Striegl, Robert G

8 items:

A reservoir of nitrate beneath desert soils A large reservoir of bioavailable nitrogen (up to approximately 10(4) kilograms of nitrogen per hectare, as nitrate) has been previously overlooked in studies of global nitrogen distribution. The reservoir has been accumulating in subsoil zones of arid regions throughout the Holocene. Consideration of the subsoil reservoir raises estimates of vadose-zone nitrogen inventories by 14 to 71% for warm deserts and arid shrublands worldwide and by 3 to 16% globally. Subsoil nitrate accumulation indicates long-term leaching from desert soils, impelling further evaluation of nutrient dynamics in xeric ecosystems. Evidence that subsoil accumulations are readily mobilized raises concern about groundwater contamination after... Categories: Publication; Types: Citation
Monitoring radionuclide contamination in the unsaturated zone - lessons learned at the Amargosa Desert Research Site, Nye County, Nevada Categories: Publication; Types: Citation
Changes in the chemistry of lakes and precipitation in high-elevation national parks in the western United States, 1985?1999 High-elevation lakes in the western United States are sensitive to atmospheric deposition of sulfur and nitrogen due to fast hydrologic flushing rates, short growing seasons, an abundance of exposed bedrock, and a lack of well-developed soils. This sensitivity is reflected in the dilute chemistry of the lakes, which was documented in the U.S. Environmental Protection Agency's Western Lake Survey of 1985. Sixty-nine lakes in seven national parks sampled during the 1985 survey were resampled during fall 1999 to investigate possible decadal-scale changes in lake chemistry. In most lakes, SO4 concentrations were slightly lower in 1999 than in 1985, consistent with a regional decrease in precipitation SO4 concentrations... Categories: Publication; Types: Citation, Journal Citation; Tags: American Geophysical Union, Water Resources Research
Monitoring radionuclide contamination in the unsaturated zone - lessons learned at the Amargosa Desert Research Site, Nye County, Nevada Categories: Publication; Types: Citation
Role of aquatic networks in the boreal carbon cycle Categories: Publication; Types: Citation

ScienceBase brings together the best information it can find about USGS researchers and offices to show connections to publications, projects, and data. We are still working to improve this process and information is by no means complete. If you don't see everything you know is associated with you, a colleague, or your office, please be patient while we work to connect the dots. Feel free to contact sciencebase@usgs.gov.