The effect of multiple stressors on salt marsh end-of-season biomass
J.M. Visser, C.E. Sasser, B.S. Cade
2006, Estuaries and Coasts (29) 331-342
It is becoming more apparent that commonly used statistical methods (e.g. analysis of variance and regression) are not the best methods for estimating limiting relationships or stressor effects. A major challenge of estimating the effects associated with a measured subset of limiting factors is to account for the effects of...
Aqueous processes at Gusev crater inferred from physical properties of rocks and soils along the Spirit traverse
N.A. Cabrol, J.D. Farmer, E.A. Grin, L. Ritcher, L. Soderblom, R. Li, Kenneth E. Herkenhoff, G. A. Landis, R. E. Arvidson
2006, Journal of Geophysical Research E: Planets (111)
Gusev crater was selected as the landing site for Spirit on the basis of morphological evidence of long-lasting water activity, including possibly fluvial and lacustrine episodes. From the Columbia Memorial Station to the Columbia Hills, Spirit's traverse provides a journey back in time, from relatively recent volcanic plains showing little...
Case study: Mapping tsunami hazards associated with debris flow into a reservoir
J. S. Walder, P. Watts, C. F. Waythomas
2006, Journal of Hydraulic Engineering (132) 1-11
Debris-flow generated impulse waves (tsunamis) pose hazards in lakes, especially those used for hydropower or recreation. We describe a method for assessing tsunami-related hazards for the case in which inundation by coherent water waves, rather than chaotic splashing, is of primary concern. The method involves an experimentally based initial condition...
Terrestrial ice streams-a view from the lobe
C.E. Jennings
2006, Geomorphology (75) 100-124
The glacial landforms of Minnesota are interpreted as the products of the lobate extensions of ice streams that issued from various ice sheds within the Laurentide Ice Sheet. Low-relief till plains, trough-shaped lowlands, boulder pavements, and streamlined forms make up the subglacial landsystem in Minnesota that is interpreted as having...
Sensitivity of two salamander (Ambystoma) species to ultraviolet radiation
R.D. Calfee, C.M. Bridges, E. E. Little
2006, Journal of Herpetology (40) 35-42
Increased ultraviolet-B (UV-B) radiation reaching the Earth's surface has been implicated in amphibian declines. Recent studies have shown that many amphibian species have differences in sensitivity depending on developmental stage. Embryos and larvae of Ambystoma maculatum (Spotted Salamander) and larvae of Ambystoma talpoideum (Mole Salamander) were exposed to five simulated...
Ostracods and facies of the Early and Middle Frasnian at Devils Gate in Nevada: Relationship to the Alamo Event
J.-G. Casier, I. Berra, Ewa Olempska, Charles Sandberg, A. Preat
2006, Acta Palaeontologica Polonica (51) 813-828
In order to document the Alamo Event and to investigate its influence on shallow-marine environments, we undertook a study of ostracods, conodonts, and analysis of the sedimentology of the lower member of the type Devils Gate Limestone, Six major carbonate microfacies (MF1-MF6) ranging from open-marine environments below storm wave base...
The conservation and population status of the world's waders at the turn of the millennium
David A. Stroud, Andy Baker, D.E. Blanco, Nick C. Davidson, B. Ganter, Robert E. Gill Jr., P.M. Gonzalez, L. Haanstra, R. I. G. Morrison, Theunis Piersma, D. Scott, O. Thorup, R. West, J.L. Wilson, Christoph Zockler
Gerard C. Boere, Colin A. Galbraith, David A. Stroud, editor(s)
2006, Conference Paper, Waterbirds around the world: A global overview of the conservation, management, and research of the world's waterbird flyways
Using information from many sources, but especially data collated for the third edition of Wetlands International’s Waterbird Population Estimates, we review the status of the world’s waders in the late 1990s. There are widespread declines in most regions and biotopes caused principally by loss and degradation of wetland (and other)...
Episodic fresh surface waters in the Eocene Arctic Ocean
H. Brinkhuis, S. Schouten, M.E. Collinson, A. Sluijs, J.S.S. Damste, G.R. Dickens, M. Huber, T. M. Cronin, J. Onodera, K. Takahashi, J.P. Bujak, R. Stein, J. Van Der Burgh, J.S. Eldrett, I.C. Harding, A.F. Lotter, F. Sangiorgi, H.V.K.V. Cittert, J. W. De Leeuw, J. Matthiessen, J. Backman, K. Moran
2006, Nature (441) 606-609
It has been suggested, on the basis of modern hydrology and fully coupled palaeoclimate simulations, that the warm greenhouse conditions that characterized the early Palaeogene period (55-45 Myr ago) probably induced an intensified hydrological cycle with precipitation exceeding evaporation at high latitudes. Little field evidence, however, has been available to...
