John Brakebill (Former Employee)
Science and Products
Filter Total Items: 30
Differences in phosphorus and nitrogen delivery to the Gulf of Mexico from the Mississippi River Basin Differences in phosphorus and nitrogen delivery to the Gulf of Mexico from the Mississippi River Basin
Seasonal hypoxia in the northern Gulf of Mexico has been linked to increased nitrogen fluxes from the Mississippi and Atchafalaya River Basins, though recent evidence shows that phosphorus also influences productivity in the Gulf. We developed a spatially explicit and structurally detailed SPARROW water-quality model that reveals important differences in the sources and transport...
Authors
R. B. Alexander, R. A. Smith, G. E. Schwarz, E.W. Boyer, J.V. Nolan, J. W. Brakebill
Synthesis of U.S. Geological Survey science for the Chesapeake Bay ecosystem and implications for environmental management Synthesis of U.S. Geological Survey science for the Chesapeake Bay ecosystem and implications for environmental management
The purpose of this report is to present a synthesis of the USGS Chesapeake Bay science related to the 2001-06 goals and provide implications for environmental management. The report provides USGS findings that address the science needs of the Chesapeake Bay Program (CBP) restoration goals and includes summaries of 1. land-use change; 2. water quality in the watershed, including...
Authors
Scott W. Ator, Vicki S. Blazer, John W. Brakebill, Donald R. Cahoon, Peter R. Claggett, Thomas M. Cronin, Judith M. Denver, Christine L. Densmore, Allen C. Gellis, Cliff R. Hupp, Jurate M. Landwehr, Michael J. Langland, Christopher A. Ottinger, Milan J. Pavich, Matthew C. Perry, Scott W. Phillips, Stephen D. Preston, Jeff P. Raffensperger, Barnett A. Rattner, Nancy B. Rybicki, Debra A. Willard
Proceedings of the U.S. Geological Survey Sixth Biennial Geographic Information Science Workshop, Denver, Colorado, April 24-28, 2006 Proceedings of the U.S. Geological Survey Sixth Biennial Geographic Information Science Workshop, Denver, Colorado, April 24-28, 2006
The U.S. Geological Survey's (USGS) Sixth Biennial Geographic Information Science Workshop April 24 - 28, 2006, at the Denver Federal Center in Denver, Colorado, provides a unique opportunity for multi-disciplinary Geographic Information Systems (GIS) and associated scientific professionals to share, learn, present, and discuss a wide variety of geospatial-related topics. Information is...
Authors
John W. Brakebill, Jennifer B. Sieverling, Peter G. Chirico
Digital data used to relate nutrient inputs to water quality in the Chesapeake Bay watershed, version 3.0 Digital data used to relate nutrient inputs to water quality in the Chesapeake Bay watershed, version 3.0
Chesapeake Bay restoration efforts are focused on improving water quality, living resources, and ecological habitats by 2010. One aspect of the water-quality restoration is the refinement of strategies designed to implement nutrient-reduction practices within the Bay watershed. These strategies are being refined and implemented by resource managers of the Chesapeake Bay Program (CBP), a
Authors
John W. Brakebill, Stephen D. Preston
A hydrologic network supporting spatially referenced regression modeling in the Chesapeake Bay watershed A hydrologic network supporting spatially referenced regression modeling in the Chesapeake Bay watershed
The U.S. Geological Survey has developed a methodology for statistically relating nutrient sources and land-surface characteristics to nutrient loads of streams. The methodology is referred to as SPAtially Referenced Regressions On Watershed attributes (SPARROW), and relates measured stream nutrient loads to nutrient sources using nonlinear statistical regression models. A spatially...
Authors
J. W. Brakebill, S. D. Preston
ERF1_2 -- Enhanced River Reach File 2.0 ERF1_2 -- Enhanced River Reach File 2.0
The digital segmented network based on watershed boundaries, ERF1_2, includes enhancements to the U.S. Environmental Protection Agency's River Reach File 1 (RF1) (USEPA, 1996; DeWald and others, 1985) to support national and regional-scale surface water-quality modeling. Alexander and others (1999) developed ERF1, which assessed the hydrologic integrity of the digital reach traces and...
