications in dendrochronology continue to grow with advancing methodologies, faster computational ability, and the cost-reduction of many chemical and anatomical analyses. Here, we propose that many pressing global change questions that affect coastal communities can be addressed using dendrochronological techniques. We review coastal tree-ring studies that demonstrate the utility and potential for future tree-ring studies in the northeastern, southeastern, northwestern, and southwestern North American coasts. Additionally, we show that tree-ring chronologies along the coast give insight into local and regional climate phenomena that are distinct from nearby, inland tree-ring chronologies of the same species. Lastly, we identify opportunities for coastal dendrochronology and encourage the collection of more tree-ring records that are directly impacted by coastal phenomena.

Quaternary Science Reviews

It's time for bold new approaches to link delta science and policymaking

California’s Sacramento–San Joaquin Delta is widely recognized as a highly damaged ecosystem. The Delta is also emblematic of a growing sense worldwide that society needs to do a better job of using scientific knowledge to guide conservation and resource management policies. Fortunately, we now have an unprecedented opportunity to get it right in building structures that support effective science–policy linkages in the Delta. By adopting bold steps to implement a “one Delta, one science” approach for a new Delta Science Plan, California can become a leading example of how to tackle the global problem of rapid ecological change and biodiversity loss. In this essay, we first describe the current paradox—continued environmental declines despite considerable investments in science and policy actions—and the high stakes of gambling with failure. Next, we explore why it is so hard to use scientific knowledge to design and implement policies that meet society’s sustainability goals. We then outline promising ways to overcome these obstacles, drawing on recent experiences. We conclude with thoughts on how to leverage this experience to develop a bold new approach to Delta science.

California

Resource inventory of marine and estuarine fishes of the West Coast and Alaska: A checklist of North Pacific and Arctic Ocean species from Baja California to the Alaska - Yukon border

This is a comprehensive inventory of the fish species recorded in marine and estuarine waters between the Alaska–Yukon Territory border in the Beaufort Sea and Cabo San Lucas at the southern end of Baja California and out about 300 miles from shore. Our westernmost range includes the eastern Bering Sea and Aleutian Islands. In addition, we have also included our best impressions of the species that might reasonably be expected to be members of the West Coast ichthyofauna but have not yet been captured or reported within our study area. These species are marked with an asterisk (*) and have been reported (1) in the western Bering Sea; (2) off Canada’s Yukon Territory and adjacent portions of the Northwest Territories; (3) along the southern-eastern tip (non-Pacific side) of Baja California; and (4) in waters somewhat beyond 300 miles from shore. Although the term West Coast usually refers to the coast of the continuous western states, our usage herein means the entire study area. The West Coast inventory within this range encompasses fish fauna from 44 orders, 232 families, and a minimum of 1,450 species. Please note that introduced and invasive fish species are marked by double asterisks (**) and that their scientific names are highlighted in gray. We have compiled this document because the most geographically inclusive previous inventories (Jordan and Evermann 1896a, Jordan et al. 1930) are largely of historical interest and are out of date. More recent lists and compilations have either focused on relatively narrow taxonomic groups (e. g., Kramer et al. 1995, Love et al. 2002), are regional in scope (e. g., Hart 1973, Hubbs et al. 1979, Mecklenburg et al. 2002), or focus on commonly observed species (e. g., Miller and Lea 1972, Eschmeyer and Herald 1983). With the explosion of coastal research and environmental assessments, beginning in the 1970s, and more recently, renewed scientific interest in biodiversity (e.g., effects of global climate change), our own studies on related subjects regarding fish populations, assemblages, and biological habitats, suggested this was the appropriate time to update and summarize our knowledge.

Report

Integrated monitoring of ecological conditions in wetland-upland landscapes

Landscapes of interwoven wetlands and uplands offer a rich set of ecosystem goods and services. Managing lands to maximize ecosystem services requires information that distinguishes change caused by local actions from broader-scale shifts in climate, land use, and other forms of global change. Satellite and airborne sensors collect valuable data for this purpose, especially when the data are analyzed along with data collected from ground-based sensors. The U.S. Geological Survey (USGS) is using remote sensing technology in this way as part of the Terrestrial Wetland Global Change Research Network to assess effects of climate change interacting with land-use change and other potential stressors along environmental gradients of wetland-upland landscapes in the United States and Canada.

