Evaluation of sulfate reduction at experimentally induced mixing interfaces using small-scale push-pull tests in an aquifer-wetland system
T.A. Kneeshaw, Jennifer T. McGuire, Erik W. Smith, Isabelle M. Cozzarelli
2007, Applied Geochemistry (22) 2618-2629
This paper presents small-scale push–pull tests designed to evaluate the kinetic controls on SO42-">SO42- reduction in situ at mixing interfaces between a wetland and aquifer impacted by landfill leachate at the Norman Landfill research site, Norman, OK. Quantifying the...
Mode of occurrence and environmental mobility of oil-field radioactive material at US Geological Survey research site B, Osage-Skiatook Project, northeastern Oklahoma
Robert A. Zielinski, James R. Budahn
2007, Applied Geochemistry (22) 2125-2137
Two samples of produced-water collected from a storage tank at US Geological Survey research site B, near Skiatook Lake in northeastern Oklahoma, have activity concentrations of dissolved 226Ra and 228Ra that are about 1500 disintegrations/min/L (dpm/L). Produced-water also contains minor amounts of small (5–50 μm) suspended grains of Ra-bearing BaSO4 (barite). Precipitation of radioactive...
Local structuring factors of invertebrate communities in ephemeral freshwater rock pools and the influence of more permanent water bodies in the region
M. Jocque, T. Graham, L. Brendonck
2007, Hydrobiologia (592) 271-280
We used three isolated clusters of small ephemeral rock pools on a sandstone flat in Utah to test the importance of local structuring processes on aquatic invertebrate communities. In the three clusters we characterized all ephemeral rock pools (total: 27) for their morphometry, and monitored their water quality, hydrology and...
Sources and transport of algae and nutrients in a Californian river in a semi-arid climate
Nobuhito Ohte, Randy A. Dahlgren, Steven R. Silva, Carol Kendall, Charles R. Kratzer, Daniel H. Doctor
2007, Freshwater Biology (52) 2476-2493
1. To elucidate factors contributing to dissolved oxygen (DO) depletion in the Stockton Deep Water Ship Channel in the lower San Joaquin River, spatial and temporal changes in algae and nutrient concentrations were investigated in relation to flow regime under the semiarid climate conditions. 2. Chlorophyll-a (chl-a) concentration and loads...
Cloud water in windward and leeward mountain forests: The stable isotope signature of orographic cloud water
M. A. Scholl, T. W. Giambelluca, S. B. Gingerich, M.A. Nullet, L.L. Loope
2007, Water Resources Research (43)
Cloud water can be a significant hydrologic input to mountain forests. Because it is a precipitation source that is vulnerable to climate change, it is important to quantify amounts of cloud water input at watershed and regional scales. During this study, cloud water and rain samples were collected monthly for...
Discontinuities in stream nutrient uptake below lakes in mountain drainage networks
C.D. Arp, M. A. Baker
2007, Limnology and Oceanography (52) 1978-1990
In many watersheds, lakes and streams are hydrologically linked in spatial patterns that influence material transport and retention. We hypothesized that lakes affect stream nutrient cycling via modifications to stream hydrogeomorphology, source-waters, and biological communities. We tested this hypothesis in a lake district of the Sawtooth Mountains, Idaho. Uptake of...
Tree and stand transpiration in a Midwestern bur oak savanna after elm encroachment and restoration thinning
H. Asbjornsen, M.D. Tomer, M. Gomez-Cardenas, L.A. Brudvig, C.M. Greenan, K. Schilling
2007, Forest Ecology and Management (247) 209-219
Oak savannas, once common in the Midwest, are now isolated remnants within agricultural landscapes. Savanna remnants are frequently encroached by invasive trees to become woodlands. Thinning and prescribed burning can restore savanna structure, but the ecohydrological effects of managing these remnants are poorly understood. In this study, we measured sap...