Abundance of adult saugers across the Wind River watershed, Wyoming
C.J. Amadio, W.A. Hubert, Kevin Johnson, D. Oberlie, D. Dufek
2006, North American Journal of Fisheries Management (26) 156-162
The abundance of adult saugers Sander canadensis was estimated over 179 km of continuous lotic habitat across a watershed on the western periphery of their natural distribution in Wyoming. Three-pass depletions with raft-mounted electrofishing gear were conducted in 283 pools and runs among 19 representative reaches totaling 51 km during...
Controls on soil pore water solutes: An approach for distinguishing between biogenic and lithogenic processes
A. F. White, M. S. Schulz, D.V. Vivit, A.E. Blum, David A. Stonestrom
2006, Journal of Geochemical Exploration (88) 363-366
Spatial and temporal variations in pore water compositions are characterized for a deep regolith profile developed on a marine terrace chronosequence near Santa Cruz California. Variations are resolved in terms of the dominance of either a lithogenic process, i.e. chemical weathering, or a biogenic process, i.e. plant nutrient cycling. The concept of elemental fractionation is introduced describing...
Application of Bacteroides fragilis phage as an alternative indicator of sewage pollution in Tampa Bay, Florida
M.R. McLaughlin, J.B. Rose
2006, Estuaries and Coasts (29) 246-256
Traditional fecal coliform bacterial indicators have been found to be severely limited in determining the significance and sources of fecal contamination in ambient waters of tropical and subtropical regions. The bacteriophages that infectBacteroides fragilis have been suggested as better fecal indicators and at least one type may be human specific. In...
Diversity, composition, and geographical distribution of microbial communities in California salt marsh sediments
A. L. Cordova-Kreylos, Y. Cao, P.G. Green, H.-M. Hwang, K.M. Kuivila, M.G. LaMontagne, L. C. Van De Werfhorst, P.A. Holden, K.M. Scow
2006, Applied and Environmental Microbiology (72) 3357-3366
The Pacific Estuarine Ecosystem Indicators Research Consortium seeks to develop bioindicators of toxicant-induced stress and bioavailability for wetland biota. Within this framework, the effects of environmental and pollutant variables on microbial communities were studied at different spatial scales over a 2-year period. Six salt marshes along the California coastline were...
Long-term eruptive activity at a submarine arc volcano
R.W. Embley, W.W. Chadwick Jr., E.T. Baker, D.A. Butterfield, J.A. Resing, Cornel E. J. de Ronde, V. Tunnicliffe, J.E. Lupton, S.K. Juniper, K.H. Rubin, R. J. Stern, G.T. Lebon, K.-I. Nakamura, S.G. Merle, J.R. Hein, D.A. Wiens, Y. Tamura
2006, Nature (441) 494-497
Three-quarters of the Earth's volcanic activity is submarine, located mostly along the mid-ocean ridges, with the remainder along intraoceanic arcs and hotspots at depths varying from greater than 4,000 m to near the sea surface. Most observations and sampling of submarine eruptions have been indirect, made from surface vessels or...
Carbon dioxide emissions from vegetation-kill zones around the resurgent dome of Long Valley caldera, eastern California, USA
Deborah Bergfeld, William C. Evans, James F. Howle, Christopher D. Farrar
2006, Journal of Volcanology and Geothermal Research (152) 140-156
A survey of diffuse CO2 efflux, soil temperature and soil-gas chemistry over areas of localized vegetation-kill on and around the resurgent dome of Long Valley caldera California was performed to evaluate the premise that gaseous and thermal anomalies are related to renewed intrusion of magma....
Scale effects of hydrostratigraphy and recharge zonation on base flow
P. F. Juckem, R. J. Hunt, Marilyn P. Anderson
2006, Ground Water (44) 362-370
Uncertainty regarding spatial variations of model parameters often results in the simplifying assumption that parameters are spatially uniform. However, spatial variability may be important in resource assessment and model calibration. In this paper, a methodology is presented for estimating a critical basin size, above which base flows appear to be...
Geophysical evaluation of the Success Dam foundation, Porterville, California
L. E. Hunter, M.H. Powers, S. Haines, T. Asch, B.L. Burton, D.C. Serafini
2006, Conference Paper, Association of State Dam Safety Officials - Dam Safety 2006, Proceedings from the 2006 Annual Conference
Success Dam is a zonedearth fill embankment located near Porterville, CA. Studies of Success Dam by the recent Dam Safety Assurance Program (DSAP) have demonstrated the potential for seismic instability and large deformation of the dam due to relatively low levels of earthquake shaking. The U.S. Army Corps of Engineers...
