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Resource assessments constitute a key part of the USGS mission, and represent a crucial contribution toward Department of the Interior (DOI) and broader Federal objectives. Current USGS energy and mineral assessment methods evaluate total technically recoverable resources (energy) or economically exploitable materials (minerals); the fiscal year 2010 budget for this work is $82M. To help stakeholders respond to escalating national and worldwide demand for energy, mineral, water, and biological resources, the USGS will expand existing assessment methods to include the environmental and human-health impacts of resource extraction and use, along with multi-resource dependencies and conflicts. This Powell Center working...
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While it is widely recognized that microorganisms are intimately linked with every biogeochemical cycle in all ecosystems, it is not clear how and when microbial dynamics constrain ecosystem processes. As a result, it is know clear how to apply the value of increasingly detailed characterization of microbial properties to our understanding of ecosystem ecology. Several recent papers have demonstrated how information about microbial dynamics can be incorporated into ecosystem models (Allison et al. 2010, McGuire and Treseder 2010, Todd - Brown et al. 2011a), but it is generally not clear what types of microbial data are most useful in explaining variation in biogeochemical processes and ecosystem functioning, especially...
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The transport of dissolved organic matter (DOM) by rivers is an important component of the global carbon cycle, affects ecosystems and water quality, and reflects biogeochemical and hydrological processes in watersheds. Understanding the fundamental relationships between discharge and DOM concentration and composition reveals important information about watershed flow paths, soil flushing, connectivity to riparian zones, organic matter leaching, soil moisture, and climatic influences. Data to describe these processes - both magnitude and timing - is critical for modeling and predicting watershed DOM dynamics, particularly in light of land use and climate change . Despite several decades of data collection, a synthesis...
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One of the grand challenges of Earth Surface Science and Natural Resource Management lies in the prediction of mass and energy transfer for large watersheds and landscapes. High resolution topography (lidar) datasets show potential to significantly advance our understanding of hydrologic and geomorphic processes controlling mass and energy transfer because they represent features at the appropriate fine scale on which surface processes operate. While lidar datasets have become readily available across the United States, challenges remain in extracting accurate and objective information relevant for hydrologic and geomorphic research, modeling, and prediction, as well as watershed management. We primarily focus our...
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Advances in new technologies such as remote cameras, noninvasive genetics and bioacoustics provide massive quantities of electronic data. Much work has been done on automated (“machine learning”) methods of classification which produce “sample class designations” (e.g., identification of species or individuals) that are regarded as observed data in ecological models. However, these “data” are actually derived quantities (or synthetic data) and subject to various important sources of bias and error. If the derived quantities are used to make ecological determinations without consideration of these biases, those inferences which inform monitoring, conservation, and management will be flawed. We propose to develop...
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Climate change is expected to cause more intense and frequent extreme weather events, but we only have a basic understanding of how these events might alter freshwater systems. Storms are likely to impact lake systems through delivery of sediments from watersheds and mixing of the water column, both of which could have important consequences for phytoplankton. Phytoplankton are the base of the food web; their community configuration and how the community changes across seasons have large impacts on ecosystem processes such as energy flow, nutrient cycling, and carbon cycling. External disturbances may abruptly alter phytoplankton community dynamics and thus impact ecosystem function. The effects of storms on the...
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The goal of this Powell Center Working Group is to produce a collection of vetted and standardized earthquake and landslide tsunami sources that can be used to produce the meaningful hazard assessment products required for effective tsunami hazard mitigation and risk reduction. The need for a set of realistic and consistent tsunami sources was identified as a high priority at a 2016 workshop between USGS scientists and the National Tsunami Hazards Mitigation Program (NTHMP). The Powell Center Working Group will include scientists from the USGS, NOAA, the NTHMP, academia, and consulting companies. Tsunamis are extreme events that have caused devastation worldwide over the past several decades. The tsunami from...
