Publications

This publication, Environmental Toxicology and Risk Assessment: Seventh Volume, contains papers presented at the Seventh Symposium on Toxicology and Risk Assessment: Ultraviolet Radiation and the Environment, held 7-9 April, 1997 in St. Louis, MO. The symposium, the 24th in a series on environmental toxicology, was sponsored by Committee E-47. Edward E. Little, of the U.S. Geological...

Catahoula Lake, central Louisiana, is a RAMSAR Convention Wetland of International Importance and among the most important wintering and staging areas for waterfowl in North America. To evaluate exposure rates in Catahoula Lake waterfowl 5 years after a ban on use of lead shot, we determined the prevalence of ingested shot and diets of canvasbacks (Aythya valisineria) and lesser scaup (A...

Approximately 170 Mgal/d (million gallons per day) of ground- and surface-water was withdrawn from the Barataria-Terrebonne Basins in 1995. Of this amount, surface water accounted for 64 percent ( 110 MgaVd) of the total withdrawal rates in the basins. The largest surface-water withdrawal rates were from Bayou Lafourche ( 40 Mgal/d), Bayou Boeuf ( 14 MgaVd), and the Gulf Intracoastal...

No abstract available

The natural establishment of woody seedlings on abandoned agricultural fields was investigated at sites in Louisiana and Mississippi. Series of disked and undisked plots originating at forest edges and oriented in cardinal directions were established on fields at each site. During the firest 2 years, seedling recruitment was dominated by sweetgum, sugarberry, and elms at both sites...

Clear-water contraction and abutment scour data were collected at 128 bridge sites in South Carolina. In the sandy soils of the Coastal Plain, clear-water-scour data were collected at 63 sites (scour depths ranged from 0.4 to 7.2 meters.) In the clayey soils of the Piedmont, clear-water-scour data were collected at 47 sites (scour depths ranged from 0 to 1.4 meters.) In the sandy, clayey...

Three different types of Nuttall oak (Quercus nuttallii Palmer) seedlings were planted on floodprone, former cropland in Mississippi, Louisiana, and Texas. The three types of 1+0 seedlings planted at each site in January and February of 1995 were bareroot seedlings, seedlings grown in 164 square centimeters plastic containers, and container grown seedlings inoculated with vegetative...

Most wetland losses in the southern region over the past 200 years have occurred in bottomland hardwood forests. By 1980 the original extent of palustrine bottomland in Texas had been reduced by 63%, from roughly 16 to 6 million acres. Additional losses have occurred during more recent years as a result of conversion to agriculture and timber harvests; these factors and the need to...

Benthic invertebrate samples were collected from 23 pools in the Upper Mississippi River (UMR) and from one station in the Saint Croix River (SCR) as part of a study to assess the effects of the extensive flooding of 1993 on sediment contamination in the UMR system. Sediment contaminants of concern included both organic and inorganic compounds. Oligochaetes and chironomids constituted...

To assess the extent of sediment contamination in the Upper Mississippi River (UMR) system after the flood of 1993, sediment samples were collected from 24 of the 26 navigational pools in the river and from one site in the Saint Croix River in the summer of 1994. Whole-sediment tests were conducted with the amphipod Hyalella azteca for 28 days measuring the effects on survival, growth...

Tree ring analysis was used to document the long-term effects of municipal wastewater on the growth rate of baldcypress (Taxodium distichum (L.) Rich.]. The study site, a swamp in St. Martin Parish, Louisiana, has received municipal wastewater for the last 40 years. Growth chronologies from 1920 to 1992 were developed from cross-dated tree core samples taken from treated and control...

Ecological change is constant and profound, yet it often occurs at temporal and spatial scales that are difficult to measure and interpret. This publication demonstrates how diverse data bases, archived in different formats and at numerous locations, can be brought together to provide an integrated perspective on the relationship between land use and landcover change. The authors provide...