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Current toxicological methods often miss contaminant effects, particularly when immune suppression is involved. The failure to recognize and evaluate indirect and sublethal effects severely limits the applicability of those methods at the population level. In this study, the Vitality model is used to evaluate the population level effects of a...

High-resolution historical (1942) and recent (1994) digital terrain models were derived from aerial photographs along the Big Sur coastline in central California to measure the long-term volume of material that enters the nearshore environment. During the 52-year measurement time period, an average of 21 000 ?? 3100 m3 km-1 a-1...

The East Tianshan is a remote Gobi area located in eastern Xinjiang, northwestern China. In the past several years, a number of gold, porphyry copper, and Fe(-Cu) and Cu-Ag-Pb-Zn skarn deposits have been discovered there and are attracting exploration interest. The East Tianshan is located between the Junggar block to...

Diurnal cycles of streamflow in snow‐fed rivers can be used to infer the average time a water parcel spends in transit from the top of the snowpack to a stream gauge in the river channel. This travel time, which is measured as the difference between the hour of peak snowmelt...

We examined aboveground biomass dynamics, aboveground net primary production (ANPP), and woody detritus input in an old Sequoia sempervirens stand over a three-decade period. Our estimates of aboveground biomass ranged from 3300 to 5800 Mg ha-1. Stem biomass estimates ranged from 3000 to 5200 Mg ha-1. Stem biomass declined 7%...

A shift in national policy toward stronger environmental protection began in the United States in about 1970. Conversely, urban land use, population, energy consumption, and vehicle use have increased greatly since then. To assess the effects of these changes on water quality, the U.S. Geological Survey used sediment cores to...

A new morphological-behaviour model is used to simulate evolution of coastal morphology associated with cross-shore translations of the shoreface, barrier, and estuary. The model encapsulates qualitative principles drawn from established geological concepts that are parameterized to provide quantitative predictions of morphological change on geological time scales (order 10 3 years),...

Grubby (Myoxocephalus aenaeus, Cottidae) is a common benthic fish of inshore waters and estuaries of eastern Long Island Sound; however, little information exists on their life history or population demographics. This study utilised a long-term data series (1976-2002) to assess grubby life history and population demographics and explores trends in...

Controls on mudstone deposition at high latitudes are poorly known relative to low latitudes. In recent sediments deposited in these environments, ice significantly influences sediment transport and primary productivity. The products of ice transport are relatively well known in glacimarine settings, but are less well known from below melting sea...

A set of Pennsylvanian coals from the North American coal basins, ranging in vitrinite reflectance from 0.65% to 1.75%, was examined, with special emphasis on the optical properties of pseudovitrinite. The results suggest that pseudovitrinite originates from the same material as telocollinite. Slits in the pseudovitrinite seem to have originated...

Pennsylvanian glacioeustatic cyclothems exposed in Kansas and adjacent areas provide a unique opportunity to test models of the impact of relative sea level and climate on stratal architecture. A succession of eight of these high-frequency sequences, traced along dip for 500 km, reveal that modest climate shifts from relatively dry-seasonal...

One of the most frequently detected organic chemicals in a nationwide study concerning the effects of wastewater on stream water quality conducted in the year 2000 was the widely used insect repellant N,N-diethyl-m-toluamide (DEET). It was detected at levels of 0.02 μg/L or greater in 73% of the stream sites...

The Hazard Assessment component of the U.S. National Tsunami Hazard Mitigation Program has completed 22 modeling efforts covering 113 coastal communities with an estimated population of 1.2 million residents that are at risk. Twenty-three evacuation maps have also been completed. Important improvements in organizational structure have been made with the...

Perchlorate inhibits iodide uptake by thyroid follicles and lowers thyroid hormone production. Although several effects of perchlorate on the thyroid system have been reported, the utility of these pathologies as markers of environmental perchlorate exposures has not been adequately assessed. The present study examined time-course and concentration-dependent effects of perchlorate...

Question:Can patterns of species frequency in an old-field be explained within the context of a metapopulation model? Are the patterns observed related to time, spatial scale, disturbance, and nutrient availability?Location:Upland and lowland old-fields in Illinois, USA.Method:Species richness was recorded annually for...

Nine stream sites in the Blackfoot River, Salt River, and Bear River watersheds in southeast Idaho, USA were sampled in May 2001 for water, surficial sediment, aquatic plants, aquatic invertebrates, and fish. Selenium was measured in these aquatic ecosystem components, and a hazard assessment was performed on the data. Water...

Texas Horned Lizards, Phrynosoma cornutum, were tracked using fluorescent powder to determine exact daily movements. Daily linear movements and daily space use were compared between adult males and females. Lizards that traveled the greatest linear distances also covered the largest areas. In Oklahoma, adults emerge from hibernation in late April...

To assess the effects of timber harvesting on headwater streams in upland forests, benthic community structure was contrasted among four dominant forest management types (old growth, red alder-dominated young growth, conifer-dominated young growth, clearcut) and instream habitats (woody debris, cobble, gravel) in southeastern Alaska. Benthos in streams of previously harvested...

Analysis of in-situ-produced 10Be and 26Al in 52 fluvial sediment samples shows that millennial-scale rates of erosion vary widely (7 to 366 m Ma-1) through the lithologically and topographically complex Rio Puerco Basin of northern New Mexico. Using isotopic analysis of both headwater and downstream samples, we determined that the...

Watershed-based sampling design and assessment tools help serve the multiple goals for water quality monitoring required under the Clean Water Act, including assessment of regional conditions to meet Section 305(b), identification of impaired water bodies or watersheds to meet Section 303(d), and development of empirical relationships between causes or sources...

Capture–recapture studies are powerful tools for studying animal population dynamics, providing information on population abundance, survival rates, population growth rates, and selection for phenotypic traits. In these studies, the probability of observing a tagged individual reflects both the probability of the individual surviving to the time of recapture and the...

Management of wildlife in suburban environments involves a complex set of interactions between both human and wildlife populations. Managers need additional tools, such as models, that can help them assess the status of wildlife populations, devise and apply management programs, and convey this information to other professionals and the public....

Despite evidence of annual spawning by white sturgeon Acipenser transmontanus in rivers of the northwestern United States and Canada, in some years and locations little or no recruitment of age-0 white sturgeon has been observed. We examined the vulnerability of white sturgeon larvae and juveniles to predation to further understand...

National and international policy makers and industry require accurate information on coal, including coal quality data, to make informed decisions regarding international import needs and export opportunities, foreign policy, technology transfer policies, foreign investment prospects, environmental and health assessments, and byproduct use and disposal issues. Unfortunately, the information needed is...

The Karst Feature Database (KFD) of Minnesota is a relational GIS-based Database Management System (DBMS). Previous karst feature datasets used inconsistent attributes to describe karst features in different areas of Minnesota. Existing metadata were modified and standardized to represent a comprehensive metadata for all the karst features in Minnesota. Microsoft...