A mass balance mercury budget for a mine-dominated lake: Clear Lake, California
T.H. Suchanek, J. Cooke, K. Keller, S. Jorgensen, P.J. Richerson, Collin A. Eagles-Smith, E.J. Harner, D.P. Adam
2009, Water, Air, & Soil Pollution (196) 51-73
The Sulphur Bank Mercury Mine (SBMM), active intermittently from 1873–1957 and now a USEPA Superfund site, was previously estimated to have contributed at least 100 metric tons (105 kg) of mercury (Hg) into the Clear Lake aquatic ecosystem. We have confirmed this minimum estimate. To better quantify the contribution of the...
Effect of species rarity on the accuracy of species distribution models for reptiles and amphibians in southern California
J. Franklin, K.E. Wejnert, S.A. Hathaway, C.J. Rochester, Robert N. Fisher
2009, Diversity and Distributions (15) 167-177
Aim: Several studies have found that more accurate predictive models of species' occurrences can be developed for rarer species; however, one recent study found the relationship between range size and model performance to be an artefact of sample prevalence, that is, the proportion of presence versus absence observations in the...
The postseismic response to the 2002 M 7.9 Denali Fault earthquake: Constraints from InSAR 2003-2005
J. Biggs, R. Burgmann, J.T. Freymueller, Z. Lu, B. Parsons, I. Ryder, G. Schmalzle, Tim Wright
2009, Geophysical Journal International (176) 353-367
InSAR is particularly sensitive to vertical displacements, which can be important in distinguishing between mechanisms responsible for the postseismic response to large earthquakes (afterslip, viscoelastic relaxation). We produce maps of the surface displacements resulting from the postseismic response to the 2002 Denali Fault earthquake, using data from the Canadian Radarsat-1...
Calibration and validation of the relative differenced Normalized Burn Ratio (RdNBR) to three measures of fire severity in the Sierra Nevada and Klamath Mountains, California, USA
J.D. Miller, E. E. Knapp, C.H. Key, C.N. Skinner, C.J. Isbell, R.M. Creasy, J.W. Sherlock
2009, Remote Sensing of Environment (113) 645-656
Multispectral satellite data have become a common tool used in the mapping of wildland fire effects. Fire severity, defined as the degree to which a site has been altered, is often the variable mapped. The Normalized Burn Ratio (NBR) used in an absolute difference change detection protocol (dNBR), has become...
Spatial-temporal patterns in Mediterranean carnivore road casualties: Consequences for mitigation
C. Grilo, J.A. Bissonette, M. Santos-Reis
2009, Biological Conservation (142) 301-313
Many carnivores have been seriously impacted by the expansion of transportation systems and networks; however we know little about carnivore response to the extent and magnitude of road mortality, or which age classes may be disproportionately impacted. Recent research has demonstrated that wildlife-vehicle-collisions (WVC) involving carnivores are modulated by temporal...
Research on the middle-of-receiver-spread assumption of the MASW method
Y. Luo, J. Xia, J. Liu, Y. Xu, Q. Liu
2009, Soil Dynamics and Earthquake Engineering (29) 71-79
The multichannel analysis of surface wave (MASW) method has been effectively used to determine near-surface shear- (S-) wave velocity. Estimating the S-wave velocity profile from Rayleigh-wave measurements is straightforward. A three-step process is required to obtain S-wave velocity profiles: acquisition of a multiple number of multichannel records along a linear...
Characterizing and predicting species distributions across environments and scales: Argentine ant occurrences in the eye of the beholder
S.B. Menke, D.A. Holway, Robert N. Fisher, W. Jetz
2009, Global Ecology and Biogeography (18) 50-63
Aim: Species distribution models (SDMs) or, more specifically, ecological niche models (ENMs) are a useful and rapidly proliferating tool in ecology and global change biology. ENMs attempt to capture associations between a species and its environment and are often used to draw biological inferences, to predict potential occurrences in unoccupied...
Assessing the sources and magnitude of diurnal nitrate variability in the San Joaquin River (California) with an in situ optical nitrate sensor and dual nitrate isotopes
Brian A. Pellerin, Bryan D. Downing, Carol Kendall, Randy A. Dahlgren, Tamara E.C. Kraus, John Franco Saraceno, Robert G. M. Spencer, Brian A. Bergamaschi
2009, Freshwater Biology (54) 376-387
1. We investigated diurnal nitrate (NO3−) concentration variability in the San Joaquin River using an in situ optical NO3− sensor and discrete sampling during a 5‐day summer period characterized by high algal productivity. Dual NO3− isotopes (δ15NNO3 and δ18ONO3) and dissolved oxygen isotopes (δ18ODO) were measured over 2 days to assess NO3− sources and biogeochemical controls over diurnal...
