Vegetation responses to dam removal
Patrick B. Shafroth, Jonathan M. Friedman, Gregor T. Auble, Michael L. Scott
2004, Arid Ecosystems (10) 95-105
No abstract available....
Trophic performance of Oncorhynchus mykiss in tributaries of the south fork Trinity River, northern California
S.G. McCarthy
2004, Thesis
No abstract available ...
Population characteristics of Siren lacertina and Amphiuma means in north Florida
K. Sorensen
2004, Southeastern Naturalist (3) 249-258
Abstract not supplied at this time...
Solar and temporal effects on Escherichia coli concentration at a Lake Michigan swimming beach
Richard L. Whitman, Meredith B. Nevers, Ginger C. Korinek, Muruleedhara N. Byappanahalli
2004, Applied and Environmental Microbiology (70) 4276-4285
Studies on solar inactivation of Escherichia coli in freshwater and in situ have been limited. At 63rd St. Beach, Chicago, Ill., factors influencing the daily periodicity of culturable E. coli, particularly insolation, were examined. Water samples for E. coli analysis were collected twice daily between April and September 2000 three times a week along five...
Upper crustal structure from the Santa Monica Mountains to the Sierra Nevada, Southern California: Tomographic results from the Los Angeles Regional Seismic Experiment, Phase II (LARSE II)
W. J. Lutter, G. S. Fuis, T. Ryberg, D. A. Okaya, R.W. Clayton, P.M. Davis, C. Prodehl, J.M. Murphy, V.E. Langenheim, M.L. Benthien, N. J. Godfrey, N.I. Christensen, K. Thygesen, C.H. Thurber, G. Simila, Gordon R. Keller
2004, Bulletin of the Seismological Society of America (94) 619-632
In 1999, the U.S. Geological Survey and the Southern California Earthquake Center (SCEC) collected refraction and low-fold reflection data along a 150-km-long corridor extending from the Santa Monica Mountains northward to the Sierra Nevada. This profile was part of the second phase of the Los Angeles Region Seismic Experiment (LARSE...
Numerical studies of gas production from several CH4 hydrate zones at the Mallik site, Mackenzie Delta, Canada
G. J. Moridis, T. S. Collett, S.R. Dallimore, T. Satoh, S. Hancock, B. Weatherill
2004, Journal of Petroleum Science and Engineering (43) 219-238
The Mallik site represents an onshore permafrost-associated gas hydrate accumulation in the Mackenzie Delta, Northwest Territories, Canada. A gas hydrate research well was drilled at the site in 1998. The objective of this study is the analysis of various gas production scenarios from five methane hydrate-bearing zones at the Mallik...
Light dependence of selenium uptake by phytoplankton and implications for predicting selenium incorporation into food webs
S.B. Baines, N.S. Fisher, M.A. Doblin, G.A. Cutter, L.S. Cutter, B. Cole
2004, Limnology and Oceanography (49) 566-578
The potentially toxic element selenium is first concentrated from solution to a large but highly variable degree by algae and bacteria before being passed on to consumers. The large loads of abiotic and detrital suspended particles often present in rivers and estuaries may obscure spatial and temporal patterns in Se...
Influence of forest management on headwater stream amphibians at multiple spatial scales
Margo Stoddard, John P. Hayes, Janet L. Erickson
2004, Fact Sheet 2004-3018
Background Amphibians are important components of headwater streams in forest ecosystems of the Pacific Northwest (PNW). They comprise the highest vertebrate biomass and density in these systems and are integral to trophic dynamics both as prey and as predators. The most commonly encountered amphibians in PNW headwater streams include the Pacific...
Consequences of forest clear-cuts for native and nonindigenous ants (Hymenoptera: Formicidae)
J.A. Zettler, M.D. Taylor, Craig R. Allen, T.P. Spira
2004, Annals of the Entomological Society of America (97) 513-518
Currently, the southern United States produces more timber than any other region in the world. Entire timber stands are removed through a harvesting method called clear-cutting. This common forestry practice may lead to the replacement of native ant communities with invasive, nonindigenous species. In four deciduous forest sites in South...
