Geographic Information Systems (GIS) for la République Islamique de Mauritanie (PRISM-II) phase V (phase V, deliverable 92)
John D. Horton, Cliff D. Taylor
2015, Open-File Report 2013-1280-T
In 1996, at the request of the Government of the Islamic Republic of Mauritania, a team of U.S. Geological Survey (USGS) scientists produced a strategic plan for the acquisition, improvement and modernization of multidisciplinary sets of data to support the growth of the Mauritanian minerals sector and to highlight the...
Geologic map of Mauritania (phase V, deliverables 51a, 51b, and 51c)
Dwight Bradley, Holly Motts, John D. Horton, Stuart A. Giles, Cliff D. Taylor
2015, Open-File Report 2013-1280-A1
In 1996, at the request of the Government of the Islamic Republic of Mauritania, a team of U.S. Geological Survey (USGS) scientists produced a strategic plan for the acquisition, improvement and modernization of multidisciplinary sets of data to support the growth of the Mauritanian minerals sector and to highlight the...
Completion of the 2011 National Land Cover Database for the conterminous United States – Representing a decade of land cover change information
Collin G. Homer, Jon Dewitz, Limin Yang, Suming Jin, Patrick Danielson, George Z. Xian, John Coulston, Nathaniel Herold, James Wickham, Kevin Megown
2015, Photogrammetric Engineering and Remote Sensing (81) 345-354
The National Land Cover Database (NLCD) provides nationwide data on land cover and land cover change at the native 30-m spatial resolution of the Landsat Thematic Mapper (TM). The database is designed to provide five-year cyclical updating of United States land cover and associated changes. The recent release of NLCD...
Structure map of Mauritania (phase V, deliverables 52a and 52b)
Dwight Bradley, John D. Horton, Holly A. Motts, Cliff D. Taylor
2015, Open-File Report 2013-1280-A2
In 1996, at the request of the Government of the Islamic Republic of Mauritania, a team of U.S. Geological Survey (USGS) scientists produced a strategic plan for the acquisition, improvement and modernization of multidisciplinary sets of data to support the growth of the Mauritanian minerals sector and to highlight the...
Correspondence of biological condition models of California streams at statewide and regional scales
Jason T. May, Larry R. Brown, Andrew C. Rehn, Ian R. Waite, Peter R Ode, Raphael D Mazor, Kenneth C Schiff
2015, Environmental Monitoring and Assessment (187)
We used boosted regression trees (BRT) to model stream biological condition as measured by benthic macroinvertebrate taxonomic completeness, the ratio of observed to expected (O/E) taxa. Models were developed with and without exclusion of rare taxa at a site. BRT models are robust, requiring few assumptions compared with traditional modeling...
Quantifying and predicting fuels and the effects of reduction treatments along successional and invasion gradients in sagebrush habitats
Douglas J. Shinneman, David S. Pilliod, Robert Arkle, Nancy F. Glenn
2015, Report
Sagebrush shrubland ecosystems in the Great Basin are prime examples of how altered successional trajectories can create dynamic fuel conditions and, thus, increase uncertainty about fire risk and behavior. Although fire is a natural disturbance in sagebrush, post-fire environments are highly susceptible to conversion to an invasive grass-fire regime (often...
Hydrogeologic map of the Islamic Republic of Mauritania (phase V, deliverable 56), Synthesis of hydrologic data (phase V, deliverable 57), and chemical hydrologic map of the Islamic Republic of Mauritania (added value)
Michael J. Friedel, Carol A. Finn, John D. Horton
2015, Open-File Report 2013-1280-C
A hydrogeologic study was conducted to support mineral-resource assessment activities in Mauritania, Africa. Airborne magnetic depth estimates reveal two primary groundwater basins: the porous coastal Continental Terminal Basin (fill deposits); and the interior, fractured interior Taoudeni Basin. In the Continental Terminal Basin, there is uniform vertical recharge and localized discharge...
An integrated approach to conjunctive-use analysis with the one-water hydrologic flow model, MODFLOW-OWHM
Scott Boyce, Randall T. Hanson
2015, Conference Paper, Proceedings: MODFLOW and more 2015: Modeling a complex world
The MODFLOW-2005 (MF) family of hydrologic simulators has diverged into multiple versions designed for specific needs, thus limiting their use to their respective designs. The One-Water Hydrologic Flow Model (MF-OWHM v1.0) is an integrated hydrologic flow model that is an enhanced fusion of multiple MF versions. While maintaining compatibility with...
