Reports
Science Quality and Integrity
The USGS provides unbiased, objective, and impartial scientific information upon which our audiences, including resource managers, planners, and other entities, rely.
The USGS provides unbiased, objective, and impartial scientific information upon which our audiences, including resource managers, planners, and other entities, rely.
Browse more than 82,000 reports authored by our scientists over the past 100+ year history of the USGS and refine search by topic, location, year, and advanced search.
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Groundwater quality in the Valley and Ridge and Piedmont and Blue Ridge carbonate-rock aquifers, eastern United States Groundwater quality in the Valley and Ridge and Piedmont and Blue Ridge carbonate-rock aquifers, eastern United States
Groundwater provides nearly 50 percent of the Nation’s drinking water. To help protect this vital resource, the U.S. Geological Survey (USGS) National Water-Quality Assessment (NAWQA) Project assesses groundwater quality in aquifers that are important sources of drinking water. The Valley and Ridge and Piedmont and Blue Ridge carbonate-rock aquifers constitute two of the important areas...
Authors
Bruce D. Lindsey, Kenneth Belitz
Identification of Neosho Smallmouth Bass (Micropterus dolomieu velox) stocks for possible introduction into Grand Lake, Oklahoma Identification of Neosho Smallmouth Bass (Micropterus dolomieu velox) stocks for possible introduction into Grand Lake, Oklahoma
Stocking black basses (Micropterus spp.) is a common practice used to increase angling opportunities in impoundments; however, when non-native black basses are introduced they often invade riverine habitats where they threaten the persistence of other fishes, including native black basses. Neosho Smallmouth Bass (M. dolomieu velox) is endemic to portions of the Ozark Highlands and Boston...
Authors
Andrew T. Taylor, James M. Long, Michael R. Schwemm, Michael D. Tringali, Shannon K. Brewer
Integrated water flow model and modflow-farm process: A comparison of theory, approaches, and features of two integrated hydrologic models Integrated water flow model and modflow-farm process: A comparison of theory, approaches, and features of two integrated hydrologic models
Effective modeling of conjunctive use of surface and subsurface water resources requires simulation of land use-based root zone and surface flow processes as well as groundwater flows, streamflows, and their interactions. Recently, two computer models developed for this purpose, the Integrated Water Flow Model (IWFM) from the California Department of Water Resources and the MODFLOW with...
Authors
Emin C. Dogrul, Wolfgang Schmid, Randall T. Hanson, Tariq Kadir, Francis Chung
National Land Cover Database 2001 (NLCD01) National Land Cover Database 2001 (NLCD01)
This 30-meter data set represents land use and land cover for the conterminous United States for the 2001 time period. The data have been arranged into four tiles to facilitate timely display and manipulation within a Geographic Information System (see http://water.usgs.gov/GIS/browse/nlcd01-partition.jpg). The National Land Cover Data Set for 2001 was produced through a cooperative...
Authors
Andrew E. LaMotte
Northeast and Midwest regional species and habitats at greatest risk and most vulnerable to climate impacts Northeast and Midwest regional species and habitats at greatest risk and most vulnerable to climate impacts
The objectives of this Chapter are to describe climate change vulnerability, it’s components, the range of assessment methods being implemented regionally, and examples of training resources and tools. Climate Change Vulnerability Assessments (CCVAs) have already been conducted for numerous Regional Species of Greatest Conservation Need and their dependent 5 habitats across the Northeast...
Authors
Michelle D. Staudinger, Laura Hilberg, Maria Janowiak, C.O. Swanton
Nutrient, organic carbon, and chloride concentrations and loads in selected Long Island Sound tributaries—Four decades of change following the passage of the Federal Clean Water Act Nutrient, organic carbon, and chloride concentrations and loads in selected Long Island Sound tributaries—Four decades of change following the passage of the Federal Clean Water Act
Trends in long-term water-quality and streamflow data from 14 water-quality monitoring sites in Connecticut were evaluated for water years 1974–2013 and 2001–13, coinciding with implementation of the Clean Water Act of 1972 and the Connecticut Nitrogen Credit Exchange program, as part of an assessment of nutrient and chloride concentrations and loads discharged to Long Island Sound. In...