Hydrological effects of soil water repellency: On spatial and temporal uncertainties
S.H. Doerr, J. A. Moody
2004, Hydrological Processes (18) 829-832
[No abstract available]...
Atmospheric wet deposition of trace elements to a suburban environment, Reston, Virginia, USA
Kathryn M. Conko, Karen C. Rice, Margaret M. Kennedy
2004, Atmospheric Environment (38) 4025-4033
Wet deposition from a suburban area in Reston, Virginia was collected during 1998 and analyzed to assess the anion and trace-element concentrations and depositions. Suburban Reston, approximately 26 km west of Washington, DC, is densely populated and heavily developed. Wet deposition was collected bi-weekly in an automated collector using trace-element clean...
Interpretation of concentration‐discharge patterns in acid‐neutralizing capacity during storm flow in three small, forested catchments in Shenandoah National Park, Virginia
Karen C. Rice, Jeffrey G. Chanat, George M. Hornberger, James R. Webb
2004, Water Resources Research (40)
Episodic concentration‐discharge (c‐Q) plots are a popular tool for interpreting the hydrochemical response of small, forested catchments. Application of the method involves assuming an underlying conceptual model of runoff processes and comparing observed c‐Q looping patterns with those predicted by the model. We analyzed and interpreted c‐Q plots of acid‐neutralizing capacity (ANC) for 133...
Rehabilitation of a lignite mine-disturbed area in the Indian Desert
K.D. Sharma, P. Kumar, L. P. Gough, J.R. SanFilipo
2004, Land Degradation and Development (15) 163-176
Extensive lignite mining in the Indian (Thar) Desert commenced within the past decade. Accompanying extraction of this valuable resource there have been visible, important environmental impacts. The resultant land degradation has prompted concern from both public and regulatory bodies. This research assesses the success of rehabilitation plans implemented to revegetate...
Determinants of reproductive costs in the long-lived Black-legged Kittiwake: A multiyear experiment
Gregory H. Golet, Joel A. Schmutz, David B. Irons, James A. Estes
2004, Ecological Monographs (74) 353-372
We studied reproductive costs of Black-legged Kittiwakes (Rissa tridactyla) in Prince William Sound, Alaska (USA) by removing entire clutches from randomly selected nests over four successive years, and then contrasting survival and fecundity of adults from manipulated and unmanipulated nests in each subsequent year. To elucidate mechanisms that lead...
First-year growth, condition, and size-selective winter mortality of freshwater drum in the lower Missouri River
P.J. Braaten, C.S. Guy
2004, Transactions of the American Fisheries Society (133) 385-398
We compared first-year growth and relative condition (Kn) of the 1997 and 1998 year-classes of freshwater drum Aplodinotus grunniens among three sites in a 235-km reach of the channelized Missouri River and tested for the occurrence of size-selective overwinter mortality during the first winter. Prewinter mean length was 15 mm...
Gasoline-related organics in Lake Tahoe before and after prohibition of carbureted two-stroke engines
M.S. Lico
2004, Lake and Reservoir Management (20) 164-174
On June 1, 1999, carbureted two-stroke engines were banned on waters within the Lake Tahoe Basin of California and Nevada. The main gasoline components MTBE (methyl tert-butyl ether) and BTEX (benzene, toluene, ethylbenzene, and xylenes) were present at detectable concentrations in all samples taken from Lake Tahoe during 1997–98 prior to...
US Rockies gas focus points up need for access, risk takers, infrastructure
M.R. Thomasson, P.E. Belanger, L. Cook
2004, Oil & Gas Journal (102)
The last 20 yr of the Rocky Mountains oil and gas exploration and production business have been turbulent. Most of the major companies have left; they have been replaced with, independents and small to larger private and public companies. Natural gas become the primary focus of exploration. A discussion covers...