Vegetation composition, nutrient, and sediment dynamics along a floodplain landscape
Nancy B. Rybicki, Gregory E. Noe, Cliff R. Hupp, Myles Robinson
2015, River Systems (21) 109-123
Forested floodplains are important landscape features for retaining river nutrients and sediment loads but there is uncertainty in how vegetation influences nutrient and sediment retention. In order to understand the role of vegetation in nutrient and sediment trapping, we quantified species composition and the uptake of nutrients in plant material...
Drought monitoring and assessment: Remote sensing and modeling approaches for the Famine Early Warning Systems Network
Gabriel B. Senay, Naga Manohar Velpuri, Stefanie Bohms, Michael Budde, Claudia Young, James Rowland, James Verdin
2015, Book chapter
Drought monitoring is an essential component of drought risk management. It is usually carried out using drought indices/indicators that are continuous functions of rainfall and other hydrometeorological variables. This chapter presents a few examples of how remote sensing and hydrologic modeling techniques are being used to generate a suite of...
River corridor science: Hydrologic exchange and ecological consequences from bedforms to basins
Judson Harvey, Michael Gooseff
2015, Water Resources Research (51) 6893-6922
Previously regarded as the passive drains of watersheds, over the past 50 years, rivers have progressively been recognized as being actively connected with off-channel environments. These connections prolong physical storage and enhance reactive processing to alter water chemistry and downstream transport of materials and energy. Here we propose river corridor...
Processes limiting depth of arroyo incision: Examples from the Rio Puerco, New Mexico
Eleanor R. Griffin, Jonathan M. Friedman
2015, Conference Paper, Proceedings of the 5th Federal Interagency Hydrologic Modeling Conference and the 10th Federal Interagency Sedimentation Conference
We examined channel flow and suspended sediment transport processes within the lower Rio Puerco arroyo, located in semi-arid north-central New Mexico, in an attempt to answer the question: Why did arroyo incision stop by about 1936? Channel flow model results show that in the narrow, incised channel of 1936, the...
Origins and bioavailability of dissolved organic matter in groundwater
Yuan Shen, Francis H. Chapelle, Eric W. Strom, Ronald Benner
2015, Biogeochemistry (122) 61-78
Dissolved organic matter (DOM) in groundwater influences water quality and fuels microbial metabolism, but its origins, bioavailability and chemical composition are poorly understood. The origins and concentrations of dissolved organic carbon (DOC) and bioavailable DOM were monitored during a long-term (2-year) study of groundwater in a fractured-rock aquifer in the...
Using chromate to investigate the impact of natural organics on the surface reactivity of nanoparticulate magnetite
Andrew L. Swindle, Isabelle M. Cozzarelli, Andrew S. Elwood Madden
2015, Environmental Science & Technology (49) 2156-2162
Chromate was used as a chemical probe to investigate the size-dependent influence of organics on nanoparticle surface reactivity. Magnetite–chromate sorption experiments were conducted with ∼90 and ∼6 nm magnetite nanoparticles in the presence and absence of fulvic acid (FA), natural organic matter (NOM), and isolated landfill leachate (LL). Results indicated...
Observational changes to the natural flow regime in Lee Creek in relation to altered precipitation patterns and its implication for fishes
Michael R. Gatlin, James M. Long, Donald J. Turton
2015, Proceedings of the Oklahoma Academy of Science (95) 135-146
The natural flow regime is important for structuring streams and their resident ichthyofauna and alterations to this regime can have cascading consequences. We sought to determine if changes in hydrology could be attributed to changes in precipitation in a minimally altered watershed (Lee Creek). The stream flow regime was analyzed...
Estimating mean long-term hydrologic budget components for watersheds and counties: An application to the commonwealth of Virginia, USA
Ward E. Sanford, David L. Nelms, Jason P. Pope, David L. Selnick
2015, Hydrology: Current Research (6) 1-22
Mean long-term hydrologic budget components, such as recharge and base flow, are often difficult to estimate because they can vary substantially in space and time. Mean long-term fluxes were calculated in this study for precipitation, surface runoff, infiltration, total evapotranspiration (ET), riparian ET, recharge, base flow (or groundwater discharge) and...
Identifying sediment sources in the sediment TMDL process
Allen C. Gellis, Faith A. Fitzpatrick, Joseph P. Schubauer-Berigan, R.B. Landy, Lillian E. Gorman Sanisaca
2015, Conference Paper, Proceedings of the 3rd Joint Federal Interagency Conference (10th Federal Interagency Sedimentation Conference and 5th Federal Interagency Hydrologic Modeling Conference)
Sediment is an important pollutant contributing to aquatic-habitat degradation in many waterways of the United States. This paper discusses the application of sediment budgets in conjunction with sediment fingerprinting as tools to determine the sources of sediment in impaired waterways. These approaches complement monitoring, assessment, and modeling of sediment erosion,...