Fact Sheet

Geologic Map of MTM 35337, 40337, and 45337 Quadrangles, Deuteronilus Mensae Region of Mars

Deuteronilus Mensae, first defined as an albedo feature at lat 35.0 deg N., long 5.0 deg E., by U.S. Geological Survey (USGS) and International Astronomical Union (IAU) nomenclature, is a gradational zone along the dichotomy boundary in the northern mid-latitudes of Mars. The boundary in this location includes the transition from the rugged cratered highlands of Arabia Terra to the northern lowland plains of Acidalia Planitia. Within Deuteronilus Mensae, polygonal mesas are prominent along with features diagnostic of Martian fretted terrain, including lobate debris aprons, lineated valley fill, and concentric crater fill. Lobate debris aprons, as well as the valley and crater fill deposits, are geomorphic indicators of ground ice, and their concentration in Deuteronilus Mensae is of great interest because of their potential association with Martian climate change. The paucity of impact craters on the surfaces of debris aprons and the presence of ice-cemented mantle material imply young (for example, Amazonian) surface ages that are consistent with recent climate change in this region of Mars. North of Deuteronilus Mensae are the northern lowlands, a potential depositional sink that may have had large standing bodies of water or an ocean in the past. The northern lowlands have elevations that are several kilometers below the ancient cratered highlands with significantly younger surface ages. The morphologic and topographic characteristics of the Deuteronilus Mensae region record a diverse geologic history, including significant modification of the ancient highland plateau and resurfacing of low-lying regions. Previous studies of this region have interpreted a complex array of geologic processes, including eolian, fluvial and glacial activity, coastal erosion, marine deposition, mass wasting, tectonic faulting, effusive volcanism, and hydrovolcanism. The origin and age of the Martian crustal dichotomy boundary are fundamental questions that remain unresolved at the present time. Several scenarios for its formation, including single and multiple large impact events, have been proposed and debated in the literature. Endogenic processes whereby crust is thinned by internal mantle convection and tectonic processes have also been proposed. Planetary accretion models and isotopic data from Martian meteorites suggest that the crust formed very early in Martian history. Using populations of quasi-circular depressions extracted from the topography of Mars, other studies suggest that the age difference between the highlands and lowlands could be ~100 m.y.. Furthermore, understanding the origin and age of the dichotomy boundary has been made more complicated due to significant erosion and deposition that have modified the boundary and its adjacent regions. The resulting diversity of terrains and features is likely a combined result of ancient and recent events. Detailed geologic analyses of dichotomy boundary zones are important for understanding the spatial and temporal variations in highland evolution. This information, and comparisons to other highland regions, can help elucidate the scale of potential environmental changes. Previous geomorphic and geologic mapping investigations of the Deuteronilus Mensae region have been completed at local to global scales. The regional geology was first mapped by Lucchitta (1978) at 1:5,000,000 scale using Mariner 9 data. This study concluded that high crater flux early in Martian history formed overlapping craters and basins that were later filled by voluminous lava flows that buried the impacted surface, creating the highlands. After this period of heavy bombardment, fluvial erosion of the highlands formed the canyons and valleys, followed by dissection that created the small mesas and buttes, and later, formation of the steep escarpment marking the present-day northern highland margin. After valley dissection, mass wasting and eolian processes caused lateral retreat of mesas and buttes

Scientific Investigations Map

Emerging viral diseases of fish and shrimp

The rise of aquaculture has been one of the most profound changes in global food production of the past 100 years. Driven by population growth, rising demand for seafood and a levelling of production from capture fisheries, the practice of farming aquatic animals has expanded rapidly to become a major global industry. Aquaculture is now integral to the economies of many countries. It has provided employment and been a major driver of socio-economic development in poor rural and coastal communities, particularly in Asia, and has relieved pressure on the sustainability of the natural harvest from our rivers, lakes and oceans. However, the rapid growth of aquaculture has also been the source of anthropogenic change on a massive scale. Aquatic animals have been displaced from their natural environment, cultured in high density, exposed to environmental stress, provided artificial or unnatural feeds, and a prolific global trade has developed in both live aquatic animals and their products. At the same time, over-exploitation of fisheries and anthropogenic stress on aquatic ecosystems has placed pressure on wild fish populations. Not surprisingly, the consequence has been the emergence and spread of an increasing array of new diseases. This review examines the rise and characteristics of aquaculture, the major viral pathogens of fish and shrimp and their impacts, and the particular characteristics of disease emergence in an aquatic, rather than terrestrial, context. It also considers the potential for future disease emergence in aquatic animals as aquaculture continues to expand and faces the challenges presented by climate change.

