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Page 190, results 4726 - 4750

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Not all publications have extents, not all extents are completely accurate
Flow regime, temperature, and biotic interactions drive differential declines of trout species under climate change
S.J. Wenger, D.J. Isaak, C.H. Luce, H.M. Neville, K.D. Fausch, J. B. Dunham, D.C. Dauwalter, M.K. Young, M.M. Elsner, B.E. Rieman, A.F. Hamlet, J.E. Williams
2011, Proceedings of the National Academy of Sciences of the United States of America (108) 14175-14180
Broad-scale studies of climate change effects on freshwater species have focused mainly on temperature, ignoring critical drivers such as flow regime and biotic interactions. We use downscaled outputs from general circulation models coupled with a hydrologic model to forecast the effects of altered flows and increased temperatures on four interacting...
The high life: Transport of microbes in the atmosphere
D.J. Smith, Dale W. Griffin, D.A. Jaffe
2011, Eos, Transactions, American Geophysical Union (92) 249-250
Microbes (bacteria, fungi, algae, and viruses) are the most successful types of life on Earth because of their ability to adapt to new environments, reproduce quickly, and disperse globally. Dispersal occurs through a number of vectors, such as migrating animals or the hydrological cycle, but transport by wind may be...
Rangewide phylogeography and landscape genetics of the Western U.S. endemic frog Rana boylii (Ranidae): Implications for the conservation of frogs and rivers
A.J. Lind, P.Q. Spinks, G. M. Fellers, H.B. Shaffer
2011, Conservation Genetics (12) 269-284
Genetic data are increasingly being used in conservation planning for declining species. We sampled both the ecological and distributional limits of the foothill yellow-legged frog, Rana boylii to characterize mitochondrial DNA (mtDNA) variation in this declining, riverine amphibian. We evaluated 1525 base pairs (bp) of cytochrome b and ND2 fragments...
Arsenic in sediments, groundwater, and streamwater of a glauconitic Coastal Plain terrain, New Jersey, USA-Chemical " fingerprints" for geogenic and anthropogenic sources
Julia Barringer, Pamela A. Reilly, D. D. Eberl, A.E. Blum, J.L. Bonin, Robert Rosman, B. Hirst, M. Alebus, K. Cenno, M. Gorska
2011, Applied Geochemistry (26) 763-776
Glauconite-bearing deposits are found worldwide, but As levels have been determined for relatively few. The As content of glauconites in sediments of the Inner Coastal Plain of New Jersey can exceed 100 mg/kg, and total As concentrations (up to 5.95 μg/L) found historically and recently in streamwaters exceed the State standard. In...
Calibration of models using groundwater age
Ward E. Sanford
2011, Hydrogeology Journal (19) 13-16
There have been substantial efforts recently by geochemists to determine the age of groundwater (time since water entered the system) and its uncertainty, and by hydrologists to use these data to help calibrate groundwater models. This essay discusses the calibration of models using groundwater age, with conclusions that emphasize what...
What is the role of fresh groundwater and recirculated seawater in conveying nutrients to the coastal ocean?
Yishai Weinstein, Yoseph Yechieli, Yehuda Shalem, William C. Burnett, Peter W. Swarzenski, Barak Herut
2011, Environmental Science and Technology (45) 5195-5200
Submarine groundwater discharge (SGD) is a major process operating at the land-sea interface. Quantifying the SGD nutrient loads and the marine/terrestrial controls of this transport is of high importance, especially in oligotrophic seas such as the eastern Mediterranean. The fluxes of nutrients in groundwater discharging from the seafloor at Dor...
Lake carbonate-δ18 records from the Yukon Territory, Canada: Little Ice Age moisture variability and patterns
Lesleigh Anderson, Bruce P. Finney, Mark D. Shapley
2011, Quaternary Science Reviews (30) 887-898
A 1000-yr history of climate change in the central Yukon Territory, Canada, is inferred from sediment composition and isotope geochemistry from small, groundwater fed, Seven Mile Lake. Recent observations of lake-water δ18O, lake level, river discharge, and climate variations, suggest that changes in regional effective moisture (precipitation minus evaporation) are...
Removal of inorganic mercury and methylmercury from surface waters following coagulation of dissolved organic matter with metal-based salts
Y.K. Henneberry, T.E.C. Kraus, J.A. Fleck, David P. Krabbenhoft, P.M. Bachand, W.R. Horwath
2011, Science of the Total Environment (409) 631-637
The presence of inorganic mercury (IHg) and methylmercury (MeHg) in surface waters is a health concern worldwide. This study assessed the removal potential use of metal-based coagulants as a means to remove both dissolved IHg and MeHg from natural waters and provides information regarding the importance of Hg associations with...
