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It is generally recognized that meeting society's emerging environmental science and management needs will require the marine data community to provide simpler, more effective and more interoperable access to its data. There is broad agreement, as well, that data standards are the bedrock upon which interoperability will be built. The...

Tropical forest destruction and fragmentation of habitat patches may reduce population persistence at the landscape level. Given the complex nature of simultaneously evaluating the effects of these factors on biotic populations, statistical presence/absence modelling has become an important tool in conservation biology. This study uses logistic regression to evaluate the...

We report estimates of mercury (Hg) flux to the sediments of Lake Tahoe, California–Nevada: 2 and 15–20 µg/m2/year in preindustrial and modern sediments, respectively. These values result in a modern to preindustrial flux ratio of 7.5–10, which is similar to flux ratios recently reported for other alpine lakes in California, and...

No abstract available....

Nesting belted kingfishers (hereafter kingfishers, Ceryle alcyon) were studied on the Hudson River near Fort Edward south to New Baltimore (NY, USA) and three nearby river drainages in 2004. Concentrations of 28 organochlorine pesticides, 160 polychlorinated biphenyl (PCB) congeners, and 17 dioxin and furan (PCDD‐F) congeners were quantified in kingfisher eggs....

The combined effect of salinity and temperature on density-driven convection was evaluated in this study for a large (28 km2) cooling canal system (CCS) at a thermoelectric power plant in south Florida, USA. A two-dimensional cross-section model was used to evaluate the effects of hydraulic heterogeneities, cooling canal salinity, heat transport,...

Chemical weathering of silicate minerals has long been known as a sink for atmospheric CO2, and feedbacks between weathering and climate are believed to affect global climate. While warmer temperatures are believed to increase rates of weathering, weathering in cool climates can be accelerated by increased mineral exposure due...

Regional land-use models must address several foundational elements, including understanding geographic setting, establishing regional land-use histories, modeling process and representing drivers of change, representing local land-use patterns, managing issues of scale and complexity, and development of scenarios. Key difficulties include managing an array of biophysical and socioeconomic processes across multiple...

Two-dimensional hydrodynamic models are now widely used in aquatic habitat studies. To test the sensitivity of calculated habitat outcomes to limitations of such a model and of typical field data, bathmetry, depth and velocity data were collected for three discharges in the vicinity of two large boulders in the...

This report contains spatial datasets of natural and anthropogenic features and spatial datasets detailing surface-water, ground-water, and other types of environmental information collected in and surrounding Kickapoo Tribal Lands. Spatial datasets were compiled from Federal and Oklahoma State agencies. Surface-water, ground-water, and other types of environmental information of natural and...

Land cover and land use changes can have a wide variety of ecological effects, including significant impacts on soils and water quality. In rural areas, even subtle changes in farming practices can affect landscape features and functions, and consequently the environment. Fine-scale analyses have to be performed to better understand...

Unsaturated zone N fate and transport were evaluated at four sites to identify the predominant pathways of N cycling: an almond [Prunus dulcis (Mill.) D.A. Webb] orchard and cornfield (Zea mays L.) in the lower Merced River study basin, California; and corn–soybean [Glycine max (L.) Merr.] rotations in study basins...

Interferometric synthetic aperture radar (InSAR) provides an all-weather imaging capability for measuring ground-surface deformation and inferring changes in land surface characteristics. InSAR enables scientists to monitor and characterize hazards posed by volcanic, seismic, and hydrogeologic processes, by landslides and wildfires, and by human activities such as mining and fluid extraction...

The geologic map of Lassen Volcanic National Park (LVNP) and vicinity encompasses 1,905 km2 at the south end of the Cascade Range in Shasta, Lassen, Tehama, and Plumas Counties, northeastern California (fig. 1, sheet 3). The park includes 430 km2 of scenic volcanic features, glacially sculpted terrain, and the most...

This set of programs simulates steady-state stream temperatures throughout a dendritic stream network handling multiple time periods per year. The software requires a math co-processor and 384K RAM. Also included is a program (SSTEMP) designed to predict the steady state stream temperature within a single stream segment for a single...

Habitat modeling is an important tool used to simulate the potential distribution of a species for a variety of basic and applied questions. The desert tortoise (Gopherus agassizii) is a federally listed threatened species in the Mojave Desert and parts of the Sonoran Desert of California, Nevada, Utah, and Arizona....

Fishery-independent (FI) surveys provide critical information used for the sustainable management and conservation of fish populations. Because fisheries management often requires the effects of management actions to be evaluated and detected within a relatively short time frame, it is important that research be directed toward FI survey evaluation, especially with...

Understanding how sandy beaches respond to storms is critical for effective sediment management and developing successful erosion mitigation efforts. However, only limited progress has been made in relating observed beach changes to wave conditions, with one of the major limiting factors being the lack of temporally dense beach topography and...

[1] In coming decades, higher annual temperatures, increased growing season length, and increased dormant season precipitation are expected across the northeastern United States in response to anthropogenic forcing of global climate. We synthesized long-term stream hydrochemical data from the Sleepers River Research Watershed in Vermont, United States, to explore the...

Shoreface nourishment can be an efficient technique to feed sediment into the littoral zone without the order of magnitude cost increase incurred by directly nourishing the beach. An erosion hot spot at Ocean Beach in San Francisco, California, USA, threatens valuable public infrastructure as well as safe recreational use of...

he apparent settling velocity (Vs) is a term used in empirical, steady-state, mass-balance lake models to represent the net phosphorus flux from the water column. The Vollenweider (1969) mixed-reactor lake model was rearranged and used to calculate Vs values for total phosphorus (TP) for three lakes treated with alum to...

The diffusion equation is one of the three great partial differential equations of classical physics. It describes the flow or diffusion of heat in the presence of temperature gradients, fluid flow in porous media in the presence of pressure gradients, and the diffusion of molecules in the presence of chemical...

Fishery biologists spend considerable effort over multiple years collecting data on fish population and community status using a particular sampling method or set of methods. However, new (and often more effective) sampling methods and technologies are continuously being developed. To incorporate these new sampling techniques, fishery biologists need a means...

We review twentieth century and projected twenty-first century changes in climatic and hydrologic conditions in the northeastern United States and the implications of these changes for forest ecosystems. Climate warming and increases in precipitation and associated changes in snow and hydrologic regimes have been observed over the last century, with...

We assessed the potential for reestablishing elk (Cervus elaphus) in Great Smoky Mountains National Park (GSMNP), USA, by estimating vital rates of experimentally released animals from 2001 to 2006. Annual survival rates for calves ranged from 0.333 to 1.0 and averaged 0.592. Annual survival for subadult and adult elk (i.e.,...