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Publication Extents

Not all publications have extents, not all extents are completely accurate
Soil ecology of a rock outcrop ecosystem: Abiotic stresses, soil respiration, and microbial community profiles in limestone cedar glades
Jennifer M. Cartwright, E. Kudjo Advised by Dzantor
2015, Thesis
Limestone cedar glades are a type of rock outcrop ecosystem characterized by shallow soil and extreme hydrologic conditions—seasonally ranging from xeric to saturated—that support a number of plant species of conservation concern. Although a rich botanical literature exists on cedar glades, soil biochemical processes and the ecology of soil microbial...
Variably-saturated groundwater modeling for optimizing managed aquifer recharge using trench infiltration
Victor M. Heilweil, Jerome Benoit, Richard W. Healy
2015, Hydrological Processes (29) 310-319
Spreading-basin methods have resulted in more than 130 million cubic meters of recharge to the unconfined Navajo Sandstone of southern Utah in the past decade, but infiltration rates have slowed in recent years because of reduced hydraulic gradients and clogging. Trench infiltration is a promising alternative technique for increasing recharge...
Pesticide concentrations in frog tissue and wetland habitats in alandscape dominated by agriculture
Kelly L. Smalling, Rebecca Reeves, Erin L. Muths, Mark W. Vandever, William A. Battaglin, Michelle Hladik, Clay L. Pierce
2015, Science of the Total Environment (502) 80-90
Habitat loss and exposure to pesticides are likely primary factors contributing to amphibian decline in agricultural landscapes. Conservation efforts have attempted to restore wetlands lost through landscape modifications to reduce contaminant loads in surface waters and providing quality habitat to wildlife. The benefits of this increased wetland area, perhaps especially...
Assessing the impacts of climate and land use and land cover change on the freshwater availability in the Brahmaputra River basin
Md Shahriar Pervez, Geoffrey M. Henebry
2015, Journal of Hydrology (3) 285-311
Study Region: Brahmaputra River basin in South Asia.   Study Focus: The Soil and Water Assessment Tool was used to evaluate sensitivities and patterns in freshwater availability due to projected climate and land use changes in the Brahmaputra basin. The daily observed discharge at Bahadurabad station in Bangladesh was used to calibrate and validate...
Vegetation controls on weathering intensity during the last deglacial transition in southeast Africa
Sarah J. Ivory, Michael M. McGlue, Geoffrey S. Ellis, Anne-Marie Lézine, Andrew S. Cohen, Annie Vincens
2015, PLoS ONE (9)
Tropical climate is rapidly changing, but the effects of these changes on the geosphere are unknown, despite a likelihood of climatically-induced changes on weathering and erosion. The lack of long, continuous paleo-records prevents an examination of terrestrial responses to climate change with sufficient detail to answer questions about how systems...
Using scenario planning to evaluate the impacts of climate change on wildlife populations and communities in the Florida Everglades
Christopher P. Catano, Stephanie S. Romañach, James M. Beerens, Leonard G. Pearlstine, Laura A. Brandt, Kristen M. Hart, Frank J. Mazzotti, Joel C. Trexler
2015, Environmental Management (55) 807-823
It is uncertain how climate change will impact hydrologic drivers of wildlife population dynamics in freshwater wetlands of the Florida Everglades, or how to accommodate this uncertainty in restoration decisions. Using projections of climate scenarios for the year 2060, we evaluated how several possible futures could affect wildlife populations (wading...
User guide to Exploration and Graphics for RivEr Trends (EGRET) and dataRetrieval: R packages for hydrologic data
Robert M. Hirsch, Laura A. De Cicco
2015, Techniques and Methods 4-A10
Evaluating long-term changes in river conditions (water quality and discharge) is an important use of hydrologic data. To carry out such evaluations, the hydrologist needs tools to facilitate several key steps in the process: acquiring the data records from a variety of sources, structuring it in ways that facilitate the...
Development of a spatially universal framework for classifying stream assemblages with application to conservation planning for Great Lakes lotic fish communities
James E. McKenna Jr., Jeffrey S. Schaeffer, Jana S. Stewart, Michael T. Slattery
2015, Restoration Ecology (23) 167-178
Classifications are typically specific to particular issues or areas, leading to patchworks of subjectively defined spatial units. Stream conservation is hindered by the lack of a universal habitat classification system and would benefit from an independent hydrology-guided spatial framework of units encompassing all aquatic habitats at multiple spatial scales within...