Veterinary Research

Data management and interactive visualizations for the evolving marine biodiversity observation network

Assessing the current state of and predicting change in the ocean’s biological and ecosystem resources requires observations and research to safeguard these valuable public assets. The Marine Biodiversity Observation Network (MBON) partnered with the Global Ocean Observing System Biology and Ecosystems Panel and the Ocean Biodiversity Information System to address these needs through collaboration, data standardization, and data sharing. Here, we describe the generalized MBON data processing flow, which includes several steps to ensure that data are findable, accessible, interoperable, and reusable. By following this flow, data collected and managed by MBON have contributed to our understanding of the Global Ocean Observing System Essential Ocean Variables and demonstrated the value of web-based, interactive tools to explore and better understand environmental change. Although the MBON’s generalized data processing flow is already in practice, work remains in building ontologies for biological concepts, improving processing scripts for data standardization, and speeding up the data collection-to-sharing timeframe.

Oceanography

Food and temperature stressors have opposing effects in determining flexible migration decisions in brown trout (Salmo trutta )

With rapid global change, organisms in natural systems are exposed to a multitude of stressors that likely co‐occur, with uncertain impacts. We explored individual and cumulative effects of co‐occurring environmental stressors on the striking, yet poorly understood, phenomenon of facultative migration. We reared offspring of a brown trout population that naturally demonstrates facultative anadromy (sea migration), under different environmental stressor treatments and measured life history responses in terms of migratory tactics and freshwater maturation rates. Juvenile fish were exposed to reduced food availability, temperatures elevated to 1.8°C above natural conditions or both treatments in combination over 18 months of experimental tank rearing. When considered in isolation, reduced food had negative effects on the size, mass and condition of fish across the experiment. We detected variable effects of warm temperatures (negative effects on size and mass, but positive effect on lipids). When combined with food restriction, temperature effects on these traits were less pronounced, implying antagonistic stressor effects on morphological traits. Stressors combined additively, but had opposing effects on life history tactics: migration increased and maturation rates decreased under low food conditions, whereas the opposite occurred in the warm temperature treatment. Not all fish had expressed maturation or migration tactics by the end of the study, and the frequency of these ‘unassigned’ fish was higher in food deprivation treatments, but lower in warm treatments. Fish showing migration tactics were smaller and in poorer condition than fish showing maturation tactics, but were similar in size to unassigned fish. We further detected effects of food restriction on hypo‐osmoregulatory function of migrants that may influence the fitness benefits of the migratory tactic at sea. We also highlight that responses to multiple stressors may vary depending on the response considered. Collectively, our results indicate contrasting effects of environmental stressors on life history trajectories in a facultatively migratory species.

Global Change Biology

Disturbances drive changes in coral community assemblages and coral calcification capacity

Anthropogenic environmental change has increased coral reef disturbance regimes in recent decades, altering the structure and function of many coral reefs globally. In this study, we used coral community survey data collected from 1996 to 2015 to evaluate coral calcification capacity (CCC) dynamics with respect to recorded pulse disturbances for 121 reef sites in the Main Hawaiian Islands and Mo'orea (French Polynesia) in the Pacific and the Florida Keys Reef Tract and St. John (U.S. Virgin Islands) in the Western Atlantic. CCC remained relatively high in the Main Hawaiian Islands in the absence of recorded widespread disturbances; declined and subsequently recovered in Mo'orea following a crown-of-thorns sea star outbreak, coral bleaching, and major cyclone; decreased and remained low following coral bleaching in the Florida Keys Reef Tract; and decreased following coral bleaching and disease in St. John. Coral taxa have diverse calcification rates and susceptibility to disturbances characterized by their life history strategies. As a result, changes in CCC over the time series in this study were driven by a combination of shifts in both overall coral cover and in the contributions of calcification by the dominant calcifying coral taxa to CCC. Analysis of coral life history strategies showed that ‘weedy’ corals increased their contributions to CCC over time while ‘competitive’ corals decreased. Conversely, shifts in contributions by ‘stress-tolerant’ and ‘generalist’ corals to CCC varied by taxa across the regions. The increasing frequency and intensity of disturbances under 21st century global change is therefore predicted to affect CCC for many coral reefs with potentially lower and more variable CCC sustained under increased disturbance regimes by the increasing dominance of ‘weedy’ and some ‘stress-tolerant’ corals.