Hydraulic anisotropy characterization of pneumatic-fractured sediments using azimuthal self potential gradient
D.N. Wishart, L.D. Slater, D.L. Schnell, G.C. Herman
2009, Journal of Contaminant Hydrology (103) 134-144
The pneumatic fracturing technique is used to enhance the permeability and porosity of tight unconsolidated soils (e.g. clays), thereby improving the effectiveness of remediation treatments. Azimuthal self potential gradient (ASPG) surveys were performed on a compacted, unconsolidated clay block in order to evaluate their potential to delineate contaminant migration pathways...
Impacts of acidification on macroinvertebrate communities in streams of the western Adirondack Mountains, New York, USA
Barry P. Baldigo, G.B. Lawrence, R.W. Bode, H. A. Simonin, K. M. Roy, A. J. Smith
2009, Ecological Indicators (9) 226-239
Limited stream chemistry and macroinvertebrate data indicate that acidic deposition has adversely affected benthic macroinvertebrate assemblages in numerous headwater streams of the western Adirondack Mountains of New York. No studies, however, have quantified the effects that acidic deposition and acidification may have had on resident fish and macroinvertebrate communities in...
Effect of dietary α-tocopherol + ascorbic acid, selenium, and iron on oxidative stress in sub-yearling Chinook salmon (Oncorhynchus tshawytscha Walbaum)
T.L. Welker, J.L. Congleton
2009, Journal of Animal Physiology and Animal Nutrition (93) 15-25
A three-variable central composite design coupled with surface-response analysis was used to examine the effects of dietary ??-tocopherol + ascorbic acid (TOCAA), selenium (Se), and iron (Fe) on indices of oxidative stress in juvenile spring Chinook salmon. Each dietary factor was tested at five levels for a total of fifteen...
Molecular detection of native and invasive marine invertebrate larvae present in ballast and open water environmental samples collected in Puget Sound
J.B.J. Harvey, M.S. Hoy, R. J. Rodriguez
2009, Journal of Experimental Marine Biology and Ecology (369) 93-99
Non-native marine species have been and continue to be introduced into Puget Sound via several vectors including ship's ballast water. Some non-native species become invasive and negatively impact native species or near shore habitats. We present a new methodology for the development and testing of taxon specific PCR primers designed...
The speciation of aqueous zinc(II) bromide solutions to 500 °C and 900 MPa determined using Raman spectroscopy
Kenji Mibe, I-Ming Chou, Alan J. Anderson, Robert A. Mayanovic, William A. Bassett
2009, Chemical Geology (259) 48-53
A Raman spectral study was carried out on 3 solutions of varying concentration and bromide/zinc ratios. Spectra were collected at 11 different temperature-pressure conditions ranging from ambient to 500????C-0.9??GPa. Raman band assignments for zinc(II) bromide species reported in previous studies were used to determine the relative concentrations of ZnBr42-, ZnBr3-,...
Removal of organic wastewater contaminants in septic systems using advanced treatment technologies
J.D. Wilcox, J.M. Bahr, C.J. Hedman, J.D.C. Hemming, M.A.E. Barman, K. R. Bradbury
2009, Journal of Environmental Quality (38) 149-156
The detection of pharmaceuticals and other organic wastewater contaminants (OWCs) in ground water and surface-water bodies has raised concerns about the possible ecological impacts of these compounds on nontarget organisms. On-site wastewater treatment systems represent a potentially significant route of entry for organic contaminants to the environment. In this study,...
Effects of chemical immobilization on survival of African buffalo in the Kruger National Park
W.C. Oosthuizen, P.C. Cross, J.A. Bowers, C. Hay, M.R. Ebinger, P. Buss, M. Hofmeyr, E.Z. Cameron
2009, Journal of Wildlife Management (73) 149-153
Capturing, immobilizing, and fitting radiocollars are common practices in studies of large mammals, but success is based on the assumptions that captured animals are representative of the rest of the population and that the capture procedure has negligible effects. We estimated effects of chemical immobilization on mortality rates of African...
Associations between land use and Perkinsus marinus infection of eastern oysters in a high salinity, partially urbanized estuary
Brian R. Gray, David Bushek, J. Wanzer Drane, Dwayne Porter
2009, Ecotoxicology (18) 259-269
Infection levels of eastern oysters by the unicellular pathogen Perkinsus marinus have been associated with anthropogenic influences in laboratory studies. However, these relationships have been difficult to investigate in the field because anthropogenic inputs are often associated with natural influences such as freshwater inflow, which can also affect infection levels....
