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The stability of water ice, epsomite, and hexahydrite to loss of H 2O molecules to the atmosphere at equatorial latitudes of Mars was studied to determine their potential contributions to the measured abundance of water-equivalent hydrogen (WEH). Calculation of the relative humidity based on estimates of yearly averages of water-vapor...

The toxic and carcinogenic properties of inorganic and organic arsenic species make their determination in natural water vitally important. Determination of individual inorganic and organic arsenic species is critical because the toxicology, mobility, and adsorptivity vary substantially. Several methods for the speciation of arsenic in groundwater, surface-water, and acid mine...

Oo??nopsis foliosa var. foliosa and var. monocephala are endemic to short-grass steppe of southeastern Colorado and until recently were considered geographically disjunct. The only known qualitative feature separating these 2 varieties is floral head type; var. foliosa has radiate heads, whereas var. monocephala heads are discoid. Sympatry between these varieties...

Effects of inhalation of volatilized trichloroethylene (TCE) or perchloroethylene (PCE) were assessed based on the health and population size of wild, burrowing mammals at Edwards Air Force Base (CA, USA). Organic soil-vapor concentrations were measured at three sites with aquifer contamination of TCE or PCE of 5.5 to 77 mg/L...

This chapter investigates fire as a dynamic ecosystem process by first investigating fire in the context of general ecological theory, then discussing the concept of fire regimes, and finally by developing and applying a new framework for classifying fire regimes that better allows for the understanding of the patterns of...

No abstract available at this time...

In a study conducted by the US Geological Survey and the Centers for Disease Control and Prevention, 24 water samples were collected at selected locations within a drinking-water-treatment (DWT) facility and from the two streams that serve the facility to evaluate the potential for...

No abstract available at this time...

No abstract available at this time...

The Fort Union Formation in the Williston Basin of North Dakota, South Dakota, and Montana comprises chronostratigraphic and depositional sequences of Paleocene age. Individual chronostratigraphic sequences are defined by palynostratigraphic (pollen and spore) biozones and radiometric (40Ar/39Ar) ages obtained from tonsteins or volcanic ash layers. Analyses of depositional sequences are...

Speciation of Hg and conversion to methyl-Hg were evaluated in mine wastes, sediments, and water collected from the Almade??n District, Spain, the world's largest Hg producing region. Our data for methyl-Hg, a neurotoxin hazardous to humans, are the first reported for sediment and water from the Almade??n area. Concentrations of...

No abstract available at this time...

During the 3 November 2002 Denali fault earthquake, surface rupture propagated through a small, old-growth forest in the Delta River valley and damaged many trees growing on the fault. Damage was principally the result of fault offset of tree roots and tilting of trees. Some trees were split by surface...

No abstract available....

The degree to which widespread avian blood parasites in the genera Plasmodium and Haemoproteus pose a threat to novel hosts depends in part on the degree to which they are constrained to a particular host or host family. We examined the host distribution and host-specificity of these parasites in birds...

This chapter reviews the concepts developed in the book and challenges Californians to accept the fact that they live in fire-prone ecosystems. California’s variety of fire regimes are products of its wide diversity of vegetation, climate, topography, and ignitions. The role fire plays in an ecosystem is characterized by the...

No abstract available at this time...

In 1991, Harvey Doerksen was able to write a memoir discussing 20 years of instream flow work (Doerksen 1991). He recalled coming into the field in about 1973, but points out that there were many dedicated professionals working on the front line of what has become known as the environmental...

This chapter addresses the immediately south of the Cascades in the Sierra Nevada bioregion, extending nearly half the length of the state of California. This bioregion is one of the most striking features of the state of California, extending from the southern Cascade Mountains in the north to the Tehachapi...

This chapter explores fire as a physical process, including combustion, fuel characteristics, fuel models, fire weather, ignition sources, mechanisms for fire spread, and fire effects. In wildland fuels, combustion occurs in three phases: preheating, gaseous, and smoldering. Fuel is characterized by physical and chemical properties that affect combustion and fire...

Although hoary bats (Lasiurus cinereus) are presumed to be migratory and capable of long-distance dispersal, traditional marking techniques have failed to provide direct evidence of migratory movements by individuals. We measured the stable hydrogen isotope ratios of bat hair (δDh) and determined how these values relate to stable hydrogen isotope...

Studies of reservoir sedimentation are vital to understanding scientific and management issues related to watershed sediment budgets, depositional processes, reservoir operations, and dam decommissioning. Here we quantify the mass, organic content, and grain-size distribution of a reservoir deposit in northern California by two methods of extrapolating measurements of sediment physical...

Introduced, nonnative brook trout (Salvelinus fontinalis) were removed from a mountain lake in Mount Rainier National Park, Washington, to examine the capacity of native Ambystoma gracile (Northwestern Salamander) in the lake to respond to the intentional removal of fish. Temporal trends (Δ̄N) were calculated for A. gracile larvae/neotene and...

A new and unique vegetation greenness forecast (VGF) model was designed to predict future vegetation conditions to three months through the use of current and historical climate data and satellite imagery. The VGF model is implemented through a seasonality-adjusted autoregressive distributed-lag function, based on our finding that the normalized difference...

Thirty interferometric synthetic aperture radar (InSAR) images, spanning various intervals during 1992–2000, document coeruptive and posteruptive deformation of the 1992–1993 eruption on Seguam Island, Alaska. A procedure that combines standard damped least squares inverse methods and collective surfaces, identifies three dominant amorphous clusters of deformation point sources. Predictions generated from...