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Vapor sorption of water, ethanol, benzene, hexane, carbon tetrachloride, 1,1,1-trichloroethane, trichloroethylene, tetrachloroethylene, and 1,2-dibromoethane on (Sanhedron) soil humic acid has been determined at room temperature. Isotherms for all organic liquids are highly linear over a wide range of relative pressure, characteristic of the partitioning (dissolution) of the organic compounds in...

Many fish culture systems require motoroperated valves to regulate water flow. The expense of commercial units can be prohibitive but, by using inexpensive components and a little assembly time, a manual valve can be motorized for a fraction of the cost....

Given sufficient oxygen, fish production can be limited by a multiplicity of factors. Accurate determination of production capacity requires something other than an estimate of the biomass at which ambient un-ionized ammonia will reach a recommended, non-site-specific, maximum safe concentration. A chronic (1- to 2-month) bioassay can be used to...

Nearly horizontal, quasi-periodic erosional features of 7-m average transverse wavelength and of order 100-m length occur in scattered locations from 3.5 to 9 km from the crater at Mount St. Helens under deposits of the lateral blast of May 18, 1980. We attribute the erosional features to scouring by longitudinal...

Five samples of hydrothermal fluids from two vent areas on the southern Juan de Fuca Ridge were analyzed for dissolved gases. Concentrations in the end-member hydrothermal fluid of H2 (270–527 μmol/kg), CH4 (82–118 μmol/kg), and CO2 (3920–4460 μmol/kg) are well above values in ambient seawater and are similar to concentrations reported for other...

A strong test of our understanding of the earthquake cycle is the ability to reproduce extant fault-bounded geological structures, such as basins and ranges, which are built by repeated cycles of deformation. Along strike-slip faults, the coseismic and interseismic deformation can be nearly equal in magnitude and opposite in sign,...

Geothermal drill hole CTGH-1, located near Breitenbush Hot Springs in the Cascade Mountains of northwest Oregon, was drilled to a depth of 1463 m. The maximum reported temperature at the bottom of the drill hole was 96.4??C. The drill core consists predominantly of basalt to basaltic andesite lava flows, tuffs,...

Water-resources investigations concerned with contaminant transport through aquifers comprised of very loose, unconsolidated sediments have shown that small-scale variations in aquifer characteristics can significantly affect solute transport and dispersion. Commonly, measurement accuracy and resolution have been limited by a borehole environment consisting of an annulus of disturbed sediments produced by...

Coomassie Brilliant Blue Agar was used to quantify the frequency of the A-layer phenotype in different isolates of Aeromonas salmonicida. Hydrophilic, non-clumping isolates of A. salmonicida consisted predominantly of the A-layer minus phenotype. These bacteria were avirulent by intraperitoneal injection into susceptible brook trout (Salvelinus fontinalis)...

Experiments were conducted to determine the effect of level of feeding (restricted feeding and feeding to satiation) and dietary variations in the balance of monovalent minerals on the arginine requirement of rainbow trout fingerlings. Based on growth and efficiency of feed utilization for growth, the arginine requirement was lower (3.5%...

Six commercially available diets varying in lipid, protein, water, ash, and carbohydrate contents were fed to Atlantic salmon (Salmo salar) for 2 years to determine if diet affected smoltification. Each month, from March to September of the second year, sampled fish were exposed to 33‰ seawater for 24 h to...

The treeless, tundra-plain of northern Alaska merges with the Arctic Ocean along a coastal area characterized by low tundra bluffs, and sparse coastal and delta dunes. Coastal engineering projects that aggrade or degrade permafrost will alter the geomorphology and rates of coastal processes by changing coastal stability. Similarly, projects that...

In late May 1986, the advancing Hubbard Glacier blocked the entrance to Russell Fiord near Yakutat, Alaska, creating a large ice-dammed lake. Runoff from the surrounding glaciated mountains raised the level of the lake to about 25 m above sea level by 8 October, when the ice dam failed. Remote...

Studies were conducted to determine the value of lupin flour as a replacement for full-fat soybean meal (FFSM) in the diet of rainbow trout (Salmo gairdneri). Energy and digestibility values for lupin were determined using a metabolism chamber and it was found that trout utilize lupin well. The gross energy,...

Large submarine lava flows with apparent volumes exceeding 10 km3 have recently been imaged on the deep ocean floor in various parts of the Pacific by means of GLORIA and SeaMarc side-looking sonar surveys. Such flows may produce thermal anomalies large enough to perturb the cyclic processes...

The North Atlantic Transect seismic reflection data, collected southwest of Bermuda, have been reinterpreted following post-stack migration and reveal two major intracrustal reflections. The shallower of these two events, located ∼1 s below the igneous basement, is a subhorizontal, undulating surface that in some places is continuous for as much...

Variations in streamwater temperature at the outlet of a 41-ha forested watershed at Panola Mountain in the Georgia Piedmont indicate that the initial rapid hydrologic response is caused by a combination of groundwater discharge and channel interception of rainwater. A storm in May 1986 caused a rapid increase in discharge...

In vitro and in vivo tests were carried out with tiamulin and gram-negative bacterial pathogens of fish. Determination of minimum inhibitory concentration for 51 strains of seven species of gram-negative bacterial pathogens showed that only strains of Vibrio anguillarum were sensitive at 1.6–6.25 ppm, while...

In the eastern and north-central United States, lakes and streams with low acid neutralizing capacity are at risk from acidity. Resource management agencies are interested in developing mitigation strategies that protect or restore fisheries in these waters. Addition of limestone (calcium carbonate) to improve water quality...

We used a MiniROVER MK II remotely operated vehicle (ROV) to collect ground-truth information on fish and their habitat in the Great Lakes that have traditionally been collected by divers, or with static cameras, or submersibles. The ROV, powered by 4 thrusters and controlled by the pilot at the surface,...

Hazard assessment of hundreds of observed and potential contaminants in fish, sediment, and water of the Great Lakes is necessary to determine impact on fishery sources and other aquatic biota. The hundreds of new compunds introduced each year have few measured properties. Mathematical models based on quantitative structure-activity relationships (QSARs)...

The first official earthquake forecast for California emphasizes the broad extent of the hazard and the uncertainties involved in predicting the next quakes. For the first time, researchers have reached to a consensus on the threat of large earthquakes to California, things look no worse for Los Angles than before. It...