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Characterizing properties of the rock matrix that control retention and release of chlorinated solvents is essential in evaluating the extent of contamination and the application of remediation technologies in fractured rock. Core samples from seven closely spaced boreholes in a mudstone subject to trichloroethene (TCE) contamination were analyzed using Mercury...

The occurrence of birds in a survey unit is partly determined by the habitat present. Moreover, some bird species preferentially avoid some land cover types and are attracted to others. As such, land cover composition within the 400 m survey areas along a Breeding Bird Survey (BBS) route clearly influences...

Differential climate-induced shifts in phenology can create mismatches between predators and prey, but few studies have examined predator–prey mismatch across multiple life-history stages. We used long-term data from a warming stream with shifting salmonid migration timings to quantify intra-annual migration synchrony between predatory Dolly Varden (Salvelinus malma) and Pacific salmon...

Since the GEOSUR Program launched in 2007, the U.S. Geological Survey (USGS) Earth Resources Observation and Science (EROS) Center has had the honor of collaborating with CAF, PAIGH, and others supporting the Latin America GEOSUR Program. The catalyst for starting the program was the convergence of regional geospatial activities USGS,...

Postwildfire debris flows are frequently triggered by runoff following high-intensity rainfall, but the physical mechanisms by which water-dominated flows transition to debris flows are poorly understood relative to debris flow initiation from shallow landslides. In this study, we combined a numerical model with high-resolution hydrologic and geomorphic data sets to...

Upper Klamath Lake (UKL) in southern Oregon has experienced declines in water quality due to excessive nutrient loading. This has led to annual cyanobacterial blooms, primarily of Aphanizomenon flos-aquae (AFA). Benthic invertebrates are important food resources for benthic feeding fishes; however, they can increase autochthonous nutrient cycling in lakes and as a...

Global mercury contamination largely results from direct primary atmospheric and secondary legacy emissions, which can be deposited to ecosystems, converted to methylmercury, and bioaccumulated along food chains. We examined organic horizon soil samples collected across an elevational gradient on Whiteface Mountain in the Adirondack region of New York State, USA...

Residuals between ground‐motion data and ground‐motion prediction equations (GMPEs) can be decomposed into terms representing earthquake source, path, and site effects. These terms can be cast in terms of repeatable (epistemic) residuals and the random (aleatory) components. Identifying the repeatable residuals leads to a GMPE with reduced uncertainty for a...

The Pacific Northwest region of the United States provides world-class and historically important examples of a wide variety of volcanic features. This guide is designed to give a broad overview of the region’s diverse volcanism rather than focusing on the results of detailed studies; the reader should consult the...

Contamination of groundwater by enteric pathogens has commonly been associated with disease outbreaks. Proper management and treatment of pathogen sources are important prerequisites for preventing groundwater contamination. However, non-point sources of pathogen contamination are frequently difficult to identify, and existing approaches for pathogen detection are costly and only provide semi-quantitative...

Hawaiian coastal vegetation is comprised of plant species that are adapted to growing in extremely harsh conditions (salt spray, wave wash, wind, and substrates with limited nutrients) found in this habitat zone. Prior to human colonization of Hawai‘i coastal vegetation extended as a continuous ring around each of the islands,...

No abstract available....

Body condition is a gauge of the energy stores of an animal, and though it has important implications for fitness, survival, competition, and disease, it is difficult to measure directly. Instead, body condition is frequently estimated as a body condition index (BCI) using length and mass measurements. A desirable BCI...

Within the Desert Renewable Energy Conservation Plan area, which encompasses California’s Mojave Desert, development and operation of renewable energy facilities has the potential to impact golden eagle (Aquila chrysaetos) populations through loss of habitat and prey base. Developing an effective conservation strategy that aims to mitigate for such operations is necessary to...

Burbot, Lota lota (Linnaeus), is a regionally popular sportfish in the Wind River drainage of Wyoming, USA, at the southern boundary of the range of the species. Recent declines in burbot abundances were hypothesised to be caused by overexploitation, entrainment in irrigation canals and habitat loss. This study addressed the overexploitation hypothesis...

The framework presented herein supports a changing paradigm in the approaches used by coastal researchers, engineers, and social scientists to model the impacts of climate change and sea level rise (SLR) in particular along low-gradient coastal landscapes. Use of a System of Systems (SoS) approach to the coastal dynamics of...

Geoelectric fields at the Earth's surface caused by magnetic storms constitute a hazard to the operation of electric power grids and related infrastructure. The ability to estimate these geoelectric fields in close to real time and provide local predictions would better equip the industry to mitigate negative impacts on their...

Potential biological removal (PBR) is an approach used to calculate sustainable harvest and “take” limits for populations. PBR was originally derived assuming logistic growth while ignoring the effects of small population size (i.e., an Allee effect). We derived a version of PBR that includes an Allee effect (i.e., small population...

Poor developmental conditions can have long-lasting negative effects on offspring phenotypes, but impacts often differ among species. Contrasting responses may reflect disparities in experimental protocols among single-species studies or inherent differences among species in their sensitivity to early conditions and/or ability to mitigate negative impacts. We used a common experimental...

Tectonic stress in the crust evolves during a seismic cycle, with slow stress accumulation over interseismic periods, episodic stress steps at the time of earthquakes, and transient stress readjustment during a postseismic period that may last months to years. Static stress transfer to surrounding faults has been well documented to...

Manatees are a vulnerable, charismatic sentinel species from the evolutionarily divergent Afrotheria. Manatee health and resistance to infectious disease is of great concern to conservation groups, but little is known about their immune system. To develop manatee-specific tools for monitoring health, we first must have a general knowledge of how...

We investigated the relation between environmental mercury exposure and corticosterone concentrations in free-living adult common loons (Gavia immer). We determined blood and feather mercury concentrations and compared them to testosterone, estradiol, and stress-induced plasma corticosterone concentrations. Although neither testosterone nor estradiol correlated with Hg levels, there was a robust positive...

The increase of tree density in forests of the American Southwest promotes extreme fire events, understory biodiversity losses, and degraded habitat conditions for many wildlife species. To ameliorate these changes, managers and scientists have begun planning treatments aimed at reducing fuels and increasing understory biodiversity. However, spatial variability in tree...

Whitebark pine and foxtail pine serve foundational roles in the subalpine zone of the Sierra Nevada. They provide the dominant structure in tree-line forests and regulate key ecosystem processes and community dynamics. Climate change models suggest that there will be changes in temperature regimes and in the timing and magnitude...

The timing and drivers of vegetation dynamics and formation of no-analog plant communities during the last deglaciation in the unglaciated southeastern US are poorly understood. We present a multi-proxy record spanning the past 19,800 years from Cupola Pond in the Ozarks Mountains, consisting of replicate high-resolution pollen records, 25 AMS...