Effects of anthropogenic fragmentation and livestock grazing on western riparian bird communities
J.J. Tewksbury, A.E. Black, N. Nur, V.A. Saab, B.D. Logan, D.S. Dobkin
2002, Conference Paper, Studies in Avian Biology
Deciduous vegetation along streams and rivers provides breeding habitat to more bird species than any other plant community in the West, yet many riparian areas are heavily grazed by cattle and surrounded by increasingly developed landscapes. The combination of cattle grazing and landscape alteration (habitat loss and fragmentation) are thought...
Interactions among zebra mussel shells, invertebrate prey, and Eurasian ruffe or yellow perch
Cynthia S. Kolar, Aimee H. Fullerton, K. M. Martin, Gary A Lamberti
2002, Journal of Great Lakes Research (28) 664-673
The exotic zebra mussel, Dreissena polymorpha, is established in all of the Laurentian Great Lakes and may affect benthivorous fishes by increasing the complexity of benthic substrates and changing energy flow patterns within the food web. Native yellow perch, Perca flavescens, and the nonindigenous Eurasian ruffe, Gymnocephalus cernuus, are benthivores that may compete...
Evaluation of passive diffusion bag and dialysis samplers in selected wells at Hickam Air Force Base, Hawaii, July 2001
Don A. Vroblesky, Tasha Pravecek
2002, Water-Resources Investigations Report 2002-4159
Field comparisons of chemical concentrations obtained from dialysis samplers, passive diffusion bag samplers, and low-flow samplers showed generally close agreement in most of the 13 wells tested during July 2001 at Hickam Air Force Base, Hawaii. The data for chloride, sulfate, iron, alkalinity, arsenic, and methane appear to show that...
Historical changes in lake ice-out dates as indicators of climate change in New England, 1850-2000
G.A. Hodgkins, Ivan James C. , I. C., T.G. Huntington
2002, International Journal of Climatology (22) 1819-1827
Various studies have shown that changes over time in spring ice-out dates can be used as indicators of climate change. Ice-out dates from 29 lakes in New England (USA) with 64 to 163 years of record were assembled and analysed for this study. Ice-out dates have become significantly earlier in...
Modeling enhanced in situ denitrification in groundwater
M.W. Killingstad, M.A. Widdowson, R. L. Smith
2002, Journal of Environmental Engineering (128) 491-504
A two-dimensional numerical solute transport model was developed for simulating an enhanced in situ denitrification experiment performed in a nitrate-contaminated aquifer on Cape Cod, Massachusetts. In this experiment, formate (HCOO-)">(HCOO-) was injected for a period of 26 days into the carbon-limited aquifer to stimulate denitrification....
Rates and timing of earth surface processes from in situ-produced cosmogenic Be-10
Paul R. Bierman, Marc W. Caffee, P. Thompson Davis, K. Marsella, Milan Pavich, P. Colgan, D. Mickelson, J. Larsen
2002, Reviews in Mineralogy and Geochemistry (50) 147-205
No abstract available....
Nitrogen in rock: Occurrences and biogeochemical implications
J.M. Holloway, R.A. Dahlgren
2002, Global Biogeochemical Cycles (16) 65-1-65-17
There is a growing interest in the role of bedrock in global nitrogen cycling and potential for increased ecosystem sensitivity to human impacts in terrains with elevated background nitrogen concentrations. Nitrogen-bearing rocks are globally distributed and comprise a potentially large pool of nitrogen in nutrient cycling that is frequently neglected...
Related magma-ice interactions: Possible origins of chasmata, chaos, and surface materials in Xanthe, Margaritifer, Meridiani Terrae, Mars
M. G. Chapman, K. L. Tanaka
2002, Icarus (155) 324-339
We examine here the close spatial and temporal associations among several unique features of Xanthe and Margaritifer Terrae, specifically the Valles Marineris troughs or chasmata and their interior deposits, chaotic terrain, the circum-Chryse outflow channels, and the subdued cratered material that covers Xanthe, Margaritifer, and Meridiani Terrae. Though previous hypotheses...
A terrain-based paired-site sampling design to assess biodiversity losses from eastern hemlock decline
J.A. Young, D. R. Smith, C.D. Snyder, D. P. Lemarie
2002, Environmental Monitoring and Assessment (76) 167-183
Biodiversity surveys are often hampered by the inability to control extraneous sources of variability introduced into comparisons of populations across a heterogenous landscape. If not specifically accounted for a priori, this noise can weaken comparisons between sites, and can make it difficult to draw inferences about specific ecological processes. We...