Transport of viruses through saturated and unsaturated columns packed with sand
R. Anders, C.V. Chrysikopoulos
2009, Transport in Porous Media (76) 121-138
Laboratory-scale virus transport experiments were conducted in columns packed with sand under saturated and unsaturated conditions. The viruses employed were the male-specific RNA coliphage, MS2, and the Salmonella typhimurium phage, PRD1. The mathematical model developed by Sim and Chrysikopoulos (Water Resour Res 36:173–179, 2000) that accounts for processes responsible for...
Relatedness and social organization of coypus in the Argentinean pampas
J.I. Tunez, M.L. Guichon, D. Centron, A.P. Henderson, C. Callahan, M.H. Cassini
2009, Molecular Ecology (18) 147-155
Behavioural and trapping studies of the social organization of coypus have suggested the occurrence of kin groups and a polygynous mating system. We used 16 microsatellite markers to analyse parentage and relatedness relationships in two populations (J??uregui and Villa Ruiz) in the Argentinean Pampas. At J??uregui, a dominant male monopolized...
Interactions among wildland fires in a long-established Sierra Nevada natural fire area
B.M. Collins, J.D. Miller, A. E. Thode, M. Kelly, J. W. van Wagtendonk, S.L. Stephens
2009, Ecosystems (12) 114-128
We investigate interactions between successive naturally occurring fires, and assess to what extent the environments in which fires burn influence these interactions. Using mapped fire perimeters and satellite-based estimates of post-fire effects (referred to hereafter as fire severity) for 19 fires burning relatively freely over a 31-year period, we demonstrate...
Calibration of an estuarine sediment transport model to sediment fluxes as an intermediate step for simulation of geomorphic evolution
N. K. Ganju, D. H. Schoellhamer
2009, Continental Shelf Research (29) 148-158
Modeling geomorphic evolution in estuaries is necessary to model the fate of legacy contaminants in the bed sediment and the effect of climate change, watershed alterations, sea level rise, construction projects, and restoration efforts. Coupled hydrodynamic and sediment transport models used for this purpose typically are calibrated to water level,...
A shift in the dominant toxin-producing algal species in central California alters phycotoxins in food webs
R. Jester, K. Lefebvre, G. Langlois, V. Vigilant, K. Baugh, M.W. Silver
2009, Harmful Algae (8) 291-298
In California, the toxic algal species of primary concern are the dinoflagellate Alexandrium catenella and members of the pennate diatom genus Pseudo-nitzschia, both producers of potent neurotoxins that are capable of sickening and killing marine life and humans. During the summer of 2004 in Monterey Bay, we observed a change...
Evaluation of trap capture in a geographically closed population of brown treesnakes on Guam
C.L. Tyrrell, M.T. Christy, G.H. Rodda, A. A. Yackel Adams, A.R. Ellingson, J. A. Savidge, K. Dean-Bradley, R. Bischof
2009, Journal of Applied Ecology (46) 128-135
1. Open population mark-recapture analysis of unbounded populations accommodates some types of closure violations (e.g. emigration, immigration). In contrast, closed population analysis of such populations readily allows estimation of capture heterogeneity and behavioural response, but requires crucial assumptions about closure (e.g. no permanent emigration) that are suspect and rarely tested...
Isotopic and trace element constraints on the petrogenesis of lavas from the Mount Adams volcanic field, Washington
B.R. Jicha, G.L. Hart, C.M. Johnson, Wes Hildreth, B.L. Beard, S.B. Shirey, J.W. Valley
2009, Contributions to Mineralogy and Petrology (157) 189-207
Strontium, Nd, Pb, Hf, Os, and O isotope compositions for 30 Quaternary lava flows from the Mount Adams stratovolcano and its basaltic periphery in the Cascade arc, southern Washington, USA indicate a major component from intraplate mantle sources, a relatively small subduction component, and interaction with young mafic crust at...
Depleted uranium analysis in blood by inductively coupled plasma mass spectrometry
T.I. Todorov, H. Xu, J.W. Ejnik, F.G. Mullick, K. Squibb, M.A. McDiarmid, J.A. Centeno
2009, Journal of Analytical Atomic Spectrometry (24) 189-193
In this study we report depleted uranium (DU) analysis in whole blood samples. Internal exposure to DU causes increased uranium levels as well as change in the uranium isotopic composition in blood specimen. For identification of DU exposure we used the 235U/238U ratio in blood samples, which ranges from 0.00725...
Potential effects of runoff, fluvial sediment, and nutrient discharges on the coral reefs of Puerto Rico
M. C. Larsen, R.M.T. Webb
2009, Journal of Coastal Research (25) 189-208
Coral reefs, the foundation and primary structure of many highly productive and diverse tropical marine ecosystems, have been degraded by human activity in much of the earth's tropical oceans. To contribute to improved understanding of this problem, the potential relation between river sediment and nutrient discharges and degradation of coral...
