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Folders: ROOT > ScienceBase Catalog > John Wesley Powell Center for Analysis and Synthesis ( Show all descendants )

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It is well know that every earthquake can spawn others (e.g., as aftershocks), and that such triggered events can be large and damaging, as recently demonstrated by L’Aquila, Italy and Christchurch, New Zealand earthquakes. In spite of being an explicit USGS strategic-action priority (http://pubs.usgs.gov/of/2012/1088; page 32), the USGS currently lacks an automated system with which to forecast such events and official protocols for disseminating the potential implications. This capability, known as Operational Earthquake Forecasting (OEF), could provide valuable situational awareness to emergency managers, the public, and other entities interested in preparing for potentially damaging earthquakes. With the various...
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There has been increasing attention placed on the need for water availability information at ungauged locations, particularly related to balancing human and ecological needs for water. Critical to assessing water availability is the necessity for daily streamflow time series; however, most of the rivers in the United States are ungauged. This proposal leverages over $1M currently allocated to the USGS National Water Census Program towards developing an integrated modeling approach to estimate daily streamflow at ungauged locations, with the ultimate goal of providing daily streamflow estimates at 160,000 ungauged catchments across the United States. By assembling a diverse and prolific group of international scientists,...
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Advancing our mechanistic understanding of ecosystem responses to climate change is critical to improve ecological theories, develop predictive models to simulate ecosystem processes, and inform sound policies to manage ecosystems and human activities. Manipulation of temperature in the field, or the “ecosystem warming experiment,” has proved to be a powerful tool to understand ecosystem responses to changes in temperature. No comprehensive synthesis has been conducted since the last one more than 10 years ago. A new synthetic analysis is critically needed to advance our understanding of ecosystem responses to warming, to highlight experimental artifacts and appropriate interpretations, and to guide development...
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Shale gas is a key source of onshore domestic energy for the United States and production of this resource is increasing rapidly. Development and extraction of shale gas requires hydraulic fracturing, which entails horizontal drilling, perforation of steel casing and cement grout using explosive charges, and expansion of fractures using fluids under high pressure. Concern over potential environmental effects of shale gas development is growing and based on a recent review there is very little information in the scientific literature on potential environmental effects of hydraulic fracturing. We propose to conduct the first broad scale, data-based assessment of the potential effects of hydraulic fracturing on water...
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Tropical forests contain > 50% of the world’s known species (Heywood 1995), 55% of global forest biomass (Pan et al. 2011), and exchange more carbon (C), water and energy with the atmosphere than any other ecosystem type (e.g., Saugier et al. 2001). Despite their importance, there is more uncertainty associated with predictions of how tropical forests will respond to warming than for any other biome (Randerson et al. 2009). This uncertainty is of global concern due to the large quantity of C cycled by these forests and the high potential for biodiversity loss. Given the importance of tropical forests, decision makers and land managers around the globe need increased predictive capacity regarding how tropical forests...
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Amphibian populations are declining globally at unprecedented rates but statistically rigorous identification of mechanisms is lacking. Identification of reasons underlying large-scale declines is imperative to plan and implement effective conservation efforts. Most research on amphibian population decline has focused on local populations and local factors. However, the ubiquity of declines across species and landscapes suggests that causal factors at a broader scale are also important. Elucidation of the mechanisms driving population change has lagged, mainly because data have been unavailable at continental scales. We propose to address this need by assembling data to answer questions about broad-scale drivers...
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Ecosystems are changing worldwide and critical decisions that affect ecosystem health and sustainability are being made every day. As ecologists, we have a responsibility to ensure that these decisions are made with access to the best available science. However, to bring this idea into practice, ecology needs to make a substantial leap forward towards becoming a more predictive science. Furthermore, even for basic, conceptual questions there is a lot to be gained by addressing problems from a forecasting perspective, with more frequent data-model comparisons helping to highlight misunderstandings and reframe long-standing questions. Ecological forecasting is occurring across a wide range of ecological sub-disciplines,...
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Non-native insect invasions increasingly cause widespread ecological and economic damage in natural and agricultural ecosystems. Non-native insects specialized for feeding on specific plant groups are particularly problematic as they can potentially eliminate an entire genus of native plant species across a wide area. For example, emerald ash borer has killed hundreds of millions of ash trees in North America since its accidental introduction from Asia, including more than 99% of all trees in forests near the epicenter of the invasion. However, most introduced insects do not become high-impact pests. Our goal is to develop a framework that allows us to predict whether non-native herbivorous insects in natural ecosystems...
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Global hydroclimatic conditions have been significantly altered, over the past century, by anthropogenic influences that arise from warming global climate and also from local/regional anthropogenic disturbances. There has been never been an effort that has systematically analyzed how the spatio-temporal variability of land-surface fluxes vary in natural and human-altered watersheds globally. This synthesis study will adapt and extend the classical Budyko framework to quantify the role of drivers - changing climate and local human disturbances - in altering flow regimes and in creating urban heat island episodes over the globe. An allied goal is to develop parsimonious hydroclimatic models that explain the spatio-temporal...
