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Mercury (Hg) is a serious environmental problem that is impacting ecological and human health on a global scale. However, local and regional processes are largely responsible for producing methylmercury, which drives ecological risk. This is particularly true in western North America where the combination of diverse landscapes, habitat types, climates, and Hg sources may disproportionally impact the region relative to other areas in North America. Even with decades of regional Hg research and monitoring, there is still no holistic synthesis of the spatiotemporal patterns of Hg in abiotic and biotic resources across the region, nor has there been a formal, simultaneous analysis of the landscape, ecological and climatological...
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Dam decommissioning is rapidly emerging as an important river restoration strategy in the U.S., with several major removals recently completed or in progress. But few studies have evaluated the far-reaching consequences of these significant environmental perturbations, especially those resulting from removals of large (>10-15 m tall) structures during the last decade. In particular, interactions between physical and ecological aspects of dam removal are poorly known. From recent work, however, observations are now available from several diverse settings nationwide to allow synthesis of key physical and ecological processes associated with dam removals, including fish and benthic community response, reservoir erosion,...
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There is a wealth of biodiversity and environmental data that can provide the basis for addressing global scale questions of societal concern. However, our ability to access and integrate this data is hampered by the lack of standardized languages and systems to make this information accessible through the Internet. New tools (e.g. ontologies, standards, integration tools, unique identifiers) are being developed that will move this process closer to establishing a framework for linked open data, but these tools are still nascent and require efforts in the biodiversity and environmental realm to bring to fruition, as has occurred in other domains (e.g. biomedicine). With the right data modeling and tools, data assembly...
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Drylands are integral to the Earth system and the present and future of human society. Drylands encompass more than 40% of the terrestrial landmass and support 34% of the world’s human population. Biocrusts are the “living skin” of Earth’s drylands, sometimes dominating the ground cover and figuring prominently in ecosystem structure and function. Biocrusts are a biological aggregate of cyanobacteria, fungi, algae, lichens and mosses in the surface millimeters of soil. By aggregating soil, biocrusts make sediment less erodible. They also strongly influence the water runoff-infiltration balance. In some ecosystems they generate runoff, whereas in other systems they enhance water capture. Vascular plant germination,...
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This proposal brings together biologists and geoscientists to evaluate the evolution of stress tolerance and adaptation to extreme environments in plants. Stress tolerance has been studied mainly from a physiological perspective using laboratory and field experiments. In contrast, this project will take a combined environmental and evolutionary perspective using national public databases and a “big data” approach. Thus the proposal will illustrate an application of spatially integrated big datasets for basic research, a synthesis goal of the Powell Center. We will use the geochemical and mineralogical data from the USGS Soil Geochemical Landscapes of the Conterminous United States Project, digital elevation and...
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Terrestrial evapotranspiration (ET), the second-largest component of the terrestrial water cycle, links water, energy, and carbon cycles and influences the productivity and health of our ecosystems. Despite the importance of ET, the dynamics of ET across a spectrum of spatiotemporal scale and their controls are uncertain. During an international ET workshop held in November 2021 by AmeriFlux, the scientific community identified key challenges to improve our understanding of ET dynamics. Participants underscored the need for an integrated understanding of ET across the different research disciplines: in-situ measurements, remote sensing, and modeling. Here, we propose the synthesis of the three research areas to...
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Despite the critical services freshwater systems provide, freshwater biodiversity has been vastly under-studied compared to terrestrial and marine biomes. In fact, systematic compilations of freshwater zooplankton are surprisingly rare despite the critical roles zooplankton play in regulating and supporting ecosystem services, serving as key indicator species, and consequently, influencing emergent system properties such as water quality and food web structure. We have compiled and harmonized the most temporally and spatially extensive freshwater zooplankton dataset available to date, designed to seamlessly integrate with a suite of in-lake and remote sensing data and modeling products. Our international team will...
