Publications

The use of a semipermeable membrane device (SPMD) for dialysis in an organic solvent phase is an efficient alternative approach to separation of contaminants from large amounts of lipid (up to 50 grams or more) prior to organic chemical analysis. Passive separation of contaminants can be accomplished with a minimum of equipment and a comparatively small volume of solvent. This study examines the e

Although acid deposition is not considered a problem in the western United States, surface waters in high elevations and fish inhabiting these waters may be vulnerable to acidification. This study examined the sensitivity of a western salmonid to acid and aluminum stress. Yellowstone cutthroat trout (Oncorhynchus clarki bouvieri; YSC) were exposed for 7 d during each of four early life stages, or

Aquatic organisms accumulated selenium (Se) from inorganic and organic Se species via aqueous and food-chain exposure routes. We measured aqueous and food-chain Se bioaccumulation from selenate, selenite, and seleno-L-methionine in a laboratory food chain of algae (Chlamydomonas reinhardtii), daphnids (Daphnia magna), and fish (bluegill, Lepomis macrochirus). Selenium concentrations were monitored

The semipermeable membrane device (SPMD), consisting of a neutral lipid (triolein) enclosed in polyethylene layflat tubing, is demonstrated to be a highly efficient passive air sampler. These devices readily sequester lipophilic organic contaminants from the vapor phase. Specifically, the SPMDs are shown to concentrate polychlorinated biphenyl (PCB) residues from a laboratory atmosphere in a linea

1. A major cause of degradation and loss of stream fish is alteration of physical habitat within and adjacent to the channel. We describe a potentially efficient approach to fish restoration based upon the relationship between fluvial hydraulics, geomorphology, and those habitats important to fish.2. The aquatic habitat in a low-gradient, alluvial stream in the Ozark Plateaus physiographical provi

Industrial phosphate esters, both triaryl and alkyl aryl phosphate esters, are used as fire resistant hydraulic fluids and as fire retardant plasticizers (Lapp 1976). Hydraulic fluids probably represent the largest contribution of phosphate ester compounds released into the environment. Lapp (1976) estimated that 65 to 70 percent of all phosphate ester hydraulic fluids were utilized in automotive

Two chronic toxicity tests were conducted in which Daphnia magna were either continuously or intermittently exposed to bromoxynil octanoate (BO; as Buctril®) for 28 d. In the intermittent exposure test, daphnids were exposed to daily pulses of BO with 24-h mean concentrations equal to those in the continuous exposure test, and the peak concentrations were three times the 24-h mean values. After 28

Early-life-stage golden trout (Oncorhynchus aguabonita aguabonita) were exposed to acid and Al to examine the response and determine the sensitivity of a western, alpine salmonid to conditions simulating an episodic pH depression. Freshly fertilized eggs, alevins, and swim-up larvae were exposed for 7 d to one of 12 combinations of pH and Al, and surviving fish were held to 40 d post-hatch to dete

The November 1985 flood was the largest recorded in the South Branch Potomac River basin. Discharges exceeded values estimated for a recurrence interval of 500 yr at four of six stations in the basin. Flow velocities in the channel were as high as 4.6 m/s and may have exceeded 6 m/s at some locations; estimated values of unit stream power at U.S. Geological Survey gage locations were as high as 98

Widespread, intense rainfall in November 1985 produced floods that exceeded all historic events on Cheat River and most of its tributaries. Official discharge estimates for Cheat River ranged from 4,800 to 5,380 m3 /s (170,000-190,000 ft3/s) with a recurrence interval of >100 yr. In addition to considerable property damage and the loss of five lives, the November 1985 flood left a variety of depos

The heavy rains of November 3-5, 1985, produced record floods and extensive landsliding in the Potomac and Cheat River basins in West Virginia and Virginia (pl. 1). Although rainfall intensity was moderate, the storm covered a very large area and produced record floods for basins in the size range of 1000-10,000 km2. In addition, thousands of landslides were triggered on slopes underlain by shale

More than 3,000 landslides were triggered by heavy rainfall in the central Appalachian Mountains of West Virginia and Virginia, November 3-5, 1985. These landslides provided the opportunity to study spatial controls on landslides, magnitude and frequency of triggering events, and the effects of landslides on flood-induced geomorphic change. The study area consists of parts of the Wills Mountain an