Evaluating the source of streamwater nitrate using δ15N and δ18O in nitrate in two watersheds in New Hampshire, USA
Linda H. Pardo, Carol Kendall, Jennifer Pett-Ridge, Cecily C.Y. Chang
2004, Hydrological Processes (18) 2699-2712
The natural abundance of nitrogen and oxygen isotopes in nitrate can be a powerful tool for identifying the source of nitrate in streamwater in forested watersheds, because the two main sources of nitrate, atmospheric deposition and microbial nitrification, have distinct δ18O values. Using a simple mixing model, we estimated the...
Survival, cause-specific mortality, and harvesting of male black-tailed deer in washington
Louis C. Bender, G.A. Schirato, R.D. Spencer, K.R. McAllister, B.L. Murphie
2004, Journal of Wildlife Management (68) 870-878
We determined survival rates, causes of mortality, and documented impacts of harvest on ???1.5-year-old male (hereafter, male) Columbian black-tailed deer (Odocoileus hemionus columbianus) in 2 Washington, USA, game management units (GMUs; Skookumchuck and Snoqualmie) characterized by different hunting-season structures. We monitored 66 males (n = 28 and 38 annually) in...
The application of an integrated biogeochemical model (PnET-BGC) to five forested watersheds in the Adirondack and Catskill regions of New York
Chen LiJun, C. T. Driscoll, S. Gbondo-Tugbawa, M.J. Mitchell, Peter S. Murdoch
2004, Hydrological Processes (18) 2631-2650
PnET-BGC is an integrated biogeochemical model formulated to simulate the response of soil and surface waters in northern forest ecosystems to changes in atmospheric deposition and land disturbances. In this study, the model was applied to five intensive study sites in the Adirondack and Catskill regions of New York. Four...
Field investigation into unsaturated flow and transport in a fault: Model analyses
H.-H. Liu, R. Salve, J.-S. Wang, G.S. Bodvarsson, D. Hudson
2004, Journal of Contaminant Hydrology (74) 39-59
Results of a fault test performed in the unsaturated zone of Yucca Mountain, Nevada, were analyzed using a three-dimensional numerical model. The fault was explicitly represented as a discrete feature and the surrounding rock was treated as a dual-continuum (fracture-matrix) system. Model calibration against seepage and water-travel-velocity data suggests that...
Can site response be predicted?
D.M. Boore
2004, Journal of Earthquake Engineering (8) 1-41
Large modifications of seismic waves are produced by variations of material properties near the Earth's surface and by both surface and buried topography. These modifications, usually referred to as "site response", in general lead to larger motions on soil sites than on rock-like sites. Because the soil amplifications can be...
The role of density dependence in growth patterns of ceded territory walleye populations of northern Wisconsin: Effects of changing management regimes
G.G. Sass, S.W. Hewett, T.D. Beard Jr., A.H. Fayram, J.F. Kitchell
2004, North American Journal of Fisheries Management (24) 1262-1278
We assessed density-related changes in growth of walleye Sander vitreus in the ceded territory of northern Wisconsin from 1977 to 1999. We used asymptotic length (Lz), growth rate near t0 (??), and body condition as measures of walleye growth to determine the relationship between growth and density. Among lakes, there...
Probabilistic seismic hazard analysis for Sumatra, Indonesia and across the Southern Malaysian Peninsula
M.D. Petersen, J. Dewey, S. Hartzell, C. Mueller, S. Harmsen, A.D. Frankel, K. Rukstales
2004, Tectonophysics (390) 141-158
The ground motion hazard for Sumatra and the Malaysian peninsula is calculated in a probabilistic framework, using procedures developed for the US National Seismic Hazard Maps. We constructed regional earthquake source models and used standard published and modified attenuation equations to calculate peak ground acceleration at 2% and 10% probability...
A conceptual model for river water and sediment dispersal in the Santa Barbara Channel, California
J.A. Warrick, L.A.K. Mertes, L. Washburn, D.A. Siegel
2004, Continental Shelf Research (24) 2029-2043
The ephemeral Santa Clara River delivers large amounts of freshwater and sediment to the eastern Santa Barbara Channel during brief, episodic discharge events. This discharge into the channel was characterized here with shipboard measurements during floods of 1997 and 1998. Within approximately 1-km of the river mouth, the river discharge...
