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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...
Description of WorkThe Great Lakes Restoration Initiative (GLRI) was established to accelerate ecosystem restoration in the Great Lakes by confronting the most serious threats to the region, such as nonpoint source pollution, toxic sediments, and invasive species. Four Priority Watersheds have been targeted by the Regional Working Group's Phosphorus Reduction Work Group (Fox/Green Bay, Saginaw, Maumee, and Genesee) and are characterized by having a high density of agricultural land use and have ecosystem impairments that have been clearly identified. Monitoring is being conducted at the sub-watershed, edge-of-field, and subsurface-tile scale where monitoring locations are targeted to those areas within each watershed...
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PROBLEM There are more than 60 organizations and agencies collecting water-quality data on Long Island. The types of database management that are used to store and archive regulatory and non-regulatory data vary from paper forms to spreadsheets to State and Federal databases, and there is minimal communication between these systems. As a result, those interested in analyzing data may be unaware of what data exist and how those data can be obtained without a Freedom of Information Law request. A unified data sharing system that provides multiple levels of sensitive and non-sensitive data storage and dissemination is needed. This system should link the various databases and interact through web services to provide...
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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...
The tundra biome is the dominant terrestrial ecosystem of the circumpolar north, and its fate in a rapidly changing climate is of high scientific and socioeconomic concern. One of those concerns is that the majority of caribou herds throughout the circumpolar north are declining, perhaps as a result of climate change. The principal objective of this research is to reveal the connections between soil nutrient cycling, forage quality and caribou habitat selection. This framework is underpinned by the concept that tundra ecosystem productivity is ultimately driven by the thermodynamics of the system induced by climate. In winter, soil microbial processes drive N mineralization and thus N available for plant growth...
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Description of Work The Great Lakes Restoration Initiative (GLRI) was established to accelerate ecosystem restoration in the Great Lakes by confronting the most serious threats to the region, such as nonpoint source pollution, toxic sediments, and invasive species. Three Priority Watersheds have been targeted by the Regional Working Group's Phosphorus Reduction Work Group (Fox/Green Bay, Saginaw, and Maumee) and are characterized by having a high density of agricultural land use and have ecosystem impairments that have been clearly identified. Within the Maumee River Priority Watersheds, monitoring is being conducted at the sub-watershed, edge-of-field, and subsurface-tile scale. The edge-of-field and subsurface-tile...
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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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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,...