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The role of lynx dispersal in maintaining their populations at the landscape scale is unclear. A large proportion of local lynx populations are known to disperse following a snowshoe hare population crash, but whether these dispersal events contribute to the cyclic dynamics of neighboring populations is not well understood. If lynx dispersal does play an important role in lynx population dynamics then the conservation of dispersal corridors is critical to maintaining those dynamics. However, we currently have no information on the habitat requirements of dispersing lynx in relation to human land use, such as housing developments, road building, timber harvest, and mining, all of which could have a substantial impact...
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The Lakewide Management Plans (LaMPs) within the Great Lakes region are examples of broad-scale, collaborative resource-management efforts that require a sound ecosystems approach. Yet, the LaMP process is lacking a holistic framework that allows these individual actions to be planned and understood within the broader context of the Great Lakes ecosystem. To help this issue, a conceptual framework for Lake Michigan Coastal/Nearshore Ecosystems was developed to address for major LaMP goals; Can we drink the water?, Can we eat the fish?, Can we swim in the water?, Are all habitats healthy, naturally diverse, and sufficient to sustain viable biological communities?
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The impacts of nitrogen (N) deposition on plant diversity loss have been well documented across N deposition gradients in Europe, but much less so in the U.S. Published N fertilizer studies suggest losses will occur in the US, but many of these were done at levels of N input that were higher than modeled and measured N deposition, and higher than presumed N critical loads. The recent availability of modeled N deposition across the U.S. (e.g. using CMAQ) has provided a high‐resolution tool to identify regions where steep N deposition gradients facilitate detection of ecological shifts. A number of plant diversity (richness plus abundance) data sets across the U.S. have explained diversity shifts based on anthropogenic...
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Streams and rivers have a limited spatial extent, but are increasingly recognized as key components of regional biogeochemical cycles. The collective metabolic processing of organisms, known as ecosystem metabolism, is centrally important to nutrient cycling and carbon fluxes in these environments, but is poorly integrated into emerging biogeochemical concepts. This line of inquiry lags behind other aspects of regional biogeochemistry because of the lack of long-term, regionally-diverse studies of stream metabolism. With a few exceptions, metabolism studies have focused on small headwater catchments using short-term (days to weeks) observation. As a consequence, basic patterns and controls of this fundamental process,...
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Subsurface preferential flow (PF = water bypassing the soil matrix) provides rapid flowpaths for water and any substances transported with it, thereby profoundly impacting the recharge of aquifers, the spreading of contaminants, the health of the soil, and the functioning of ecosystems. It involves a complexity of processes that are poorly understood to the degree that current science provides no reliable way to predict its occurrence and magnitude. This effort will address the fundamental question of where and when PF occurs, taking advantage of two recent scientific developments: availability of high frequency (at least every 30 minutes), multi-depth soil moisture data suitable to detect preferential flow events...
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Rivers are the veins of the landscape, providing environmental benefits that are disproportionately high relative to their aerial extent; shedding flood waters, hosting aquatic ecosystems, transporting solutes and energy-rich materials, and storing and transforming pollutants into less harmful forms. From uplands to the coasts, rivers facilitate key biogeochemical reactions that cumulatively influence water quality. Many of the reactions are optimized outside the main channel, in hyporheic zones, riparian zones, and floodplain areas, where riverine water is in close contact with geochemically and microbially-active sediments. However, little is known about the distribution, intermittency, and overall effectiveness...
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Current land use practices have affected ecosystem structure and processes in ways that have degraded delivery of key ecosystem services controlling exchanges of carbon and nitrogen with the atmosphere and surface and groundwater systems. These impacts are observed in the emissions of greenhouse gases (GHG) and N pollution in our nation’s water systems and coastal areas. Improvements in databases of climate, soils, and land use practices in the north central Great Plains (i.e., NCGP: Colorado, Kansas, Wyoming, Nebraska, Montana, South Dakota, and North Dakota) provide a unique opportunity for integration and synthesis of this information on the exchanges of C and N affecting our environmental resources. In addition,...