Rainfall limit of the N cycle on Earth
Stephanie A. Ewing, Greg Michalski, Mark Thiemens, R.C. Quinn, J. L. Macalady, S. Kohl, Scott D. Wankel, Carol Kendall, Christopher P McKay, Ronald Amundson
2007, Global Biogeochemical Cycles (21)
In most climates on Earth, biological processes control soil N. In the Atacama Desert of Chile, aridity severely limits biology, and soils accumulate atmospheric NO3−. We examined this apparent transformation of the soil N cycle using a series of ancient Atacama Desert soils (>2 My) that vary in rainfall (21...
Formation of mixed Al-Fe colloidal sorbent and dissolved-colloidal partitioning of Cu and Zn in the Cement Creek - Animas River Confluence, Silverton, Colorado
Laurence E. Schemel, Briant A. Kimball, Robert L. Runkel, Marisa H. Cox
2007, Applied Geochemistry (22) 1467-1484
Transport and chemical transformations of dissolved and colloidal Al, Fe, Cu and Zn were studied by detailed sampling in the mixing zone downstream from the confluence of Cement Creek (pH 4.1) with the Animas River (pH 7.6). Complete mixing resulted in...
Comparison of 15 evaporation methods applied to a small mountain lake in the northeastern USA
Donald O. Rosenberry, Thomas C. Winter, D.C. Buso, G.E. Likens
2007, Journal of Hydrology (340) 149-166
Few detailed evaporation studies exist for small lakes or reservoirs in mountainous settings. A detailed evaporation study was conducted at Mirror Lake, a 0.15 km2 lake in New Hampshire, northeastern USA, as part of a long-term investigation of lake hydrology. Evaporation was determined using 14 alternate evaporation methods during six...
Revisiting the cape cod bacteria injection experiment using a stochastic modeling approach
Reed M. Maxwell, Claire Welty, Ronald W. Harvey
2007, Environmental Science & Technology (41) 5548-5558
Bromide and resting-cell bacteria tracer tests conducted in a sandy aquifer at the U.S. Geological Survey Cape Cod site in 1987 were reinterpreted using a three-dimensional stochastic approach. Bacteria transport was coupled to colloid filtration theory through functional dependence of local-scale colloid transport parameters upon hydraulic conductivity and seepage velocity...
Water table fluctuations under three riparian land covers, Iowa (USA)
K. E. Schilling
2007, Hydrological Processes (21) 2415-2424
Water table depth is known to play an important role in nitrogen cycling in riparian zones, but little detailed monitoring of water table fluctuations has been reported. In this study, results of high-resolution water table monitoring under three common riparian land covers (forest, cool season grass, corn) were analysed to...
Climate variability controls on unsaturated water and chemical movement, High Plains aquifer, USA
J.J. Gurdak, R. T. Hanson, P.B. McMahon, B. W. Bruce, J.E. McCray, G.D. Thyne, R.C. Reedy
2007, Vadose Zone Journal (6) 533-547
Responses in the vadose zone and groundwater to interannual, interdecadal, and multidecadal climate variability have important implications for groundwater resource sustainability, yet they are poorly documented and not well understood in most aquifers of the USA. This investigation systematically examines the role of interannual to...
Distribution of selected halogenated organic compounds among suspended particulate, colloid, and aqueous phases in the Mississippi River and major tributaries
Colleen E. Rostad, S.R. Daniel
2007, Archives of Environmental Contamination and Toxicology (53) 151-158
Suspended particulate, colloid, and aqueous phases were separated and analyzed to determine spatial variation of specific organic compound transport associated with each phase in a dynamic river system. Sixteen sites along the Mississippi River and its major tributaries were sampled at low-flow conditions to maximize the possibility of equilibrium. Across...
Holocene sea level and climate change in the Black Sea: Multiple marine incursions related to freshwater discharge events
R.E. Martin, E. Leorri, P.P. McLaughlin
2007, Quaternary International (167-168) 61-72
Repeated marine invasions of the Black Sea during the Holocene have been inferred by many eastern scientists as resulting from episodes of marine inflow from the Mediterranean beneath a brackish outflow from the Black Sea. We support this scenario but a fundamental question remains: What caused the repeated marine invasions?...
