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Abstract has not been submitted
Categories: Publication; Types: Citation; Tags: Science
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No abstract available.
Categories: Publication; Types: Citation; Tags: Science
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[No abstract available]
Categories: Publication; Types: Citation; Tags: Science
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The Muddy Creek watershed, part of the Upper Colorado River watershed, is a semi-arid catchment in a sagebrush steppe ecosystem. A synoptic watershed assessment was conducted in 2010 to identify areas within the watershed that are more susceptible to mobilization of trace elements that occur in soils forming on marine shale. Samples of soil, stream sediment, and water were collected and assayed for major elements and a suite of trace elements. Formation waters discharged from two wells within the watershed were sampled in 2011 to evaluate their potential contribution of organic carbon, nitrogen (N) species, and trace elements to surface waters. In FY2012, analyses of the soil, rock, and water samples collected...
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Limits on the time and financial resources available for monitoring efforts, coupled with the complexities of natural resources and stakeholders, are challenges in resource monitoring. To help address these and related challenges, the USGS Monitoring Team (MT) has linked conceptual monitoring specialists with habitat and wildlife biologists to inform and develop creative, scientifically defensible approaches for monitoring the status and trends of populations and habitats across the WLCI region. This collaboration has led to spatially balanced monitoring designs that will make it possible to interpret conditions across the WLCI region and a mechanism for integrating species’ distributions and population responses...
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Regional-scale studies, such as those being conducted for the WLCI, are well suited for the use of remote-sensing techniques. Derivative products from remote-sensing instruments, such as Landsat, have been used successfully for decades in studies of geology, vegetation, environmental change, and many other types of scientific research. The continuous coverage of Landsat data since 1972 makes it possible to establish baseline conditions in areas affected by renewable and nonrenewable energy development. In this study, various Landsat datasets are being used to map current and pre-development conditions in the WLCI study area for a selected set of scientific interests. Landsat scenes have been mosaicked to produce...
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Labeled DDD [ 1,1-dichlor-o-2,2-bis(p-chlorophenyl)-ethane] was formed from C14-labeled DDT in the presence of yeast. The formation of DDD from DDE [1,1-dichloro-2,2-bis (p-chlorophenyl)-ethylene] was not observed, indicating that a reductive dechlorination of DDT occurs.
Categories: Publication; Types: Citation; Tags: Science
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In the WLCI region, the quality and condition of sagebrush steppe is a concern given the extent of rangewide land-use change, habitat conversion, and rapid energy development in sagebrush systems. Three migratory songbird species are considered near-obligates of sagebrush shrublands: Brewer’s and sagebrush sparrows and sage thrasher, all of which are designated Species of Great Conservation Need in Wyoming (Wyoming Game and Fish Department, 2010) and nest in Green River Basin. In collaboration with the WGFD, we initiated this multiphase project to address the WLCI management need to identify the condition and distribution of sagebrush songbird habitats and key drivers of change in those habitats. In Phase I (2008...
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Muddy Creek, a tributary to the Little Snake River, is a semi-arid catchment that drains about 1,200 mi2 in south-central Wyoming. The drainage basin is characterized as a sagebrush steppe ecosystem. The area is undergoing energy exploration and development, including conventional natural gas wells and coalbed natural gas wells. Geologic formations that underlie the drainage basin include soluble marine shales, which are a natural source of dissolved solids (for example, sodium, chloride, and sulfate) and Se. As a result, the water quality of Muddy Creek is naturally high in dissolved constituents, including Se. The WDEQ has listed chloride and Se as impairments to aquatic life for Muddy Creek. Dissolved solids...
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The Forest and Rangeland Ecosystem Science Center 's mission is to provide scientific understanding and the technology needed to support sound management and conservation of our nation's natural resources, with emphasis on western ecosystems. The scientists from FRESC capitalize on their diverse expertise to answer critically important scientific questions shaped by the equally diverse environments of the western United States. FRESC scientists collaborate with each other and with partners to provide rigorous, objective, and timely information and guidance for the management and conservation of biological systems in the West and worldwide. Research activities are concentrated in Washington, Oregon, Idaho, Nevada,...
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Most volcanic eruptions that occur shortly after a large distant earthquake do so by random chance. A few compelling cases for earthquake-triggered eruptions exist, particularly within 200 km of the earthquake, but this phenomenon is rare in part because volcanoes must be poised to erupt in order to be triggered by an earthquake (1). Large earthquakes often perturb volcanoes in more subtle ways by triggering small earthquakes and changes in spring discharge and groundwater levels (1, 2). On page 80 of this issue, Brenguier et al. (3) provide fresh insight into the interaction of large earthquakes and volcanoes by documenting a temporary change in seismic velocity beneath volcanoes in Honshu, Japan, after the devastating...
