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This product consists of one tabular dataset and associated metadata of water quality information related to rivers, streams, and reservoirs in the Upper Mississippi River watershed between 2012 and 2016. This data release is a part of a national assessment of freshwater aquatic carbon fluxes. Data consist of organic and inorganic carbon related species, carbon dioxide and methane gas fluxes calculated from manual chamber measurements, nitrogen species, carbon isotopes, oxygen isotopes, cations, anions, trace metals, and various in situ measurements including: pH, water temperature, air temperature, barometric pressure, dissolved oxygen, turbidity, fluorescent dissolved organic matter, and specific conductance....
Categories: Data, Project; Types: Map Service, OGC WFS Layer, OGC WMS Layer, OGC WMS Service; Tags: Carbon, Fluorescent Dissolved Organic Matter (fDOM), Minnesota, Shingobee, Shingobee Headwaters Aquatic Ecosystems Project, All tags...
Our objective is to develop improved integration of data and models of soil and ecosystem processes at the regional scale in order to better quantify change in response disturbances, particularly drought. Specifically, we synthesize existing and generate new datasets of soil properties of soils form the Upper Colorado River Basin region of the Western US. Data types include geospatial databases and maps; soil physical, chemical, and biological datasets; soil hydrologic data; stream and river chemistry associated with regional mapping of soils; model input parameterizations and output data.
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The Long Valley Caldera in eastern California formed about 760,000 years ago following the eruption of ~600 km3 of high-silica rhyolite. The Long Valley volcanic-hydrothermal system contains sufficient heat to support the Casa Diablo binary geothermal power plant sited on the margin of the resurgent dome. Present day volcanic activity is evidenced by periods of seismicity and deformation and the presence of magmatic volatiles in thermal fluids. The U.S. Geological Survey (USGS) uses a variety of techniques to monitor the volcanic system that underlies the Long Valley Caldera. Monitoring data include measurements of seismicity and deformation and chemical analyses of thermal waters and gases that are emitted at...
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This data release contains tabular data (comma-separated-value files) of natural radiogenic isotopes of strontium, uranium, and thorium for samples of modern water, speleothems, associated with Fitton Cave, north central Arkansas, as well as rock that host the cave deposits. In addition, U-series ages (230Th/U dates and model 234U/238U dates) are calculated from those data for subsamples of speleothems. Stable isotopes of oxygen and carbon are reported for a subset of the stalagmite samples. Sample locations and descriptions as well as specific sub-sample imagery and narrative explanations are included as information supporting the analyses. Selected results are depicted as data plots in an accompanying Excel spreadsheet...
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Chemical changes in hot springs, as recorded by thermal waters and their mineral deposits, provide a window into the evolution of Yellowstone’s postglacial hydrothermal system. Travertine precipitated from thermal waters provide a record of chemical changes through time because they can be dated using U-series disequilibrium geochronology. These temporal data, along with measured radiogenic 87Sr/86Sr and stable isotope (carbon and oxygen) compositions and elemental concentrations, allow for the investigation of changes in hydrothermal system chemistry over time. This data release contains analyses conducted on samples of hydrothermal travertine collected from Upper and Lower Geyser Basins and near Madison Junction...
We investigated the relationships between foliar stable carbon isotope discrimination (Delta), % foliar N, and predawn water potentials (psi(pd)) and midday stomatal conductance ( g(s)) of Larrea tridentata across five Mojave Desert soils with different age-specific surface and sub-surface horizon development and soil hydrologies. We wished to elucidate how this long-lived evergreen shrub optimizes leaf-level physiological performance across soils with physicochemical characteristics that affect the distribution of limiting water and nitrogen resources. We found that in young, coarse alluvial soils that permit water infiltration to deeper soil horizons, % foliar N was highest and Delta, g(s) and psi(pd) were lowest,...
We used carbon and nitrogen isotopes to investigate changes in the diet of California condors from the Pleistocene to the recent. During the Pleistocene, condors from California fed on both terrestrial megafauna and marine mammals. Early accounts reported condors feeding on the carcasses of marine mammals, but by the late 1700s, condor diets had shifted predominantly to terrestrial animals, following the commercial harvesting of marine mammals and the development of cattle ranching on land. At present, dairy calves provided by humans significantly augment condor diet, constituting an artificial support of the current population. Reestablishing a marine mammal component in the condor diet may be an effective strategy...


    map background search result map search result map Water quality, quantity, and gas fluxes of the Upper Mississippi River basin (WY 2012-2016) Compositional data on gases collected at fumaroles, hot springs, and gas vents across the Long Valley Caldera, California, 1994 – 2020 Mineralogy, strontium (87Sr/86Sr), oxygen (18O/16O) and carbon (13C/12C) isotope composition, elemental concentrations, and U-Th disequilibrium ages for travertine deposits from various locations in Yellowstone National Park, USA Isotope analyses (234U/238U, 87Sr/86Sr, δ13C, and δ18O) and U-series disequilibrium ages for speleothem, water, and rock samples associated with Fitton Cave, Buffalo National River, Arkansas, USA Length, Weight, Energy Density, and Isotopic Values of Fish from Rivers in Northwest Alaska, 2015-2019 Nearshore Fish Isotope Values, Beaufort Sea, Alaska, 2017-2019 Isotope analyses (234U/238U, 87Sr/86Sr, δ13C, and δ18O) and U-series disequilibrium ages for speleothem, water, and rock samples associated with Fitton Cave, Buffalo National River, Arkansas, USA Compositional data on gases collected at fumaroles, hot springs, and gas vents across the Long Valley Caldera, California, 1994 – 2020 Mineralogy, strontium (87Sr/86Sr), oxygen (18O/16O) and carbon (13C/12C) isotope composition, elemental concentrations, and U-Th disequilibrium ages for travertine deposits from various locations in Yellowstone National Park, USA Nearshore Fish Isotope Values, Beaufort Sea, Alaska, 2017-2019 Length, Weight, Energy Density, and Isotopic Values of Fish from Rivers in Northwest Alaska, 2015-2019 Water quality, quantity, and gas fluxes of the Upper Mississippi River basin (WY 2012-2016)