Deglacial climate variability in central Florida, USA
Debra A. Willard, C.E. Bernhardt, G. R. Brooks, T. M. Cronin, T. Edgar, R. Larson
2007, Palaeogeography, Palaeoclimatology, Palaeoecology (251) 366-382
Pollen and ostracode evidence from lacustrine sediments underlying modern Tampa Bay, Florida, document frequent and abrupt climatic and hydrological events superimposed on deglacial warming in the subtropics. Radiocarbon chronology on well-preserved mollusk shells and pollen residue from core MD02-2579 documents continuous sedimentation in a variety of non-marine habitats in a...
The importance of subsurface geology for water source and vegetation communities in Cherokee Marsh, Wisconsin
A.M. Kurtz, J.M. Bahr, Q. J. Carpenter, Randal J. Hunt
2007, Wetlands (27) 189-202
Restoration of disturbed wetland systems is an important component of wetland mitigation, yet uncertainty remains about how hydrologic processes affect biologic processes and wetlands patterns. To design more effective restoration strategies and re-establish native plant communities in disturbed wetlands, it is imperative to understand undisturbed systems. A site within Cherokee...
Thioarsenates in geothermal waters of Yellowstone National Park: Determination, preservation, and geochemical importance
B. Planer-Friedrich, J. London, R. Blaine McCleskey, D. Kirk Nordstrom, D. Wallschlager
2007, Environmental Science & Technology (41) 5245-5251
Mono-, di-, tri-, and tetrathioarsenate, as well as methylated arsenic oxy- and thioanions, were determined besides arsenite and arsenate in geothermal waters of Yellowstone National Park using anion-exchange chromatography inductively coupled plasma mass spectrometry. Retention time match with synthetic standards, measured S:As ratios, and molecular electrospray mass spectra support 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...
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...
Effects of imposed salinity gradients on dissimilatory arsenate reduction, sulfate reduction, and other microbial processes in sediments from two California soda lakes
T.R. Kulp, S. Han, C.W. Saltikov, B.D. Lanoil, K. Zargar, Ron Oremland
2007, Applied and Environmental Microbiology (73) 5130-5137
Salinity effects on microbial community structure and on potential rates of arsenate reduction, arsenite oxidation, sulfate reduction, denitrification, and methanogenesis were examined in sediment slurries from two California soda lakes. We conducted experiments with Mono Lake and Searles Lake sediments over a wide range of salt concentrations...
A simulation-based approach for estimating premining water quality: Red Mountain Creek, Colorado
Robert L. Runkel, Briant A Kimball, Katherine Walton-Day, Philip L. Verplanck
2007, Applied Geochemistry (22) 1899-1918
Regulatory agencies are often charged with the task of setting site-specific numeric water quality standards for impaired streams. This task is particularly difficult for streams draining highly mineralized watersheds with past mining activity. Baseline water quality data obtained prior to mining are often non-existent and application of generic water quality...
Biological effects of anthropogenic contaminants in the San Francisco Estuary
B. Thompson, T. Adelsbach, Cynthia L. Brown, J. Hunt, James S. Kuwabara, J. Neale, H. Ohlendorf, Steven E. Schwarzbach, R. Spies, K. Taberski
2007, Environmental Research (105) 156-174
Concentrations of many anthropogenic contaminants in the San Francisco Estuary exist at levels that have been associated with biological effects elsewhere, so there is a potential for them to cause biological effects in the Estuary. The purpose of this paper is to...
GIS methodology for quantifying channel change in Las Vegas, Nevada
S.E. Buckingham, J.W. Whitney
2007, Journal of the American Water Resources Association (43) 888-898
This study applies spatial analyses to examine the consequences of accelerated urban expansion on a hydrologic system over a period of 24 years. Three sets of historical aerial photos are used in a GIS analysis to document the geomorphic history of Las Vegas Wash, which drains the rapidly growing Las...
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...
