A5067769587- Soil and Water Nutrient Dynamics
- Hydrology and Watershed Management Studies
- Water Quality and Resources Studies
- Fish Ecology and Management Studies
- Groundwater and Isotope Geochemistry
- Soil erosion and sediment transport
- Hydrology and Sediment Transport Processes
- Water Quality and Pollution Assessment
- Soil Geostatistics and Mapping
- Soil Moisture and Remote Sensing
- Methane Hydrates and Related Phenomena
- Geophysics and Gravity Measurements
- Marine and fisheries research
- Atmospheric and Environmental Gas Dynamics
- Climate change and permafrost
- Historical Geography and Cartography
- Radioactive contamination and transfer
- Groundwater flow and contamination studies
- Climate variability and models
- Cryospheric studies and observations
- Oceanographic and Atmospheric Processes
- Geographic Information Systems Studies
- Geological Modeling and Analysis
- Advanced Computational Techniques and Applications
- Isotope Analysis in Ecology
United States Geological Survey
1997-2023
Fundación Ramón Domínguez
2023
Universidade de Santiago de Compostela
2023
NSF National Center for Atmospheric Research
2023
Colorado State University
2023
University of Vienna
2020
Seasonal hypoxia in the northern Gulf of Mexico has been linked to increased nitrogen fluxes from Mississippi and Atchafalaya River Basins, though recent evidence shows that phosphorus also influences productivity Gulf. We developed a spatially explicit structurally detailed SPARROW water-quality model reveals important differences sources transport processes control (N) (P) delivery Our simulations indicate agricultural watersheds contribute more than 70% delivered N P. However, corn...
Abstract A unique, high-resolution, hydroclimate reanalysis, 40-plus-year (October 1979–September 2021), 4 km (named as CONUS404), has been created using the Weather Research and Forecasting Model by dynamically downscaling of fifth-generation European Centre for Medium-Range Forecasts (ECMWF) atmospheric reanalysis global climate dataset (ERA5) over conterminous United States. The paper describes approach generating dataset, provides an initial evaluation, including biases, indicates how...
Abstract This review aims to synthesize the current knowledge of sediment dynamics using insights from long‐term research conducted in watershed draining Chesapeake Bay, largest estuary U.S., inform management actions restore and its watershed. The are typical many impaired watersheds estuaries around world, this synthesis is intended be relevant transferable other sediment‐impaired systems. watershed's sources, transport, delivery, impacts discussed with implications for effectively...
Spatially Referenced Regression on Watershed Attributes (SPARROW) was used to provide empirical estimates of the sources, fate, and transport total nitrogen (TN) phosphorus (TP) in Chesapeake Bay watershed, mean annual TN TP flux bay each 80,579 nontidal tributary stream reaches. Restoration efforts recent decades have been insufficient meet established standards for water quality ecological conditions Bay. The watershed includes 166,000 square kilometers mixed land uses, multiple nutrient...
Brakebill, J.W., D.M. Wolock, and S.E. Terziotti, 2011. Digital Hydrologic Networks Supporting Applications Related to Spatially Referenced Regression Modeling. Journal of the American Water Resources Association (JAWRA) 47(5):916-932. DOI: 10.1111/j.1752-1688.2011.00578.x Abstract: hydrologic networks depicting surface-water pathways their associated drainage catchments provide a key component analysis modeling. Collectively, they form common spatial units that can be used frame...
Brakebill, John W., Scott W. Ator, and Gregory E. Schwarz, 2010. Sources of Suspended‐Sediment Flux in Streams the Chesapeake Bay Watershed: A Regional Application SPARROW Model. Journal American Water Resources Association (JAWRA) 46(4): 757‐776. DOI: 10.1111/j.1752‐1688.2010.00450.x Abstract: We describe sources transport fluvial suspended sediment nontidal streams watershed vicinity. applied SPAtially Referenced Regressions on Watershed attributes, which spatially correlates estimated...
ABSTRACT: A regional assessment of water quality in small streams was conducted within four areas distinct physiography and lithology the upper Potomac River Basin. The is a major tributary to Chesapeake Bay, this study provides new insight on relationships between nutrient concentrations watershed characteristics river basin. Nutrient were compared land‐use data including categories for agriculture (cropland pasture), urban areas, forests. Among agricultural draining intense row cropping...
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) support national regional-scale surface water-quality modeling. Alexander others (1999) developed ERF1, which assessed hydrologic integrity of reach traces calculated mean water time-of-travel in river reaches reservoirs. ERF1_2 serves as foundation for SPARROW (Spatially Referenced Regressions...
Chesapeake Bay restoration efforts are focused on improving water quality, living resources, and ecological habitats by 2010. One aspect of the water-quality is refinement strategies designed to implement nutrient-reduction practices within watershed. These being refined implemented resource managers Program (CBP), a partnership comprised various Federal, State, local agencies that includes jurisdictions Delaware, Maryland, New York, Pennsylvania, Virginia, West District Columbia. The U.S....
U.S. Environmental Protection Agency's River Reach File 1 (RF1) to ensure the hydrologic integrity of digital reach traces and quantify mean water time travel in river reaches reservoirs [see USEPA (1996) for a description original RF1].
First posted March 9, 2020 For additional information, contact: NAWQA Science TeamNational Water Quality ProgramU.S. Geological Survey12201 Sunrise Valley Drive, MS 413Reston, VA 20191-0002 The National Hydrography Dataset Plus, Version 2.1 (NHDPlusV2.1) is an attribute-rich digital stream network for the conterminous United States, serving as a foundational infrastructure reporting hydrologic information at both regional and national scales. SPAtially Referenced Regressions On Watershed...
The purpose of this report is to present a synthesis the USGS Chesapeake Bay science related 2001-06 goals and provide implications for environmental management. provides findings that address needs Program (CBP) restoration includes summaries 1. land-use change; 2. water quality in watershed, including nutrients, sediment, contaminants; 3. long-term changes climate estuarine quality; 4. estuary habitats, focusing on submerged aquatic vegetation (SAV) tidal wetlands; 5. factors affecting...
First posted February 26, 2019 For additional information, contact: Director, Upper Midwest Water Science CenterU.S. Geological Survey8505 Research WayMiddleton, Wisconsin 53562 Nutrient inputs from commercial agricultural fertilizer, particularly nitrogen and phosphorus, are important factors contributing to the degradation of surface-water quality alteration aquatic ecosystems. Despite this importance, information about application fertilizer land is not available in a consistent manner...
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 Chesapeake Bay region. These regressions relate streamwater loads to nutrient sources factors that affect transport these nutrients throughout watershed. A digital segmented network based on watershed boundaries serves primary foundation spatially referencing total nitrogen phosphorus source land-surface characteristic within...
The Chesapeake Bay is the Nation's largest estuary and historically supported one of most productive fisheries in world. In addition to supporting aquatic communities wildlife, bay's watershed serves economic recreational needs 15 million people. fertile soils support significant agricultural production. Unfortunately, commercial, economic, value bay its has been degraded by poor water quality, loss habitat, overharvesting living resources. Since early 1980's, Program, which a partnership...
A digital hydrologic network was developed to support SPAtially Referenced Regression on Watershed attributes (SPARROW) models within selected regions of the United States. These correspond with U.S. Geological Survey's National Water Quality Assessment (NAWQA) Program Major River Basin (MRB) study units 2, 3, 4, 5, and 7 (Preston others, 2009). MRB2, covers South Atlantic-Gulf Tennessee basins. MRB3, Great Lakes, Ohio, Upper Mississippi, Souris-Red-Rainy MRB4, Missouri MRB5, Lower...