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Using the Mars Exploration Rover Opportunity, we have compiled one of the first field geologic maps on Mars while traversing the Noachian terrain along the rim of the 22 km diameter Endeavour Crater (Latitude −2°16′33″, Longitude −5°10′51″). In situ mapping of the petrographic, elemental, structural, and stratigraphic characteristics of outcrops and rocks...

For almost a century the Baja California peninsula (Peninsula), Gulf of California (Gulf), and broader Sonoran Desert region (figure 1) have drawn geologists and biologists alike to study its unique physical and evolutionary processes (e.g., Wittich 1920; Darton 1921; Nelson 1921; Johnston 1924; Beal 1948; Durham and Allison 1960). The...

In the past, hydrologic modeling of surface water resources has mainly focused on simulating the hydrologic cycle at local to regional catchment modeling domains. There now exists a level of maturity among the catchment, global water security, and land surface modeling communities such that these communities are converging toward continental...

The sea lamprey, Petromyzon marinus, is emerging as a model organism for understanding how pheromones can be used for manipulating vertebrate behavior in an integrated pest management program. In a previous study, a synthetic sex pheromone component 7α,12α, 24-trihydroxy-5α-cholan-3-one 24-sulfate (3kPZS) was applied to sea lamprey traps in eight...

BackgroundWe hypothesize that invasive English ivy (Hedera helix) harbors endophytic microbes that promote plant growth and survival. To evaluate this hypothesis, we examined endophytic bacteria in English ivy and evaluated effects on the host plant.MethodsEndophytic bacteria were isolated...

We evaluated the ecosystem regime shift in the main basin of Lake Huron that was indicated by the 2003 collapse of alewives, and dramatic declines in Chinook salmon abundance thereafter. We found that the period of 1995-2002 should be considered as the early phase of the final regime shift. We...

In California, sea-level rise during the 21st century threatens to accelerate coastal cliff recession rates. To forecast such changes for managers and policymakers, models must play a key role. In this paper, we extend a ~70-year long dataset of measured historic sea cliff retreat rates in Southern California into the 21st century...

Edge effects on nesting success have been documented in breeding birds in a variety of contexts, but there is still uncertainty in how edge type and spatial scale determine the magnitude and detectability of edge effects. Habitat edges are often viewed as predator corridors that surround or penetrate core habitat...

No abstract available....

A controlled vocabulary for the National Hydrography Dataset (NHD) of the United States was developed as Linked Open Data (LOD). The vocabulary has two main parts: a glossary and a set of triples reflecting the NHD data model as it is organized in geographic information systems (GIS). The glossary consists...

Large bottom roughness is a characteristic of most coral reef environments and this has been shown to have a substantial impact on hydrodynamic processes in these environments. In this paper, we evaluate suspended sediment concentration (SSC) data as well detailed hydrodynamic data over a coral reef flat in Ningaloo Reef,...

The U.S. Geological Survey, in cooperation with the Town of Framingham, Massachusetts, has investigated the potential of proposed groundwater withdrawals at the Birch Road well site to affect nearby surface water bodies and wetlands, including Lake Cochituate, the Sudbury River, and the Great Meadows National Wildlife Refuge in east-central Massachusetts....

No abstract available....

Obtaining calibration data for models depicting conditions during pre-development periods can be challenging as such periods are characteristically data poor. This study presents two examples where simulation of historic water conveyance structures were used to help characterize historic, or pre-modern, conditions in calibration of groundwater flow models. Persian water...

Woodland ponds are important landscape features that help sustain populations of amphibians that require this aquatic habitat for successful reproduction. Species abundance patterns often reflect site-specific differences in hydrology, physical characteristics, and surrounding vegetation. Large-scale processes such as changing land cover and environmental conditions are other potential drivers influencing amphibian...

High spatial resolution textural (scanning electron microscope (SEM)), chemical (electron microprobe (EMP)) and laser ablation-inductively coupled plasma-mass spec- trometry (LA-ICP-MS)), and sulfur isotopic (secondary ion mass spectrometry (SIMS)) analyses of pyrite from the Qiuling sediment-hosted gold deposit (232±4 Ma) in the West Qinling orogen, central China were conducted to distinguish...

The Environmental DNA Calibration Study (ECALS) is a multi-year study to improve the understanding and interpretation of the detection of Asian carp DNA in environmental samples (eDNA) used in early detection monitoring. eDNA surveillance programs seek to detect the presence of genetic material (DNA in cells sloughed off in slime,...

Rocks with potential for karst formation are found in all 50 states. Damage due to karst subsidence and sinkhole collapse is a natural hazard of national scope. Repair of damage to buildings, highways, and other infrastructure represents a significant national cost. Sparse and incomplete data show that the average cost...

Knowledge of the capacity and flow of ecosystem services can help DoD land managers make decisions that enhance cost-effectiveness, minimize environmental damage, and maximize resources available for military missions. We demonstrated a methodology to quantify and map selected regulating services (RS), which helps land managers envision tradeoffs. Our objectives were...

Global earthquake activity rate model 1 (GEAR1) estimates the rate of shallow earthquakes with magnitudes 6–9 everywhere on Earth. It was designed to be reproducible and testable. Our preferred hybrid forecast is a log–linear blend of two parent forecasts based on the Global Centroid Moment Tensor (CMT) catalog (smoothing 4602...

This brief article describes refinements to the Graves and Pitarka (2010) broadband ground motion simulation methodology (GP2010 hereafter) that have been implemented in version 14.3 of the SCEC Broadband Platform (BBP). The updated version of our method on the current SCEC BBP is referred to as GP14.3. Our simulation technique...

Western sandpipers (Calidris mauri) are small (22-35 g) sexually dimorphic sandpipers, with males typically smaller than females. Western sandpipers frequently occur in mixed species flocks along with other Calidris species, including least sandpipers (Calidris minutilla) and dunlin (Calidris alpina), in the San Francisco Bay Estuary (SFBE) and are the most...

This case study considers two tern species that breed within the San Francisco Bay Estuary, Forster’s Terns (Sterna forsteri) and California Least Terns (Sternula antillarum browni). Forster’s Terns are medium-sized (140 g) terns that breed in coastal and interior marshes of North America. Forster’s Terns can exploit ephemeral habitats, and...

Diving ducks are the most abundant group of waterfowl that overwinter in the open bays and ponds of San Francisco Bay (SFB). Species within this group are primarily benthivores that dive to obtain their macroinvertebrate prey in bottom sediments, although at times they may eat plant matter or forage in...

A group of thunderstorms produced >4 in of rain during four periods of progressively more intense rainfall across a small part of a relatively high-elevation area of the northern Black Hills on 5 August 2014. The resulting hydrologic response was noteworthy in two very small headwater drainage basins, where the...