Evaluation of the factors controlling the time-dependent inactivation rate coefficients of bacteriophage MS2 and PRD1
R. Anders, C.V. Chrysikopoulos
2006, Environmental Science & Technology (40) 3237-3242
Static and dynamic batch experiments were conducted to study the effects of temperature and the presence of sand on the inactivation of bacteriophage MS2 and PRD1. The experimental data suggested that the inactivation process can be satisfactorily represented by a pseudo-first-order expression with time-dependent rate coefficients. The time-dependent rate coefficients...
Flow resistance dynamics in step‐pool stream channels: 1. Large woody debris and controls on total resistance
Andrew C. Wilcox, Ellen E. Wohl
2006, Water Resources Research (42)
Flow resistance dynamics in step‐pool channels were investigated through physical modeling using a laboratory flume. Variables contributing to flow resistance in step‐pool channels were manipulated in order to measure the effects of various large woody debris (LWD) configurations, steps, grains, discharge, and slope on total flow resistance. This entailed nearly...
Risk of Myxobolus cerebralis infection to rainbow trout in the Madison River, Montana, USA
R.C. Krueger, B.L. Kerans, E.R. Vincent, C. Rasmussen
2006, Ecological Applications (16) 770-783
Myxobolus cerebralis, the parasite that causes salmonid whirling disease, has had detrimental effects on several salmonid populations in the Intermountain West, including the rainbow trout in the Madison River, Montana, USA. The goal of this study was to examine relationships among characteristics of the environment, Tubifex tubifex (the alternate host)...
Long-period effects of the Denali earthquake on water bodies in the Puget Lowland: Observations and modeling
A. Barberopoulou, A. Qamar, T. L. Pratt, W. P. Steele
2006, Bulletin of the Seismological Society of America (96) 519-535
Analysis of strong-motion instrument recordings in Seattle, Washington, resulting from the 2002 Mw 7.9 Denali, Alaska, earthquake reveals that amplification in the 0.2-to 1.0-Hz frequency band is largely governed by the shallow sediments both inside and outside the sedimentary basins beneath the Puget Lowland. Sites above the deep sedimentary strata...
Importance of recent shifts in soil thermal dynamics on growing season length, productivity, and carbon sequestration in terrestrial high-latitude ecosystems
E.S. Euskirchen, A. D. McGuire, D. W. Kicklighter, Q. Zhuang, Joy S. Clein, R.J. Dargaville, D.G. Dye, J.S. Kimball, K.C. McDonald, J. M. Melillo, V.E. Romanovsky, N.V. Smith
2006, Global Change Biology (12) 731-750
In terrestrial high-latitude regions, observations indicate recent changes in snow cover, permafrost, and soil freeze-thaw transitions due to climate change. These modifications may result in temporal shifts in the growing season and the associated rates of terrestrial productivity. Changes in productivity will influence the ability of these ecosystems to sequester...
Studying toxicity
A. Elkus, L. LeBlanc, C. Kim, R. Van Beneden, G. Mayer
2006, International Water Power and Dam Construction (58) 30-32
With funding from the George Mitchell Center for the Environment at the University of Maine, a team of scientists used a simple laboratory-based sediment resuspension design, and two well-established aquatic toxicology models, fathead minnows (Pimephales promelas) and zebrafish (Danio rerio), to evaluate if resuspension of Penobscot river sediment significantly elevates...
The large-scale distribution and internal geometry of the fall 2000 Po River flood deposit: Evidence from digital X-radiography
R. A. Wheatcroft, A.W. Stevens, L.M. Hunt, T.G. Milligan
2006, Continental Shelf Research (26) 499-516
Event-response coring on the Po River prodelta (northern Adriatic Sea) coupled with shipboard digital X-radiography, resistivity profiling, and grain-size analyses permitted documentation of the initial distribution and physical properties of the October 2000 flood deposit. The digital X-radiography system comprises a constant-potential X-ray source and an amorphous silicon imager with...
Effects of stream enclosures on drifting invertebrates and fish growth
J. K. H. Zimmerman, B. Vondracek
2006, Journal of the North American Benthological Society (25) 453-464
Stream ecologists often use enclosure experiments to investigate predator-prey interactions and competition within and among fish species. The design of enclosures, manipulation of species densities, and method of replication may influence experimental results. We designed an experiment with enclosure cages (1 m2, 6-mm mesh) to examine the relative influence of...
