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Publications

Publications from USGS science centers throughout the Southeast Region.

Filter Total Items: 10379

On the application of multilevel modeling in environmental and ecological studies On the application of multilevel modeling in environmental and ecological studies

This paper illustrates the advantages of a multilevel/hierarchical approach for predictive modeling, including flexibility of model formulation, explicitly accounting for hierarchical structure in the data, and the ability to predict the outcome of new cases. As a generalization of the classical approach, the multilevel modeling approach explicitly models the hierarchical structure in...
Authors
Song S. Qian, Thomas F. Cuffney, Ibrahim Alameddine, Gerard McMahon, Kenneth H. Reckhow

Analytical models for the groundwater tidal prism and associated benthic water flux Analytical models for the groundwater tidal prism and associated benthic water flux

The groundwater tidal prism is defined as the volume of water that inundates a porous medium, forced by one tidal oscillation in surface water. The pressure gradient that generates the prism acts on the subterranean estuary. Analytical models for the groundwater tidal prism and associated benthic flux are presented. The prism and flux are shown to be directly proportional to porosity...
Authors
Jeffrey N. King, Ashish J. Mehta, Robert G. Dean

A new parameterization for estimating co‐occurrence of interacting species A new parameterization for estimating co‐occurrence of interacting species

Models currently used to estimate patterns of species co‐occurrence while accounting for errors in detection of species can be difficult to fit when the effects of covariates on species occurrence probabilities are included. The source of the estimation problems is the particular parameterization used to specify species co‐occurrence probability. We develop a new parameterization for...
Authors
J. Hardin Waddle, Robert M. Dorazio, Susan C. Walls, Kenneth G. Rice, Jeff Beauchamp, Melinda J. Schuman, Frank J. Mazzotti

The 7Q10 in South Carolina water-quality regulation: Nearly fifty years later The 7Q10 in South Carolina water-quality regulation: Nearly fifty years later

The annual minimum 7-day average streamflow with a 10-year recurrence interval, often referred to as the 7Q10, has a long history of being an important low-flow statistic used in water-quality management in South Carolina as evidenced by its adoption into South Carolina law in 1967. State agencies, such as the South Carolina Department of Health and Environmental Control and the South...
Authors
Toby D. Feaster, Wade M. Cantrell

Inter-nesting habitat-use patterns of loggerhead sea turtles: Enhancing satellite tracking with benthic mapping Inter-nesting habitat-use patterns of loggerhead sea turtles: Enhancing satellite tracking with benthic mapping

The loggerhead sea turtle Caretta caretta faces declining nest numbers and bycatches from commercial longline fishing in the southeastern USA. Understanding spatial and temporal habitat-use patterns of these turtles, especially reproductive females in the neritic zone, is critical for guiding management decisions. To assess marine turtle habitat use within the Dry Tortugas National Park...
Authors
Kristen M. Hart, David G. Zawada, Ikuko Fujisaki, Barbara H. Lidz

A comparison of litter production in young and old baldcypress (Taxodium distichum L.) stands at Caddo Lake, Texas A comparison of litter production in young and old baldcypress (Taxodium distichum L.) stands at Caddo Lake, Texas

Aboveground primary productivity for cypress forests was assessed from measurements of litter production in two age groups and in two hydrological regimes (standing water and free-flowing). Caddo Lake, located in northeast Texas on the Texas-Louisiana border, offered a unique study site since it is dominated by extensive stands composed entirely of Taxodium distichum (L.) Rich,...
Authors
John W. McCoy, Rassa O. Draugelis-Dale, Bobby D. Keeland, Roy Darville

Two-dimensional time dependent hurricane overwash and erosion modeling at Santa Rosa Island Two-dimensional time dependent hurricane overwash and erosion modeling at Santa Rosa Island

A 2DH numerical, model which is capable of computing nearshore circulation and morphodynamics, including dune erosion, breaching and overwash, is used to simulate overwash caused by Hurricane Ivan (2004) on a barrier island. The model is forced using parametric wave and surge time series based on field data and large-scale numerical model results. The model predicted beach face and dune...
Authors
R.T. McCall, J. S. M. Van Theil de Vries, N.G. Plant, A. R. Van Dongeren, J.A. Roelvink, D.M. Thompson, A.J.H.M. Reniers

Low-flow frequency and flow duration of selected South Carolina streams in the Broad River basin through March 2008 Low-flow frequency and flow duration of selected South Carolina streams in the Broad River basin through March 2008

In 2008, the U.S. Geological Survey, in cooperation with the South Carolina Department of Health and Environmental Control, initiated a study to update low-flow statistics at continuous-record streamgaging stations operated by the U.S. Geological Survey in South Carolina. This report presents the low-flow statistics for 23 selected streamgaging stations in the Broad River basin in South...
Authors
Wladmir B. Guimaraes, Toby D. Feaster

Occurrence of organic wastewater-indicator compounds in urban streams of the Atlanta area, Georgia, 2003-2006 Occurrence of organic wastewater-indicator compounds in urban streams of the Atlanta area, Georgia, 2003-2006

Between March 2003 and January 2006, 863 water samples were collected from streams in seven urban watersheds with varying land uses within or near the City of Atlanta, Georgia. Sixty-four sampling sites representing three site types were established in those watersheds. The first type consisted of sites within three watersheds not affected by combined sewer overflows; these were...
Authors
Stephen J. Lawrence, Jacob H. LaFontaine

Southeast Regional Assessment Project for the National Climate Change and Wildlife Science Center, U.S. Geological Survey Southeast Regional Assessment Project for the National Climate Change and Wildlife Science Center, U.S. Geological Survey

The Southeastern United States spans a broad range of physiographic settings and maintains exceptionally high levels of faunal diversity. Unfortunately, many of these ecosystems are increasingly under threat due to rapid human development, and management agencies are increasingly aware of the potential effects that climate change will have on these ecosystems. Natural resource managers...
Authors
Melinda S. Dalton, Sonya A. Jones

Sapflow and water use of freshwater wetland trees exposed to saltwater incursion in a tidally influenced South Carolina watershed Sapflow and water use of freshwater wetland trees exposed to saltwater incursion in a tidally influenced South Carolina watershed

Sea-level rise and anthropogenic activity promote salinity incursion into many tidal freshwater forested wetlands. Interestingly, individual trees can persist for decades after salt impact. To understand why, we documented sapflow (Js), reduction in Js with sapwood depth, and water use (F) of baldcypress (Taxodium distichum (L.) Rich.) trees undergoing exposure to salinity. The mean Js...
Authors
K. W. Krauss, J.A. Duberstein
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