Ecosphere

Interactions between chemical and climate stressors: A role for mechanistic toxicology in assessing climate change risks

Incorporation of global climate change (GCC) effects into assessments of chemical risk and injury requires integrated examinations of chemical and nonchemical stressors. Environmental variables altered by GCC (temperature, precipitation, salinity, pH) can influence the toxicokinetics of chemical absorption, distribution, metabolism, and excretion as well as toxicodynamic interactions between chemicals and target molecules. In addition, GCC challenges processes critical for coping with the external environment (water balance, thermoregulation, nutrition, and the immune, endocrine, and neurological systems), leaving organisms sensitive to even slight perturbations by chemicals when pushed to the limits of their physiological tolerance range. In simplest terms, GCC can make organisms more sensitive to chemical stressors, while alternatively, exposure to chemicals can make organisms more sensitive to GCC stressors. One challenge is to identify potential interactions between nonchemical and chemical stressors affecting key physiological processes in an organism. We employed adverse outcome pathways, constructs depicting linkages between mechanism-based molecular initiating events and impacts on individuals or populations, to assess how chemical- and climate-specific variables interact to lead to adverse outcomes. Case examples are presented for prospective scenarios, hypothesizing potential chemical–GCC interactions, and retrospective scenarios, proposing mechanisms for demonstrated chemical–climate interactions in natural populations. Understanding GCC interactions along adverse outcome pathways facilitates extrapolation between species or other levels of organization, development of hypotheses and focal areas for further research, and improved inputs for risk and resource injury assessments.

Environmental Toxicology and Chemistry

Forest Vegetation Monitoring Protocol for National Parks in the North Coast and Cascades Network

Plant communities are the foundation for terrestrial trophic webs and animal habitat, and their structure and species composition are an integrated result of biological and physical drivers (Gates, 1993). Additionally, they have a major role in geologic, geomorphologic and soil development processes (Jenny, 1941; Stevens and Walker, 1970). Throughout most of the Pacific Northwest, environmental conditions support coniferous forests as the dominant vegetation type. In the face of anthropogenic climate change, forests have a global role as potential sinks for atmospheric carbon (Goodale and others, 2002). Consequently, knowledge of the status of forests in the three large parks of the NCCN [that is, Mount Rainier (MORA), North Cascades (NOCA), and Olympic (OLYM) National Parks] is fundamental to understanding the condition of Pacific Northwest ecosystems. Diverse climate and soil properties across the Pacific Northwest result in a variety of forest types (Franklin and Dyrness, 1973; Franklin and others, 1988; Henderson and others, 1989, 1992). The mountainous terrain of Mount Rainier, North Cascades, and Olympic National Parks create steep elevational and precipitation gradients within and among the parks: collectively, these parks span from sea level to more than 4,200 m; and include areas with precipitation from 90 to more than 500 cm. The resulting forests range from coastal rainforests with dense understories and massive trees draped with epiphytes; to areas with drought-adapted Ponderosa pines; to high-elevation subalpine fir forests interspersed with meadows just below treeline (table 1). These forests, in turn, are the foundation for other biotic communities constituting Pacific Northwest ecosystems.

Techniques and Methods

Global patterns of tree stem growth and stand aboveground wood production in mangrove forests