Coordinating standards and applications for optical water quality sensor networks
B. Bergamaschi, B. Pellerin
2011, Conference Paper, Eos
Joint USGS-CUAHSI Workshop: In Situ Optical Water Quality Sensor Networks; Shepherdstown, West Virginia, 8-10 June 2011; Advanced in situ optical water quality sensors and new techniques for data analysis hold enormous promise for advancing scientific understanding of aquatic systems through measurements of important biogeochemical parameters at the time scales over...
Sources and Delivery of Nutrients to the Northwestern Gulf of Mexico from Streams in the South-Central United States
Richard A. Rebich, Natalie A. Houston, Scott V. Mize, Daniel Pearson, Patricia B. Ging, Hornig C. Evan
2011, Journal of the American Water Resources Association (47) 1061-1086
SPAtially Referenced Regressions On Watershed attributes (SPARROW) models were developed to estimate nutrient inputs [total nitrogen (TN) and total phosphorus (TP)] to the northwestern part of the Gulf of Mexico from streams in the South‐Central United States (U.S.). This area included drainages of the Lower Mississippi, Arkansas‐White‐Red, and Texas‐Gulf hydrologic...
Modeling of hydroecological feedbacks predicts distinct classes of landscape pattern, process, and restoration potential in shallow aquatic ecosystems
Laurel G. Larsen, Judson W. Harvey
2011, Geomorphology (126) 279-296
It is widely recognized that interactions between vegetation and flow cause the emergence of channel patterns that are distinct from the standard Schumm classification of river channels. Although landscape pattern is known to be linked to ecosystem services such as habitat provision, pollutant removal, and sustaining biodiversity, the mechanisms...
Metallothionein-like multinuclear clusters of mercury(II) and sulfur in peat
K. L. Nagy, A. Manceau, J. D. Gasper, J. N. Ryan, G. R. Aiken
2011, Environmental Science & Technology (45) 7298-7306
Strong mercury(II)–sulfur (Hg-SR) bonds in natural organic matter, which influence mercury bioavailability, are difficult to characterize. We report evidence for two new Hg-SR structures using X-ray absorption spectroscopy in peats from the Florida Everglades with added Hg. The first, observed at...
Comparison of bottom-track to global positioning system referenced discharges measured using an acoustic Doppler current profiler
Chad R. Wagner, David S. Mueller
2011, Journal of Hydrology (401) 250-258
A negative bias in discharge measurements made with an acoustic Doppler current profiler (ADCP) can be caused by the movement of sediment on or near the streambed. The integration of a global positioning system (GPS) to track the movement of the ADCP can be used to avoid the systematic negative...
A distribution-based parameterization for improved tomographic imaging of solute plumes
Adam Pidlisecky, K. Singha, F. D. Day-Lewis
2011, Geophysical Journal International (187) 214-224
Difference geophysical tomography (e.g. radar, resistivity and seismic) is used increasingly for imaging fluid flow and mass transport associated with natural and engineered hydrologic phenomena, including tracer experiments, in situ remediation and aquifer storage and recovery. Tomographic data are collected over time, inverted and differenced against a background image to produce ‘snapshots’...
Effects of sediment-associated extractable metals, degree of sediment grain sorting, and dissolved organic carbon upon Cryptosporidium parvum removal and transport within riverbank filtration sediments, Sonoma County, California
D.W. Metge, R.W. Harvey, G. R. Aiken, R. Anders, G. Lincoln, James Jasperse, M. C. Hill
2011, Environmental Science & Technology (45) 5587-5595
Oocysts of the protozoan pathogen Cryptosporidium parvum are of particular concern for riverbank filtration (RBF) operations because of their persistence, ubiquity, and resistance to chlorine disinfection. At the Russian River RBF site (Sonoma County, CA), transport of C. parvumoocysts and oocyst-sized (3 μm) carboxylate-modified microspheres through poorly sorted (sorting indices, σ1, up to...
Quantifying the hydrological responses to climate change in an intact forested small watershed in Southern China
G. Zhou, X. Wei, Y. Wu, Y. Huang, J. Yan, Dongxiao Zhang, Q. Zhang, J. Liu, Z. Meng, C. Wang, G. Chu, S. Liu, X. Tang, Xiuying Liu
2011, Global Change Biology (17) 3736-3746
Responses of hydrological processes to climate change are key components in the Intergovernmental Panel for Climate Change (IPCC) assessment. Understanding these responses is critical for developing appropriate mitigation and adaptation strategies for sustainable water resources management and protection of public safety. However, these responses are not well understood and little...
