Past and future changes in climate and hydrological indicators in the US Northeast
K. Hayhoe, C.P. Wake, T.G. Huntington, L. Luo, M.D. Schwartz, J. Sheffield, E. Wood, B. Anderson, J. Bradbury, A. DeGaetano, T.J. Troy, D. Wolfe
2007, Climate Dynamics (28) 381-407
To assess the influence of global climate change at the regional scale, we examine past and future changes in key climate, hydrological, and biophysical indicators across the US Northeast (NE). We first consider the extent to which simulations of twentieth century climate from nine atmosphere-ocean general circulation models (AOGCMs) are...
Effects of surface-water irrigation on sources, fluxes, and residence times of water, nitrate, and uranium in an alluvial aquifer
John Karl Bohlke, Ingrid M. Verstraeten, Thomas F. Kraemer
2007, Applied Geochemistry (22) 152-174
Effects of surface-water irrigation on an alluvial aquifer were evaluated using chemical and isotopic data including δ2H, δ18O, 3H, δ3He, Ar, Ne, N2, δ15N, and 234U/238U activity ratios in a transect of nested wells in the North Platte River valley in western Nebraska, USA. The data were used to evaluate sources and fluxes of H2O, <span...
The role of headwater streams in downstream water quality
R. B. Alexander, E.W. Boyer, R. A. Smith, G. E. Schwarz, R. B. Moore
2007, Journal of the American Water Resources Association (43) 41-59
Knowledge of headwater influences on the water-quality and flow conditions of downstream waters is essential to water-resource management at all governmental levels; this includes recent court decisions on the jurisdiction of the Federal Clean Water Act (CWA) over upland areas that contribute to larger downstream water bodies. We review current...
Cytherellid species (Ostracoda) and their significance to the Late Quaternary events in the Santos Basin, Brazil
C.T. Bergue, J.C. Coimbra, T. M. Cronin
2007, Senckenbergiana Maritima (37) 5-12
Four autochthonous cytherellid species (Cytherella serratula (BRADY, 1880), C. hermargentina WHATLEY et al. 1998, C. pleistocenica sp. nov. and C. santosensis sp. nov.) have been identified from two offshore cores (44 samples) within the Santos Basin. The distribution of these ostracodes is controlled by local hydrological conditions such as the...
Factors influencing ground-water recharge in the eastern United States
B. T. Nolan, R. W. Healy, P.E. Taber, K. Perkins, K.J. Hitt, D.M. Wolock
2007, Journal of Hydrology (332) 187-205
Ground-water recharge estimates for selected locations in the eastern half of the United States were obtained by Darcian and chloride-tracer methods and compared using statistical analyses. Recharge estimates derived from unsaturated-zone (RUZC) and saturated-zone (RSZC) chloride mass balance methods are less variable (interquartile ranges or IQRs are 9.5 and 16.1...
Concentration, UV-spectroscopic characteristics and fractionation of DOC in stormflow from an urban stream, Southern California, USA
John A. Izbicki, Isabel Pimentel, Russell Johnson, George R. Aiken, Jerry Leenheer
2007, Environmental Chemistry (4) 35-48
The composition of dissolved organic carbon (DOC) in stormflow from urban areas has been greatly altered, both directly and indirectly, by human activities and there is concern that there may be public health issues associated with DOC, which has unknown composition from different sources within urban watersheds. This...
Space geodetic observation of expansion of the San Gabriel Valley, California, aquifer system, during heavy rainfall in winter 2004-2005
N.E. King, D. Argus, J. Langbein, D.C. Agnew, G. Bawden, R.S. Dollar, Z. Liu, D. Galloway, E. Reichard, A. Yong, F.H. Webb, Y. Bock, K. Stark, D. Barseghian
2007, Journal of Geophysical Research B: Solid Earth (112)
[1] Starting early in 2005, the positions of GPS stations in the San Gabriel valley region of southern California showed statistically significant departures from their previous behavior. Station LONG moved up by about 47 mm, and nearby stations moved away from LONG by about 10 mm....
Heat transport in the Red Lake Bog, Glacial Lake Agassiz Peatlands
J.M. McKenzie, D. I. Siegel, Donald O. Rosenberry, P.H. Glaser, Clifford I. Voss
2007, Hydrological Processes (21) 369-378
We report the results of an investigation on the processes controlling heat transport in peat under a large bog in the Glacial Lake Agassiz Peatlands. For 2 years, starting in July 1998, we recorded temperature at 12 depth intervals from 0 to 400 cm within a vertical peat profile at...