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Migratory species may provide more ecosystem goods and services to humans in certain parts of their range than others. These areas may or may not coincide with the locations of habitat on which the species is most dependent for its continued population viability. This situation can present significant policy challenges, as locations that most support a given species may be in effect subsidizing the provision of services in other locations, often in different political jurisdictions. The ability to quantify these spatial subsidies could be used to develop economic incentives that internalize the costs and benefits of protecting migratory species, enhancing cross-jurisdictional cooperative management. Targeted payments...
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Models that predict the flow of rivers and streams are critically important for planning flood control, hydropower, and reservoir operations, as well as for management of fish and wildlife populations. As temperatures and precipitation regimes change globally, the need to improve and develop these models for a wider spatial coverage and higher spatial fidelity becomes more imperative. Currently, one of the biggest impediments to developing robust streamflow knowledge is incomplete understanding of the range of timescales over which water is stored (e.g., in snowpack, soils, and groundwater) in watersheds, as well as the processes and factors that control those storage timescales. This working group will address...
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Nitrogen deposition is altering forest dynamics, terrestrial carbon storage, and biodiversity. However, our ability to forecast how different tree species will respond to N deposition, especially key response thresholds, is limited by a lack of synthesis across spatial scales and research approaches. To develop our best understanding of N deposition impact on tree growth and survival, we will integrate plot-­‐ level studies describing plant growth and survival responses to N inputs and plant-­‐ available soil nutrients with a continental scale analysis across a N deposition gradient. Our primary outcome will be estimates of tree response to N deposition with explicit representation of uncertainty and the identification...
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The past decade has seen improvements in computational efficiency, seismic data coverage, and communication technology - driven by societal expectation for timely, accurate information. While aspects of earthquake research have taken advantage of this evolution, the adoption of improvements in earthquake monitoring has not been fully leveraged. In real-time monitoring, earthquakes are characterized in a vacuum, without building upon our knowledge of past events. New data types may help characterize earthquakes more quickly and accurately. New opportunities exist for rapidly communicating information. With these advances, global seismic monitoring can improve the quality and timeliness of information shared with...
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Soils are a vast reservoir of organic carbon (C), rendering the fate of soil C an important control on the global climate system. Widespread changes in soil C storage capacity present a potentially strong feedback to global change. Yet, a comprehensive understanding of how soil C will respond to climate and/or land use disturbance remains illusive, resulting in major uncertainties in global climate models. Our working group will synthesize information on the processes controlling soil C storage across different spatial scales and develop new procedures to translate local measurements to the regional and global scale datasets used by models. These activities will improve our ability to map the vulnerability of soil...
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Geographically Isolated Wetlands (GIWs) occur along gradients of hydrologic and ecological connectivity and isolation, even within wetland types (e.g., forested, emergent marshes) and functional classes (e.g., ephemeral systems, permanent systems, etc.). Within a given watershed, the relative positions of wetlands and open-waters along these gradients influence the type and magnitude of their chemical, physical, and biological effects on downgradient waters. In addition, the ways in which GIWs connect to the broader hydrological landscape, and the effects of such connectivity on downgradient waters, depends largely upon climate, geology, and relief, the heterogeneity of which expands with increasing scale. Developing...
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River ecosystems support a wide diversity of biota, including thousands of fish species, which are variously adapted to the dynamic environments provided by flowing-water habitats. One of the primary ways that human activities diminish the biological capacity of rivers is by altering the natural hydrologic variability of river systems through regulation and diversion of streamflow for other uses. Managers may be able to avoid some of the worst effects of flow management on aquatic biota if we understand the mechanisms by which streamflow components, such as unusually high and low flow events, affect populations (e.g., by influencing recruitment and mortality). Numerous past studies have described correlative associations...
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Wetlands provide many important ecosystem services, including wildlife habitat, water purification, flood protection, and carbon metabolism. Our ability to manage these services and predict the long-term health of wetlands is strongly linked to their carbon fluxes, of which methane (CH4) is a key component. Natural wetlands emit approximately 30% of global CH4 emissions, as their waterlogged soils create ideal conditions for CH4 production. They are also the largest, and potentially most uncertain, natural source of CH4 to the atmosphere. To understand and predict CH4 fluxes across wetlands globally, we propose the first synthesis of CH4 flux tower data accompanying a global database of CH4 emissions. By taking...
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Fresh water is arguably the most valuable resource on the planet, but human activities threaten freshwater ecosystems. For example, use of synthetic chemicals, such as pesticides, road salts, and nutrients, has led to the ubiquitous contamination of aquatic systems, jeopardizing the integrity of ecological communities. Given the importance biodiversity plays in maintaining ecosystem health and function and the continued decline of freshwater species, it is vital to understand the direct, indirect, and lasting effects of synthetic contaminants on biota in freshwater systems. The majority of our knowledge regarding contaminant effects is comprised of short-term, single-contaminant laboratory toxicity tests that describe...
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