Assessing field-scale biogeophysical signatures of bioremediation over a mature crude oil spill
Lee Slater, Dimitrios Ntarlagiannis, Estella Atekwana, Farag Mewafy, Andre Revil, Magnus Skold, Yuri Gorby, Frederick D. Day-Lewis, John W. Lane Jr., Dale D. Werkema, Jared J. Trost, Geoffrey N. Delin, William N. Herkelrath
H.V. Rectanus, R. Sirabian, editor(s)
2011, Conference Paper, Proceedings of the first international symposium on bioremediation and sustainable environmental technologies
We conducted electrical geophysical measurements at the National Crude Oil Spill Fate and Natural Attenuation Research Site (Bemidji, MN). Borehole and surface self-potential measurements do not show evidence for the existence of a biogeobattery mechanism in response to the redox gradient resulting from biodegradation of oil. The relatively small self...
Seasonal variations in ectotherm growth rates: Quantifying growth as an intermittent non steady state compensatory process
J. -M. Guarini, Laurent Chauvaud, James E. Cloern, J. Clavier, J. Coston-Guarini, Y. Patry
2011, Journal of Sea Research (65) 355-361
Generally, growth rates of living organisms are considered to be at steady state, varying only under environmental forcing factors. For example, these rates may be described as a function of light for plants or organic food resources for animals and these could be regulated (or not) by temperature or other...
Effects of model layer simplification using composite hydraulic properties
Eve L. Kuniansky, Nicasio Sepulveda
Lakshmanan Elango, editor(s)
2011, Book chapter, Hydraulic conductivity: Issues, determination and applications
Groundwater provides much of the fresh drinking water to more than 1.5 billion people in the world (Clarke et al., 1996) and in the United States more that 50 percent of citizens rely on groundwater for drinking water (Solley et al., 1998). As aquifer systems are developed for water supply,...
Re-establishing marshes can return carbon sink functions to a current carbon source in the Sacramento-San Joaquin Delta of California, USA
Robin L. Miller, Roger Fujii
Paul E. Schmidt, editor(s)
2011, Book chapter, River deltas: Types, structures and ecology
The Sacramento-San Joaquin Delta in California was an historic, vast inland freshwater wetland, where organic soils almost 20 meters deep formed over the last several millennia as the land surface elevation of marshes kept pace with sea level rise. A system of levees and pumps were installed in the late...
Alteration of streamflow magnitudes and potential ecological consequences: A multiregional assessment
Daren M. Carlisle, David M. Wolock, Michael R. Meador
2011, Frontiers in Ecology and the Environment (9) 264-270
Human impacts on watershed hydrology are widespread in the US, but the prevalence and severity of stream‐flow alteration and its potential ecological consequences have not been quantified on a national scale. We assessed streamflow alteration at 2888 streamflow monitoring sites throughout the conterminous US. The magnitudes of mean annual (1980–2007)...
Alteration of streamflow magnitudes and potential ecological consequences: A multiregional assessment
Daren M. Carlisle, David M. Wolock, Michael R. Meador
2011, Frontiers in Ecology and the Environment (9) 264-270
Human impacts on watershed hydrology are widespread in the US, but the prevalence and severity of stream-flow alteration and its potential ecological consequences have not been quantified on a national scale. We assessed streamflow alteration at 2888 streamflow monitoring sites throughout the conterminous US. The magnitudes of mean annual (1980–2007)...
Influence of dissolved organic matter on the environmental fate of metals, nanoparticles, and colloids
George R. Aiken, Heileen Hsu-Kim, Joseph N. Ryan
2011, Environmental Science & Technology (45) 3196-3201
We have known for decades that dissolved organic matter (DOM) plays a critical role in the biogeochemical cycling of trace metals and the mobility of colloidal particles in aquatic environments. In recent years, concerns about the ecological and human health effects of metal-based engineered nanoparticles released into natural waters have...
Watershed-scale response to climate change through the twenty-first century for selected basins across the United States
Lauren E. Hay, Steven L. Markstrom, Christian D. Ward-Garrison
2011, Earth Interactions (15) 1-37
The hydrologic response of different climate-change emission scenarios for the twenty-first century were evaluated in 14 basins from different hydroclimatic regions across the United States using the Precipitation-Runoff Modeling System (PRMS), a process-based, distributed-parameter watershed model. This study involves four major steps: 1) setup and calibration of the PRMS model...
In situ rates of sulfate reduction in response to geochemical perturbations
T.A. Kneeshaw, J.T. McGuire, Isabelle M. Cozzarelli, E.W. Smith
2011, Ground Water (49) 903-913
Rates of in situ microbial sulfate reduction in response to geochemical perturbations were determined using Native Organism Geochemical Experimentation Enclosures (NOGEEs), a new in situ technique developed to facilitate evaluation of controls on microbial reaction rates. NOGEEs function by first trapping a native microbial community in situ and then subjecting...