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A recent article presented geochemical and microbial evidence establishing metabolic adaptation to and in-situ reductive dechlorination of trichloroethene (TCE) in a fractured dolomite aquifer. This study was designed to further explore site conditions and microbial populations and to explain previously reported enhancement of reductive dechlorination by the addition of pulverized...

Area requirements of grassland birds have not been studied except in tallgrass prairie. We studied the relation between both species-occurrence and density and patch size by conducting 699 fixed-radius point counts of 15 bird species on 303 restored grassland areas in nine counties in four northern Great Plains states. Northern...

Shuidonggou is unique within the Chinese Palaeolithic sequence and its assemblage is reminiscent of Upper Palaeolithic core-and-blade technologies in Mongolia and southern Siberia. Limited chronological controls have prevented evaluation of this technology in both the Chinese and greater Eurasian Palaeolithic. Dating of recently discovered hearths at Locality 2 places Shuidonggou...

The water quality, habitats, and biota of streams in the upper Animas River watershed of Colorado, USA, are affected by metal contamination associated with acid drainage. We determined metal concentrations in components of the food web of the Animas River and its tributaries - periphyton (aufwuchs), benthic invertebrates, and livers...

Two species of sculpins (Cottidae), the grubby, Myoxocephalus aenaeus, and the shorthorn sculpin, M. scorpius, were studied in rocky tidepools along the coast of Maine. Fishes were captured and measured during 116 sampling trips between 1979 and 1996. Both of these species of sculpins are from the northwestern Atlantic Ocean...

Image data from the DS1 encounter with Asteroid 9969 Braille and data from a coordinated ground-based photometric observing campaign are combined to study the physical properties of this small Mars crosser. From telescope data the object's brightness was found to vary by up to 0.5 mag from night to night,...

In October 1988, a cruise ship dropped its anchor on a coral reef in Virgin Islands National Park, St. John, creating a distinct scar roughly 128 m long and 3 m wide from a depth of 22 m to a depth of 6 m. The anchor pulverized coral colonies and...

Rocky Mountain Arsenal (RMA) National Wildlife Area, near Denver, Colorado, is a Superfund site contaminated by past military and industrial uses, including pesticide manufacturing. From an ecosystem standpoint, the most critical contaminants at RMA are certain cyclodiene insecticides and metabolites, p,p′-DDE, p,p′-DDT, arsenic, and mercury. Bats are important...

A 16-year study of a hydrocarbon plume shows that the extent of contaminant migration and compound-specific behavior have changed as redox reactions, most notably iron reduction, have progressed over time. Concentration changes at a small scale, determined from analysis of pore-water samples drained from aquifer cores, are compared with concentration changes at...

The dust logger design is based on a decade of experience in the use of light sources to measure optical properties of deep Antarctic ice. Light is emitted at the top of the instrument by side-directed LEDs, scattered or absorbed by dust in the ice surrounding the borehole, and collected...

Mosses and lichens are important components of boreal landscapes [Vitt et al., 1994; Bubier et al., 1997]. They affect plant productivity and belowground carbon sequestration and alter the surface runoff and energy balance. We report the use of multiresolution satellite data to map moss and lichens over the BOREAS region...

The first appearance of Hindeodus parvus (Kozur & Pjatakova) at the Permian-Triassic (P-T) GSSP level (base of Bed 27c) at Meishan is here confirmed. Hindeodus changxingensis Wang occurs from Beds 26 to 29 at Meishan and appears to be restricted to the narrow boundary interval immediately above the main mass...

During 1997 we evaluated reproductive success in colonial water birds nesting in the Lower Rio Grande Valley (LRGV), Texas, and correlated success with concentrations of contaminants in eggs. We also measured steroid hormones and gonadosomatic index (GSI) as biomarkers of endocrine effects in common carp (Cyprinus carpio). Nest and fledging...

Although considerable uncertainty and disagreement prevail concerning the world's gas-hydrate resources, the estimated amount of gas in those gas-hydrate accumulations greatly exceeds the volume of known conventional gas reserves. However, the role that gas hydrates will play in contributing to the world's energy requirements will ultimately depend less on the...

We calculate a density model of the lithosphere of the southwestern United States through an integrated analysis of gravity, seismic refraction, drill hole, and geological data. Deviations from the average upper mantle density are as much as ?? 3%. A comparison with tomographic images of seismic velocities indicates that a...

Analysis of suspended-sediment concentration data in San Francisco Bay is complicated by spatial and temporal variability. In situ optical backscatterance sensors provide continuous suspended-sediment concentration data, but inaccessibility, vandalism, and cost limit the number of potential monitoring stations. Satellite imagery reveals the spatial distribution of surficial-suspended sediment concentrations in the...

The objective of this paper is to identify water-flow patterns in part of an active landslide, through the use of numerical simulations and data obtained during a field study. The approaches adopted include measuring rainfall events and pore-pressure responses in both saturated and unsaturated soils at the site. To account...

Past and current dieback of Cercidium microphyllum, a dominant, drought-deciduous tree in the Sonoran Desert, was investigated at Tumamoc Hill, Tucson, Arizona, USA. Logistic regression predicted that the odds of a Cercidium plant being alive should decrease with increasing circumference, association with the columnar cactus Carnegiea gigantea, and occurrence on...

Regional extension of a brittle overburden and underlying salt causes differential loading that is thought to initiate the rise of reactive diapirs below and through regions of thin overburden. We present a modern example of a large salt diapir in the Dead Sea pull-apart basin, the Lisan diapir, which we...

Invasion by the red imported fire ant, Solenopsis invicta, has had negative impacts on individual animal and plant species, but little is known about how S. invicta affects complex mutualistic relationships. In some eastern forests of North America, 30% of herbaceous species have ant-dispersed seeds. We conducted experiments to determine...

Na+-K+-2Cl−cotransporter abundance and location was examined in the gills of Atlantic salmon (Salmo salar) during seawater acclimation and smolting. Western blots revealed three bands centered at 285, 160, and 120 kDa. The Na+-K+-2Cl−cotransporter was colocalized with Na+-K+-ATPase to chloride cells on both the primary filament and secondary lamellae. Parr acclimated...

Ground-water sampling techniques were modified to reduce random low-level contamination during collection of filtered water samples for determination of trace-element concentrations. The modified sampling techniques were first used in New Jersey by the US Geological Survey in 1994 along with inductively coupled plasma-mass spectrometry (ICP-MS) analysis to determine the concentrations...

Decades of quantitative measurement indicate that roots can mechanically reinforce shallow soils in forested landscapes. Forests, however, have variations in vegetation species and age which can dominate the local stability of landslide-initiation sites. To assess the influence of this variability on root cohesion we examined scarps of landslides triggered during...

A rapid method for identifying specific bacteria from complex biological mixtures using immunomagnetic separation coupled to matrix-assisted laser desorption/ionization time-of-flight mass spectrometry has been developed. The technique employs commercially available magnetic beads coated with polycolonal antibodies raised against specific bacteria and whole cell analysis by MALDI-MS. A suspension of a...

A DNA vaccine against a fish rhabdovirus, infectious hematopoietic necrosis virus (IHNV), was shown to provide significant protection as soon as 4 d after intramuscular vaccination in 2 g rainbow trout (Oncorhynchus mykiss) held at 15°C. Nearly complete protection was also observed at...