Modeling long-term trends of chlorinated ethene contamination at a public supply well
Francis H. Chapelle, Leon J. Kauffman, Mark A. Widdowson
2015, Journal of the American Water Resources Association (51) 1-13
A mass-balance solute-transport modeling approach was used to investigate the effects of dense nonaqueous phase liquid (DNAPL) volume, composition, and generation of daughter products on simulated and measured long-term trends of chlorinated ethene (CE) concentrations at a public supply well. The model was built by telescoping a calibrated regional three-dimensional...
Hydrologic response to valley-scale structure in alpine headwaters
Anne A. Weekes, Christian E. Torgersen, David R. Montgomery, Andrea Woodward, Susan M. Bolton
2015, Hydrological Processes (29) 356-372
Few systematic studies of valley-scale geomorphic drivers of streamflow regimes in complex alpine headwaters have compared response between catchments. As a result, little guidance is available for regional-scale hydrological research and monitoring efforts that include assessments of ecosystem function. Physical parameters such as slope, elevation range, drainage area and bedrock...
Change in agricultural land use constrains adaptation of national wildlife refuges to climate change
Christopher M. Hamilton, Wayne E. Thogmartin, Volker C. Radeloff, Andrew J. Plantinga, Patricia J. Heglund, Sebastian Martinuzzi, Anna M. Pidgeon
2015, Environmental Conservation (42) 12-19
Land-use change around protected areas limits their ability to conserve biodiversity by altering ecological processes such as natural hydrologic and disturbance regimes, facilitating species invasions, and interfering with dispersal of organisms. This paper informs USA National Wildlife Refuge System conservation planning by predicting future land-use change on lands within 25...
Trend analyses with river sediment rating curves
Jonathan A. Warrick
2015, Hydrological Processes (29) 936-949
Sediment rating curves, which are fitted relationships between river discharge (Q) and suspended-sediment concentration (C), are commonly used to assess patterns and trends in river water quality. In many of these studies it is assumed that rating curves have a power-law form (i.e., C = aQb, where a and b...
Assessing stand water use in four coastal wetland forests using sapflow techniques: annual estimates, errors and associated uncertainties
Ken W. Krauss, Jamie A. Duberstein, William H. Conner
2015, Hydrological Processes (29) 112-127
Forests comprise approximately 37% of the terrestrial land surface and influence global water cycling. However, very little attention has been directed towards understanding environmental impacts on stand water use (S) or in identifying rates of S from specific forested wetlands. Here, we use sapflow techniques to address two separate but linked objectives:...
A 3400 year paleolimnological record of prehispanic human–environment interactions in the Holmul region of the southern Maya lowlands
David B. Wahl, Francisco Estrada-Belli, Lysanna Anderson
2015, Palaeogeography, Palaeoclimatology, Palaeoecology (379-380) 17-31
The timing, magnitude and drivers of late Holocene environmental change in the Holmul region of the southern Maya lowlands are examined by combining paleoenvironmental and archeological data. Environmental proxy analyses on a ~ 3350 cal yr lacustrine sediment record include pollen, charcoal, loss on ignition, magnetic suscep- tibility, and elemental...
Estimating evapotranspiration and groundwater flow from water-table fluctuations for a general wetland scenario
Martha L. Carlson Mazur, Michael J. Wiley, Douglas A. Wilcox
2015, Ecohydrology (7) 378-390
The use of diurnal water-table fluctuation methods to calculate evapotranspiration (ET) and groundwater flow is of increasing interest in ecohydrological studies. Most studies of this type, however, have been located in riparian wetlands of semi-arid regions where groundwater levels are consistently below topographic surface elevations and precipitation events are infrequent....
Limnology of the Green Lakes Valley: Phytoplankton ecology and dissolved organic matter biogeochemistry at a long-term ecological research site
Matthew P. Miller, Diane M. McKnight
2015, Plant Ecology and Diversity (8) 689-702
Background: Surface waters are the lowest points in the landscape, and therefore serve as excellent integrators and indicators of changes taking place in the surrounding terrestrial and atmospheric environment.Aims: Here we synthesise the findings of limnological studies conducted during the past 15 years in streams and lakes in the Green...
Hindcast of water availability in regional aquifer systems using MODFLOW Farm Process
Wolfgang Schmid, Randall T. Hanson, Claudia C. Faunt, Steven P. Phillips
2015, Conference Paper, Predictions for hydrology, ecology, and water resources management: Using data and models to benefit society
Coupled groundwater and surface-water components of the hydrologic cycle can be simulated by the Farm Process for MODFLOW (MF-FMP) in both irrigated and non-irrigated areas and aquifer-storage and recovery systems. MF-FMP is being applied to three productive agricultural regions of different scale in the State of California, USA, to assess...
