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Environmental Issues

Filter Total Items: 19

Markov decision processes in non-autonomous socio-ecological systems

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 syste
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Markov decision processes in non-autonomous socio-ecological systems

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 syste
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Using a multi-scale approach to synthesize measurements and models of C4 photosynthesis

Plants convert carbon dioxide into sugars for food during photosynthesis, and this provides food for all animal life. However, photosynthesis is inhibited when a plant’s enzymes use oxygen instead of carbon dioxide. To avoid this use of oxygen, some plants developed a photosynthetic adaptation – called C4 photosynthesis – to concentrate carbon dioxide around the enzymes. While less than 5% of plan
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Using a multi-scale approach to synthesize measurements and models of C4 photosynthesis

Plants convert carbon dioxide into sugars for food during photosynthesis, and this provides food for all animal life. However, photosynthesis is inhibited when a plant’s enzymes use oxygen instead of carbon dioxide. To avoid this use of oxygen, some plants developed a photosynthetic adaptation – called C4 photosynthesis – to concentrate carbon dioxide around the enzymes. While less than 5% of plan
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Ecological Forecasting Workshop

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 f
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Ecological Forecasting Workshop

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 f
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Novel multi‐scale synthesis of nitrogen fixation rates and drivers across the terrestrial biosphere

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
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Novel multi‐scale synthesis of nitrogen fixation rates and drivers across the terrestrial biosphere

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
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A global synthesis of land-surface fluxes under natural and human-altered watersheds using the Budyko framework

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
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A global synthesis of land-surface fluxes under natural and human-altered watersheds using the Budyko framework

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
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Linking environmental and public health data to evaluate health effects of arsenic exposure from domestic and public supply wells

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 dri
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Linking environmental and public health data to evaluate health effects of arsenic exposure from domestic and public supply wells

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 dri
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Global Evaluation of the Impacts of Storms on freshwater Habitat and Structure of phytoplankton Assemblages (GEISHA)

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 foo
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Global Evaluation of the Impacts of Storms on freshwater Habitat and Structure of phytoplankton Assemblages (GEISHA)

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 foo
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Local-scale ecosystem resilience amid global-scale ocean change: the coral reef example

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 deterio
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Local-scale ecosystem resilience amid global-scale ocean change: the coral reef example

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 deterio
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Dam removal: synthesis of ecological and physical responses

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 b
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Dam removal: synthesis of ecological and physical responses

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 b
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Forecasting forest response to N deposition: integrating data from individual plant responses to soil chemistry with a continental-scale gradient analysis

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 inte
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Forecasting forest response to N deposition: integrating data from individual plant responses to soil chemistry with a continental-scale gradient analysis

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 inte
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Integrating modeling and empirical approaches to improve predictions of tropical forest responses to global warming

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 bio
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Integrating modeling and empirical approaches to improve predictions of tropical forest responses to global warming

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 bio
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Potential Impacts of Prospective Climate Change on Groundwater Recharge in the Western United States

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
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Potential Impacts of Prospective Climate Change on Groundwater Recharge in the Western United States

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
Learn More