Partitioning evapotranspiration in sparsely vegetated rangeland using a portable chamber
David I. Stannard, Mark A. Weltz
2006, Water Resources Research (42)
A portable chamber was used to separate evapotranspiration (ET) from a sparse, mixed‐species shrub canopy in southeastern Arizona, United States, into vegetation and soil components. Chamber measurements were made of ET from the five dominant species, and from bare soil, on 3 days during the monsoon season when the soil surface was...
Redox potential characterization and soil greenhouse gas concentration across a hydrological gradient in a Gulf coast forest
K. Yu, S.P. Faulkner, W.H. Patrick Jr.
2006, Chemosphere (62) 905-914
Soil redox potential (Eh), concentrations of oxygen (O2) and three greenhouse gases (CO2, CH4, and N2O) were measured in the soil profile of a coastal forest at ridge, transition, and swamp across a hydrological gradient. The results delineated a distinct boundary in soil Eh and O2 concentration between the ridge...
Effects of enhanced zinc and copper in drinking water on spatial memory and fear conditioning
L.D. Chrosniak, L.N. Smith, C.G. McDonald, B.F. Jones, J.M. Flinn
2006, Journal of Geochemical Exploration (88) 91-94
Ingestion of enhanced zinc can cause memory impairments and copper deficiencies. This study examined the effect of zinc supplementation, with and without copper, on two types of memory. Rats raised pre- and post-natally on 10 mg/kg ZnCO3 or ZnSO4 in the drinking water were tested in a fear-conditioning experiment at...
Analysis of environmental variation in a Great Plains reservoir using principal components analysis and geographic information systems
J.M. Long, W.L. Fisher
2006, Lake and Reservoir Management (22) 132-140
We present a method for spatial interpretation of environmental variation in a reservoir that integrates principal components analysis (PCA) of environmental data with geographic information systems (GIS). To illustrate our method, we used data from a Great Plains reservoir (Skiatook Lake, Oklahoma) with longitudinal variation in physicochemical conditions. We measured...
Effects of water removal on a Hawaiian stream ecosystem
R. A. Kinzie III, C. Chong, J. Devrell, D. Lindstrom, R. Wolff
2006, Pacific Science (60) 1-47
A 3-year study of Wainiha River on Kaua'i, Hawai'i, was carried out to determine the impact that water removal had on key stream ecosystem parameters and functions. The study area included a diversion dam for a hydroelectric plant that removes water at an elevation of 213 m and returns it...
Accumulation of contaminants in fish from wastewater treatment wetlands
L. B. Barber, S.H. Keefe, Ronald C. Antweiler, Howard E. Taylor, R.D. Wass
2006, Environmental Science & Technology (40) 603-611
Increasing demands on water resources in arid environments make reclamation and reuse of municipal wastewater an important component of the water budget. Treatment wetlands can be an integral part of the water-reuse cycle providing both water-quality enhancement and habitat functions. When used for habitat, the bioaccumulation potential...
Evidence that sea lamprey control led to recovery of the burbot population in Lake Erie
M.A. Stapanian, C.P. Madenjian, L.D. Witzel
2006, Transactions of the American Fisheries Society (135) 1033-1043
Between 1987 and 2003, the abundance of burbot Lota lota in eastern Lake Erie increased significantly, especially in Ontario waters. We considered four hypotheses to explain this increase: (1) reduced competition with lake trout Salvelinus namaycush, the other major coldwater piscivore in Lake Erie; (2) increased abundance of the two main prey species,...
Geochemical patterns of arsenic-enriched ground water in fractured, crystalline bedrock, Northport, Maine, USA
G. Lipfert, A.S. Reeve, W.C. Sidle, R. Marvinney
2006, Applied Geochemistry (21) 528-545
High mean As concentrations of up to 26.6 ??mol/L (1990 ??g/L) occur in ground water collected from a fractured-bedrock system composed of sulfidic schist with granitic to dioritic intrusions. Sulfides in the bedrock are the primary source of the As in the ground water, but the presence of arsenopyrite in...
Storage and transit time of chemicals in thick unsaturated zones under rangeland and irrigated cropland, High Plains, United States
P.B. McMahon, K.F. Dennehy, B. W. Bruce, J.K. Böhlke, R. L. Michel, J.J. Gurdak, D.B. Hurlbut
2006, Water Resources Research (42)
In 2000-2002, three rangeland and six irrigated sites were instrumented to assess the storage and transit time of chemicals in thick (15 to 50 m) unsaturated zones (UZ) in the High Plains. These processes are likely to influence relations between land use and groundwater quality, yet they have not been...
