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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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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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Despite the best monitoring networks, the highest rate of earthquakes and the longest continuous recorded history in the world, this year’s M=9.0 Tohoku, Japan, earthquake was completely unforeseen. The Japanese had expected no larger than a M=8 quake in the Japan trench, 1/30 th the size of the Tohoku temblor. This year also saw the devastating M=6.3 Christchurch, New Zealand earthquake and the M=5.8 Virginia quake, and it marks the bicentennial of the enigmatic but destructive 1811 - 1812 M~7 ½ New Madrid, Missouri, earthquakes, each event an example of how poorly we can forecast earthquake rates or their ultimate size in the planet’s vast intraplate regions far from plate boundaries. The goal of the Global...
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Water cycling and availability exert dominant control over ecological processes and the sustainability of ecosystem services in water - limited ecosystems. Consequently, dryland ecosystems have the potential to be dramatically impacted by hydrologic alterations emerging from global change, notably increasing temperature and altered precipitation patterns. In addition, the possibility of directly manipulating global solar radiation by augmenting stratospheric SO2 is receiving increasing attention as CO2 emissions continue to increase - these manipulations are anticipated to decrease precipitation, a change that may be as influential as temperature increases in dryland ecosystems. We propose to integrate a proven...
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Groundwater withdrawals in the western US are a critical component of the water resources strategy for the region. Climate change already may be substantially altering recharge into groundwater systems; however, the quantity and direction (increase or decrease) of changes are relatively unknown as most climate change assessments have focused on surface water systems. We propose to conduct a broad scale literature review followed by a synthesis of available data, analysis and simulations with available downscaled climate scenarios to understand how recharge in the western US might respond to plausible climatic shifts during the rest of the 21st Century. We will produce an estimated range of impacts on groundwater...
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Biological nitrogen fixation (BNF) is a critical biogeochemical process that converts inert atmospheric N2 gas into biologically usable forms of the essential nutrient nitrogen. A variety of free-living and symbiotic organisms carry out BNF, and in most regions worldwide, BNF is the largest source of nitrogen that fuels terrestrial ecosystems. As a result, BNF has far reaching effects on ecosystem properties (water quality, carbon storage), sustainability (plant growth, soil fertility), and the global climate system. Despite this cross-cutting importance, existing syntheses of BNF have major gaps, with particular challenges in upscaling local measurements across large areas. These gaps, and a corresponding lack...
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A revolution is underway in seismology that transforms fiber-optic cables into arrays of thousands of seismic sensors. Compared to the traditional monitoring networks using inertial seismometers, the fiber-optic approach can increase the spatial data density by orders of magnitude and enable data processing methodologies that require a high-fidelity wavefield. The Working Group aims to advance the USGS, along with several academic and industry partners, towards effective utilization of fiber-optic sensing techniques to understand earthquake hazards and improve monitoring and real-time warning systems. We will conduct synthesis studies that demonstrate the potential gains for various applications, including earthquake...
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Prescribed burning – planned, controlled fires conducted under weather and fuel conditions designed for safety and effectiveness – is a common practice used to maintain and restore native prairies in the Northern Great Plains. However, climate change will affect the number of days in a year, and when, suitable conditions for prescribed fires occur. For instance, warmer temperatures may shift these “good prescribed-fire days” earlier in the spring and later in the fall, but uncertainty about future climate makes it hard to predict how large shifts will be and if the number of good fire days each year will generally increase or decrease. Further, it’s hard to know whether prescribed fires will continue to achieve...
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Invasions of exotic annual grasses (EAGs like cheatgrass have caused major losses of native shrubs and grasses in western U.S. rangelands. They also decrease the productivity and carbon storage in these ecosystems, which is expected to create dryer soils that may cause further losses in plant productivity. This cycle is the hallmark of desertification – or, fertile lands turning into deserts. Management actions that target EAGs are one of the most widespread land management actions taken in Western U.S. rangelands, but it is unclear which specific actions can simultaneously enhance drought resilience of native plant communities and increase carbon sequestration and storage. This project aims to identify the restoration...
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Fibrous erionite, a zeolite mineral, has been designated as a human carcinogen by the World Health Organization and is believed to be the cause of extraordinarily high rates of malignant mesothelioma and other asbestos - related diseases in several villages in Central Turkey. A recent study by the University of Hawaii in collaboration with the U. S. Environmental Protection Agency in Dunn County, North Dakota has demonstrated similar human exposures to fibrous erionite as those in found in Turkey. The source of these exposures is an erionite - bearing volcanic tuff that has been mined, crushed, and used to gravel hundreds of miles of roads. While elevated rates of mesothelioma are not yet apparent in North Dakota,...
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Natural resource managers are coping with rapid changes in both environmental conditions and ecosystems. Enabled by recent advances in data collection and assimilation, short-term ecological forecasting may be a powerful tool to help resource managers anticipate impending changes in ecosystem dynamics (that is, the approaching near-term changes in ecosystems). Managers may use the information in forecasts to minimize the adverse effects of ecological stressors and optimize the effectiveness of management actions. To explore the potential for ecological forecasting to enhance natural resource management, the U.S. Geological Survey (USGS) convened a workshop titled “Building capacity for Applied Short-Term Ecological...
