Publications

Plants possessing generalized dispersal syndromes are likely to be more invasive than those relying on specialist dispersal agents. To address this issue on a local and regional scale, avian seed dispersal of the invasive alien Chinese tallow tree (Sapium sebiferum (L.) Roxb.) was assessed in forests and spoil areas of South Carolina and along forest edges in Louisiana during the 1997-99...

This report describes the thickness and areal extent of the Sparta aquifer, identifies sands within the fresh-water extent of the aquifer, and presents data and a map that illustrate the generalized potentiometric surface (water levels) during October 1996. The report includes a detailed geophysical log, structure contour maps, hydrogeologic sections, and hydrographs of water levels in...

Increased nutrient loading to the Gulf of Mexico from off-continent flux has been identified as contributing to the increase in the areal extent of the low dissolved-oxygen zone that develops annually off the Louisiana and Texas coast. The proximity of the Yazoo River Basin in northwestern Mississippi to the Gulf of Mexico, and the intensive agricultural activities in the basin have led...

The primary criteria for community participation in the National Flood Insurance Program is the adoption and enforcement of floodplain management requirements that minimize the potential for flood damages to existing and proposed development in flood-hazard areas. This report provides base flood elevations (BFE) for a 100-year recurrence-interval flood for use in the management and...

High performance liquid chromatography coupled with programmable fluorescence detection was employed for the determination of 15 priority pollutant polycyclic aromatic hydrocarbons (PPPAHs) in water, sediment, and semipermeable membrane devices (SPMDs). Chromatographic separation using this analytical method facilitates selectivity, sensitivity (ppt levels), and can serve as a non...

We used a large data set of African, Neotropical, and North American fishes to examine the frequency with which fishes have empty stomachs (nspecies = 254; nindividuals = 36 875). Mean percentage of empty stomachs was low across all fishes (16.2 ± 1.2%) but varied from 0% to 79.4% among individual species. Nocturnal fishes had empty stomachs more frequently than diurnal fishes. Trophic

Water resources data for water year 2000 for Iowa consists of records of stage, discharge, and water quality of streams; stage and contents of lakes and reservoirs; and water levels and water quality of ground water. This report, in two volumes, contains stage or discharge records for 126 gaging stations; stage or contents records for 9 lakes and reservoirs; water-quality records for 4...

The advent of analog and digital video has provided amateur photographers with professional-like technology to capture dynamic images with ease and clarity. Videography is also rapidly changing traditional business and scientific applications. In the natural sciences, camcorders are being used largely to record timely observations of plant and animal behavior or consequence of some...

Water-quality data collected during 1999 and 2000 as part of the first nationwide reconnaissance of the occurrence of pharmaceuticals, hormones, and other organic wastewater contaminants (OWCs) are presented in this report. A network of 139 streams in 30 states were sampled and analyzed for 95 different OWCs using five new research methods developed by the U.S. Geological Survey. Site...

The chemistry and toxicity of base flow and urban stormwater were characterized to determine if urban stormwater was degrading the water quality of the Pearson Creek and Wilsons Creek Basins in and near the city of Springfield, Greene County, Missouri. Potentially toxic components of stormwater (nutrients, trace metals, and organic compounds) were identified to help resource managers...

Aerial surveys of American White Pelicans (Pelecanus erythrorhynchos) were conducted over coastal Louisiana and the delta region of Mississippi on 1-2 days during December, February, and April each year from 1997 to 1999. Additional surveys were conducted in coastal Texas and Mexico during January 1998 and 1999. The numbers, location, and habitat of all pelicans observed were recorded...

Soil gas was sampled using active sampling techniques and passive collectors at three sites in Tennessee to evaluate the effectiveness of these techniques for locating chlorinated solvent sources and flowpaths in karst aquifers. Actively collected soil gas samples were analyzed in the field with a portable gas chromatograph, and the passive soil gas collectors were analyzed in the lab...