Hydrologic response of the Crow Wing Watershed, Minnesota, to mid-Holocene climate change
M. Person, P. Roy, H. Wright, W. Gutowski Jr., E. Ito, T. Winter, D. Rosenberry, D. Cohen
2007, Geological Society of America Bulletin (119) 363-376
In this study, we have integrated a suite of Holocene paleoclimatic proxies with mathematical modeling in an attempt to obtain a comprehensive picture of how watersheds respond to past climate change. A three-dimensional surface-water-groundwater model was developed to assess the effects of mid-Holocene climate change on water resources within the...
Oxygen isotopes in nitrite: Analysis, calibration, and equilibration
K.L. Casciotti, John Karl Bohlke, M.R. McIlvin, Stanley J. Mroczkowski, Janet E. Hannon
2007, Analytical Chemistry (79) 2427-2436
Nitrite is a central intermediate in the nitrogen cycle and can persist in significant concentrations in ocean waters, sediment pore waters, and terrestrial groundwaters. To fully interpret the effect of microbial processes on nitrate (NO3-), nitrite (NO2-), and nitrous oxide (N2O) cycling in these systems, the nitrite pool must be...
Water use regimes: Characterizing direct human interaction with hydrologic systems
Peter K. Weiskel, Richard M. Vogel, Peter A. Steeves, Philip J. Zarriello, Leslie A. DeSimone, Kernell G. Ries III
2007, Water Resources Research (43)
The sustainability of human water use practices is a rapidly growing concern in the United States and around the world. To better characterize direct human interaction with hydrologic systems (stream basins and aquifers), we introduce the concept of the water use regime. Unlike scalar indicators of anthropogenic hydrologic stress in...
Numerical modelling to determine freshwater/saltwater interface configuration in a low-gradient coastal wetland aquifer
E. Swain, M. Wolfert
2007, Conference Paper, IAHS-AISH Publication
A coupled hydrodynamic surface-water/groundwater model with salinity transport is used to examine the aquifer salinity interface in the coastal wetlands of Everglades National Park in Florida, USA. The hydrology differs from many other coastal areas in that inland water levels are often higher than land surface, the flow gradients are...
Use of dissolved chloride concentrations in tributary streams to support geospatial estimates of Cl contamination potential near Skiatook Lake, northeastern Oklahoma
C. A. Rice, M.M. Abbott, R. A. Zielinski
2007, Applied Geochemistry (22) 2193-2206
Releases of NaCl-rich (>100 000 mg/L) water that is co-produced from petroleum wells can adversely affect the quality of ground and surface waters. To evaluate produced water impacts on lakes, rivers and streams, an assessment of the contamination potential must be attainable using reliable and cost-effective methods. This study examines...
Isotopic analysis of N and O in nitrite and nitrate by sequential selective bacterial reduction to N2O
John Karl Bohlke, Richard L. Smith, Janet E. Hannon
2007, Analytical Chemistry (79) 5888-5895
Nitrite is an important intermediate species in the biogeochemical cycling of nitrogen, but its role in natural aquatic systems is poorly understood. Isotopic data can be used to study the sources and transformations of NO2- in the environment, but methods for independent isotopic analyses of NO2- in the presence of...
Comparison of fate and transport of isoxaflutole to atrazine and metolachlor in 10 Iowa rivers
Michael T. Meyer, Elisabeth A. Scribner, Stephen J. Kalkhoff
2007, Environmental Science & Technology (41) 6933-6939
Isoxaflutole (IXF), a newer low application rate herbicide, was introduced for weed control in corn (Zea mays) to use as an alternative to widely applied herbicides such as atrazine. The transport of IXF in streamwater has not been well-studied. The fate and transport of IXF and two of its degradation...
Ecohydrological controls on soil moisture and hydraulic conductivity within a pinyon‐juniper woodland
I. Lebron, M.D. Madsen, D.G. Chandler, D.A. Robinson, O. Wendroth, J. Belnap
2007, Water Resources Research (43)
The impact of pinyon‐juniper woodland encroachment on rangeland ecosystems is often associated with a reduction of streamflow and recharge and an increase in soil erosion. The objective of this study is to investigate vegetational control on seasonal soil hydrologic properties along a 15‐m transect in pinyon‐juniper woodland with biocrust. We...
Whole-ecosystem study shows rapid fish-mercury response to changes in mercury deposition
R.C. Harris, J.W.M. Rudd, M. Amyot, Christopher L. Babiarz, K.G. Beaty, P.J. Blanchfield, R.A. Bodaly, B.A. Branfireun, C.C. Gilmour, J.A. Graydon, A. Heyes, H. Hintelmann, J.P. Hurley, C.A. Kelly, David P. Krabbenhoft, S.E. Lindberg, R.P. Mason, M.J. Paterson, C.L. Podemski, A. Robinson, K.A. Sandilands, G.R. Southworthn, Louis, Michael T. Tate
2007, Proceedings of the National Academy of Sciences of the United States of America (104) 16586-16591
Methylmercury contamination of fisheries from centuries of industrial atmospheric emissions negatively impacts humans and wild-life worldwide. The response of fish methylmercury concentrations to changes in mercury deposition has been difficult to establish because sediments/soils contain large pools of historical contamination, and many factors in addition to deposition affect fish mercury....