Quantitative mineralogy of the Yukon River system: Changes with reach and season, and determining sediment provenance
D. D. Eberl
2004, American Mineralogist (89) 1784-1794
The mineralogy of Yukon River basin sediment has been studied by quantitative X-ray diffraction. Bed, beach, bar, and suspended sediments were analyzed using the RockJock computer program. The bed sediments were collected from the main stem and from selected tributaries during a single trip down river, from Whitehorse to the...
Mg/Ca, Sr/Ca, and stable isotopes in modern and Holocene Protothaca staminea shells from a northern California coastal upwelling region
R.K. Takesue, A. VanGeen
2004, Geochimica et Cosmochimica Acta (68) 3845-3861
This study explores the potential of intertidal Protothaca staminea shells as high-resolution geochemical archives of environmental change in a coastal upwelling region. Mg/Ca and Sr/Ca ratios were analyzed by excimer laser ablation-inductively coupled plasma mass spectrometry (LA-ICP-MS) at sub-weekly temporal resolution in shells growing ???1 mm per month. Growth patterns...
Volatile organic compounds in ground water from rural private wells, 1986 to 1999
M.J. Moran, W.W. Lapham, B.L. Rowe, J.S. Zogorski
2004, Journal of the American Water Resources Association (40) 1141-1157
The U.S. Geological Survey (USGS) collected or compiled data on volatile organic compounds (VOCs) in samples of untreated ground water from 1,926 rural private wells during 1986 to 1999. At least one VOC was detected in 12 percent of samples from rural private wells. Individual VOCs were not commonly detected...
Landscape context moderates edge effects: Nesting success of wood thrushes in Central New York
Melanie J.L. Driscoll, T.M. Donovan
2004, Conservation Biology (18) 1330-1338
Despite two decades of research into the effects of habitat fragmentation and edges on nesting birds, critical information about how edges affect the success of natural nests of Neotropical migratory songbirds breeding in heterogeneous landscapes is still missing. We studied abundance and nesting success in Wood Thrushes (Hylocichla mustelina) breeding...
A GIS analysis of suitability for construction aggregate recycling sites using regional transportation network and population density features
G.R. Robinson Jr., K. E. Kapo
2004, Resources, Conservation and Recycling (42) 351-365
Aggregate is used in road and building construction to provide bulk, strength, support, and wear resistance. Reclaimed asphalt pavement (RAP) and reclaimed Portland cement concrete (RPCC) are abundant and available sources of recycled aggregate. In this paper, current aggregate production operations in Virginia, Maryland, and the District of Columbia are...
Fish populations associated with habitat-modified piers and natural woody debris in Piedmont Carolina reservoirs
R.D. Barwick, T.J. Kwak, R.L. Noble, D.H. Barwick
2004, North American Journal of Fisheries Management (24) 1120-1133
A primary concern associated with reservoir shoreline residential development is reduction of littoral habitat complexity and diversity. One potential approach to compensate for this is the deployment of artificial-habitat modules under existing piers, but the benefit of this practice has not been demonstrated. To evaluate the effect of pier habitat...
Investigation of differences between field and laboratory pH measurements of national atmospheric deposition program/national trends network precipitation samples
N. Latysh, J. Gordon
2004, Water, Air, & Soil Pollution (154) 249-270
A study was undertaken to investigate differences between laboratory and field pH measurements for precipitation samples collected from 135 weekly precipitation-monitoring sites in the National Trends Network from 12/30/1986 to 12/28/1999. Differences in pH between field and laboratory measurements occurred for 96% of samples collected during this time period. Differences...
Sensitivity analysis of seismic hazard for the northwestern portion of the state of Gujarat, India
M.D. Petersen, B.K. Rastogi, E.S. Schweig, S. C. Harmsen, J.S. Gomberg
2004, Tectonophysics (390) 105-115
We test the sensitivity of seismic hazard to three fault source models for the northwestern portion of Gujarat, India. The models incorporate different characteristic earthquake magnitudes on three faults with individual recurrence intervals of either 800 or 1600 years. These recurrence intervals imply that large earthquakes occur on one of...
Late Pleistocene to Holocene environmental changes as recorded in the sulfur geochemistry of coastal plain sediments, southwestern Taiwan
Y.-G. Chen, J.C.-L. Liu, Y.-N. Shieh, T.-K. Liu
2004, Journal of Asian Earth Sciences (24) 213-224
A core, drilled at San-liao-wan in the southwestern coastal plain of Taiwan, has been analyzed for total sulfur contents, isotopic values, as well as ratios of pyritic sulfur to organic carbon. Our results demonstrate a close relationship between late Pleistocene sea-level change and the proxies generated in this study. The...
