Publications

Devils Lake is a 200 km2 terminal lake that contains sodium sulfate type water. Dissolved solids concentrations range from about 3,500 mg/L to 10,000 mg/L depending on location To investigate geochemical processes in the bottom sediments of Devils Lake, sediment cores were collected at two sites in the western half of the lake during a period of bottom water oxygen depletion. The upper...

No abstract available.

The Red River of the North drainage basin (herein referred to as Red River Basin) within the United States is a study unit under the U.S. Geological Survey (USGS) National Water-Quality Assessment (NAWQA) program. The overall goals of this program, initiated to better define the status and trends of the Nation’s water quality, are to address regional and national water-quality issues in...

No abstract available.

Four month-long field experiments investigated movements of water and solutes through unsaturated sand plains near Princeton, Minnesota, and Oakes, North Dakota. Atrazine and bromide were applied to bare soils and soils planted with corn. The field plots were irrigated according to local farming practices. At the end of each experiment, unsaturated soils were analyzed for atrazine and...

We examined sublethal responses of juvenile bluegills Lepomis macrochirus to aqueous cadmium in two 28-d tests (test I, 0.0-8.4 μg Cd per liter; test II, 0.0-32.3 μg Cd per liter) in an intermittent-flow diluter. The experimental design was completely randomized, with two replicates in each of eight treatments (seven Cd exposures and one water control with 25 fish per replicate). Cadmium...

We exposed juvenile bluegill (Lepomis macrochirus) to ~1000 mg∙L−1 of continuously suspended river sediment in a 28-d test with six treatments (randomized block with one sediment-free control and five sediments ranging from 1.3 to 21.4 μg Cd∙g dry weight−1). Each treatment had three replicates, each with 25 fish. Growth was reduced by exposure to suspended sediment, probably due to...

Antifungal agents are needed to maintain healthy stocks of fish in the intensive culture systems currently employed in fish hatcheries. Malachite green has been the most widely used antifungal agent; however, its potential for producing teratology in animals and fish precludes further use in fish culture. Preliminary studies at the National Fisheries Research Center, La Crosse, WI, USA...

The U.S. Geological Survey began a research project at the site of a crude-oil spill near Bemidji, Minnesota in 1983. The project is part of the U.S. Geological Survey's Toxic Substances Hydrology Program. The objectives of research at the site are to obtain an understanding of the mobilization, transport, and fate of petroleum derivatives in the shallow subsurface and to use this...

The Minnesota Management Systems Evaluation Area project is part of a multi-scale, inter-agency initiative to evaluate the effects of agricultural management systems on water quality in the midwest corn belt. The research area is located in the Anoka Sand Plain about 5 kilometers southwest of Princeton, Minnesota. The ground-water-quality monitoring network within and immediately...

Early-life-stage (ELS) toxicity tests were conducted to determine the effect of selected water temperatures on the toxicity of 4-nitrophenol and 2,4-dinitrophenol to rainbow trout (Oncorhynchus mykiss). NOECs were determined for growth and mortality at selected time intervals and water temperatures of 7, 12, and 17°C. As tests progressed, NOECs leveled to constant time-independent values...

Snowy Egret (Egretta thula) and Black-crowned Night-Heron (Nycticorax nycticorax) nestlings from colonies in Texas, Rhode Island, and California and Great Egret (Casmerodius albus) nestlings from Texas were examined for eustrongylidosis, or infection by the parasitic nematode Eustrongylides spp. In 31% (24/77) of all broods examined, at least one nestling was infected. Snowy Egret broods...