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Efforts to manage several trout fisheries in Tennessee have been stymied by conflicts between management agencies and angler groups. To assist in preventing such conflicts in the future, we examined attitudes and motivations of trout anglers who fished eight tailwater fisheries in Tennessee during 2001-2002. Using a stratified random sampling...

We present a method to solve for slowness models from surface-source downhole-receiver seismic travel-times. The method estimates the slownesses in a single inversion of the travel-times from all receiver depths and accounts for refractions at layer boundaries. The number and location of layer interfaces in the model can be selected...

The largest abrupt climatic reversal of the Holocene interglacial, the cooling event 8.6–8.2 thousand years ago (ka), was probably caused by catastrophic release of glacial Lake Agassiz-Ojibway, which slowed Atlantic meridional overturning circulation (AMOC) and cooled global climate. Geophysical surveys and sediment cores from Chesapeake Bay reveal the pattern of...

As part of an ongoing cooperative effort between USGS, NASA and USACE, the barrier islands within the right-front quadrant of Hurricane Katrina were surveyed with airborne lidar both before and after landfall. Dauphin Island, AL was located the farthest from landfall and wave runup intermittently overtopped its central and western...

As part of a larger investigation, northern pike (n = 158; Esox lucius) were collected from ten sites in the Yukon River Basin (YRB), Alaska, to document biomarkers and their correlations with organochlorine pesticide (total p,p'-DDT, total chlordane, dieldrin, and toxaphene), total polychlorinated biphenyls (PCBs), and elemental contaminant (arsenic, cadmium,...

One of the fastest growing areas of natural gas production is coal bed methane (CBM) due to the large monetary returns and increased demand for energy from consumers. The Powder River Basin, Wyoming is one of the most rapidly expanding areas of CBM development with projections of the establishment of...

Advanced borehole-geophysical methods were used to assess the geohydrology of fractured crystalline bedrock in 31 of 64 boreholes on the southern part of Manhattan Island, NY in preparation of the construction of a new water tunnel. The study area is located in a highly urbanized part of New York City....

A Late Quaternary spit-shoreline complex on the northern shore of Pleistocene Lake Mojave of southeastern California, USA was studied with the goal of comparing accelerator mass spectrometry (AMS) radiocarbon, luminescence, electron spin resonance (ESR), terrestrial cosmogenic radionuclide (TCN) surface exposure, amino acid racemization (AAR) and U-series dating methods. The pattern...

We assessed species-specific coverage (km2) of a submerged aquatic vegetation (SAV) community in the fresh and upper oligohaline Potomac Estuary from 1985 to 2001 using a method combining field observations of species-proportional coverage data with congruent remotely sensed coverage and density (percent canopy cover) data. Biomass (estimated by density-weighted coverage)...

Volcanic hazards assessments at andesite stratovolcanoes rely on the assessment of frequency and magnitude of past events. The identification and correlation of proximal and distal andesitic tephra, which record the explosive eruptive history, are integral to such assessments. These tephra are potentially valuable stratigraphic marker beds useful to the temporal...

Turnagain Arm is a semidiurnal hypertidal estuary in southeastern Alaska with a recorded tidal range of 9 m. Contorted bedding and flow rolls preserved in tidal sediments within the estuary have previously been interpreted as resulting from the Mw 9.2 Great Alaskan earthquake of 1964. Horizons of flow rolls between...

The objective of this simulation study was to create an age-structured population model for horseshoe crabs (Limulus polyphenols) in the Delaware Bay region using best available estimates of age-specific mortality and recent harvest levels. Density dependence was incorporated using a spatial model relating egg mortality with abundance of spawning females....

This paper presents recent state-of-the-art developments to obtain displacements and drift ratios for seismic monitoring and damage assessment of buildings. In most cases, decisions on safety of buildings following seismic events are based on visual inspections of the structures. Real-time instrumental measurements using GPS or double integration of accelerations, however,...

We measured velocity and channel geometry in 10 reaches (bed gradient = 0.08-0.21) of a predominantly step-pool channel, the Rio Cordon, Italy, over a range of discharges (3-80% of the bankfull discharge). The resulting data were used to compute flow resistance. At-a-station hydraulic geometry relations indicate that in most reaches,...

Translocations are used increasingly to conserve populations of rare freshwater mussels. Recovery of translocated mussels is essential to accurate assessment of translocation success. We designed an experiment to evaluate the use of passive integrated transponder (PIT) tags to mark and track individual freshwater mussels. We used eastern lampmussels (Lampsilis radiata...

The formation of amphibian population structure is directly affected by predation. Although aquatic predators have been shown to have direct negative effects on larval salamanders in laboratory and field experiments, the potential impacts of gape-limited fish on larval salamander growth has been largely underexplored. We designed an enclosure experiment conducted...

Celastrus orbiculatus is an invasive liana in the Eastern United States. Its native congener, C. scandens, is less common and declining in the Northeast. The correct identification of these two species is often difficult because of their similar vegetative characteristics. Using morphological characteristics of both species growing naturally along a sand dune/forest...

Environmental tracers are used to estimate groundwater ages and travel times, but the strongly heterogeneous nature of many subsurface environments can cause mixing between waters of highly disparate ages, adding additional complexity to the age-estimation process. Mixing may be exacerbated by the presence of wells because long open intervals or...

The boundaries between mangroves and freshwater hammocks in coastal ecotones of South Florida are sharp. Further, previous studies indicate that there is a discontinuity in plant predawn water potentials, with woody plants either showing predawn water potentials reflecting exposure to saline water or exposure to freshwater. This abrupt concurrent change...

Shallow seismic reflection prospecting has been carried out in order to investigate the faults that bound to the southwest and northeast the Quaternary Upper Tiber Basin (Northern Apennines, Italy). On the northeastern margin of the basin a ??? 1 km long reflection seismic profile images a fault segment and the...

American White Pelicans (Pelecanus erythrorhynchos) that breed on Anaho Island, Pyramid Lake, Nevada, are potentially exposed to a variety of contaminants. Therefore, the reproductive success of this colony was monitored in 1996 and eggs, blood and feathers from nestlings, livers from adults and nestlings, regurgitated fish from nestlings, and fish...

The Florida Aquifer Vulnerability Assessment (FAVA) was designed to provide a tool for environmental, regulatory, resource management, and planning professionals to facilitate protection of groundwater resources from surface sources of contamination. The FAVA project implements weights-of-evidence (WofE), a data-driven, Bayesian-probabilistic model to generate a series of maps reflecting relative aquifer...

In natural flows, bed sediment particles are entrained and moved by the fluctuating forces, such as lift and drag, exerted by the overlying flow on the particles. To develop a better understanding of these forces and the relation of the forces to the local flow, the downstream and vertical components...

There are few methods available for broadly assessing microbial community metabolism directly within a groundwater environment. In this study, hydrogen consumption rates were estimated from in situ injection/withdrawal tests conducted in two geochemically varying, contaminated aquifers as an approach towards developing such a method. The hydrogen consumption first-order rates varied...

We report the concentration, phosphorus (P) and nitrogen (N) content, and size and chemical fractionation of fine suspended particles (0.2‐100 µm) and colloids (3 kilodalton [kDa]‐0.1 µm) in the surface water of Everglades wetlands along regional and P‐enrichment gradients. Total suspended sediment concentrations ranged from 0.7 to 2.7 mg L−1....