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Page 646, results 16126 - 16150

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Not all publications have extents, not all extents are completely accurate
Field experiment provides ground truth for surface nuclear magnetic resonance measurement
R. Knight, E. Grunewald, T. Irons, K. Dlubac, Y. Song, H.N. Bachman, B. Grau, D. Walsh, J.D. Abraham, J. Cannia
2012, Geophysical Research Letters (39) 1-7
The need for sustainable management of fresh water resources is one of the great challenges of the 21st century. Since most of the planet's liquid fresh water exists as groundwater, it is essential to develop non-invasive geophysical techniques to characterize groundwater aquifers. A field experiment was conducted in the High...
Application of a weighted-averaging method for determining paleosalinity: a tool for restoration of south Florida's estuaries
G.L. Wingard, J.W. Hudley
2012, Estuaries and Coasts (35) 262-280
A molluscan analogue dataset is presented in conjunction with a weighted-averaging technique as a tool for estimating past salinity patterns in south Florida’s estuaries and developing targets for restoration based on these reconstructions. The method, here referred to as cumulative weighted percent (CWP), was tested using modern surficial samples collected...
Using multitemporal remote sensing imagery and inundation measures to improve land change estimates in coastal wetlands
Y.C. Allen, B.R. Couvillion, J.A. Barras
2012, Estuaries and Coasts (35) 190-200
Remote sensing imagery can be an invaluable resource to quantify land change in coastal wetlands. Obtaining an accurate measure of land change can, however, be complicated by differences in fluvial and tidal inundation experienced when the imagery is captured. This study classified Landsat imagery from two wetland areas in coastal...
Geostatistical modeling of the gas emission zone and its in-place gas content for Pittsburgh-seam mines using sequential Gaussian simulation
Cevat O. Karacan, Ricardo A. Olea, G. Goodman
2012, International Journal of Coal Geology (90-91) 50-71
Determination of the size of the gas emission zone, the locations of gas sources within, and especially the amount of gas retained in those zones is one of the most important steps for designing a successful methane control strategy and an efficient ventilation system in...
Landscape controls on the timing of spring, autumn, and growing season length in mid-Atlantic forests
A.J. Elmore, S.M. Guinn, B. J. Minsley, A.D. Richardson
2012, Global Change Biology (18) 656-674
The timing of spring leaf development, trajectories of summer leaf area, and the timing of autumn senescence have profound impacts to the water, carbon, and energy balance of ecosystems, and are likely influenced by global climate change. Limited field-based and remote-sensing observations have suggested complex spatial patterns related to geographic...
The impact of biotic/abiotic interfaces in mineral nutrient cycling: A study of soils of the Santa Cruz chronosequence, California
A. F. White, M. S. Schulz, D.V. Vivit, T.D. Bullen, J. Fitzpatrick
2012, Geochimica et Cosmochimica Acta (77) 62-85
Biotic/abiotic interactions between soil mineral nutrients and annual grassland vegetation are characterized for five soils in a marine terrace chronosequence near Santa Cruz, California. A Mediterranean climate, with wet winters and dry summers, controls the annual cycle of plant growth and litter decomposition, resulting in net above-ground productivities of...
Interlaboratory comparison of real-time pcr protocols for quantification of general fecal indicator bacteria
O.C. Shanks, M. Sivaganesan, L. Peed, C.A. Kelty, A.D. Blackwood, M.R. Greene, R.T. Noble, Rebecca N. Bushon, Erin A. Stelzer, J. Kinzelman, T. Anan'Eva, C. Sinigalliano, D. Wanless, J. Griffith, Y. Cao, S. Weisberg, V.J. Harwood, C. Staley, K.H. Oshima, M. Varma, R.A. Haugland
2012, Environmental Science & Technology (46) 945-953
The application of quantitative real-time PCR (qPCR) technologies for the rapid identification of fecal bacteria in environmental waters is being considered for use as a national water quality metric in the United States. The transition from research tool to a standardized protocol requires information on the reproducibility and sources of...
Verifiable metamodels for nitrate losses to drains and groundwater in the Corn Belt, USA
Bernard T. Nolan, Robert W. Malone, Jo Ann M. Gronberg, K.R. Thorp, Liwang Ma
2012, Environmental Science & Technology (46) 901-908
Nitrate leaching in the unsaturated zone poses a risk to groundwater, whereas nitrate in tile drainage is conveyed directly to streams. We developed metamodels (MMs) consisting of artificial neural networks to simplify and upscale mechanistic fate and transport models for prediction of nitrate losses by drains and leaching in the...
Climatic forcing of Quaternary deep-sea benthic communities in the North Pacific Ocean
Moriaki Yasuhara, G. Hunt, T. M. Cronin, N. Hokanishi, H. Kawahata, Akira Tsujimoto, M. Ishitake
2012, Paleobiology (38) 162-179
There is growing evidence that changes in deep-sea benthic ecosystems are modulated by climate changes, but most evidence to date comes from the North Atlantic Ocean. Here we analyze new ostracod and published foraminiferal records for the last 250,000 years on Shatsky Rise in the North Pacific Ocean. Using linear...
