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Rhyolite is the most viscous of liquid magmas, so it was surprising that on 2 May 2008 at Chaitén Volcano, located in Chile’s southern Andean volcanic zone, rhyolitic magma migrated from more than 5 km depth in less than 4 hours and erupted explosively with only two days of detected precursory seismic activity....

Identifying links between nutritional condition of individuals and population trajectories greatly enhances our understanding of the ecology, conservation, and management of wildlife. For northern ungulates, the potential impacts of a changing climate to populations are predicted to be nutritionally mediated through an increase in the severity and variance in winter...

A draft update of the U.S. Environmental Protection Agency ambient water quality criteria (AWQC) for ammonia substantially lowers the ammonia AWQC, primarily due to the inclusion of toxicity data for freshwater mussels. However, most of the mussel data used in the updated AWQC were generated from water-only exposures and limited...

The generation of seismicity catalogs on synthetic fault networks holds the promise of providing key inputs into probabilistic seismic-hazard analysis, for example, the coefficient of variation, mean recurrence time as a function of magnitude, the probability of fault-to-fault ruptures, and conditional probabilities for foreshock-mainshock triggering. I employ a seismicity simulator...

Knowledge about the condition of vegetation cover and composition is critical for assessing the structure and function of ecosystems. To effectively quantify the impacts of a rapidly changing environment, methods to track long-term trends of vegetation must be precise, repeatable, and time- and cost-efficient. Measuring vegetation cover and composition in...

We used an individual-based population model to perform a viability analysis to simulate population growth (λ) of 167 elk (Cervus elaphus manitobensis; 71 male and 96 female) released in the Cumberland Mountains, Tennessee, to estimate sustainability (i.e., λ > 1.0) and identify the most appropriate options for managing elk restoration. We transported...

Closed- and open-path methane gas analyzers are used in eddy covariance systems to compare three potential methane emitting ecosystems in the Sacramento-San Joaquin Delta (CA, USA): a rice field, a peatland pasture and a restored wetland. The study points out similarities and differences of the systems in field experiments and...

Marine Protected Areas (MPAs) provide an important tool for conservation of marine ecosystems. To be most effective, these areas should be strategically located in a manner that supports ecosystem function. To inform marine spatial planning and support strategic establishment of MPAs within the California Current System, we identified areas predicted...

Habitat fragmentation and invasion by exotic species are regarded as major threats to the biodiversity of many ecosystems. We surveyed the plant communities of two types of remnant sagebrush-steppe fragments from nearby areas on the Snake River Plain of southeastern Idaho, USA. One type resulted from land use (conversion to...

The northeastern Gulf of Mexico contains some of the most diverse and productive marine habitat in the United States. Much of this habitat, located on the shelf edge in depths of 50 to 120 m, supports spawning for many economically important species, including groupers. Here, we couple acoustic surveys with...

FutureGen, as originally planned, was to be the world’s first coal-fueled, near-zero emissions power plant with fully integrated, 90% carbon capture and storage (CCS). From conception through siting and design, it enjoyed strong support from multiple stakeholder groups, which benefited the overall project. Understanding the stakeholder engagement process for this...

This paper presents the development of a two-dimensional, depth integrated, unsteady, free-surface model based on the shallow water equations. The development was motivated by the desire of balancing computational efficiency and accuracy by selective and conjunctive use of different numerical techniques. The base framework of the discrete model uses Godunov...

Food-grade CO2 was injected into a shallow aquifer through a perforated pipe placed horizontally 1–2 m below the water table at the Montana State University Zero Emission Research and Technology (MSU-ZERT) field site at Bozeman, Montana. The possible impact of elevated CO2 levels on...

The ensemble Kalman filter (EnKF) is susceptible to losing track of observations, or ‘diverging’, when applied to large chaotic systems such as atmospheric and ocean models. Past studies have demonstrated the adverse impact of sampling error during the filter’s update step. We examine how system dynamics affect EnKF performance, and...

Invasive species often have dramatic negative effects that lead to the deterioration and loss of biodiversity frequently coupled with the burden of expensive biocontrol programs and subversion of socioeconomic stability. The fauna and flora of oceanic islands are particularly susceptible to invasive species and the increase of global movements of...

Uranium–Pb (zircon) ages are linked with geochemical data for porphyry intrusions associated with giant porphyry Cu–Au systems at Oyu Tolgoi to place those rocks within the petrochemical framework of <a title="Learn more about...

Three years of weekly- to biweekly-resolved sediment-trap data show that almost 90% of the total flux of tests of the planktic foraminifer Globorotalia truncatulinoides to sediments in the northern Gulf of Mexico occurs in January and February. Comparison of δ18O from tests of non-encrusted Gl. truncatulinoides in sediment-trap samples with...

Greater sage-grouse (Centrocercus urophasianus) population declines may be caused by range-wide degradation of sagebrush (woody Artemisia spp.) steppe ecosystems. Understanding how greater sage-grouse use the landscape is essential for successful management. We assessed greater sage-grouse habitat selection on a landscape level in Jackson Hole, Wyoming. We used a Geographic Information...

To study the geochemical characteristics of 11 environmentally sensitive trace elements in the coals of the Permian Period from the Huainan coalfield, Anhui province, China, borehole samples of 336 coals, two partings, and four roof and floor mudstones were collected from mineable coal seams. Major elements and selected trace elements were determined by inductively coupled plasma optical emission spectrometry (ICP-OES), inductively coupled...

Four lithotypes (vitrain, bright clarain, clarain, and fusain) of a high volatile bituminous Springfield Coal from the Illinois Basin were characterized using advanced solid-state 13C nuclear magnetic resonance (NMR) spectroscopy. The NMR techniques included quantitative direct polarization/magic angle spinning (DP/MAS), cross polarization/total sideband suppression (CP/TOSS), dipolar dephasing, CHn selection, and recoupled C–H long-range dipolar dephasing techniques. The...

We investigated postbreeding resource selection by adult black-footed ferrets (Mustela nigripes) on a 452-ha black-tailed prairie dog (Cynomys ludovicianus) colony in the Conata Basin of South Dakota during 2007–2008. We used resource selection functions (RSFs) to evaluate relationships between numbers of ferret locations and numbers of prairie dog burrow openings...

Nearly all the mercury (Hg) in whole muscle from whitefish (Coregonus clupeaformis) and walleye (Sander vitreus) was present as methyl mercury (MeHg). The Hg content in whole muscle from whitefish and walleye was 0.04–0.09 and 0.14–0.81 ppm, respectively. The myofibril fraction contained...

Reintroductions are commonly employed to preserve intraspecific biodiversity in fragmented landscapes. However, reintroduced populations are frequently smaller and more geographically isolated than native populations. Mixing genetically, divergent sources are often proposed to attenuate potentially low genetic diversity in reintroduced populations that may result from small effective population sizes. However, a...

Two methods are compared for estimating the shape parameters of Pareto field-size (or pool-size) distributions for petroleum resource assessment. Both methods assume mature exploration in which most of the larger fields have been discovered. Both methods use the sizes of larger discovered fields to estimate the numbers and sizes of...

The relationship between virulence and overall within-host fitness of the fish rhabdovirus Infectious hematopoietic necrosis virus (IHNV) was empirically investigated in vivo for two virus isolates belonging to different IHNV genogroups that exhibit opposing host-specific virulence. U group isolates are more virulent in sockeye salmon and M group isolates are...