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Estimating species response to environmental change is a key challenge for ecologists and a core mission of the USGS. Effective forecasting of species response requires models that are detailed enough to capture critical processes and at the same time general enough to allow broad application. This tradeoff is difficult to reconcile with most existing methods. We propose to extend and combine existing models that operate at different scales and with different levels of data complexity into a modeling framework that will allow robust estimation of population response to environmental change across a species’ range. This integrated modeling is now possible with the increasing development and application of population...
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Everyone needs clean drinking water in order to thrive. The US EPA and public water purveyors in the US work together in adherence with the Safe Drinking Water Act to make water safe for public consumption. The recent media coverage of lead in public drinking water supplies in Flint, Michigan, and schools in many cities with aging infrastructure throughout the US has raised public awareness of drinking water as a potential pathway of exposure to toxic chemicals. Epidemiologists and other researchers have conclusively shown that high arsenic levels in drinking water in Bangladesh, Taiwan, and South America cause adverse human health outcomes. However, research in study populations with levels of arsenic exposure...
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Ecosystem services - the benefits that nature provides to society and the economy - are gaining increasing traction worldwide as governments and the private sector use them to monitor integrated environmental and economic trends. When they are well understood and managed, ecosystems can provide these long-term benefits to people - such as clean air and water, flood control, crop pollination, and recreational, cultural, and aesthetic benefits. Within the U.S. government, a memo issued by the White House Council on Environmental Quality in October 2015 charged agencies with incorporating these values in planning, investment, and regulatory processes. Natural capital accounting - a tool being used in dozens of countries...
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Groundwater storage depletion is a critical issue for many of the major aquifers in the U.S., particularly during intense droughts. The GRACE (Gravity Recovery and Climate Experiment) satellites launched in 2002, with sensors designed to measure changes in the Earth’s gravitational field at large spatial scales (≥ ~200,000 km2). These changes are primarily driven by changes in water storage on the Earth’s surface. Estimates of groundwater storage changes based on these gravity measurements have attracted considerable media attention in the U.S. and globally. However, groundwater storage changes are computed indirectly by subtracting snow, surface water, and soil moisture storage from the total water storage monitored...
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Resilience science provides a conceptual framework and methodology for quantitatively assessing the ability of a system to remain in a particular state. Probable non-linear ecological responses to global change, including climate change, require a clear framework for understanding and managing resilience. However, much of the resilience research to date has been qualitative in nature, and frameworks developed for the implementation of resilience science have been either vague or focused on the social component of social-ecological systems. Attempts to quantify resilience and operationalize the concept include the cross-scale resilience model, discontinuity theory and the early detection of leading indicators of...
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The pervasive nature of insect species’ declines has led to the specter of an “Insect Armageddon” in the popular press. Insect-derived ecosystem services are valued at > $57 billion in the U.S. and thus the loss of insects has the potential to fundamentally disrupt natural and economic systems.The causes of insect declines have been linked to changes in climate, land use and pesticide use, but there is little consensus on the relative importance of these drivers. There is even less consensus about which species are at most risk and about how to mitigate declines and recover populations. Systematic evaluations of trends across insect taxa in North America are needed as there are none based on systematic monitoring...
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Inland fisheries have tremendous cultural, economic, and subsistence value. However, climate change brings new stresses to land-locked fisheries that raise novel challenges for resource managers. One fundamental challenge in inland fisheries is how to best assess and manage data-limited fisheries when resources are finite and uncertainty is pervasive. To address this challenge, we will use quantitative models to examine whether indicators of fish population status commonly-measured by managers can serve as a “short-cut” to more data- and capacity-intensive approaches. Further, we will work and communicate directly with state and Tribal fisheries managers to better understand the challenges they face when making...
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Scientific information can be used to help individuals, communities, and governments alike make more informed decisions. However, for people to become aware of the science that could inform their decisions and its relevance to their lives and decisions, it must be communicated effectively. Multiple obstacles prevent this from happening, including scientists’ lack of time and communication expertise, among other barriers. This pilot project is a novel internship program that pairs student interns with USGS scientists to assist with field-based natural or physical science research in Alaska, while also providing support to the teams of interns and scientists to generate creative and durable science communication...
map background search result map search result map Climate Effects on Prescribed Fire Implementation and Efficacy in Northern Mixed-Grass Prairie Assessing the Impacts of Rangeland Restoration on Carbon Sequestration and Co-Benefits for Drought Resilience in the Sagebrush Steppe and Mixed Grass Prairie Climate Adaptation for Data-Limited Inland Fisheries Alaska's Changing Habitats: A Multi-System Approach for Understanding Climate Impacts in High Latitude Regions Climate Adaptation for Data-Limited Inland Fisheries Assessing the Impacts of Rangeland Restoration on Carbon Sequestration and Co-Benefits for Drought Resilience in the Sagebrush Steppe and Mixed Grass Prairie Climate Effects on Prescribed Fire Implementation and Efficacy in Northern Mixed-Grass Prairie Alaska's Changing Habitats: A Multi-System Approach for Understanding Climate Impacts in High Latitude Regions