Estimating V̄s(30) (or NEHRP site classes) from shallow velocity models (depths < 30 m)
David M. Boore
2004, Bulletin of the Seismological Society of America (94) 591-597
The average velocity to 30 m [V??s(30)] is a widely used parameter for classifying sites to predict their potential to amplify seismic shaking. In many cases, however, models of shallow shear-wave velocities, from which V??s(30) can be computed, do not extend to 30 m. If the data for these cases...
Evidence for dike emplacement beneath Iliamna Volcano, Alaska in 1996
D.C. Roman, J.A. Power, S.C. Moran, K. V. Cashman, M.P. Doukas, C.A. Neal, T.M. Gerlach
2004, Journal of Volcanology and Geothermal Research (130) 265-284
Two earthquake swarms, comprising 88 and 2833 locatable events, occurred beneath Iliamna Volcano, Alaska, in May and August of 1996. Swarm earthquakes ranged in magnitude from -0.9 to 3.3. Increases in SO2 and CO2 emissions detected during the fall of 1996 were coincident with the second swarm. No other physical...
Winter habitat use by cutthroat trout in the Snake River near Jackson, Wyoming
D.D. Harper, A.M. Farag
2004, Transactions of the American Fisheries Society (133) 15-25
Winter habitat use by Yellowstone cutthroat trout Oncorhynchus clarki bouvieri was monitored with radiotelemetry during November-March 1998-2001 in channelized and unaltered sections of the Snake River near Jackson, Wyoming. The use of run and off-channel pool habitat was significantly correlated to water temperature; run use was most frequent when mean...
An alternative approach to detection of length-related biases in standard weight equations
K.G. Gerow, W.A. Hubert, R. C. Anderson-Sprecher
2004, North American Journal of Fisheries Management (24) 903-910
We propose a new method for assessing length-related biases in standard weight (Ws) equations computed by the regression-line-percentile method. We evaluated the performance of the new method relative to two previous methods for assessing length-related biases using 15 data sets from which W s equations have been computed. The new...
Importance of the Vadose Zone in analyses of unconfined aquifer tests
A.F. Moench
2004, Ground Water (42) 223-233
Analytical models commonly used to interpret unconfined aquifer tests have been based on upper-boundary (water table) conditions that do not adequately address effects of time-varying drainage from the vadose zone. As a result, measured and simulated drawdown data may not agree and hydraulic parameters may be inaccurately estimated. A 72-hour...
Seismographs, sensors, and satellites: Better technology for safer communities
C.G. Groat
2004, Technology in Society (26) 169-179
In the past 25 years, our ability to measure, monitor, and model the processes that lead to natural disasters has increased dramatically. Equally important has been the improvement in our technological capability to communicate information about hazards to those whose lives may be affected. These innovations in tracking and communicating...
Evidence of long-term seasonal climate forcing in rhizolith isotopes during the last glaciation
Hongfang Wang, S.H. Ambrose, B.W. Fouke
2004, Geophysical Research Letters (31)
High density carbonate rhizoliths were found from a loess-paleosol succession from the late Wisconsin period (21-11 ka) in Illinois. Their morphology shows that they formed in a close contact with living and decomposing roots, suggesting a root/microbial respiration origin. Carbon (??13C) and oxygen (??18O) isotopic analyses were performed on 36...
Strain accumulation across the Coast Ranges at the latitude of San Francisco, 1994-2000
J.C. Savage, Weijun Gan, W.H. Prescott, J. L. Svarc
2004, Journal of Geophysical Research B: Solid Earth (109)
A 66-monument geodetic array spanning the Coast Ranges near San Francisco has been surveyed more than eight times by GIPS between late 1993 and early 2001. The measured horizontal velocities of the monuments are well represented by uniform, right-lateral, simple shear parallel to N29°W. (The local strike of the San...