Research article: Watershed management councils and scientific models: Using diffusion literature to explain adoption
M.D. King, N. Burkardt, B. T. Clark
2006, Environmental Practice (8) 125-134
Recent literature on the diffusion of innovations concentrates either specifically on public adoption of policy, where social or environmental conditions are the dependent variables for adoption, or on private adoption of an innovation, where emphasis is placed on the characteristics of the innovation itself. This article uses both the policy...
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...
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...
Simulation of reactive transport of uranium(VI) in groundwater with variable chemical conditions
Gary P. Curtis, James A. Davis, David L. Naftz
2006, Water Resources Research (42)
The reactive transport of U(VI) in a shallow alluvial aquifer beneath a former U(VI) mill located near Naturita, CO, was simulated using a surface complexation model (SCM) to describe U(VI) adsorption. The groundwater had variable U(VI) concentrations (0.01–20 μM), variable alkalinity (2.5–18 meq/L), and a nearly constant pH equal to...
North Kona slump: Submarine flank failure during the early(?) tholeiitic shield stage of Hualalai Volcano
P. W. Lipman, M.L. Coombs
2006, Journal of Volcanology and Geothermal Research (151) 189-216
The North Kona slump is an elliptical region, about 20 by 60 km (1000-km2 area), of multiple, geometrically intricate benches and scarps, mostly at water depths of 2000–4500 m, on the west flank of Hualalai Volcano. Two dives up steep scarps in the slump area were made in September 2001,...
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-...
Inverse modeling for seawater intrusion in coastal aquifers: Insights about parameter sensitivities, variances, correlations and estimation procedures derived from the Henry problem
E. Sanz, C.I. Voss
2006, Advances in Water Resources (29) 439-457
Inverse modeling studies employing data collected from the classic Henry seawater intrusion problem give insight into several important aspects of inverse modeling of seawater intrusion problems and effective measurement strategies for estimation of parameters for seawater intrusion. Despite the simplicity of the Henry problem, it embodies the behavior of a...
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...
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...
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...
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...
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...
Estimating hydraulic properties using a moving-model approach and multiple aquifer tests
K. J. Halford, D. Yobbi
2006, Ground Water (44) 284-291
A new method was developed for characterizing geohydrologic columns that extended >600 m deep at sites with as many as six discrete aquifers. This method was applied at 12 sites within the Southwest Florida Water Management District. Sites typically were equipped with multiple production wells, one for each aquifer and...
Summer food habits and trophic overlap of roundtail chub and creek chub in Muddy Creek, Wyoming
M.C. Quist, M.R. Bower, W.A. Hubert
2006, Southwestern Naturalist (51) 22-27
Native fishes of the Upper Colorado River Basin have experienced substantial declines in abundance and distribution, and are extirpated from most of Wyoming. Muddy Creek, in south-central Wyoming (Little Snake River watershed), contains sympatric populations of native roundtail chub (Gila robusta), bluehead sucker, (Catostomus discobolus), and flannelmouth sucker (C. tatipinnis),...
The Cenozoic palaeoenvironment of the Arctic Ocean
K. Moran, J. Backman, H. Brinkhuis, S.C. Clemens, Thomas M. Cronin, G.R. Dickens, F. Eynaud, J. Gattacceca, M. Jakobsson, R.W. Jordan, M. Kaminski, J. King, N. Koc, A. Krylov, N. Martinez, J. Matthiessen, D. McInroy, T.C. Moore, J. Onodera, M. O’Regan, H. Palike, B. Rea, D. Rio, T. Sakamoto, D. C. Smith, R. Stein, John K. St, I. Suto, N. Suzuki, K. Takahashi, M. E. Watanabe, M. Yamamoto, J. Farrell, M. Frank, P. Kubik, W. Jokat, Y. Kristoffersen
2006, Nature (441) 601-605
The history of the Arctic Ocean during the Cenozoic era (0–65 million years ago) is largely unknown from direct evidence. Here we present a Cenozoic palaeoceanographic record constructed from >400 m of sediment core from a recent drilling expedition to the Lomonosov ridge in the Arctic Ocean. Our record shows a...
Glacial Lake Musselshell: Late Wisconsin slackwater on the Laurentide ice margin in central Montana, USA
N.K. Davis, W. W. Locke III, K. L. Pierce, R.C. Finkel
2006, Geomorphology (75) 330-345
Cosmogenic surface exposure ages of glacial boulders deposited in ice-marginal Lake Musselshell suggest that the lake existed between 20 and 11.5 ka during the Late Wisconsin glacial stage (MIS 2), rather than during the Late Illinoian stage (MIS 6) as traditionally thought. The altitude of the highest ice-rafted boulders and...
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...
