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Water from the San Joaquin Delta, having chloride concentrations up to 3590 mg/L, has intruded fresh water aquifers underlying Stockton, California. Changes in chloride concentrations at depth within these aquifers were evaluated using sequential electromagnetic (EM) induction logs collected during 2004 through 2007 at seven multiple-well sites as deep as...

The Hakalau Forest Unit of the Big Island National Wildlife Refuge Complex has intensively managed feral pigs (Sus scrofa) and monitored feral pig presence with surveys of all managed areas since 1988. Results of all available data regarding pig management activities through 2004 were compiled and analyzed, but no further...

Because of its role in many ecological processes, movement of animals in response to landscape features is an important subject in ecology and conservation biology. In this paper, we develop models of animal movement in relation to objects or fields in a landscape. We take a finite mixture modeling approach...

Desertification, the broad-scale conversion of perennial grasslands to dominance by annuals or xerophytic shrubs, has affected drylands globally over the past several centuries. Desertification is a cumulative threat that includes both climatic (e.g., drought) and land-use drivers (e.g., livestock overgrazing, fire). In this chapter, we determine the vulnerability of different...

Interspecies interactions can affect how species are distributed, put constraints on habitat expansion, and reduce the fundamental niche of the affected species. Using logistic regression, we analyzed and compared 174 Tamias palmeri and 94 Tamias panamintinus within an isolated mountain range of the Basin and Range Province of southern Nevada....

Landmark legislation provides guiding principles for land management planning in southern Nevada and the rest of the United States. Such legislation includes, but is not limited to, the Forest Service Organic Administration Act of 1897 (16 U.S>C. 473-478, 479-482 and 551), National Park Service Organic Act of 1916 (U.S.C. Title...

Wind erosion and aeolian transport processes are under studied compared to rainfall-induced erosion and sediment transport on burned landscapes. Post-fire wind erosion studies have predominantly focused on near-surface sediment transport and associated impacts such as on-site soil loss and site fertility. Downwind impacts, including air quality degradation and deposition of dust or...

The ability to successfully colonize and persist in diverse environments likely requires broad morphological and behavioral plasticity and adaptability, and this may partly explain why the Peregrine Falcon (Falco peregrinus) exhibits a large range of morphological characteristics across their global distribution. Regional and local differences within Peregrine Falcons were sufficiently...

Mallards (Anas platyrhynchos) have been observed foraging on intertidal Pacific sand crabs (Hippidae, Emerita analoga) in the swash zone of sandy beaches around Coal Oil Point Reserve, California, and several other beaches on the west coast since at least November 2010. Unlike foraging shorebirds, Mallards do not avoid incoming swashes....

Chemometric analyses of geochemical data for 165 crude oil samples from the San Joaquin Basin identify genetically distinct oil families and their inferred source rocks and provide insight into migration pathways, reservoir compartments, and filling histories. In the first part of the study, 17 source-related biomarker and stable carbon-isotope ratios...

Photographic imaging is the oldest form of remote sensing used in coral reef studies. This chapter briefly explores the history of photography from the 1850s to the present, and delves into its application for coral reef research. The investigation focuses on both photographs collected from low-altitude fixed-wing and rotary aircraft,...

Herbivory has played a major role in dictating vegetation abundance and species composition at Kingman Marsh in Anacostia Park, Washington, D.C., since restoration of this tidal freshwater wetland was initiated in 2000. The diverse and robust vegetative cover that developed in the first year post-reconstruction experienced significant decimation in...

The ecology of mosquito vectors and malaria parasites affect the incidence, seasonal transmission and geographical range of malaria. Most malaria models to date assume constant or linear responses of mosquito and parasite life-history traits to temperature, predicting optimal transmission at 31 °C. These models are at odds with field observations...

The Southern Oregon-Northeastern California (SONEC) region is an important migration and breeding area for Pacific Flyway waterfowl. Through a Conservation Effects Assessment Project (CEAP) partnership, the Intermountain West Joint Venture conducted a preliminary analysis of the contribution of SONEC Wetlands Reserve Program (WRP) enrollments in meeting recently established spring migrating waterfowl...

As part of the assessment of undiscovered oil and gas resources in Jurassic and Cretaceous strata of the U.S. Gulf Coast in 2010, the U.S. Geological Survey assessed carbonate rocks of the Fredericksburg and Washita groups and their equivalent units underlying onshore lands and State waters. One conventional assessment unit...

In 1995, U.S. Geological Survey made the first systematic assessment of the volume of natural gas stored in the hydrate accumulations of the United States. That study, along with numerous other studies, has shown that the amount of gas stored as methane hydrates in the world greatly exceeds the volume...

The invasive yellow bluestem (Bothriochloa ischaemum [L.] Keng) threatens native biodiversity, and its control is of interest to land managers involved in restoration of invaded grasslands. We used single, double, and triple applications of glyphosate (2.125 kg ai.ha-1.application-1) over the course of one growing season in combinations at different timings...

We investigated the influence of Old World bluestem (Bothriochloa ischaemum; OWB) monocultures on grassland bird abundance through analysis of vegetation structure and food availability. We compared breeding bird density, vegetation structure and composition, and arthropod biomass between six native grass and six OWB fields in the southern Great Plains. The...

Managers in southern Nevada are challenge with determining appropriate goals and objectives and developing viable approaches for maintaining and restoring sustainable ecosystems in a time of rapid socio-ecological and environmental change. Sustainable or "healthy" ecosystems supply clean air, water and habitat for a diverse array of plants and animals. As...

The International Seismological Centre–Global Earthquake Model (ISC–GEM) Global Instrumental Earthquake Catalogue (1900–2009) is the result of a special effort to substantially extend and improve currently existing global catalogs to serve the requirements of specific user groups who assess and model seismic hazard and risk. The data from the ISC–GEM Catalogue...

This document describes progress to date on the development of a harvest‐management strategy for maintaining pink‐footed goose abundance near their target level by providing for sustainable harvests in Norway and Denmark. Many goose populations in western Europe have increased dramatically in recent decades. The Svalbard population of pink‐footed geese (Anser brachyrhynchus) is a good...

Dissolved organic carbon (DOC) flux from the Penobscot River and its major tributaries in Maine was determined using continuous discharge measurements, discrete water sampling, and the LOADEST regression software. The average daily flux during 2004–2007 was 71 kg C ha−1 yr−1 (392 Mt C d−1), an amount larger than measured...

The economic vitality and quality of life of many northern Wisconsin communities is closely associated with the ecological condition of the abundant water resources in the region. Climate change models predict warmer temperatures, changes to precipitation patterns, and increased evapotranspiration in the Great Lakes region. Recently (1950-2006), many regions of...

Habitat connectivity is vital to the persistence of migratory fishes. Native tropical island stream fish assemblages composed of diadromous species require intact corridors between ocean and riverine habitats. High dams block fish migration, but low-head artificial barriers are more widespread and are rarely assessed for impacts. Among all 46 drainages...

Using classical molecular dynamics simulations, the 2D infrared (IR) spectroscopy of CN− solvated in D2O is investigated. Depending on the force field parametrizations, most of which are based on multipolar interactions for the CN− molecule, the frequency-frequency correlation function and observables computed from it differ. Most notably, models based on...