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Application of the cross-borehole flow method, in which short pumping cycles in one borehole are used to induce time-transient flow in another borehole, demonstrated that a simple hydraulic model can characterize the fracture connections in the bedrock mass between the two boreholes. The analysis determines the properties of fracture connections...

1. Markov chain Monte Carlo (MCMC) is a simulation technique that has revolutionised the analysis of ecological data, allowing the fitting of complex models in a Bayesian framework. Since 2001, there have been nearly 200 papers using MCMC in publications of the Ecological Society of America and the British Ecological...

This report reviews the geological basis for some recent estimates of earthquake hazards in the Cascadia region between southern British Columbia and northern California. The largest earthquakes to which the region is prone are in the range of magnitude 8-9. The source of these great earthquakes is the fault down...

Aquatic invasive species pose major ecological and economic threats to aquatic ecosystems worldwide via displacement, predation, or hybridization with native species and the alteration of aquatic habitats and hydrologic cycles. Modeling the habitat suitability of alien aquatic species through spatially explicit mapping is an increasingly important risk assessment tool. Habitat...

The Mosier area lies along the Columbia River in northwestern Wasco County between the cities of Hood River and The Dalles, Oregon. Major water uses in the area are irrigation, municipal supply for the city of Mosier, and domestic supply for rural residents. The primary source of water is groundwater...

Salt marshes are delicate landforms at the boundary between the sea and land. These ecosystems support a diverse biota that modifies the erosive characteristics of the substrate and mediates sediment transport processes. Here we present a broad overview of recent numerical models that quantify the formation and evolution of salt...

Climate change challenges many of the basic assumptions routinely used by conservation planners and managers, including the identification and prioritization of areas for conservation based on current environmental conditions and the assumption those conditions could be controlled by management actions. Climate change will likely alter important ecosystem drivers (temperature, precipitation,...

The movement and migration pattern of the 'Near Threatened' Sooty Falcon Falco concolor is poorly known. Sooty Falcons breed on the islands of the Arabian Gulf after arriving from their non-breeding areas that are mainly in Madagascar. In the first satellite tracking of the species we fitted a 9.5 g...

Higher atmospheric concentrations of CO2 can offset the negative effects of flooding or salinity on plant species, but previous studies have focused on mature, rather than regenerating vegetation. This study examined how interacting environments of CO2, water regime, and salinity affect seed germination and seedling biomass of floating freshwater marshes...

We introduce Cost Distance FISHeries (CDFISH), a simulator of population genetics and connectivity in complex riverscapes for a wide range of environmental scenarios of aquatic organisms. The spatially-explicit program implements individual-based genetic modeling with Mendelian inheritance and k-allele mutation on a riverscape with resistance to movement. The program simulates individuals...

This report documents the development of Global Earthquake Model (GEM) Basic Building Taxonomy and it also provides version 1.0 of this Taxonomy for its immediate application within GEM Physical Risk projects. Criteria for development of the GEM Building Taxonomy required that the Taxonomy be relevant to seismic performance of different construction types; be...

Iron oxyhydroxide, goethite (α-FeOOH), was evaluated as a potential formation mineral reactant for trapping CO2 in a mineral phase such as siderite (FeCO3), when a mixture of CO2-SO 2 flue gas is injected into a saline aquifer. Two thermodynamic simulations were conducted, equilibrating a CO2-SO2 fluid mixture with a NaCl-brine...

We present an approach based on geomorphometry to predict material properties and characterize site conditions using the VS30 parameter (time‐averaged shear‐wave velocity to a depth of 30 m). Our framework consists of an automated terrain classification scheme based on taxonomic criteria (slope gradient, local convexity, and surface texture) that systematically identifies 16 terrain...

Issues with ecological data (e.g. non-normality of errors, nonlinear relationships and autocorrelation of variables) and modelling (e.g. overfitting, variable selection and prediction) complicate regression analyses in ecology. Flexible models, such as generalized additive models (GAMs), can address data issues, and machine learning techniques (e.g. gradient boosting) can help resolve modelling...

Seismicity in the New Madrid seismic zone (NMSZ) of the central United States is generally attributed to a stepover structure in which the Reelfoot thrust fault transfers slip between parallel strike-slip faults. However, some arms of the seismic zone do not fit this simple model. Comparison of the NMSZ with...

Data from large-scale debris-flow experiments are combined with modeling of particle-size segregation to explain the formation of lateral levees enriched in coarse grains. The experimental flows consisted of 10 m3 of water-saturated sand and gravel, which traveled ∼80 m down a steeply inclined flume before forming an elongated leveed deposit 10 m...

Lesser scaup (Aythya affinis [Eyton]) populations remain below their long-term average despite improved habitat conditions along spring migration routes and at breeding grounds. Scaup are typically associated with large, semipermanent wetlands and exhibit regional preferences along migration routes. Identifying consistently used habitats for conservation and restoration is complicated by irregular wetland...

We examined mercury exposure in 133 endangered California clapper rails (Rallus longirostris obsoletus) within tidal marsh habitats of San Francisco Bay, California from 2006 to 2010. Mean total mercury concentrations were 0.56 μg/g ww in blood (range: 0.15–1.43), 9.87 μg/g fw in head feathers (3.37–22.0), 9.04 μg/g fw in breast...

Environmental age tracers have been used in various ways to help assess vulnerability of drinking-water production wells to contamination. The most appropriate approach will depend on the information that is available and that which is desired. To understand how the well will respond to changing nonpoint-source contaminant inputs at the...

A positive relationship between interannual sea level and plant growth is thought to stabilize many coastal landforms responding to accelerating rates of sea level rise. Numerical models of delta growth, tidal channel network evolution, and ecosystem resilience incorporate a hump-shaped relationship between inundation and plant primary production, where vegetation growth...

Changes in land use, land cover, disturbance regimes, and land management have considerable influence on carbon and greenhouse gas (GHG) fluxes within ecosystems. Through targeted land-use and land-management activities, ecosystems can be managed to enhance carbon sequestration and mitigate fluxes of other GHGs. National-scale, comprehensive analyses of carbon sequestration potential...

The surficial geologic map shows the distribution of nonlithified earth materials at land surface in an area of 23 7.5-minute quadrangles (919 mi2 total) in southeastern Massachusetts. Across Massachusetts, these materials range from a few feet to more than 500 ft in thickness. They overlie bedrock, which crops out in...

AquaPathogen X is a template database for recording information on individual isolates of aquatic pathogens and is available for download from the U.S. Geological Survey (USGS) Western Fisheries Research Center (WFRC) website (http://wfrc.usgs.gov). This template database can accommodate the nucleotide sequence data generated in molecular epidemiological studies along with the...

Massachusetts, New Jersey, Connecticut, and Maine have adopted regulatory zones around seasonal (vernal) pools to conserve terrestrial habitat for pool-breeding amphibians. Most amphibians require access to distinct seasonal habitats in both terrestrial and aquatic ecosystems because of their complex life histories. These habitat requirements make them particularly vulnerable to land...

In December 2005, the U.S. Geological Survey (USGS), in cooperation with the City of Houston, Texas, began collecting discrete water-quality samples for nutrients, total organic carbon, bacteria (Escherichia coli and total coliform), atrazine, and suspended sediment at two USGS streamflow-gaging stations that represent watersheds contributing to Lake Houston (08068500 Spring...