Publications
Publications from USGS science centers throughout the Southeast Region.
Filter Total Items: 9969
Assessing models of arsenic occurrence in drinking water from bedrock aquifers in New Hampshire
Three existing multivariate logistic regression models were assessed using new data to evaluate the capacity of the models to correctly predict the probability of groundwater arsenic concentrations exceeding the threshold values of 1, 5, and 10 micrograms per liter (µg/L) in New Hampshire, USA. A recently released testing dataset includes arsenic concentrations from groundwater samples collected i
Authors
Caroline Andy, Maria Florencia Fahnestock, Melissa Lombard, Laura Hayes, Julie Bryce, Joseph D. Ayotte
Groundwater-level trends in the U.S. glacial aquifer system, 1964-2013
The glacial aquifer system in the United States is a major source of water supply but previous work on historical groundwater trends across the system is lacking. Trends in annual minimum, mean, and maximum groundwater levels for 205 monitoring wells were analyzed across three regions of the system (East, Central, West Central) for four time periods: 1964-2013, 1974-2013, 1984-2013, and 1994-2013.
Authors
Glenn A. Hodgkins, Robert W. Dudley, Martha G. Nielsen, Benjamin Renard, Sharon L. Qi
Simulation of daily streamflow for 12 river basins in western Iowa using the Precipitation-Runoff Modeling System
The U.S. Geological Survey, in cooperation with the Iowa Department of Natural Resources, constructed Precipitation-Runoff Modeling System models to estimate daily streamflow for 12 river basins in western Iowa that drain into the Missouri River. The Precipitation-Runoff Modeling System is a deterministic, distributed-parameter, physical-process-based modeling system developed to evaluate the resp
Authors
Daniel E. Christiansen, Adel E. Haj, John C. Risley
Assessment of an in-channel redistribution technique for large woody debris management in Locust Creek, Linn County, Missouri
The U.S. Geological Survey, in cooperation with the Missouri Department of Conservation and Missouri Department of Natural Resources, completed a study to assess a mechanical redistribution technique used for the management of large woody debris (LWD) jams in Locust Creek within Pershing State Park and Fountain Grove Conservation Area, Linn County, Missouri. Extensive LWD jams were treated from 19
Authors
David C. Heimann
A comparison of four porewater sampling methods for metal mixtures and dissolved organic carbon and the implications for sediment toxicity evaluations
Evaluations of sediment quality conditions are commonly conducted using whole-sediment chemistry analyses but can be enhanced by evaluating multiple lines of evidence, including measures of the bioavailable forms of contaminants. In particular, porewater chemistry data provide information that is directly relevant for interpreting sediment toxicity data. Various methods for sampling porewater for
Authors
Danielle M. Cleveland, William G. Brumbaugh, Donald D. MacDonald
The importance of parameterization when simulating the hydrologic response of vegetative land-cover change
Computer models of hydrologic systems are frequently used to investigate the hydrologic response of land-cover change. If the modeling results are used to inform resource-management decisions, then providing robust estimates of uncertainty in the simulated response is an important consideration. Here we examine the importance of parameterization, a necessarily subjective process, on uncertainty es
Authors
Jeremy T. White, Victoria G. Stengel, Samuel H. Rendon, John Banta
Forecast first: An argument for groundwater modeling in reverse
Numerical groundwater models are important compo-nents of groundwater analyses that are used for makingcritical decisions related to the management of ground-water resources. In this support role, models are oftenconstructed to serve a specific purpose that is to provideinsights, through simulation, related to a specific func-tion of a complex aquifer system that cannot be observeddirectly (Anderson
Authors
Jeremy T. White
Millennial-scale variability in the local radiocarbon reservoir age of south Florida during the Holocene
A growing body of research suggests that the marine environments of south Florida provide a critical link between the tropical and high-latitude Atlantic. Changes in the characteristics of water masses off south Florida may therefore have important implications for our understanding of climatic and oceanographic variability over a broad spatial scale; however, the sources of variability within thi
Authors
Lauren T. Toth, Hai Cheng, R. Lawrence Edwards, Erica Ashe, Julie N. Richey
A revised list of the freshwater mussels (Mollusca: Bivalvia: Unionida) of the United States and Canada
We present a revised list of freshwater mussels (order Unionida, families Margaritiferidae and Unionidae) of the United States and Canada, incorporating changes in nomenclature and systematic taxonomy since publication of the most recent checklist in 1998. We recognize a total of 298 species in 55 genera in the families Margaritiferidae (one genus, five species) and Unionidae (54 genera, 293 speci
Authors
James D. Williams, Arthur E. Bogan, Robert S. Butler, Kevin S. Cummings, Jeffrey T. Garner, John L. Harris, Nathan A. Johnson, G. Thomas Watters
Simulated effects of Lower Floridan aquifer pumping on the Upper Floridan aquifer at Barbour Pointe, Chatham County, Georgia
Steady-state simulations using a revised regional groundwater-flow model based on MODFLOW were run to assess the potential long-term effects on the Upper Floridan aquifer (UFA) of pumping the Lower Floridan aquifer (LFA) at well 36Q398, located at Barbour Pointe in coastal Georgia near Savannah. Simulated pumping of well 36Q398 at a rate of 750 gallons per minute (gal/min; or 1.08 million gallons
Authors
Gregory S. Cherry, John S. Clarke
Revision of the jawfish genus Lonchopisthus with description of a new Atlantic species (Teleostei: Opistognathidae)
Synonymies, diagnoses, descriptions, illustrations, an identification key, and meristic frequency tables are provided for all species of Lonchopisthus. Most of the skeletal anatomy of L. higmani is also illustrated. A new jawfish, Lonchopisthus ancistrus n. sp., is described from the Gulf of Mexico and off Honduras based on 21 specimens 41–89 mm SL. The new species differs from other congeners by
Authors
William F. Smith-Vaniz, Stephen J. Walsh
Watershed Data Management (WDM) database for West Branch DuPage River streamflow simulation, DuPage County, Illinois, January 1, 2007, through September 30, 2013
The U.S. Geological Survey (USGS), in cooperation with the DuPage County Stormwater Management Department, maintains a database of hourly meteorological and hydrologic data for use in a near real-time streamflow simulation system. This system is used in the management and operation of reservoirs and other flood-control structures in the West Branch DuPage River watershed in DuPage County, Illinois
Authors
Maitreyee Bera