Mobilization of microspheres from a fractured soil during intermittent infiltration events
Sanjay Mohanty, Mark Bulicek, David W. Metge, Ronald W. Harvey, Joseph N. Ryan, Alexandria B. Boehm
2015, Vadose Zone Journal (14)
Pathogens or biocolloids mobilized in the vadose zone may consequently contaminate groundwater. We found that microspheres were mobilized from a fractured soil during intermittent rainfall and the mobilization was greater when the microsphere size was larger and when the soil had greater water permeability.The vadose zone filters pathogenic microbes from...
Effects of natural organic matter properties on the dissolution kinetics of zinc oxide nanoparticles
Chuanjia Jiang, George R. Aiken, Heileen Hsu-Kim
2015, Environmental Science & Technology (49) 11476-11484
The dissolution of zinc oxide (ZnO) nanoparticles (NPs) is a key step of controlling their environmental fate, bioavailability, and toxicity. Rates of dissolution often depend upon factors such as interactions of NPs with natural organic matter (NOM). We examined the effects of 16 different NOM isolates on the dissolution kinetics...
Stable-isotope and solute-chemistry approaches to flow characterization in a forested tropical watershed, Luquillo Mountains, Puerto Rico
Martha A. Scholl, James B. Shanley, Sheila F. Murphy, Jane K Willenbring, Marcie Occhi, Grizelle Gonzalez
2015, Applied Geochemistry (63) 484-497
The prospect of changing climate has led to uncertainty about the resilience of forested mountain watersheds in the tropics. In watersheds where frequent, high rainfall provides ample runoff, we often lack understanding of how the system will respond under conditions of decreased rainfall or drought. Factors that govern water supply,...
Numerical modeling of injection, stress and permeability enhancement during shear stimulation at the Desert Peak Enhanced Geothermal System
David Dempsey, Sharad Kelkar, Nick Davatzes, Stephen H. Hickman, Daniel Moos
2015, International Journal of Rock Mechanics and Mining Sciences (78) 190-206
Creation of an Enhanced Geothermal System relies on stimulation of fracture permeability through self-propping shear failure that creates a complex fracture network with high surface area for efficient heat transfer. In 2010, shear stimulation was carried out in well 27-15 at Desert Peak geothermal field, Nevada, by injecting cold water...
Twentieth-century shifts in forest structure in California: Denser forests, smaller trees, and increased dominance of oaks
Patrick J. McIntyre, James H. Thorne, Christopher R. Dolanc, Alan L. Flint, Lorraine E. Flint, Maggi Kelly, David D. Ackerly
2015, Proceedings of the National Academy of Sciences (112) 1458-1463
We document changes in forest structure between historical(1930s) and contemporary (2000s) surveys of California vegetation through comparisons of tree abundance and size across the state and within several ecoregions. Across California, tree density in forested regions increased by 30% between the two time periods, whereas forest biomass in the same...
High-speed limnology: Using advanced sensors to investigate spatial variability in biogeochemistry and hydrology
John T. Crawford, Luke C. Loken, Nora J. Casson, Colin Smith, Amanda G. Stone, Luke A. Winslow
2015, Environmental Science & Technology (49) 442-450
Advanced sensor technology is widely used in aquatic monitoring and research. Most applications focus on temporal variability, whereas spatial variability has been challenging to document. We assess the capability of water chemistry sensors embedded in a high-speed water intake system to document spatial variability. This new sensor platform continuously samples...
Concentrations and distributions of metals associated with dissolved organic matter from the Suwannee River (GA, USA)
M. Keshia Kuhn, Elisabeth Neubauer, Thilo Hofmann, Frank von der Kammer, George R. Aiken, Patricia A. Maurice
2015, Environmental Engineering Science (32) 54-65
Concentrations and distributions of metals in Suwannee River (SR) raw filtered surface water (RFSW) and dissolved organic matter (DOM) processed by reverse osmosis (RO), XAD-8 resin (for humic and fulvic acids [FA]), and XAD-4 resin (for “transphilic” acids) were analyzed by asymmetrical flow field-flow fractionation (AsFlFFF). SR samples were compared...
Spatial and temporal variation in recruitment and growth of Channel Catfish Alabama bass and Tallapoosa Bass in the Tallapoosa River and associated tributaries
Elise R. Irwin, Taconya Goar
2015, Cooperator Science Series FWS/CSS -116
Effects of hydrology on growth and hatching success of age-0 black basses and Channel Catfish were examined in regulated and unregulated reaches of the Tallapoosa River, Alabama. Species of the family Centrarchidae, Ictalurus punctatus Channel Catfish and Pylodictis olivaris Flathead Catfish were also collected from multiple tributaries in the basin....