Mangrove forests provide important ecological and economic services including carbon sequestration and storage. The conservation and restoration of mangroves are expected to play an important role in mitigating climate change, and understanding the factors influencing mangrove stem growth and wood production are important in predicting and improving mangrove carbon sequestration and responses to environmental change. In this study, we collected data of individual diameter at breast height (DBH) growth rate and stand level aboveground wood production in both non-plantation (commonly termed as natural) mangroves and mangrove plantations across the world. Climatic factors, proxies of edaphic factors, as well as biological factors (e.g. mangrove species) were included as explanatory variables in the analyses to determine factors influencing the global patterns of tree growth rate and stand wood production of mangroves. Using hierarchical Classification and Regression Tree (CART) analysis we found interactions among environmental and biological factors in controlling mangrove tree growth rate and stand wood production. We also found different global patterns of tree growth rate and stand wood production between non-plantation mangroves and plantations. Climatic conditions (precipitation of driest season, precipitation seasonality) were the most important factors influencing the global pattern of tree DBH growth rate in non-plantation mangroves, with edaphic and biological characteristics also playing a role under specific climatic conditions. The global pattern of stand wood production in non-plantation mangroves was primarily determined by stand mean DBH growth rate of individual trees. However, in mangrove plantations management measures, specifically species selection and planting density, were the most important factors influencing the global patterns of tree growth rate and stand wood production. Our study provides parameters for a global estimation of long-term carbon sequestration in both non-plantation mangroves and mangrove plantations. In addition, our results help us better predict the dynamics of tree growth and carbon sequestration of non-plantation mangroves under changing climate.

Forest Ecology and Management

Reviews and syntheses: Variable inundation across Earth's terrestrial ecosystems

The structure, function, and dynamics of Earth's terrestrial ecosystems are profoundly influenced by how often (frequency) and how long (duration) they are inundated with water. A diverse array of natural and human-engineered systems experience temporally variable inundation whereby they fluctuate between inundated and non-inundated states. Variable inundation spans extreme events to predictable sub-daily cycles. Variably inundated ecosystems (VIEs) include hillslopes, non-perennial streams, wetlands, floodplains, temporary ponds, tidal systems, storm-impacted coastal zones, and human-engineered systems. VIEs are diverse in terms of inundation regimes, water chemistry and flow velocity, soil and sediment properties, vegetation, and many other properties. The spatial and temporal scales of variable inundation are vast, ranging from sub-meter to whole landscapes and from sub-hourly to multi-decadal. The broad range of system types and scales makes it challenging to predict the hydrology, biogeochemistry, ecology, and physical evolution of VIEs. Despite all experiencing the loss and gain of an overlying water column, VIEs are rarely considered together in conceptual, theoretical, modeling, or measurement frameworks and approaches. Studying VIEs together has the potential to generate mechanistic understanding that is transferable across a much broader range of environmental conditions, relative to knowledge generated by studying any one VIE type. We postulate that enhanced transferability will be important for predicting changes in VIE function in response to global change. Here we aim to catalyze cross-VIE science that studies drivers and impacts of variable inundation across Earth's VIEs. To this end, we complement expert mini-reviews of eight major VIE systems with overviews of VIE-relevant methods and challenges associated with scale. We conclude with perspectives on how cross-VIE science can derive transferable understanding via unifying conceptual models in which the impacts of variable inundation are studied across multi-dimensional environmental space.

Biogeosciences

Leveraging artificial intelligence and machine learning to advance Chesapeake Bay research and management: A review of status, challenges, and opportunities