Authors
John R. Mullaney
Populations of concern Populations of concern
Climate change is already causing, and is expected to continue to cause, a range of health impacts that vary across different population groups in the United States. The vulnerability of any given group is a function of its sensitivity to climate change related health risks, its exposure to those risks, and its capacity for responding to or coping with climate variability and change...
Authors
Janet Gamble, John Balbus, Martha Berger, Karen Bouye, Vince Campbell, Karletta Chief, K. Conlon, Allison Crimmins, Barry Flanagan, C. Gonzalez-Maddux, E. Hallisey, S. Hutchins, L. Jantarasami, S. Khoury, M. Kiefer, J. Kolling, K. Lynn, A. Manangan, M. McDonald, R. Morello-Frosch, Margaret Hiza, P. Sheffield, K. Thigpen Tart, J. Watson, K.P. Whyte, A.F. Wolkin
Potentiometric surface and water-level difference maps of selected confined aquifers in Southern Maryland and Maryland’s Eastern Shore, 1975-2015 Potentiometric surface and water-level difference maps of selected confined aquifers in Southern Maryland and Maryland’s Eastern Shore, 1975-2015
Key Results This report presents potentiometric-surface maps of the Aquia and Magothy aquifers and the Upper Patapsco, Lower Patapsco, and Patuxent aquifer systems using water levels measured during September 2015. Water-level difference maps are also presented for these aquifers. The water-level differences in the Aquia aquifer are shown using groundwater-level data from 1982 and 2015...
Authors
Stephen E. Curtin, Andrew W. Staley, David C. Andreasen
Primary production in the Sacramento-San Joaquin Delta: A science strategy to quantify change and identify future potential Primary production in the Sacramento-San Joaquin Delta: A science strategy to quantify change and identify future potential
No abstract available.
Authors
April Robinson, Amy Richey, James E. Cloern, Katharyn E. Boyer, Jon Burau, Elizabeth A. Canuel, John F. DeGeorge, Judith Z. Drexler, E. R. Howe, Ronald Kneib, Anke Mueller-Solger, James L. Pinckney, Robert J. Naiman, David H. Schoellhamer, Charles A. Simenstad
Prioritizing landscapes for longleaf pine conservation Prioritizing landscapes for longleaf pine conservation
We developed a spatially explicit model and map, as a decision support tool (DST), to aid conservation agencies creating or maintaining open pine ecosystems. The tool identified areas that are likely to provide the greatest benefit to focal bird populations based on a comprehensive landscape analysis. We used NLCD 2011, SSURGO, and SEGAP data to map the density of desired resources for...
Authors
J. Barry Grand, Kevin J. Kleiner
Proceedings of the 2015 international summit on fibropapillomatosis: Global status, trends, and population impacts Proceedings of the 2015 international summit on fibropapillomatosis: Global status, trends, and population impacts
The 2015 International Summit on Fibropapillomatosis (FP) was convened in Honolulu, Hawaii June 11-14, 2015. Scientists from around the world were invited to present results from sea turtle monitoring and research programs as they relate to the global status, trends, and population impacts of FP on green turtles. The participants engaged in discussions that resulted in the following...
Authors
Stacy A. Hargrove, Thierry M. Work, Shandell Brunson, Allen M. Foley, George H. Balazs
Regional water table (2014) in the Mojave River and Morongo Groundwater Basins, southwestern Mojave Desert, California Regional water table (2014) in the Mojave River and Morongo Groundwater Basins, southwestern Mojave Desert, California
Data for static water-levels measured in about 610 wells during March-April 2014 by the U.S. Geological Survey (USGS), the Mojave Water Agency (MWA), and other local water districts were compiled to construct a regional water-table map. This map shows the elevation of the water table and general direction of groundwater movement in and around the Mojave River and Morongo groundwater...
Authors
Nick F. Teague, Meghan C. Dick, Sally F. House, Dennis A. Clark