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Addresses the significance of changes in summer thermal stratification patterns of Adirondack lakes affected by acidification to cold-water fish populations inhabiting these sensitive lakes. Brook trout Salvelinus fontinalis is the primary cold-water fish species indigenous to acid-sensitive lakes in the Adirondack region of N New York State; the ability of these lakes to sustain...

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 radiometrically...

Transport of a radioisotope in a sediment-water system can be retarded by sorption of the isotope to solid; which is controlled by the affinity of the radioisotope for the sediment particles. In order to study trace metal and ra- dionuclide mobility on the sea floor, the following measurements were carried...

Approximately 2550 km of single-channel high-resolution seismic reflection profiles have been interpreted and calibrated with lithological and geochronological information from four representative piston cores and one grab sample to provide a regional stratigraphie framework for the subbottom deposits of Lake Ontario. Five units overlying Paleozoic bedrock were identified and mapped....

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...

Measurement of the rate and direction of ground water flow beneath Wollaston Beach, Quincy, Massachusetts by use of a heat-pulsing flowmeter shows a mean velocity in the bulk sediment of 40 cm d−1. The estimated total discharge of ground water into Quincy Bay during October 1990 was 1324–2177 m3 d−1,...

We review recent accounts of the foraging ecologies of  five species of small auklets found in the Bering Sea. These birds eat a wide variety of zooplankton and micronekton. Least Auklets Aethia pusilla and Whiskered Auklets A. pygmaea, as far as is known, primarily eat copepods, whereas Created Auklets A. cristatella appear to specialize...

Chick mass and growth during a six-day period were investigated among California Gulls (Larus californicus) in 1979 and 1980. In broods of two, levels of hatching asynchrony between siblings ranging from 0 - 4 days were observed. Hatching asynchrony resulted in initial mass differences between siblings that persisted and accelerated...

Time-series data on Zn/Cu weight ratios from portal effluent compositions [(Zn/Cu)water] at Iron Mountain, California, show seasonal variations that can be related to the precipitation and dissolution of melanterite [(FeII,Zn,Cu)SO4·7H2O]. Mine water and actively forming melanterite were collected from underground mine workings and chemically analyzed. The temperature-dependent solubility of Zn-Cu-bearing...

The Leviathan and Bryant Creek (LBC) drainage system, on the border of California and Nevada, flows through overburden and waste from a former open-pit sulfur mine. The drainage contains acid mine waters with high concentrations of several trace elements, including Cu, Zn, and As, derived from oxidative weathering of sulfides...

The San Pedro River of southeast Arizona is a north-flowing tributary of the Gila River. The area of the drainage basin upstream of the 40-km-long study reach is about 3,200 km2. This study traces the historical evolution of the San Pedro River channel—specifically, the deepening, widening, and sediment deposition that...

Montana Power Company, Inc. (MPC) submitted a final license application to the Federal Energy Regulatory Commission (FERC) on November 30, 1992. In this application, MPC proposed a plan for the protection of fish, wildlife, habitat, and water-quality resources. One concern was maintenance of woody riparian vegetation along the...

A geographic information system (GIS) was used to determine the relation between the stream-water quality and underlying geology in Roberts Creek watershed, Clayton County, Iowa, for base-flow conditions during the spring and summer of 1988–90. Geologic, stream, basin and subbasin boundaries, and water-quality sampling-site coverages were created by digitizing available...

Numerical simulation was used to study steady liquid water movement in a 5-m by 5-m vertical section containing a hypothetical fracture network under conditions of variable saturation. The fracture network was assumed to be embedded within an impermeable rock matrix. Three variations of a network were considered. The “mixed” network...

Detailed laser-Doppler velocity and Reynolds stress measurements over fixed two-dimensional bed forms are used to investigate the coupling between the mean flow and turbulence and to examine effects that play a role in producing the bed form instability and finite amplitude stability. The coupling between the mean flow and the...

Concentrations of the Chlorofluorocarbons (CFCs) CFC-11 and CFC-12 were determined in groundwater from coastal plain sediments of the Delmarva Peninsula. CFC-modeled ages were calculated independently for CFC-11 and CFC-12, and agreed to within 2–3 years in the majority of the waters. Recharge temperatures, determined from dissolved...

An adaptive estimation scheme is used to obtain the integral scale and variance of the log-fluctuating conductivity at the Cape Cod site based on the fast Fourier transform/stochastic model of Deng et al. (1993) and a Kalmanlike filter. The filter incorporates prior estimates of the unknown parameters with...

No abstract available....

Selected herbicides, atrazine (2-chloro-4-ethylamino-6-isopropylamino-s-triazine) metabolites, and NO−3 were examined in near-surface unconsolidated and bedrock aquifers in the midcontinental USA to study the hydrogeologic, spatial, and seasonal distribution of these contaminants. Groundwater samples were collected from 303 wells during the spring and late summer of 1991. At least one herbicide or atrazine...

The US Geological Survey, US Department of Agriculture, and US Environmental Protection Agency are conducting research and regional assessments in support of policy alternatives intended to protect water resources from agricultural chemical contamination. The mid-continent was selected because of the intense row crop agriculture and associated herbicide application in this...

No abstract available....

We determined the prolonged swimming performance of two size-classes of northern squawfish Ptychocheilus oregonensis at 12 and 18°C. The percentage of fish fatigued was positively related to water velocity and best described by an exponential model. At 12°C, the velocity at which 50% of the fish fatigued (FV50) was estimated...

Two experiments were conducted with rainbow trout Oncorhynchus mykiss to investigate the influence of several diets and supplemental phosphorus on discharges of phosphorus in hatchery effluent water. A diet was formulated to contain no fish meal and a reduced level of non‐phytin phosphorus (approximately 0.9%) provided, in part, by supplemental defluorinated rock...

We used biotelemetry to study the movements of 23 adult shortnose sturgeons Acipenser brevirostrum and 23 subadult Atlantic sturgeons Acipenser oxyrhynchus oxyrhynchus in the lower 46 km of the Merrimack River between 1987 and 1990. Shortnose sturgeons used two freshwater reaches and one saline reach annually. Sexually mature fish began moving upriver from freshwater...