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Source water controls on the character and origin of dissolved organic matter in streams of the Yukon River basin, Alaska
In many subsurface situations where human health and environmental quality are at risk (e.g., contaminant hydrogeology petroleum extraction, carbon sequestration, etc.),scientists and engineers are being asked by federal agency decision-makers to predict the fate of chemical species under conditions where both reactions and transport are processes of first-order importance.In 2002, a working group (WG) was formed by representatives of the U.S. Geological Survey, Environmental Protection Agency, Department of Energy Nuclear Regulatory Commission, Department of Agriculture, and Army Engineer Research and Development Center to assess the role of reactive transport modeling (RTM) in addressing these situations. Specifically...
Surface complexation studied via combined grazing-incidence EXAFS and surface diffraction: arsenate on hematite (0001) and (10–12)
X-ray diffraction [crystal-truncation-rod (CTR)] studies of the surface structure of moisture-equilibrated hematite reveal sites for complexation not present on the bulk oxygen-terminated surface, and impose constraints on the types of inner-sphere sorption topologies. We have used this improved model of the hematite surface to analyze grazing-incidence EXAFS results for arsenate sorption on the c (0001) and r (10–12) surfaces measured in two electric vector polarizations. This work shows that the reconfiguration of the surface under moist conditions is responsible for an increased adsorption density of arsenate complexes on the (0001) surface relative to predicted ideal termination, and an abundance of “edge-sharing”...
Relations between Hydrology and Solute Fluxes at the Five Water, Energy, and Biogeochemical Budget (WEBB) Watersheds of the United States Geological Survey
Joint 8th Federal Interagency Sedimentation Conference and 3rd Federal Interagency Hydrologic Modeling Conference
Risley, J., and Hay, L.E., 2006, eds. Joint 8th Federal Interagency Sedimentation Conference and 3rd Federal Interagency Hydrologic Modeling Conference, April 2-6, 2006, Reno, Nevada.
Line-conditioned excess: a new method for characterizing stable hydrogen and oxygen isotope ratios in hydrologic systems
Long-term changes in abundance and diversity of macrophyte and waterfowl populations in an estuary with exotic macrophytes and improving water quality
Transporte de sedimentos en corrientes naturals: revisión técnica de ecuaciones empíricas de predicción del arrastre de sedimentos de fondo
Sources and Transport of Sediment in the Watershed , in Phillips, S.W., ed., Synthesis of U.S. Geological Survey Science for the Chesapeake Bay Ecosystem and Implications for Environmental Management
Sediment and nutrient accumulation within lowland bottomland ecosystems - An example from the Atchafalaya River Basin, Louisiana: Proceedings Hydrology and Management of Forested Wetlands
Geomorphic monitoring of the Kissimmee River Restoration - 2006-2009: South Florida Water Management District
The interactions between vegetation and erosion: new directions for research at the interface of ecology and geomorphology
Vegetation and processes of erosion and deposition are interactive. An objective of this paper is to review selected studies that emphasize the interdependencies. The reviews suggest new directions for research uniting ecology and geomorphology – the sub-discipline of biogeomorphology. The research, which recently has become vigorous, includes the sources, movement, and fates of fluvial loads of sediment, organic carbon, nutrients, contaminants, and woody debris to low-energy storage sites; the function of biota in causing soil evolution, stability, and sequestration of carbon; the development of new methods to characterize watersheds based on edaphic conditions; and the refinement of current empirical and conceptual...