Authors
Jacqueline V. Nolan, John W. Brakebill, Richard B. Alexander, Gregory E. Schwarz
The U.S. Geological Survey and the Chesapeake Bay – The role of science in environmental restoration The U.S. Geological Survey and the Chesapeake Bay – The role of science in environmental restoration
The Chesapeake Bay is the Nation's largest estuary and historically supported one of the most productive fisheries in the world. In addition to supporting aquatic communities and wildlife, the bay's watershed serves the economic and recreational needs of 15 million people. The fertile soils of the watershed support significant agricultural production. Unfortunately, the commercial...
Authors
Roger A. Barlow, John W. Brakebill, John F. Bratton, Vicki S. Blazer, John Karl Bohlke, Owen P. Bricker, Steve M. Colman, Thomas M. Cronin, Cliff R. Hupp, Janet R. Keough, Jurate M. Landwehr, Michael J. Langland, Wayne L. Newell, Matthew Perry, Scott W. Phillips, Steve D. Preston, Nancy B. Rybicki, Nancy S. Simon, Debra A. Willard
By
Ecosystems Mission Area, Water Resources Mission Area, Climate Adaptation Science Centers, Chesapeake Bay Activities, Eastern Ecological Science Center, Florence Bascom Geoscience Center, Maryland-Delaware-D.C. Water Science Center, Pennsylvania Water Science Center, Woods Hole Coastal and Marine Science Center
Digital data used to relate nutrient input to water quality in the Chesapeake Bay watershed Digital data used to relate nutrient input to water quality in the Chesapeake Bay watershed
Digital data sets compiled by the U.S. Geological Survey were used as input for a collection of Spatially Referenced Regressions On Watershed (SPARROW) attributes for the Chesapeake Bay region including parts of Delaware, Maryland, New York, Pennsylvania, Virginia, West Virginia, and the District of Columbia. These regressions use a nonlinear statistical approach to relate nutrient...
Authors
John W. Brakebill, Stephen D. Preston, Sarah K. Martucci
Hydrogeomorphic Regions of the Chesapeake Bay Watershed: HGMR Hydrogeomorphic Regions of the Chesapeake Bay Watershed: HGMR
Generalized lithology (rock type) and physiography based on geologic formations were used to characterize hydrgeomorphic regions (HGMR) within the Chesapeake Bay watershed. These HGMRs were used in conjunction with existing data to assess the significance of ground-water discharge as a source of nitrate load to nontidal streams in the Chesapeake Bay watershed (Bachman and others, 1998)...
Authors
John W. Brakebill, S.K. Kelley
Digital data used to relate nutrient inputs to water quality in the Chesapeake Bay watershed Digital data used to relate nutrient inputs to water quality in the Chesapeake Bay watershed
Digital data sets were compiled by the U. S. Geological Survey (USGS) and used as input for a collection of Spatially Referenced Regressions On Watershed attributes for the Chesapeake Bay region. These regressions relate streamwater loads to nutrient sources and the factors that affect the transport of these nutrients throughout the watershed. A digital segmented network based on...
Authors
John W. Brakebill, Stephen D. Preston
ERF1 -- Enhanced River Reach File 1.2 ERF1 -- Enhanced River Reach File 1.2
U.S. Environmental Protection Agency's River Reach File 1 (RF1) to ensure the hydrologic integrity of the digital reach traces and to quantify the mean water time of travel in river reaches and reservoirs [see USEPA (1996) for a description of the original RF1].
Authors
Richard B. Alexander, John W. Brakebill, Robert E. Brew, Richard A. Smith
Application of spatially referenced regression modeling for the evaluation of total nitrogen loading in the Chesapeake Bay watershed Application of spatially referenced regression modeling for the evaluation of total nitrogen loading in the Chesapeake Bay watershed
The reduction of stream nutrient loads is an important part of current efforts to improve water quality in the Chesapeake Bay. To design programs that will effectively reduce stream nutrient loading, resource managers need spatially detailed information that describes the location of nutrient sources and the watershed factors that affect delivery of nutrients to the Bay. To address this...