Numerical modeling of a long-term in situ chemical osmosis experiment in the Pierre Shale, South Dakota
A.M. Garavito, H. Kooi, C. E. Neuzil
2006, Advances in Water Resources (29) 481-492
We have numerically modeled evolving fluid pressures and concentrations from a nine-year in situ osmosis experiment in the Pierre Shale, South Dakota. These data were obtained and recently interpreted by one of us (C.E.N.) as indicating a potentially significant role for chemical osmosis in media like the Pierre Shale. That...
Rocks of the Columbia Hills
S. W. Squyres, R. E. Arvidson, D.L. Blaney, B. C. Clark, L. Crumpler, W. H. Farrand, S. Gorevan, Kenneth E. Herkenhoff, J. Hurowitz, A. Kusack, H.Y. McSween, D. W. Ming, R.V. Morris, S. W. Ruff, A. Wang, A. Yen
2006, Journal of Geophysical Research E: Planets (111)
The Mars Exploration Rover Spirit has identified five distinct rock types in the Columbia Hills of Gusev crater. Clovis Class rock is a poorly sorted clastic rock that has undergone substantial aqueous alteration. We interpret it to be aqueously altered ejecta deposits formed by impacts into basaltic materials. Wishstone Class...
Puhimau thermal area: a window into the upper east rift zone of Kilauea Volcano, Hawaii?
K.A. McGee, A. J. Sutton, T. Elias, M.P. Doukas, T.M. Gerlach
2006, Pure and Applied Geophysics (163) 837-851
We report the results of two soil CO2 efflux surveys by the closed chamber circulation method at the Puhimau thermal area in the upper East Rift Zone (ERZ) of Kilauea volcano, Hawaii. The surveys were undertaken in 1996 and 1998 to constrain how much CO2 might be reaching the ERZ...
The vertical hydraulic conductivity of an aquitard at two spatial scales
D.J. Hart, K. R. Bradbury, D. T. Feinstein
2006, Ground Water (44) 201-211
Aquitards protect underlying aquifers from contaminants and limit recharge to those aquifers. Understanding the mechanisms and quantity of ground water flow across aquitards to underlying aquifers is essential for ground water planning and assessment. We present results of laboratory testing for shale hydraulic conductivities, a methodology for determining the vertical...
Changes in late-winter snowpack depth, water equivalent, and density in Maine, 1926-2004
G.A. Hodgkins, R. W. Dudley
2006, Conference Paper, Hydrological Processes
Twenty-three snow-course sites in and near Maine, USA, with records spanning at least 50 years through to 2004 were tested for changes over time in snowpack depth, water equivalent, and density in March and April. Of the 23 sites, 18 had a significant decrease (Mann-Kendall test, p < 0??1) in...
Effects of land cover on water table, soil moisture, evapotranspiration, and groundwater recharge: A Field observation and analysis
Y.-K. Zhang, K. E. Schilling
2006, Journal of Hydrology (319) 328-338
The effects of land cover on water table, soil moisture, evapotranspiration, and groundwater recharge were studied with water level measurements collected from two monitoring wells over a period of 122 days. The two wells were installed under similar conditions except that one was drilled on the east side of a...
D/H ratios and hydrogen exchangeability of type-II kerogens with increasing thermal maturity
G.P. Lis, A. Schimmelmann, Maria Mastalerz
2006, Organic Geochemistry (37) 342-353
Stable isotope ratios of non-exchangeable hydrogen (??Dn) and of carbon were measured in type-II kerogens from two suites of Late Devonian to Early Mississippian black shale, one from the New Albany Shale (Illinois Basin) and the other from the Exshaw Formation (Alberta Basin). The largely marine-derived organic matter had similar...
Radiolaria and pollen records from 0 to 50 ka at ODP Site 1233: Continental and marine climate records from the Southeast Pacific
N. G. Pisias, L. Heusser, C. Heusser, S. W. Hostetler, A.C. Mix, M. Weber
2006, Quaternary Science Reviews (25) 455-473
Site 1233 drilled during Leg 202 of the Ocean Drilling Program provides a detailed record of marine and continental climate change in the Southeast Pacific and South American continent. Splits from over 500 samples taken at 20 cm intervals for quantitative analysis of radiolarian and pollen populations yield a temporal...