Adequacy of satellite derived rainfall data for stream flow modeling
G. Artan, Hussein Gadain, Jodie Smith, Kwasi Asante, C.J. Bandaragoda, J. P. Verdin
2007, Natural Hazards (43) 167-185
Floods are the most common and widespread climate-related hazard on Earth. Flood forecasting can reduce the death toll associated with floods. Satellites offer effective and economical means for calculating areal rainfall estimates in sparsely gauged regions. However, satellite-based rainfall estimates have had limited use in flood forecasting and hydrologic stream...
Spatial and temporal variations in silver contamination and toxicity in San Francisco Bay
A.R. Flegal, Cynthia L. Brown, S. Squire, J.R.M. Ross, G.M. Scelfo, S. Hibdon
2007, Environmental Research (105) 34-52
Although San Francisco Bay has a "Golden Gate", it may be argued that it is the "Silver Estuary". For at one time the Bay was reported to have the highest levels of silver in its sediments and biota, along with the only accurately measured values of silver in solution, of...
Investigation of reductive dechlorination supported by natural organic carbon
Heather V. Rectanus, Mark A. Widdowson, Francis H. Chapelle, C.A. Kelly, John T. Novak
2007, Ground Water Monitoring and Remediation (27) 53-62
Because remediation timeframes using monitored natural attenuation may span decades or even centuries at chlorinated solvent sites, new approaches are needed to assess the long-term sustainability of reductive dechlorination in ground water systems. In this study, extraction procedures were used to investigate the mass of indigenous organic carbon in aquifer...
Quantification of changes in metal loading from storm runoff, Merse River (Tuscany, Italy)
Briant A. Kimball, F. Bianchi, Katherine Walton-Day, Robert L. Runkel, M. Nannucci, A. Salvadori
2007, Mine Water and the Environment (26) 209-216
The Merse River in Tuscany is affected by mine drainage and the weathering of mine wastes along several kilometres of its catchment. The metal loading to the stream was quantified by defining detailed profiles of discharge and concentration, using tracer-dilution and synoptic-sampling techniques. During the course of a field experiment...
Composition of pore water in lake sediments, research site "B", Osage County, Oklahoma: Implications for lake water quality and benthic organisms
Robert A. Zielinski, William N. Herkelrath, James K. Otton
2007, Applied Geochemistry (22) 2177-2192
Shallow ground water at US Geological Survey research site B in northeastern Oklahoma is contaminated with NaCl-rich brine from past and present oil production operations. Contaminated ground water provides a potential source of salts, metals, and hydrocarbons to sediment and water of adjacent Skiatook Lake. A former brine storage pit...
Geochemical and geophysical examination of submarine groundwater discharge and associated nutrient loading estimates into Lynch Cove, Hood Canal, WA
P.W. Swarzenski, F. W. Simonds, A.J. Paulson, S. Kruse, C. Reich
2007, Environmental Science & Technology (41) 7022-7029
Geochemical tracer data (i.e., 222Rn and four naturally occurring Ra isotopes), electromagnetic (EM) seepage meter results, and high-resolution, stationary electrical resistivity images were used to examine the bi-directional (i.e., submarine groundwater discharge and recharge) exchange of a coastal aquifer with seawater. Our study site for these experiments was Lynch Cove,...
The oxygen-18 isotope approach for measuring aquatic metabolism in high-productivity waters
Craig R. Tobias, John Karl Bohlke, Judson W. Harvey
2007, Limnology and Oceanography (52) 1439-1453
We examined the utility of δ18O2 measurements in estimating gross primary production (P), community respiration (R), and net metabolism (P : R) through diel cycles in a productive agricultural stream located in the midwestern U.S.A. Large diel swings in O2(±200 µmol L−1) were accompanied by large diel variation in δ18O2 (±10‰). Simultaneous...
Formation and disruption of aquifers in southwestern Chryse Planitia, Mars
J.A.P. Rodriguez, K. L. Tanaka, J.S. Kargel, J. M. Dohm, R. Kuzmin, A.G. Fairen, S. Sasaki, G. Komatsu, D. Schulze-Makuch, Y. Jianguo
2007, Icarus (191) 545-567
We present geologic evidence suggesting that after the development of Mars' cryolithosphere, the formation of aquifers in southwestern Chryse Planitia and their subsequent disruption led to extensive regional resurfacing during the Late Hesperian, and perhaps even during the Amazonian. In our model, these aquifers formed preferentially along thrust faults associated...