Authors
Stephen D. Preston, John W. Brakebill
Science and Products
Filter Total Items: 30
Differences in phosphorus and nitrogen delivery to the Gulf of Mexico from the Mississippi River Basin Differences in phosphorus and nitrogen delivery to the Gulf of Mexico from the Mississippi River Basin
Seasonal hypoxia in the northern Gulf of Mexico has been linked to increased nitrogen fluxes from the Mississippi and Atchafalaya River Basins, though recent evidence shows that phosphorus also influences productivity in the Gulf. We developed a spatially explicit and structurally detailed SPARROW water-quality model that reveals important differences in the sources and transport...
Authors
R. B. Alexander, R. A. Smith, G. E. Schwarz, E.W. Boyer, J.V. Nolan, J. W. Brakebill
Synthesis of U.S. Geological Survey science for the Chesapeake Bay ecosystem and implications for environmental management Synthesis of U.S. Geological Survey science for the Chesapeake Bay ecosystem and implications for environmental management
The purpose of this report is to present a synthesis of the USGS Chesapeake Bay science related to the 2001-06 goals and provide implications for environmental management. The report provides USGS findings that address the science needs of the Chesapeake Bay Program (CBP) restoration goals and includes summaries of 1. land-use change; 2. water quality in the watershed, including...
Authors
Scott W. Ator, Vicki S. Blazer, John W. Brakebill, Donald R. Cahoon, Peter R. Claggett, Thomas M. Cronin, Judith M. Denver, Christine L. Densmore, Allen C. Gellis, Cliff R. Hupp, Jurate M. Landwehr, Michael J. Langland, Christopher A. Ottinger, Milan J. Pavich, Matthew C. Perry, Scott W. Phillips, Stephen D. Preston, Jeff P. Raffensperger, Barnett A. Rattner, Nancy B. Rybicki, Debra A. Willard
Proceedings of the U.S. Geological Survey Sixth Biennial Geographic Information Science Workshop, Denver, Colorado, April 24-28, 2006 Proceedings of the U.S. Geological Survey Sixth Biennial Geographic Information Science Workshop, Denver, Colorado, April 24-28, 2006
The U.S. Geological Survey's (USGS) Sixth Biennial Geographic Information Science Workshop April 24 - 28, 2006, at the Denver Federal Center in Denver, Colorado, provides a unique opportunity for multi-disciplinary Geographic Information Systems (GIS) and associated scientific professionals to share, learn, present, and discuss a wide variety of geospatial-related topics. Information is...
Authors
John W. Brakebill, Jennifer B. Sieverling, Peter G. Chirico
Digital data used to relate nutrient inputs to water quality in the Chesapeake Bay watershed, version 3.0 Digital data used to relate nutrient inputs to water quality in the Chesapeake Bay watershed, version 3.0
Chesapeake Bay restoration efforts are focused on improving water quality, living resources, and ecological habitats by 2010. One aspect of the water-quality restoration is the refinement of strategies designed to implement nutrient-reduction practices within the Bay watershed. These strategies are being refined and implemented by resource managers of the Chesapeake Bay Program (CBP), a
Authors
John W. Brakebill, Stephen D. Preston
A hydrologic network supporting spatially referenced regression modeling in the Chesapeake Bay watershed A hydrologic network supporting spatially referenced regression modeling in the Chesapeake Bay watershed
The U.S. Geological Survey has developed a methodology for statistically relating nutrient sources and land-surface characteristics to nutrient loads of streams. The methodology is referred to as SPAtially Referenced Regressions On Watershed attributes (SPARROW), and relates measured stream nutrient loads to nutrient sources using nonlinear statistical regression models. A spatially...
Authors
J. W. Brakebill, S. D. Preston
ERF1_2 -- Enhanced River Reach File 2.0 ERF1_2 -- Enhanced River Reach File 2.0
The digital segmented network based on watershed boundaries, ERF1_2, includes enhancements to the U.S. Environmental Protection Agency's River Reach File 1 (RF1) (USEPA, 1996; DeWald and others, 1985) to support national and regional-scale surface water-quality modeling. Alexander and others (1999) developed ERF1, which assessed the hydrologic integrity of the digital reach traces and...