Characterization and identification of Na-Cl sources in ground water
S.V. Panno, Keith C. Hackley, H.-H. Hwang, S.E. Greenberg, I.G. Krapac, S. Landsberger, D. J. O’Kelly
2006, Ground Water (44) 176-187
Elevated concentrations of sodium (Na+) and chloride (Cl -) in surface and ground water are common in the United States and other countries, and can serve as indicators of, or may constitute, a water quality problem. We have characterized the most prevalent natural and anthropogenic sources of Na+ and Cl-...
Cross-shelf subtidal variability in San Pedro Bay during summer, 2001
P. Hamilton, M.A. Noble, J. Largier, L.K. Rosenfeld, G. Robertson
2006, Continental Shelf Research (26) 681-702
A total of 16 moorings were deployed across the San Pedro shelf, one of the two wider embayments in the Southern California Bight, from near the surfzone to the upper-slope. On the middle and outer shelf in the summer of 2001, the currents flowed strongly equatorward at the surface and...
Three-dimensional model for multi-component reactive transport with variable density groundwater flow
X. Mao, H. Prommer, D.A. Barry, C.D. Langevin, B. Panteleit, L. Li
2006, Environmental Modelling and Software (21) 615-628
PHWAT is a new model that couples a geochemical reaction model (PHREEQC-2) with a density-dependent groundwater flow and solute transport model (SEAWAT) using the split-operator approach. PHWAT was developed to simulate multi-component reactive transport in variable density groundwater flow. Fluid density in PHWAT depends not on only the concentration of...
Relation of fish communities to environmental conditions in urban streams of the Wasatch Front, Utah
E.M. Giddings, L. R. Brown, T.M. Short, M. R. Meador
2006, Western North American Naturalist (66) 155-168
Twenty-eight sites along the Wasatch Front, north central Utah, representing the range ot urban land use intensity for wadeable streams of the area, were sampled in September 2000. Fish communities were assessed by single-pass electrofishing, and physical habitat and water-quality characteristics were measured. On average, nonnative species comprised 54% of...
The importance of diverse data types to calibrate a watershed model of the Trout Lake Basin, Northern Wisconsin, USA
R. J. Hunt, D. T. Feinstein, C.D. Pint, Marilyn P. Anderson
2006, Journal of Hydrology (321) 286-296
As part of the USGS Water, Energy, and Biogeochemical Budgets project and the NSF Long-Term Ecological Research work, a parameter estimation code was used to calibrate a deterministic groundwater flow model of the Trout Lake Basin in northern Wisconsin. Observations included traditional calibration targets (head, lake stage, and baseflow observations)...
Estimates of suspended sediment entering San Francisco Bay from the Sacramento and San Joaquin Delta, San Francisco Bay, California
L.J. McKee, N. K. Ganju, D. H. Schoellhamer
2006, Journal of Hydrology (323) 335-352
This study demonstrates the use of suspended-sediment concentration (SSC) data collected at Mallard Island as a means of determining suspended-sediment load entering San Francisco Bay from the Sacramento and San Joaquin River watersheds. Optical backscatter (OBS) data were collected every 15 min during water years (WYs) 1995-2003 and converted to...
Spring migration of Northern Pintails from Texas and New Mexico, USA
D.A. Haukos, M. R. Miller, D.L. Orthmeyer, John Y. Takekawa, J. P. Fleskes, Michael L. Casazza, W.M. Perry, J.A. Moon
2006, Waterbirds (29) 127-136
We used satellite transmitters (platform transmitting terminals or PTTs) during 2002 and 2003 to document spring migration timing, routes, stopover sites, and nesting sites of adult female Northern Pintails (Anas acuta) from major wintering areas of the Gulf Coast (N = 20) and Playa Lakes Regions (PLR, N = 20)...
The airborne lava-seawater interaction plume at Kilauea Volcano, Hawai'i
M. Edmonds, T.M. Gerlach
2006, Earth and Planetary Science Letters (244) 83-96
Lava flows into the sea at Kīlauea Volcano, Hawaiʻi, and generates an airborne gas and aerosol plume. Water (H2O), hydrogen chloride (HCl), carbon dioxide (CO2), nitrogen dioxide (NO2) and sulphur dioxide (SO2) gases were quantified in the plume in 2004–2005, using Open Path Fourier Transform infra-red Spectroscopy. The molar abundances...