Nitrogen loads to estuaries from waste water plumes: Modeling and isotopic approaches
K.D. Kroeger, Marci L. Cole, J.K. York, I. Valiela
2006, Ground Water (44) 188-200
We developed, and applied in two sites, novel methods to measure ground water-borne nitrogen loads to receiving estuaries from plumes resulting from land disposal of waste water treatment plant (WWTP) effluent. In addition, we quantified nitrogen losses from WWTP effluent during transport through watersheds. WWTP load to receiving water was...
Ground-water surface-water interactions and long-term change in riverine riparian vegetation in the southwestern United States
R. H. Webb, S. A. Leake
2006, Conference Paper, Journal of Hydrology
Riverine riparian vegetation has changed throughout the southwestern United States, prompting concern about losses of habitat and biodiversity. Woody riparian vegetation grows in a variety of geomorphic settings ranging from bedrock-lined channels to perennial streams crossing deep alluvium and is dependent on interaction between ground-water and surface-water resources. Historically, few...
Growth history of Kilauea inferred from volatile concentrations in submarine-collected basalts
Michelle L. Coombs, Thomas W. Sisson, Peter W. Lipman
2006, Journal of Volcanology and Geothermal Research (151) 19-49
Major-element and volatile (H2O, CO2, S) compositions of glasses from the submarine flanks of Kilauea Volcano record its growth from pre-shield into tholeiite shield-stage. Pillow lavas of mildly alkalic basalt at 2600–1900 mbsl on the upper slope of the south flank are an intermediate link...
Trends in the nutrient enrichment of U.S. rivers during the late 20th century and their relation to changes in probable stream trophic conditions
R. B. Alexander, R. A. Smith
2006, Conference Paper, Limnology and Oceanography
We estimated trends in concentrations of total phosphorus (TP) and total nitrogen (TN) and the related change in the probabilities of trophic conditions from 1975 to 1994 at 250 nationally representative riverine monitoring locations in the U.S. with drainage areas larger than about 1,000 km2. Statistically significant (p < 0.05)...
CO2 outgassing in a combined fracture and conduit karst aquifer near lititz spring, Pennsylvania
L. Toran, E. Roman
2006, Special Paper of the Geological Society of America 275-282
Lititz Spring in southeastern Pennsylvania and a nearby domestic well were sampled for 9 months. Although both locations are connected to conduits (as evidenced by a tracer test), most of the year they were saturated with respect to calcite, which is more typical of matrix flow. Geochemical modeling (PHREEQC) was...
Degradation of water quality by bird feces in and around managed wetlands
G.G. Shellenbarger, A.B. Boehm
2006, Conference Paper, Proceedings of the South Bay Science Symposium
No abstract available....
Characterization of surface and ground water δ18O seasonal variation and its use for estimating groundwater residence times
Michael M. Reddy, Paul F. Schuster, Carol Kendall, Micaela B. Reddy
2006, Hydrological Processes (20) 1753-1772
18O is an ideal tracer for characterizing hydrological processes because it can be reliably measured in several watershed hydrological compartments. Here, we present multiyear isotopic data, i.e. 18O variations (δ18O), for precipitation inputs, surface water and groundwater in the Shingobee River Headwaters Area (SRHA), a well-instrumented research catchment in north-central Minnesota....
Gas-water-rock interactions in Frio Formation following CO2 injection: Implications for the storage of greenhouse gases in sedimentary basins
Yousif K. Kharaka, David R. Cole, Susan D. Hovorka, W.D. Gunter, Kevin G. Knauss, Barry M. Freifeild
2006, Geology (34) 577-580
To investigate the potential for the geologic storage of CO2 in saline sedimentary aquifers, 1600 t of CO2 were injected at 1500 m depth into a 24-m-thick sandstone section of the Frio Formation, a regional brine and oil reservoir in the U.S. Gulf Coast....
Arsenic, cadmium, lead, and mercury in surface soils, Pueblo, Colorado: Implications for population health risk
D.M. Diawara, J.S. Litt, D. Unis, N. Alfonso, L.A. Martinez, J.G. Crock, D. B. Smith, J. Carsella
2006, Environmental Geochemistry and Health (28) 297-315
Decades of intensive industrial and agricultural practices as well as rapid urbanization have left communities like Pueblo, Colorado facing potential health threats from pollution of its soils, air, water and food supply. To address such concerns about environmental contamination, we conducted an urban geochemical study of the city of Pueblo...