Authors
Jacqueline V. Nolan, John W. Brakebill, Richard B. Alexander, Gregory E. Schwarz
The U.S. Geological Survey and the Chesapeake Bay – The role of science in environmental restoration The U.S. Geological Survey and the Chesapeake Bay – The role of science in environmental restoration
The Chesapeake Bay is the Nation's largest estuary and historically supported one of the most productive fisheries in the world. In addition to supporting aquatic communities and wildlife, the bay's watershed serves the economic and recreational needs of 15 million people. The fertile soils of the watershed support significant agricultural production. Unfortunately, the commercial...
Authors
Roger A. Barlow, John W. Brakebill, John F. Bratton, Vicki S. Blazer, John Karl Bohlke, Owen P. Bricker, Steve M. Colman, Thomas M. Cronin, Cliff R. Hupp, Janet R. Keough, Jurate M. Landwehr, Michael J. Langland, Wayne L. Newell, Matthew Perry, Scott W. Phillips, Steve D. Preston, Nancy B. Rybicki, Nancy S. Simon, Debra A. Willard
By
Ecosystems Mission Area, Water Resources Mission Area, Climate Adaptation Science Centers, Chesapeake Bay Activities, Eastern Ecological Science Center, Florence Bascom Geoscience Center, Maryland-Delaware-D.C. Water Science Center, Pennsylvania Water Science Center, Woods Hole Coastal and Marine Science Center
Digital data used to relate nutrient input to water quality in the Chesapeake Bay watershed Digital data used to relate nutrient input to water quality in the Chesapeake Bay watershed
Digital data sets compiled by the U.S. Geological Survey were used as input for a collection of Spatially Referenced Regressions On Watershed (SPARROW) attributes for the Chesapeake Bay region including parts of Delaware, Maryland, New York, Pennsylvania, Virginia, West Virginia, and the District of Columbia. These regressions use a nonlinear statistical approach to relate nutrient...
Authors
John W. Brakebill, Stephen D. Preston, Sarah K. Martucci
Hydrogeomorphic Regions of the Chesapeake Bay Watershed: HGMR Hydrogeomorphic Regions of the Chesapeake Bay Watershed: HGMR
Generalized lithology (rock type) and physiography based on geologic formations were used to characterize hydrgeomorphic regions (HGMR) within the Chesapeake Bay watershed. These HGMRs were used in conjunction with existing data to assess the significance of ground-water discharge as a source of nitrate load to nontidal streams in the Chesapeake Bay watershed (Bachman and others, 1998)...
Authors
John W. Brakebill, S.K. Kelley
Digital data used to relate nutrient inputs to water quality in the Chesapeake Bay watershed Digital data used to relate nutrient inputs to water quality in the Chesapeake Bay watershed
Digital data sets were compiled by the U. S. Geological Survey (USGS) and used as input for a collection of Spatially Referenced Regressions On Watershed attributes for the Chesapeake Bay region. These regressions relate streamwater loads to nutrient sources and the factors that affect the transport of these nutrients throughout the watershed. A digital segmented network based on...
Authors
John W. Brakebill, Stephen D. Preston
ERF1 -- Enhanced River Reach File 1.2 ERF1 -- Enhanced River Reach File 1.2
U.S. Environmental Protection Agency's River Reach File 1 (RF1) to ensure the hydrologic integrity of the digital reach traces and to quantify the mean water time of travel in river reaches and reservoirs [see USEPA (1996) for a description of the original RF1].
Authors
Richard B. Alexander, John W. Brakebill, Robert E. Brew, Richard A. Smith
Application of spatially referenced regression modeling for the evaluation of total nitrogen loading in the Chesapeake Bay watershed Application of spatially referenced regression modeling for the evaluation of total nitrogen loading in the Chesapeake Bay watershed
The reduction of stream nutrient loads is an important part of current efforts to improve water quality in the Chesapeake Bay. To design programs that will effectively reduce stream nutrient loading, resource managers need spatially detailed information that describes the location of nutrient sources and the watershed factors that affect delivery of nutrients to the Bay. To address this...
Authors
Stephen D. Preston, John W. Brakebill