Forecasting the combined effects of urbanization and climate change on stream ecosystems: from impacts to management options
Karen C. Nelson, Margaret A. Palmer, James E. Pizzuto, Glenn E. Moglen, Paul L. Angermeier, Robert H. Hilderbrand, Mike Dettinger, Katharine Hayhoe
2015, Journal of Applied Ecology (46) 154-163
Streams collect runoff, heat, and sediment from their watersheds, making them highly vulnerable to anthropogenic disturbances such as urbanization and climate change. Forecasting the effects of these disturbances using process-based models is critical to identifying the form and magnitude of likely impacts. Here, we integrate a new biotic model with...
Geology and geophysics applied to groundwater hydrology at Fort Irwin, California
David C. Buesch, editor(s)
2014, Open-File Report 2013-1024
Geologic and geophysical investigations in the vicinity of Fort Irwin National Training Center, California, have been completed in support of groundwater investigations, and are presented in eight chapters of this report. A generalized surficial geologic map along with field and borehole investigations conducted during 2010–11 provide a lithostratigraphic and structural...
Time-domain electromagnetic surveys at Fort Irwin, San Bernardino County, California, 2010–12
Matthew K. Burgess, Paul A. Bedrosian
David C. Buesch, editor(s)
2014, Open-File Report 2013-1024-F
Between 2010 and 2012, a total of 79 time-domain electromagnetic (TEM) soundings were collected in 12 groundwater basins in the U.S. Army Fort Irwin National Training Center (NTC) study area to help improve the understanding of the hydrogeology of the NTC. The TEM data are discussed in this chapter in...
Comparison of mineral weathering and biomass nutrient uptake in two small forested watersheds underlain by quartzite bedrock, Catoctin Mountain, Maryland, USA
Karen C. Rice, Jason R. Price
2014, Aquatic Geochemistry (20) 225-242
To quantify chemical weathering and biological uptake, mass-balance calculations were performed on two small forested watersheds located in the Blue Ridge Physiographic Province in north-central Maryland, USA. Both watersheds, Bear Branch (BB) and Fishing Creek Tributary (FCT), are underlain by relatively unreactive quartzite bedrock. Such unreactive bedrock and associated low...
Collaborative modelling and integrated decision support system analysis of a developed terminal lake basin
Richard G. Niswonger, Kip K. Allander, Anne E. Jeton
2014, Journal of Hydrology (517) 521-537
A terminal lake basin in west-central Nevada, Walker Lake, has undergone drastic change over the past 90 yrs due to upstream water use for agriculture. Decreased inflows to the lake have resulted in 100 km2 decrease in lake surface area and a total loss of fisheries due to salinization. The ecologic health of...
Prevalence of pure versus mixed snow cover pixels across spatial resolutions in alpine environments: implications for binary and fractional remote sensing approaches
David J. Selkowitz, Richard Forster, Megan K. Caldwell
2014, Remote Sensing (6) 12478-12508
Remote sensing of snow-covered area (SCA) can be binary (indicating the presence/absence of snow cover at each pixel) or fractional (indicating the fraction of each pixel covered by snow). Fractional SCA mapping provides more information than binary SCA, but is more difficult to implement and may not be feasible with...
Estimating the magnitude and frequency of floods for urban and small, rural streams in Georgia, South Carolina, and North Carolina
Toby D. Feaster, Anthony J. Gotvald, J. Curtis Weaver
2014, Book, Proceedings of the 3rd Joint Federal Interagency Conference on Sedimentation and Hydrologic Modeling
Reliable estimates of the magnitude and frequency of floods are essential for such things as the design of transportation and water-conveyance structures, Flood Insurance Studies, and flood-plain management. The flood-frequency estimates are particularly important in densely populated urban areas. A multistate approach was used to update methods for determining the...
Physically based method for measuring suspended-sediment concentration and grain size using multi-frequency arrays of acoustic-doppler profilers
David J. Topping, Scott Wright, Ronald E. Griffiths, David J. Dean
2014, Conference Paper, Proceedings of the 2015 Joint Federal Interagency Conference on Sedimentation and Hydrologic Modeling
As the result of a 12-year program of sediment-transport research and field testing on the Colorado River (6 stations in UT and AZ), Yampa River (2 stations in CO), Little Snake River (1 station in CO), Green River (1 station in CO and 2 stations in UT), and Rio Grande...