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Recent literature on the diffusion of innovations concentrates either specifically on public adoption of policy, where social or environmental conditions are the dependent variables for adoption, or on private adoption of an innovation, where emphasis is placed on the characteristics of the innovation itself. This article uses both the policy...

Stream ecologists often use enclosure experiments to investigate predator-prey interactions and competition within and among fish species. The design of enclosures, manipulation of species densities, and method of replication may influence experimental results. We designed an experiment with enclosure cages (1 m2, 6-mm mesh) to examine the relative influence of...

Compositional and age data from offshore pillow lavas and volcaniclastic sediments, along with on-land geologic, seismic, and deformation data, provide broad perspectives on the early growth of Kilauea Volcano and the long-term geometric evolution of its rift zones. Sulfur-rich glass rinds on pillow lavas and volcaniclastic sediments derived from...

Event-response coring on the Po River prodelta (northern Adriatic Sea) coupled with shipboard digital X-radiography, resistivity profiling, and grain-size analyses permitted documentation of the initial distribution and physical properties of the October 2000 flood deposit. The digital X-radiography system comprises a constant-potential X-ray source and an amorphous silicon imager with...

Two practical approaches incorporating lithologic information for groundwater modeling calibration are presented to estimate distributed, cell-based hydraulic conductivity. The first approach is to estimate optimal hydraulic conductivities for geological materials by incorporating thickness distribution of materials into inverse modeling. In the second approach, residuals for the groundwater model solution are...

With funding from the George Mitchell Center for the Environment at the University of Maine, a team of scientists used a simple laboratory-based sediment resuspension design, and two well-established aquatic toxicology models, fathead minnows (Pimephales promelas) and zebrafish (Danio rerio), to evaluate if resuspension of Penobscot river sediment significantly elevates...

Analysis of strong-motion instrument recordings in Seattle, Washington, resulting from the 2002 Mw 7.9 Denali, Alaska, earthquake reveals that amplification in the 0.2-to 1.0-Hz frequency band is largely governed by the shallow sediments both inside and outside the sedimentary basins beneath the Puget Lowland. Sites above the deep sedimentary strata...

The Mars Exploration Rovers investigated numerous craters in Gusev crater and Meridiani Planum during the first ???400 sols of their missions. Craters vary in size and preservation state but are mostly due to secondary impacts at Gusev and primary impacts at Meridiani. Craters at both locations are modified primarily by...

By sol 440, the Spirit rover has traversed a distance of 3.76 km (actual distance traveled instead of odometry). Localization of the lander and the rover along the traverse has been successfully performed at the Gusev crater landing site. We localized the lander in the Gusev crater using two-way Doppler...

Oil-prone marine petroleum source rocks contain type I or type II kerogen having Rock-Eval pyrolysis hydrogen indices greater than 600 or 300-600 mg hydrocarbon/g total organic carbon (HI, mg HC/g TOC), respectively. Samples from 29 marine source rocks worldwide that contain mainly type II kerogen (HI = 230-786 mg HC/g...

Red-tailed Hawks (Buteo jamaicensis) have expanded their range as trees have invaded formerly-open grasslands. Desert grasslands of southern Arizona have been invaded by mesquite trees (Prosopis velutina) since Anglo-American settlement and now support a large population of Red-tailed Hawks. We studied a population of Red-tailed Hawks in an altered desert...

Seismic velocity parameters in limited, but heterogeneous volumes can be inferred using a double-difference tomographic algorithm, but to obtain meaningful results accuracy must be maintained at every step of the computation. MONTEILLER et al. (2005) have devised a double-difference tomographic algorithm that takes full advantage of the accuracy of cross-spectral...

Submarine alkalic and transitional basalts collected by submersible along Kilauea volcano's south flank represent early eruptive products from Earth's most active volcano. Strongly alkalic basalt fragments sampled from volcaniclastic deposits below the mid-slope Hilina Bench yield 40Ar/39Ar ages from 212 ± 38 to 280 ± 20 ka. These ages are similar to high-precision 234 ± 9 and...

We analyzed RADARSAT-1 synthetic aperture radar (SAR) data to compute interferometric SAR (InSAR) images of surface deformation at Uzon caldera, Kamchatka, Russia. From 2000 to 2003 approximately 0.15 m of inflation occurred at Uzon caldera, extending beneath adjacent Kikhpinych volcano. This contrasts with InSAR data showing no significant deformation during...

Myxobolus cerebralis, the parasite that causes salmonid whirling disease, has had detrimental effects on several salmonid populations in the Intermountain West, including the rainbow trout in the Madison River, Montana, USA. The goal of this study was to examine relationships among characteristics of the environment, Tubifex tubifex (the alternate host)...

Some 30 y after wolves (Canis lupus) were implicated in decimating wintering white-tailed deer (Odocoileus virginianus) in a 3000-km2 area of northeastern Minnesota, wintering deer still have not recolonized the area. From 1976 to 2004, we aerially radio-tracked wolves there during 250 h and recorded 2 deer (in 1985...

The motion of a building depends on the excitation, the coupling of the building to the ground, and the mechanical properties of the building. We separate the building response from the excitation and the ground coupling by deconvolving the motion recorded at different levels in the building and apply this...

In this study, we conducted rainfall simulation experiments in a cool desert ecosystem to examine the role of biological soil crust disturbance and composition on dissolved and sediment C and N losses. We compared runoff and sediment C and N losses from intact late-successional dark cyanolichen crusts (intact) to both...

Two manned submersible dives examined the Hualalai Northwest rift zone and an elongate ridge cresting at 3900 mbsl during a 2002 JAMSTEC cruise. The rift zone flank at dive site S690 (water depth 3412–2104 m) is draped by elongated and truncated pillow lavas. These olivine-rich tholeiitic lavas are compositionally...

Changes in the water-surface area occupied by the Cuitzeo Lake, Mexico, during the 1974-2001 period are analysed in this study. The research is based on remote sensing and geographic information techniques, as well as statistical analysis. High-resolution satellite image data were used to analyse the 1974-2000 period, and very low-resolution...

Water quality and criculation in Florida Bay (a shallow, subtropical estuary in south Florida) are highly dependent upon the development and evolution of carbonate mud banks distributed throughout the Bay. Predicting the effect of natural and anthropogenic perturbations on carbonate sedimentation requires an understanding of annual,...

To investigate the potential for the geologic storage of CO2 in saline sedimentary aquifers, 1600??ton of CO2 were injected at ???1500 m depth into a 24-m sandstone section of the Frio Formation - a regional reservoir in the US Gulf Coast. Fluid samples obtained from the injection and observation wells...

According to the United States Geological Survey (USGS), Idaho's preliminary nonfuel mineral production value jumped to $893 million in 2005. Principal minerals by value included molybdenum concentrates, phosphate rock, sand and gravel, silver and portland cement. The state ranked second in phosphate and garnet production, third in silver and pumice,...

Fires create and consume snags (standing dead trees), an important structural and ecological component of ponderosa pine forests. The effects of repeated fires on snag densities in ponderosa pine forests of the southwestern USA have not been studied. Line intercept sampling was used to estimate snag densities in areas of...

Macro- and molecular-scale knowledge of uranyl (U(VI)) partitioning reactions with soil/sediment mineral components is important in predicting U(VI) transport processes in the vadose zone and aquifers. In this study, U(VI) reactivity and surface speciation on a poorly crystalline aluminosilicate mineral, synthetic imogolite, were...