Using packrat middens to assess grazing effects on vegetation change
J. Fisher, K.L. Cole, R. Scott Anderson
2009, Journal of Arid Environments (73) 937-948
Research on grazing effects usually compares the same sites through time or grazed and ungrazed sites over the same time period. Both approaches are complicated in arid environments where grazing can have a long undocumented history and landscapes can be spatially heterogenous. This work employs both approaches simultaneously by comparing...
Development of a liquefaction hazard screening tool for caltrans bridge sites
Kathy L. Knudsen, J.D.J. Bott, M.O. Woods, T.L. McGuire
2009, Conference Paper, TCLEE 2009: Lifeline Earthquake Engineering in a Multihazard Environment
We have developed a liquefaction hazard screening tool for the California Department of Transportation (Caltrans) that is being used to evaluate the liquefaction hazard to approximately 13,000 bridge sites in California. Because of the large number of bridge sites to be evaluated, we developed a tool that makes use of...
Antipredator responses by native mosquitofish to non-native cichlids: An examination of the role of prey naiveté
Jennifer S. Rehage, Katherine L. Dunlop, William F. Loftus
2009, Ethology (115) 1046-1056
The strong impact of non-native predators in aquatic systems is thought to relate to the evolutionary naiveté of prey. Due to isolation and limited dispersal, this naiveté may be relatively high in freshwater systems. In this study, we tested this notion by examining the antipredator response of native mosquitofish, Gambusia holbrooki, to...
Nutrient availability and phytoplankton nutrient limitation across a gradient of atmospheric nitrogen deposition
J.J. Elser, M. Kyle, L. Steuer, K. R. Nydick, Jill Baron
2009, Ecology (90) 3062-3073
Atmospheric nitrogen (N) deposition to lakes and watersheds has been increasing steadily due to various anthropogenic activities. Because such anthropogenic N is widely distributed, even lakes relatively removed from direct human disturbance are potentially impacted. However, the effects of increased atmospheric N deposition on lakes are not well documented, We...
Feldspar dissolution rates in the Topopah Spring Tuff, Yucca Mountain, Nevada
C.R. Bryan, K.B. Helean, B.D. Marshall, P.V. Brady
2009, Applied Geochemistry (24) 2133-2143
Two different field-based methods are used here to calculate feldspar dissolution rates in the Topopah Spring Tuff, the host rock for the proposed nuclear waste repository at Yucca Mountain, Nevada. The center of the tuff is a high silica rhyolite, consisting...
Physical modeling of river spanning rock structures: Evaluating interstitial flow, local hydraulics, downstream scour development, and structure stability
K.L. Collins, C.I. Thornton, B. Mefford, C. L. Holmquist-Johnson
2009, Conference Paper, Proceedings of World Environmental and Water Resources Congress 2009 - World Environmental and Water Resources Congress 2009: Great Rivers
Rock weir and ramp structures uniquely serve a necessary role in river management: to meet water deliveries in an ecologically sound manner. Uses include functioning as low head diversion dams, permitting fish passage, creating habitat diversity, and stabilizing stream banks and profiles. Existing information on design and performance of in-stream...
A historical perspective on the "fish tumors or other deformities" beneficial use impairment at Great Lakes Areas of Concern
S.D. Rafferty, V. S. Blazer, A.E. Pinkney, J.L. Grazio, E.C. Obert, L. Boughton
2009, Journal of Great Lakes Research (35) 496-506
The Great Lakes Water Quality Agreement defines Areas of Concern as geographic areas that fail to meet the general or specific objectives of the agreement where such failure has caused or is likely to cause impairment of beneficial use of the area's ability to support aquatic life. One of the...
Integrating GIS-based geologic mapping, LiDAR-based lineament analysis and site specific rock slope data to delineate a zone of existing and potential rock slope instability located along the grandfather mountain window-Linville Falls shear zone contact, Southern Appalachian Mountains, Watauga County, North Carolina
K.A. Gillon, R.M. Wooten, R.L. Latham, A.W. Witt, T.J. Douglas, J.B. Bauer, S.J. Fuemmeler
2009, Conference Paper, 43rd U.S. Rock Mechanics Symposium and 4th U.S.-Canada Rock Mechanics Symposium
Landslide hazard maps of Watauga County identify >2200 landslides, model debris flow susceptibility, and evaluate a 14km x 0.5km zone of existing and potential rock slope instability (ZEPRSI) near the Town of Boone. The ZEPRSI encompasses west-northwest trending (WNWT) topographic ridges where 14 active/past-active rock/weathered rock slides occur mainly in...