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The Cascadia Subduction Zone, located in the U.S. Pacific Northwest and southwestern British Columbia, has hosted magnitude ≥8.0 megathrust earthquakes in the geologic past, a future earthquake is imminent, and the potential impacts could cripple the region. Subduction zone earthquakes represent some of the most devastating natural hazards on Earth. Despite substantial knowledge gained from decades of geoscience research, the size and frequency of Cascadian earthquakes remain controversial, as do the physics of earthquake rupture, the effects of earthquake shaking, and the effect of resultant tsunamis. This translates into major uncertainties in earthquake hazard assessments that can lead to ineffective preparedness...
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Streamflow is declining in many parts of the United States (US) due to factors including groundwater pumping, land use change, and climate change. Streamflow depletion, a reduction in groundwater discharge to a stream due to human activities such as pumping and/or land use change, tends to evolve slowly and can be entirely invisible for many years to decades. This is because streamflow depletion can be masked by the natural and/or climate change-induced variability in streamflow, and groundwater storage can buffer the impacts on streams. The negative effects on both anthropogenic and ecological systems can evolve over decades or more, and specific causes and potential solutions to these issues are often difficult...
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Forests sequester the majority of the terrestrial biosphere’s carbon and are key components of the global carbon cycle, potentially contributing substantial feedbacks to ongoing climatic changes. It is therefore remarkable that no consensus yet exists about the fundamental nature of tree mass growth (and thus carbon sequestration rate). Specifically, does tree mass growth rate increase, decrease, or stay the same with increasing tree size? The answer could have profound implications for our ability to forecast the role of forests in the global carbon cycle and to devise appropriate adaptation and mitigation strategies for forests in the face of rapid climatic changes. We will conduct the first global-scale characterization...
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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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The three-dimensional (3D) form of the Earth’s surface results from both abiotic and biotic forces. Major abiotic forces, such as tectonic uplift, erosion, and climate, exert strong influence over land surface morphology. Biotic forces, including, significantly, humans, also shape the landscape, but often at different temporal and spatial scales and magnitudes than geologic forces. Because the processes shaping the land surface, as expressed in its topography, are ongoing, topographic change is ever present and is a factor that must be broadly considered in studies of natural and built environments. Remote sensing data, especially in the form of derived high-resolution measurements of the topography, have been widely...
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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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USGS PRISM (Pliocene Research, Interpretation and Synoptic Mapping) Project global data sets of Pliocene conditions, which form the most comprehensive global reconstruction for any warm period prior to the recent past, are used to drive numerical climate model simulations designed to explore the impact of climate forcings and feedbacks during the Pliocene. The Pliocene world provides an unequaled paleo-­‐laboratory to test the sensitivity of the physical models that estimate the impacts of future warming and challenges our understanding of the sensitivity of key components of the climate system and how they are simulated (e.g., polar vs. tropical sensitivity, the role of ocean circulation in a warming climate, the...
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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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A vast number of the world’s volcanoes are unmonitored by ground-based sensors, yet constitute an important hazard to nearby residents and infrastructure, as well as air travel and the global economy. Satellite data provide a cost-effective means of tracking activity at such volcanoes. Unfortunately, satellite acquisitions are not optimized for application to volcano hazards, in part because clear relations between satellite-monitored unrest and eruptive activity are lacking. We aim to bridge this gap by developing linked global databases of satellite observations of volcanic activity, with the goal of relating surface change and volcanic emissions to eruption style and impact. This database (or databases) will...
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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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Groundwater contaminated with naturally occurring arsenic is a widespread problem affecting many alluvial and deltaic aquifer systems throughout the world. The human health toll from consuming groundwater with high levels of arsenic is staggering in its proportions. Furthermore, the use of arsenic contaminated groundwater for irrigation is observed to result in diminished crop yields and thus poses a threat to food security in arsenic affected regions. Decades of research at individual field sites have resulted in the collection of many geochemical and geologic datasets. A key feature of alluvial and deltaic aquifer systems is the large degree of spatial variability in groundwater arsenic concentrations from local...