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Reports

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.

Filter Total Items: 84803

Gap analysis: A proposed methodology to describe and map historical and contemporary populations and habitats Gap analysis: A proposed methodology to describe and map historical and contemporary populations and habitats

This is a methodology paper that describes an approach for modeling and mapping historical and contemporary spawning areas for coregonine fishes in the Laurentian Great Lakes. Coregonines are a family of native whitefishes and ciscoes that are now greatly reduced or extirpated, but once served important roles for both the food web and society. This method can illustrate where habitats...
Authors
Cory Brant, Karen M Alofs, Chris Castiglione, Susan E. Doka, Alexander T. Duncan, Dave Fielder, Matthew Herbert, Arunas Liskauskus, Edward S. Rutherford, Jason Smith, Ralph W. Tingley, Ted Treska, Ted Turschak, Cindy Chu, Peter C. Esselman

Prediction of the probability of elevated nitrate concentrations at groundwater depths used for drinking-water supply in the Puget Sound basin, Washington, 2004–19 Prediction of the probability of elevated nitrate concentrations at groundwater depths used for drinking-water supply in the Puget Sound basin, Washington, 2004–19

The Puget Sound basin encompasses the 13,700-square-mile area that drains to the Puget Sound and the adjacent marine waters of Washington State. Well more than 4 million people live within the basin, with numbers continuing to increase, who rely on the basin’s natural resources including groundwater. The Puget Sound Partnership was created by a Washington State statute to implement a...
Authors
Robert W. Black, Elise E. Wright, Valerie A.L. Bright, Alexander O. Headman

Changes in phosphorus and suspended solids loading in the Fox River, northeastern Wisconsin, 1989–2021 Changes in phosphorus and suspended solids loading in the Fox River, northeastern Wisconsin, 1989–2021

The entire Lower Fox River and inner bay of Green Bay, in northeastern Wisconsin, have been listed as impaired by the Wisconsin Department of Natural Resources (WDNR) for low dissolved oxygen and degraded habitat, with total phosphorus (TP) and total suspended solids (TSS) concentrations listed as the likely causes of these impairments. To restore the Fox River and Green Bay, total...
Authors
Dale M. Robertson, Matthew W. Diebel, Sarah L. Bartlett, Kevin J. Fermanich

Creating an updated vegetation map for Big Oaks National Wildlife Refuge: Final report Creating an updated vegetation map for Big Oaks National Wildlife Refuge: Final report

Although Big Oaks NWR encompasses much diversity in wildlife species, an up-to-date, detailed, and comprehensive map showing vegetation types was lacking. The creation of an updated vegetation map for Big Oaks NWR was approved in early 2019. Digital aerial imagery was collected on November 1, 2019 at a resolution of 0.15 meter per pixel using four spectral bands: red, green, blue, and...
Authors
Erin E. Hoy

Automated construction of Streamflow-Routing networks for MODFLOW—Application in the Mississippi Embayment region Automated construction of Streamflow-Routing networks for MODFLOW—Application in the Mississippi Embayment region

In humid regions with dense stream networks, surface water exerts a fundamental control on the water levels and flow directions of shallow groundwater. Understanding interactions between groundwater and surface water is critical for managing groundwater resources and groundwater-dependent ecosystems. Representing streams in groundwater models has historically been arduous and error prone...
Authors
Andrew T. Leaf

Simulating groundwater flow in the Mississippi Alluvial Plain with a focus on the Mississippi Delta Simulating groundwater flow in the Mississippi Alluvial Plain with a focus on the Mississippi Delta

The Mississippi Alluvial Plain has become one of the most important agricultural regions in the United States but relies heavily on groundwater for irrigation. On average, more than 12 billion gallons are withdrawn daily from the Mississippi River Valley alluvial aquifer. Declining groundwater levels, especially in the Delta region of northwest Mississippi and the Cache and Grand Prairie...
Authors
Andrew T. Leaf, Leslie L. Duncan, Connor J. Haugh, Randall J. Hunt, James R. Rigby
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