Publications

Prolonged drought, allocation of surface-water flow, and increased demands on ground-water supplies resulting from population growth are focuses for the need to evaluate ground-water resources in the Blue Ridge and Piedmont Provinces of North Carolina. Urbanization and certain aspects of agricultural production also have caused increased concerns about protecting the quality of ground...

Some fish in the Donna Canal contain PCBs at levels that might pose a risk to human health if the fish are eaten. Early attempts to locate the source of PCBs in the canal were unsuccessful. An innovative method of sampling and analyzing suspended sediment helped scientists detect PCBs in suspended sediment and narrowed the probable PCB source area(s) from the entire 11-kilometer canal to...

This report presents ground-water-quality data from the surficial, Upper Floridan, Claiborne, Clayton, and Upper Cretaceous aquifers in the Albany and surrounding areas of southwest Georgia. Water-quality data from about 186 wells in Baker, Calhoun, Dougherty, Lee, Mitchell, Terrell, and Worth Counties are presented for the period from 1951 through 1999. The data include field water...

Five streamflow gain-loss measurement surveys were made along lower San Pedro Creek and the San Antonio River from Mitchell Street to South Loop 410 east of Kelly Air Force Base in San Antonio, Texas, during May–October 1999. All of the measurements were made during dry periods, when stormwater runoff was not occurring and effects of possible bank storage were minimized. San Pedro Creek...

This report presents data on the status of fish, macroinvertebrates, and stream habitat collected from 10 sites in the lower (estuarine) parts of Armand and Dickinson Bayous near Galveston Bay, Texas, during summer 2000 and winter 2001. The total number of individual fish caught at the five Armand Bayou sites (2,091) was greater than at the five Dickinson Bayou sites (1,055), but the...

A public-health assessment conducted for the Texas Department of Health and the Agency for Toxic Substances and Disease Registry concluded that exposure to contaminants through the aquatic food chain is an indeterminate human-health hazard in Lake Worth, Fort Worth, Texas. In 1999, the U.S. Geological Survey, in cooperation with the U.S. Air Force and in collaboration with the Texas...

No abstract available.

Data for all 366 known streamflow gain-loss studies conducted by the U.S. Geological Survey in Texas were aggregated. A water-budget equation that includes discharges for main channels, tributaries, return flows, and withdrawals was used to document the channel gain or loss for each of 2,872 subreaches for the studies. The channel gain or loss represents discharge from or recharge to...

Lake Pontchartrain is the largest estuary southern Louisiana. It is an important recreational, commercial, and environmental resource for New Orleans and southwestern Louisiana. This publication is part of a 5-year cooperative program led by the USGS on the geological framework and sedimentary processes of the Lake Pontchartrain Basin. This presentation is divided into two main parts: -...

Coevolved mutualisms, such as those between senita cacti, yuccas, and their respective obligate pollinators, benefit both species involved in the interaction. However, in these pollination mutualisms the pollinator's larvae impose a cost on plants through consumption of developing seeds and fruit. The effects of pollinators on benefits and costs are expected to vary with the abundance of

This report describes helicopter electromagnetic (HEM) data that were collected over portion of Everglades National Park and surrounding areas in south Florida. The survey was flown 9-14 December 1994. The original data set processed by the contractor, Dighem, are provided as an ASCII, xyz flight-line file. Apparent resistivity grids of the generated from the original data set and JPEG...

In an otherwise excellent review of metapopulation dynamics in amphibians, Marsh and Trenham (2001) make the following provocative statements (emphasis added): If isolation effects occur primarily in highly disturbed habitats, species translocations may be necessary to promote local and regional population persistence. Because most amphibians lack parental care, they areprime candidates...