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The timing of breeding is constrained in Arctic ecosystems and small temporal differences in when individuals breed can have large effects on fitness. Arctic ecosystems are generally warming more rapidly than other ecosystems which, for migratory species, can cause an imbalance, or mismatch, between when they have evolved to breed versus when it is optimal to breed environmentally. Geese are abundant herbivores summering in tundra ecosystems, and whose presence has important feedbacks on ecosystem processes. Some goose populations have already exhibited signs that spring vegetation phenology is occurring earlier than individuals are able to breed, with a consequent effect on their reproductive fitness. The magnitude...
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Coral reefs are massive, wave resistant structures found throughout the tropics, where they have long attracted attention for their beauty, ecological importance, and rich biological diversity. However, in recent years attention to these systems has focused on their downturn in health and the potential that they effectively could disappear within a century. Yet while many coral reefs have deteriorated, a small number have flourished and now represent “oases” with the potential to drive repopulation of the denuded areas that surround them. This working group focuses on the geographic, biological, ecological, and physical features that characterize oases in coral reef communities, and evaluates the potential of...
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Global climate change is putting unprecedented pressure on global croplands and their water use, vital for ensuring future food security for the world's rapidly expanding human population. The end of the green green revolution (productivity per unit of land) era has meant declining global per capita agricultural production requiring immediate policy responses to safeguard food security amidst global climate change and economic turbulence. Above all, global croplands are water guzzlers, consuming between 60-90% of all human water use. With increasing urbanization, industrialization, and other demands (e.g., bio-fuels) on water there is increasing pressure to reduce agricultural water use by producing more food from...
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Projecting the effects of climate change on plant and animal species distributions and abundance is critical to successful long‐term conservation and restoration efforts. There have been significant recent advances made in the areas of: (1) climate forecasts; (2) habitat niche modeling; (3) mechanistic modeling; and (4) observation techniques and networks. However, projections of biological change are fundamentally limited by a lack of integration and inter‐comparison between these various forecasting approaches. The proposed working group will focus on integrating ecological forecasting methods for two well studied invasive species: cheatgrass (Bromus tectorum) and gypsy moth (Lymantria dispar). Our goal is to...
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Our ability to effectively manage natural resources is founded in an understanding of how our actions and the environment influence populations, communities, and ecosystems. Current practices use monitoring data from the past to determine key ecological relationships and make predictions about the future with the assumption that those relationships will remain constant. However, many natural systems are undergoing rapid changes due to external factors including climate change, urbanization, and energy development, leading to a situation in which our observations of the past are poor predictors of the future. Ignoring such changes could lead to management decisions that are sub-optimal at best or detrimental at worst....
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Drought impacts on terrestrial ecosystems have increased globally in the 21st century, and droughts are expected to become more frequent, extreme, and spatially extensive in the future. Historical site-based observations are inadequate to predict how future extreme water deficits will affect the global terrestrial surface, because future droughts and their impacts may be more extreme than they have been historically and reach well beyond a single ecosystem. This USGS Powell Center working group will conduct the first comprehensive synthesis of ecosystem impacts across a coordinated, globally distributed drought experiment network of over 100 sites that have imposed an extreme multi-year drought. Knowledge about...


map background search result map search result map Global Croplands and Their Water Use for Food Security in the Twenty-first Century Lakewide Management Plan Capacity Support by U.S. Geological Survey - LAKE MICHIGAN Movement Patterns, Dispersal Behavior, and Survival of Lynx in Relation to Snowshoe Hare Abundance in the Boreal Forest Lakewide Management Plan Capacity Support by U.S. Geological Survey - LAKE MICHIGAN Movement Patterns, Dispersal Behavior, and Survival of Lynx in Relation to Snowshoe Hare Abundance in the Boreal Forest