Heavy mineral provinces of the Palos Verdes margin, southern California
F. L. Wong
2002, Continental Shelf Research (22) 899-910
Natural sources of sediment for the Palos Verdes margin, southern California, have been augmented by effluent discharged from Los Angeles County Sanitation District's sewage-treatment facility and by the reactivation of the Portuguese Bend landslide. Heavy minerals in very fine and fine sand (63-250 ??m) from beach and shelf sites off...
Statistical characteristics of xenoliths in the Antioch kimberlite pipe, Marshall County, northeastern Kansas
S. Kotov, Pieter Berendsen
2002, Natural Resources Research (11) 289-297
Geometrical characteristics of xenoliths in the Antioch kimberlite pipe have been considered in statistical terms. A method of conversion of 2D intersections to 3D dimensions was used. It has been shown that the Rosin-Rammler distribution of mass leads to the Weibull distribution of sizes, whereas a fractal distribution of sizes...
Cirsium nuttallii (Asteraceae: Cynareae) new to North Carolina and an illustrated key to southeastern congeners
A. Krings, R. Westbrooks, J. Lloyd
2002, SIDA, Contributions to Botany (20) 845-848
Cirsium nuttallii (Asteraceae) is documented for North Carolina. The species had previously been known from Florida to South Carolina and from disjunct populations in Virginia. An illustrated key is provided to aid others in the diagnosis of Cirsium in North Carolina and the southeast....
Hydrogeologic processes in saline systems: Playas, sabkhas, and saline lakes
Y. Yechieli, W.W. Wood
2002, Earth-Science Reviews (58) 343-365
Pans, playas, sabkhas, salinas, saline lakes, and salt flats are hydrologically similar, varying only in their boundary conditions. Thus, in evaluating geochemical processes in these systems, a generic water and solute mass-balance approach can be utilized. A conceptual model of a coastal sabkha near the Arabian Gulf is used as...
Ice-affected streamflow records using tracer-dilution discharge methods
J.P. Capesius, J.R. Sullivan, C.A. Williams, G. B. O’Neill
Wahl T.L.Pugh C.A.Oberg K.A.Vermeyen T.B.Wahl T.L.Pugh C.A.Oberg K.A.Vermeyen T.B., editor(s)
2002, Conference Paper, Hydraulic Measurements and Experimental Methods
Accurate ice-affected streamflow records are difficult to obtain for several reasons. Problems measuring stage, variable backwater conditions, access limitations in wintertime, and problems measuring flowing water under ice cover all contribute to make ice-affected streamflow records less accurate than open-channel streamflow records. The inaccuracy of ice-affected streamflow records is particularly...
Migration and habitats of diadromous Danube River sturgeons in Romania: 1998-2000
B. Kynard, R. Suciu, Martin Horgan
2002, Journal of Applied Ichthyology (18) 529-535
Upstream migrant adults of stellate sturgeon, Acipenser stellatus (10 in 1998, 43 in 1999) and Russian sturgeon, A. gueldenstaedtii (three in 1999) were captured at river km (rkm) 58-137, mostly in the spring, and tagged with acoustic tags offering a reward for return. The overharvest was revealed by tag returns...
Controls on timing and amount of right-lateral offset on the East Bay fault system, San Francisco Bay region, California
R. W. Graymer, A.M. Sarna-Wojcicki, J.P. Walker, R. J. McLaughlin, R.J. Fleck
2002, Geological Society of America Bulletin (114) 1471-1479
The distribution of offset, correlated rock units, relative position of northward- younging volcanic rocks, and distribution of units not offset together reveal the history of strike-slip deformation along the East Bay fault system. The system accumulated 175 km of right-lateral offset since 12 Ma, but of this amount, only ???25...
Drowned reefs and antecedent karst topography, Au'au channel, S.E. Hawaiian Islands
R.W. Grigg, E. E. Grossman, S.A. Earle, S.R. Gittings, D. Lott, J. McDonough
2002, Coral Reefs (21) 73-82
During the last glacial maximum (LGM), about 21,000 years ago, the Hawaiian Islands of Maui, Lanai, and Molokai were interconnected by limestone bridges, creating a super-island known as Maui-Nui. Approximately 120 m of sea-level rise during the Holocene Transgression flooded, and then drowned, these bridges separating the islands by inter-island...