Comparison of in situ uranium KD values with a laboratory determined surface complexation model
G.P. Curtis, P. Fox, M. Kohler, J.A. Davis
2004, Applied Geochemistry (19) 1643-1653
Reactive solute transport simulations in groundwater require a large number of parameters to describe hydrologic and chemical reaction processes. Appropriate methods for determining chemical reaction parameters required for reactive solute transport simulations are still under investigation. This work compares U(VI) distribution coefficients (i.e. KD values) measured under field conditions with...
Selenium in water, sediment, plants, invertebrates, and fish in the Blackfoot River drainage
S. J. Hamilton, K.J. Buhl
2004, Water, Air, & Soil Pollution (159) 3-34
Nine stream sites in the Blackfoot River watershed in southeastern Idaho were sampled in September 2000 for water, surficial sediment, aquatic plants, aquatic invertebrates, and fish. Selenium was measured in these aquatic ecosystem components, and a hazard assessment was performed on the data. Water quality characteristics such as pH, hardness,...
Source parameters and rupture velocities of microearthquakes in western Nagano, Japan, determined using stopping phases
K. Imanishi, M. Takeo, W.L. Ellsworth, H. Ito, T. Matsuzawa, Y. Kuwahara, Y. Iio, S. Horiuchi, S. Ohmi
2004, Bulletin of the Seismological Society of America (94) 1762-1780
We use an inversion method based on stopping phases (Imanishi and Takeo, 2002) to estimate the source dimension, ellipticity, and rupture velocity of microearthquakes and investigate the scaling relationships between source parameters. We studied 25 earthquakes, ranging in size from M 1.3 to M 2.7, that occurred between May and...
Origin of the Red Dog Zn-Pb-Ag deposits, Brooks Range, Alaska: Evidence from regional Pb and Sr isotope sources
R. A. Ayuso, K.D. Kelley, D. L. Leach, L. E. Young, J. F. Slack, G. Wandless, A.M. Lyon, J.L. Dillingham
2004, Economic Geology (99) 1533-1553
Pb and Sr isotope data were obtained on the shale-hosted Zn-Pb-Ag Red Dog deposits (Qanaiyaq, Main, Aqqaluk, and Paalaaq), other shale-hosted deposits near Red Dog, and Zn-Pb-Ag sulfide and barite deposits in the western and central Brooks Range. The Red Dog deposits and other shale-hosted Zn-Pb-Ag deposits near Red Dog...
Lattice-Boltzmann simulation of coalescence-driven island coarsening
H. Basagaoglu, C.T. Green, P. Meakin, B.J. McCoy
2004, Journal of Chemical Physics (121) 7987-7995
The first-order phase separation in a thin fluid film was simulated using a two-dimensional lattice-Boltzman model (LBM) with fluid-fluid interactions. The effects of the domain size on the intermediate asymptotic island size distribution were also discussed. It was observed that the overall process is dominated by coalescence which is independent...
Effects of nutrient enrichment on the decomposition of wood and associated microbial activity in streams
V. Gulis, A.D. Rosemond, K. Suberkropp, H.S. Weyers, J.P. Benstead
2004, Freshwater Biology (49) 1437-1447
1. We determined the effects of nutrient enrichment on wood decomposition rates and microbial activity during a 3-year study in two headwater streams at Coweeta Hydrologic Laboratory, NC, U.S.A. After a 1-year pretreatment period, one of the streams was continuously enriched with inorganic nutrients (nitrogen and phosphorus) for 2 years...
Vulnerability of drinking-water wells in La Crosse, Wisconsin, to enteric-virus contamination from surface water contributions
M. A. Borchardt, N.L. Haas, R. J. Hunt
2004, Applied and Environmental Microbiology (70) 5937-5946
Human enteric viruses can contaminate municipal drinking-water wells, but few studies have examined the routes by which viruses enter these wells. In the present study, the objective was to monitor the municipal wells of La Crosse, Wisconsin, for enteric viruses and determine whether the amount of Mississippi River water infiltrating...
Do predators influence the distribution of age-0 kokanee in a Colorado Reservoir?
J.M. Hardiman, B. M. Johnson, P.J. Martinez
2004, Transactions of the American Fisheries Society (133) 1366-1378
Seasonal changes in reservoir conditions such as productivity, light, and temperature create spatiotemporal variation in habitat that may segregate or aggregate predators and prey, producing implications for the distribution, growth, and survival of fishes. We used hydroacoustics to document the diel vertical distribution of age-0 kokanee Oncorhynchus nerka relative to...