A search in strainmeter data for slow slip associated with triggered and ambient tremor near Parkfield, California
E.F. Smith, J. Gomberg
2009, Journal of Geophysical Research B: Solid Earth (114)
We test the hypothesis that, as in subduction zones, slow slip facilitates triggered and ambient tremor in the transform boundary setting of California. Our study builds on the study of Peng et al. (2009) of triggered and ambient tremor near Parkfield, California during time intervals surrounding 31, potentially triggering, M...
The effect of mayfly (Hexagenia spp.) burrowing activity on sediment oxygen demand in western Lake Erie
William J. Edwards, Frederick M. Soster, Gerald Matisoff, Donald W. Schloesser
2009, Journal of Great Lakes Research (35) 507-516
Previous studies support the hypothesis that large numbers of infaunal burrow-irrigating organisms in the western basin of Lake Erie may increase significantly the sediment oxygen demand, thus enhancing the rate of hypolimnetic oxygen depletion. We conducted laboratory experiments to quantify burrow oxygen dynamics and increased oxygen demand resulting from burrow...
Evaluation of two spike-and-recovery controls for assessment of extraction efficiency in microbial source tracking studies
D. M. Stoeckel, E.A. Stelzer, L.K. Dick
2009, Water Research (43) 4820-4827
Quantitative PCR (qPCR), applied to complex environmental samples such as water, wastewater, and feces, is susceptible to methodological and sample related biases. In this study, we evaluated two exogenous DNA spike-and-recovery controls as proxies for recovery efficiency of Bacteroidales 16S rDNA gene sequences (AllBac and qHF183) that are used for...
Effects of sediment transport and seepage direction on hydraulic properties at the sediment-water interface of hyporheic settings
D.O. Rosenberry, J. Pitlick
2009, Journal of Hydrology (373) 377-391
Relations between seepage flux and hydraulic properties are difficult to quantify in fluvial settings because of the difficulty in measuring these variables in situ. Tests conducted in a 1.5-m diameter by 1.5-m tall sediment-filled tank indicate that hydraulic gradient increased and hydraulic conductivity (K) decreased following the onset of downward...
Phenotypic plasticity in age at first reproduction of female northern sea otters (Enhydra lutris kenyoni)
Vanessa R. von Biela, V.A. Gill, James L. Bodkin, Jennifer M. Burns
2009, Journal of Mammalogy (90) 1224-1231
Life-history theory predicts that within a species, reproduction and survival rates will differ among populations that differ in resource availability or predation rates through phenotypic plasticity. When populations are near carrying capacity (K) or when they are declining due to reduced prey resources, the average age at 1st reproduction (average...
Global irrigated area map (GIAM), derived from remote sensing, for the end of the last millennium
P.S. Thenkabail, C.M. Biradar, P. Noojipady, V. Dheeravath, Y. Li, M. Velpuri, M. Gumma, O.R.P. Gangalakunta, H. Turral, X. Cai, J. Vithanage, M.A. Schull, R. Dutta
2009, International Journal of Remote Sensing (30) 3679-3733
A Global Irrigated Area Map (GIAM) has been produced for the end of the last millennium using multiple satellite sensor, secondary, Google Earth and groundtruth data. The data included: (a) Advanced Very High Resolution Radiometer (AVHRR) 3-band and Normalized Difference Vegetation Index (NDVI) 10 km monthly time-series for 1997-1999, (b)...
Using LiDAR and quickbird data to model plant production and quantify uncertainties associated with wetland detection and land cover generalizations
B.D. Cook, P.V. Bolstad, E. Naesset, R. Scott Anderson, S. Garrigues, J.T. Morisette, J. Nickeson, K.J. Davis
2009, Remote Sensing of Environment (113) 2366-2379
Spatiotemporal data from satellite remote sensing and surface meteorology networks have made it possible to continuously monitor global plant production, and to identify global trends associated with land cover/use and climate change. Gross primary production (GPP) and net primary production (NPP) are routinely derived from the Moderate Resolution Imaging Spectroradiometer...
Changes in West Nile virus seroprevalence and antibody titers among Wisconsin mesopredators 2003-2006
Douglas E. Docherty, Michael D. Samuel, Kristina F. Egstad, Kathryn M. Griffin, Cherrie A. Nolden, L. Karwal, S. Ip
2009, American Journal of Tropical Medicine and Hygiene (81) 177-179
After the 2001 occurrence of West Nile virus (WNV) in Wisconsin (WI), we collected sera, during 2003–2006, from south-central WI mesopredators. We tested these sera to determine WNV antibody prevalence and geometric mean antibody titer (GMAT). Four-fold higher antibody prevalence and 2-fold higher GMAT in 2003–2004 indicated greater exposure of...
