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We assessed methylmercury (MeHg) concentrations across multiple ecological scales in the Edisto (South Carolina) and Upper Hudson (New York) River basins. Out-of-channel wetland/floodplain environments were primary sources of filtered MeHg (F-MeHg) to the stream habitat in both systems. Shallow, open-water areas in both basins exhibited low F-MeHg concentrations and decreasing...

Every five years since 1950, the U.S. Geological Survey (USGS) National Water Use Information Program (NWUIP) has compiled water-use information in the United States and published a circular report titled "Estimated use of water in the United States," which includes estimates of water withdrawals by State, sources of water withdrawals...

The Navajo (N) aquifer is an extensive aquifer and the primary source of groundwater in the 5,400-square-mile Black Mesa area in northeastern Arizona. Availability of water is an important issue in northeastern Arizona because of continued water requirements for industrial and municipal use by a growing population and because of...

Anomalously low values of friction observed in layers of submicron particles deformed in simple shear at high slip velocities are explained as the consequence of a one nanometer thick layer of water adsorbed on the particles. The observed transition from normal friction with an apparent coefficient near μ = 0.6...

Disruption to migration is a growing problem for conservation and restoration of animal populations. Anthropogenic barriers along migration paths can delay or prolong migrations, which may result in a mismatch with migration-timing adaptations. To understand the interaction of dams (as barriers along a migration path), seasonally changing environmental conditions, timing...

Agua Caliente Spring, in downtown Palm Springs, California, has been used for recreation and medicinal therapy for hundreds of years and currently (2008) is the source of hot water for the Spa Resort owned by the Agua Caliente Band of the Cahuilla Indians. The Agua Caliente Spring is located about...

The bull trout Salvelinus confluentus, a stream-living salmonid distributed in drainages of the northwestern United States, is listed as threatened under the Endangered Species Act because of rangewide declines. One proposed recovery action is the reconnection of tributaries in the Lemhi Basin. Past water use policies in this core area disconnected...

Chapter 2 focused on the environmental results of the ARP, presenting data from national monitoring networks on SO2 and NOx emissions, air quality, atmospheric deposition, surface water chemistry, and visibility. This chapter expands on this information by examining the most recent research into how ecosystems respond to acid deposition, especially...

To investigate rainfall-runoff conditions that generate post-wildfire debris flows, we instrumented and surveyed steep, small watersheds along the tectonically active front of the San Gabriel Mountains, California. Fortuitously, we recorded runoff-generated debris-flows triggered by one spatially restricted convective event with 28 mm of rainfall falling over 62 minutes. Our rain...

A groundwater-flow model of the Mississippi embayment was used to evaluate changes in water-level altitudes before (scenario 1) and after (scenario 2) the addition of wells that simulate potential future pumping from the Sparta aquifer in the Bayou Meto-Grand Prairie area of eastern Arkansas for the 30-year period from 2007...

Groundwater is an important resource for agricultural and municipal uses in the Mississippi embayment. Arkansas ranks first in the Nation for rice and third for cotton production, with both crops dependent on groundwater as a major source of irrigation requirements. Multiple municipalities rely on the groundwater resources to provide water...

Chlororespiration is common in shallow aquifer systems under conditions nominally identified as anoxic. Consequently, chlororespiration is a key component of remediation at many chloroethene-contaminated sites. In some instances, limited accumulation of reductive dechlorination daughter products is interpreted as evidence that natural attenuation is not adequate for site remediation. This conclusion...

What is the Mississippi Embayment? The Mississippi embayment study area encompasses approximately 78,000 square miles in eight States and includes large parts of Arkansas, Louisiana, Mississippi, and Tennessee, and smaller areas of Alabama, Illinois, Kentucky, and Missouri (fig. 1). The Mississippi embayment is essentially a basin that slopes toward the...

1. Salinity tolerance is one of several important physiological attributes that determine invasion success and the pattern of dispersal of introduced aquatic organisms. Introduced freshwater fishes able to tolerate elevated salinities have the potential to invade and exploit brackish-water (mixohaline) environments and use estuaries and coastal waters as 'bridges' for...

Mineralization of 14C-radiolabled vinyl chloride ([1,2-14C] VC) and cis-dichloroethene ([1,2-14C] cis-DCE) under hypoxic (initial dissolved oxygen (DO) concentrations about 0.1 mg/L) and nominally anoxic (DO minimum detection limit = 0.01 mg/L) was examined in chloroethene-exposed sediments from two groundwater and two surface water sites. The results show significant VC and...

Low-impact development (LID) is an approach to managing stormwater as near to its source as possible; this is accomplished by minimizing impervious surfaces and promoting more natural infiltration and evapotranspiration than is typically associated with developed areas. Two newly constructed LID sites in northeastern Ohio were studied to document their...

The High Plains aquifer, underlying almost 112 million acres in the central United States, is one of the largest aquifers in the Nation. It is the primary water supply for drinking water, irrigation, animal production, and industry in the region. Expansion of irrigated agriculture throughout the past 60 years has...

A study of the Transport of Anthropogenic and Natural Contaminants to public-supply wells (TANC study) was begun in 2001 as part of the U.S. Geological Survey National Water-Quality Assessment (NAWQA) Program. The study was designed to shed light on factors that affect the vulnerability of groundwater and, more specifically, water...

Floods are the most destructive natural hazard in the Nation, causing more deaths and financial loss in the 20th century than any other natural disaster. The most significant 20 riverine floods of the 20th century for which data are available have killed more than 1,843 people and caused more than...

Waterfowl in the genera Anas and Tadorna are suspected as vectors in the long‐distance transmission of highly pathogenic avian influenza H5N1. The former Soviet Republics of Central Asia are situated at an important migratory crossroads for these and other species of birds that bridges regions where the disease is prevalent. However, waterfowl movements through...

The National Climate Change and Wildlife Science Center (NCCWSC) has invested more than $20M since 2008 to put cutting-edge climate science research in the hands of resource managers across the Nation. With NCCWSC support, more than 25 cooperative research initiatives led by U.S. Geological Survey (USGS) researchers and technical staff...

Analysis of streamflow measurements and continuous records of streamflow provided insight into interaction of the groundwater system with the Clackamas River in northwestern Oregon. This report assesses gains and losses of the Clackamas River based on streamflow measurements made during previous hydrologic studies, decades of continuous streamflow data, and a...

A methyl tert-butyl ether (MTBE) / tert-butyl alcohol (TBA) plume originating from a gasoline spill in late 1994 at Vandenberg Air Force Base (VAFB) persisted for over 15 years within 200 feet of the original spill source. The plume persisted until 2010 despite excavation of the tanks and piping within...

Antibiotics are still widely applied in animal husbandry to prevent diseases and used as feed additives to promote animal growth. This could result in antibiotic resistance to bacteria and antibiotic residues in animals. In this paper, Enterobacteriaceae isolated from four integrated fish farms in Zhongshan, South China were tested for antibiotic resistance, tetracycline resistance genes, sulfonamide resistance genes, and class...

No abstract available....