Categories: Publication; Types: Citation; Tags: Science
Double fertilization and the associated formation of endosperm have long been considered unique and defining characters (autapomorphies) of the angiosperms. During normal fertilization in Ephedra nevadensis, a nonflowering seed plant, fusion of a second sperm nucleus with the ventral canal nucleus occurs regularly within the egg cytoplasm. The occurrence of double fertilization in Ephedra assumes added significance in light of its critical phylogenetic position as a basal member of the most closely related extant group of seed plants (Gnetales) to angiosperms. Thus, double fertilization in angiosperms and Ephedra may represent an evolutionary homology. Published in Science, volume 547, issue 4945, on pages 951 -...
Categories: Publication; Types: Citation, Journal Citation; Tags: Science
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In summary, as little as 30 parts of ethyl mercury p-toluene sulfonanilide per million (12.5 ppm of Hg) in the diet of adult pheasants was generally fatal within 2 to 3 months of feeding. Ten parts of the compound per million (4.2 ppm of Hg) in the diet reduced egg production 50 to 80 percent and increased embryo mortality in the few eggs laid. Mercury residues in 14 eggs were 0.9 to 3.1 ppm, comparable to those in eggs of pheasants fed methyl mercury dicyandiamide (3), in which hatchability was also reduced. Since similar residues of mercury have been found in eggs of wild pheasants (3) -and several species of aquatic birds (2), we conclude that mercury pollution may be sufficiently high in some areas to affect...
Categories: Publication; Types: Citation; Tags: Science
Lack of a 19th-century baseline temperature against which 20th-century warming can be referenced constitutes a deficiency in understanding recent climate change. Combination of borehole temperature profiles, which contain a memory of surface temperature changes in previous centuries, with the meteorological archive of surface air temperatures can provide a 19th-century baseline temperature tied to the current observational record. A test case in Utah, where boreholes are interspersed with meteorological stations belonging to the Historical Climatological Network, yields a noise reduction in estimates of 20th-century warming and a baseline temperature that is 0.6� +/- 6 0.1�C below the 1951 to 1970 mean temperature...
Categories: Publication; Types: Citation, Journal Citation; Tags: Science
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Brains of juvenile gray bats, Myotis grisescens, found dead beneath maternity roosts in two Missouri caves contained lethal concentrations of dieldrin. One colony appeared to be abnormally small, and more dead bats were found a year after the juvenile bats had been collected. This is the first report to link the field mortality of bats directly to insecticide residues acquired through the food chain.
Categories: Publication; Types: Citation; Tags: Science
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[No abstract available]
Categories: Publication; Types: Citation; Tags: Science
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The Gorkha earthquake (magnitude 7.8) on 25 April 2015 and later aftershocks struck South Asia, killing ~9000 people and damaging a large region. Supported by a large campaign of responsive satellite data acquisitions over the earthquake disaster zone, our team undertook a satellite image survey of the earthquakes’ induced geohazards in Nepal and China and an assessment of the geomorphic, tectonic, and lithologic controls on quake-induced landslides. Timely analysis and communication aided response and recovery and informed decision-makers. We mapped 4312 coseismic and postseismic landslides. We also surveyed 491 glacier lakes for earthquake damage but found only nine landslide-impacted lakes and no visible satellite...
Categories: Publication; Types: Citation; Tags: Science
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Theory predicts that higher biodiversity in the tropics is maintained by specialized interactions among plants and their natural enemies that result in conspecific negative density dependence (CNDD). By using more than 3000 species and nearly 2.4 million trees across 24 forest plots worldwide, we show that global patterns in tree species diversity reflect not only stronger CNDD at tropical versus temperate latitudes but also a latitudinal shift in the relationship between CNDD and species abundance. CNDD was stronger for rare species at tropical versus temperate latitudes, potentially causing the persistence of greater numbers of rare species in the tropics. Our study reveals fundamental differences in the nature...
Categories: Publication; Types: Citation; Tags: Science
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Over the last 20 years, it has become clear that ice ages are characterized by glacial as well as climatic instability on millennial time scales. In his Perspective, Colman highlights two recent papers investigating the role of glacial meltwater and continental drainage in this instability. The results suggest a fundamental instability feedback between ocean circulation and ice sheet dynamics and provides an explanation for why instability was greatest at times of intermediate ice volume.
Categories: Publication; Types: Citation; Tags: Science