Water uptake and nutrient concentrations under a floodplain oak savanna during a non-flood period, lower Cedar River, Iowa
K. E. Schilling, P. Jacobson
2009, Hydrological Processes (23) 3006-3016
Floodplains during non-flood periods are less well documented than when flooding occurs, but non-flood periods offer opportunities to investigate vegetation controls on water and nutrient cycling. In this study, we characterized water uptake and nutrient concentration patterns from 2005 to 2007 under an oak savanna located on the floodplain of...
Rapid changes in small fish mercury concentrations in estuarine wetlands: Implications for wildlife risk and monitoring programs
Collin A. Eagles-Smith, Joshua T. Ackerman
2009, Environmental Science & Technology (43) 8658-8664
Small fish are commonly used to assess mercury (Hg) risk to wildlife and monitor Hg in wetlands. However, limited research has evaluated short-term Hg variability in small fish, which can have important implications for monitoring programs and risk assessment. We conducted a time-series study of Hg concentrations in two small...
Lysimetric evaluation of simplified surface energy balance approach in the Texas high plains
P.H. Gowda, G.B. Senay, T.A. Howell, T.H. Marek
2009, Applied Engineering in Agriculture (25) 665-669
Numerous energy balance (EB) algorithms have been developed to make use of remote sensing data to estimate evapotranspiration (ET) regionally. However, most EB models are complex to use and efforts are being made to simplify procedures mainly through the scaling of reference ET. The Simplified Surface Energy Balance (SSEB) is...
Fluvial fluxes of water, suspended particulate matter, and nutrients and potential impacts on tropical coastal water Biogeochemistry: Oahu, Hawai'i
D.J. Hoover, F.T. MacKenzie
2009, Aquatic Geochemistry (15) 547-570
Baseflow and storm runoff fluxes of water, suspended particulate matter (SPM), and nutrients (N and P) were assessed in conservation, urban, and agricultural streams discharging to coastal waters around the tropical island of Oahu, Hawai'i. Despite unusually low storm frequency and intensity during the study, storms accounted for 8-77% (median...
Historical and simulated ecosystem carbon dynamics in Ghana: Land use, management, and climate
Z. Tan, L.L. Tieszen, E. Tachie-Obeng, S. Liu, A.M. Dieye
2009, Biogeosciences (6) 45-58
We used the General Ensemble biogeochemical Modeling System (GEMS) to simulate responses of natural and managed ecosystems to changes in land use and land cover, management, and climate for a forest/savanna transitional zone in central Ghana. Model results show that deforestation for crop production during the 20th century resulted in...
Tsunamis and splay fault dynamics
J. Wendt, D. D. Oglesby, E.L. Geist
2009, Geophysical Research Letters (36)
The geometry of a fault system can have significant effects on tsunami generation, but most tsunami models to date have not investigated the dynamic processes that determine which path rupture will take in a complex fault system. To gain insight into this problem, we use the 3D finite element method...
SSTL UK-DMC SLIM-6 data quality assessment
G. Chander, S. Saunier, M.J. Choate, P. L. Scaramuzza
2009, IEEE Transactions on Geoscience and Remote Sensing (47) 2380-2391
Satellite data from the Surrey Satellite Technology Limited (SSTL) United Kingdom (UK) Disaster Monitoring Constellation (DMC) were assessed for geometric and radiometric quality. The UK-DMC Surrey Linear Imager 6 (SLIM-6) sensor has a 32-m spatial resolution and a ground swath width of 640 km. The UK-DMC SLIM-6 design consists of...
Can kittiwakes smell? Experimental evidence in a larid species
S. Leclaire, Herve Mulard, R.H. Wagner, Scott A. Hatch, E. Danchin
2009, Ibis (151) 584-587
Birds have long been thought to have a poor sense of smell, although they have the proper anatomical and neurological structures for detecting olfactory cues (Roper 1999). However, in the past decade several bird species have been shown to use smell in various contexts, such as foraging (Nevitt et al. 1995), navigation (Wallraff...
Design of smart sensing components for volcano monitoring
M. Xu, W.-Z. Song, R. Huang, Y. Peng, B. Shirazi, R. LaHusen, A. Kiely, N. Peterson, A. Ma, L. Anusuya-Rangappa, M. Miceli, D. McBride
2009, Pervasive and Mobile Computing (5) 639-653
In a volcano monitoring application, various geophysical and geochemical sensors generate continuous high-fidelity data, and there is a compelling need for real-time raw data for volcano eruption prediction research. It requires the network to support network synchronized sampling, online configurable sensing and situation awareness, which pose significant challenges on sensing...