Spatial scale analysis in geophysics - Integrating surface and borehole geophysics in groundwater studies
Frederick L. Paillet
V.H. Singhroy, D.T. Hansen, R.R. Pierce, A.I. Johnson, editor(s)
2002, Conference Paper, ASTM Special Technical Publication
Integration of geophysical data obtained at various scales can bridge the gap between localized data from boreholes and site-wide data from regional survey profiles. Specific approaches to such analysis include: 1) comparing geophysical measurements in boreholes with the same measurement made from the surface; 2) regressing geophysical data obtained in...
Tidal Flux Variation in the Lower Pearl River and Lake Pontchartrain Estuaries of Mississippi and Louisiana
D.P. Turnipseed
Wahl T.L.Pugh C.A.Oberg K.A.Vermeyen T.B.Wahl T.L.Pugh C.A.Oberg K.A.Vermeyen T.B., editor(s)
2002, Conference Paper, Hydraulic Measurements and Experimental Methods
Three tidal gages were constructed to collect hydraulic and water-quality properties that could be used to compute the tidal flux of the Pearl River and Lake Pontchartrain estuarine systems in Mississippi and Louisiana. The gages record continuous tidal stage, velocity, water temperature, specific conductance, and salinity, and transmit these data...
Evaluation of longitudinal dispersivity estimates from forced-gradient tracer tests in heterogeneous aquifers
C. R. Tiedeman, P. A. Hsieh
2002, IAHS-AISH Publication 168-174
Converging radial-flow and two-well tracer tests are simulated in two-dimensional aquifers to investigate the effects of heterogeneity and forced-gradient test configuration on longitudinal dispersivity (??L) estimates, and to compare ??L estimates from forced-gradient tests with ??L values that characterize solute spreading under natural-gradient flow. Results indicate that in both mildly...
Miocene extension and fault-related folding in the Highland Range, southern Nevada: A three-dimensional perspective
J. E. Faulds, E.L. Olson, S. S. Harlan, W. C. McIntosh
2002, Journal of Structural Geology (24) 861-886
The Highland Range of southern Nevada contains a major anticline and syncline that constitute the westernmost segments of the Black Mountains accommodation zone in the highly extended Colorado River extensional corridor. The folds are defined by thick tilted sections of Miocene volcanic and sedimentary strata that accumulated immediately prior to...
High-resolution characterization of chemical heterogeneity in an alluvial aquifer
M.K. Schulmeister, J.M. Healey, G.W. McCall, S. Birk, J.J. Butler
2002, Acta Universitatis Carolinae, Geologica (46) 353-355
The high-resolution capabilities of direct-push technology were exploited to develop new insights into the hydrochemistry at the margin of an alluvial aquifer. Hydrostratigraphic controls on groundwater flow and contaminant loading were revealed through the combined use of direct-push electrical conductivity (EC) logging and geochemical profiling. Vertical and lateral variations in...
Ground temperatures across the old and new roads at mile 130, Richardson highway during 1954-62
H. Jin, M.C. Brewer, R.A. Perkins
Merrill K.S.Merrill K.S., editor(s)
2002, Conference Paper, Cold Regions Engineering Cold Regions Impacts on Transportation and Infrastructure: Proceedings of the Eleventh International Conference
Year-round studies of the geothermal impacts of road construction in a "warm" permafrost area were undertaken during 1954-1962 at six road sections across the Richardson and Glenn Highways, in the vicinity of Glennallen, Alaska. As a result, significant information was obtained regarding the temperatures, and changes in temperatures, in the...
Fish assemblages and environmental variables associated with hard-rock mining in the Coeur d'Alene River basin, Idaho
Terry R. Maret, Dorene E. MacCoy
2002, Transactions of the American Fisheries Society (131) 865-884
As part of the U.S. Geological Survey's National Water Quality Assessment Program, fish assemblages, environmental variables, and associated mine densities were evaluated at 18 test and reference sites during the summer of 2000 in the Coeur d'Alene and St. Regis river basins in Idaho and Montana. Multimetric and multivariate analyses...
Success of artificial bird nests in burned Gulf Coast Chenier Plain marshes
S.W. Gabrey, B.C. Wilson, A. D. Afton
2002, Southwestern Naturalist (47) 532-538
Wildlife managers in the Gulf Coast Chenier Plain of Louisiana and Texas frequently burn marshes during winter to improve habitat for wintering waterfowl and furbearers. Such fires dramatically alter vegetation structure and cover, although such changes are generally temporary. However, if vegetation cover does not recover sufficiently by the start...