The Chesapeake Bay and its watershed (hereafter “Chesapeake Bay region”) have been the focus of extensive restoration efforts for several decades. These restoration efforts are guided by the Chesapeake Bay Watershed Agreement (Chesapeake Executive Council 2014) which outlines 10 goals and 31 measurable outcomes. The Chesapeake Bay is globally recognized as a model for coastal restoration due to long-term investments in monitoring, modeling, implementation and research by the Chesapeake Bay Program (CBP) partnership. These monitoring network spans tidal and non-tidal regions and provides data across multiple scales. Artificial intelligence (AI), particularly machine-learning (ML) and deep learning (DL), has emerged as a powerful tool for analyzing large, complex datasets. These techniques have gained widespread adoption across various disciplines, including ecology, hydrology, and environmental science. In the Bay context, AI/ML is increasingly being used to explore drivers of environmental change, analyze system dynamics, and predict conditions in areas with limited monitoring. The CBP partnership, particularly its Scientific and Technical Advisory Committee (STAC), has increasingly recognized the growing role of AI/ML in watershed and estuarine management. Recent Chesapeake Community Research Symposium sessions and initiatives such as the Chesapeake Global Collaboratory highlight increasing regional momentum to apply big data and AI/ML for environmental solutions. Together, these developments underscore the timely need to explore how AI/ML can help advance Chesapeake Bay restoration and management. This STAC workshop, titled “Leveraging Artificial Intelligence and Machine learning to Advance Chesapeake Bay Research and Management: A review of status, challenges, and opportunities,” was held from February 24-25, 2025, in Edgewater, Maryland to bring together over 50 federal, state, and academic scientists and partners to synthesize the current state of AI/ML applications and identify research gaps in Chesapeake Bay research and management. The workshop focused on three main objectives: 1. Summarize recent AI/ML applications and lessons learned in both tidal and nontidal areas of the Chesapeake Bay region. 2. Identify challenges and gaps in applying AI/ML approaches to Chesapeake Bay data. Such challenges and gaps may include data limitations, harmonization issues, ineffective communication of AI/ML insights, and a lack of coordination among research and management institutions. 3. Develop recommendations and identify opportunities for leveraging AI/ML to address issues across the Chesapeake Bay region. Key areas of focus may include generating new information to support watershed management, delivering AI/MLgenerated insights to managers in a clear and actionable way, and fostering greater collaboration among stakeholders within the CBP Partnership. Workshop participants engaged in science presentations and breakout sessions to develop recommendations for advancing the integration of AI/ML techniques into research and management across the Chesapeake Bay region. By synthesizing current applications, identifying challenges, and exploring new opportunities, the workshop has provided valuable insights and recommendations for better leveraging AI/ML approaches to support the success of Bay restoration efforts. Together, these recommendations provide a roadmap for enhancing data-driven, science-based decision making aligned with the goals and outcomes of the Chesapeake Bay Watershed Agreement.

Delaware, Maryland, Virginia

Genetic diversity is considered important but interpreted narrowly in country reports to the Convention on Biological Diversity: Current actions and indicators are insufficient

International agreements such as the Convention on Biological Diversity (CBD) have committed to conserve, and sustainably and equitably use, biodiversity. The CBD is a vital instrument for global conservation because it guides 195 countries and the European Union in setting priorities and allocating resources, and requires regular reporting on progress. However, the CBD and similar policy agreements have often neglected genetic diversity. This is a critical gap because genetic diversity underlies adaptation to environmental change and ecosystem resilience. Here we aim to inform future policy, monitoring, and reporting efforts focused on limiting biodiversity loss by conducting the largest yet evaluation of how Parties to the CBD report on genetic diversity. A large, globally representative sample of 114 CBD National Reports was examined to assess reported actions, progress, values and indicators related to genetic diversity. Although the importance of genetic diversity is recognized by most Parties to the CBD, genetic diversity targets mainly addressed variation within crops and livestock (a small fraction of all species). Reported actions to conserve genetic diversity primarily concerned ex situ facilities and legislation, rather than monitoring and in situ intervention. The most commonly reported status indicators are not well correlated to maintaining genetic diversity. Lastly, few reports mentioned genetic monitoring using DNA data, indigenous use and knowledge of genetic diversity, or development of strategies to conserve genetic diversity. We make several recommendations for the post-2020 CBD Biodiversity Framework, and similar efforts such as IPBES, to improve awareness, assessment, and monitoring of genetic diversity, and facilitate consistent and complete reporting in the future.

Biological Conservation

Beyond clay: Towards an improved set of variables for predicting soil organic matter content

Improved quantification of the factors controlling soil organic matter (SOM) stabilization at continental to global scales is needed to inform projections of the largest actively cycling terrestrial carbon pool on Earth, and its response to environmental change. Biogeochemical models rely almost exclusively on clay content to modify rates of SOM turnover and fluxes of climate-active CO 2 to the atmosphere. Emerging conceptual understanding, however, suggests other soil physicochemical properties may predict SOM stabilization better than clay content. We addressed this discrepancy by synthesizing data from over 5,500 soil profiles spanning continental scale environmental gradients. Here, we demonstrate that other physicochemical parameters are much stronger predictors of SOM content, with clay content having relatively little explanatory power. We show that exchangeable calcium strongly predicted SOM content in water-limited, alkaline soils, whereas with increasing moisture availability and acidity, iron- and aluminum-oxyhydroxides emerged as better predictors, demonstrating that the relative importance of SOM stabilization mechanisms scales with climate and acidity. These results highlight the urgent need to modify biogeochemical models to better reflect the role of soil physicochemical properties in SOM cycling.

Biogeochemistry