An approach to regional wetland digital elevation model development using a differential global positioning system and a custom-built helicopter-based surveying system
J. W. Jones, G.B. Desmond, C. Henkle, R. Glover
2012, International Journal of Remote Sensing (33) 450-465
Accurate topographic data are critical to restoration science and planning for the Everglades region of South Florida, USA. They are needed to monitor and simulate water level, water depth and hydroperiod and are used in scientific research on hydrologic and biologic processes. Because large wetland environments and data acquisition challenge...
Incidence of adult brain cancers is higher in countries where the protozoan parasite Toxoplasma gondii is common
Frederic Thomas, Kevin D. Lafferty, Jacques Brodeur, Eric Elguero, Michel Gauthier-Clerc, Dorothee Misse
2012, Biology Letters (8) 101-103
We explored associations between the common protozoan parasite Toxoplasma gondii and brain cancers in human populations. We predicted that T. gondii could increase the risk of brain cancer because it is a long-lived parasite that encysts in the brain, where it provokes inflammation and inhibits apoptosis. We used a medical...
Occurrence and geochemistry of radium in water from principal drinking-water aquifer systems of the United States
Z. Szabo, Vincent T. DePaul, J.M. Fischer, T. F. Kraemer, E. Jacobsen
2012, Applied Geochemistry (27) 729-752
A total of 1270 raw-water samples (before treatment) were collected from 15 principal and other major aquifer systems (PAs) used for drinking water in 45 states in all major physiographic provinces of the USA and analyzed for concentrations of the Ra isotopes 224Ra, 226Ra and 228Ra establishing...
Geochemical constraints on adakites of different origins and copper mineralization
W.-D. Sun, M.-X. Ling, S.-L. Chung, X. Ding, X.-Y. Yang, H.-Y. Liang, W.-M. Fan, R. Goldfarb, Q.-Z. Yin
2012, Journal of Geology (120) 105-120
The petrogenesis of adakites holds important clues to the formation of the continental crust and copper ± gold porphyry mineralization. However, it remains highly debated as to whether adakites form by slab melting, by partial melting of the lower continental crust, or by fractional crystallization of normal arc magmas. Here,...
A multi-source satellite data approach for modelling Lake Turkana water level: Calibration and validation using satellite altimetry data
N.M. Velpuri, Gabriel B. Senay, K.O. Asante
2012, Hydrology and Earth System Sciences (16) 1-18
Lake Turkana is one of the largest desert lakes in the world and is characterized by high degrees of inter- and intra-annual fluctuations. The hydrology and water balance of this lake have not been well understood due to its remote location and unavailability of reliable ground truth datasets. Managing surface...
Ecological controls on the shell geochemistry of pink and white Globigerinoides ruber in the northern Gulf of Mexico: implications for paleoceanographic reconstruction
Julie N. Richey, Richard Z. Poore, Benjamin P. Flower, David J. Hollander
2012, Marine Micropaleontology (82-83) 28-37
We evaluate the relationship between foraminiferal test size and shell geochemistry (δ13C, δ18O, and Mg/Ca) for two of the most commonly used planktonic foraminifers for paleoceanographic reconstruction in the subtropical Atlantic Ocean: the pink and white varieties of Globigerinoides ruber. Geochemical analyses were performed on foraminifera from modern core-top samples...
Intelligent estimation of spatially distributed soil physical properties
F. Iwashita, Michael J. Friedel, G.F. Ribeiro, Stephen J. Fraser
2012, Geoderma (170) 1-10
Spatial analysis of soil samples is often times not possible when measurements are limited in number or clustered. To obviate potential problems, we propose a new approach based on the self-organizing map (SOM) technique. This approach exploits underlying nonlinear relation of the steady-state geomorphic concave–convex nature of hillslopes (from hilltop...
Semiochemical compounds of preen secretion reflect genetic make-up in a seabird species
S. Leclaire, T. Merkling, C. Raynaud, Herve Mulard, J.-M. Bessiere, E.M. Lhuillier, Scott A. Hatch, E. Danchin
2012, Proceedings of the Royal Society B: Biological Sciences (279) 1185-1193
Several vertebrates choose their mate according to genetic heterozygosity and relatedness, and use odour cues to assess their conspecifics' genetic make-up. In birds, although several species (including the black-legged kittiwake) exhibit non-random mating according to genetic traits, the cues used to assess genetic characteristics remain unknown. The importance of olfaction...
A riverscape perspective of Pacific salmonids and aquatic habitats prior to large-scale dam removal in the Elwha River, Washington, USA
S.J. Brenkman, J.J. Duda, C.E. Torgersen, E. Welty, G.R. Pess, R. Peters, M.L. McHenry
2012, Fisheries Management and Ecology (19) 36-53
 Dam removal has been increasingly proposed as a river restoration technique. In 2011, two large hydroelectric dams will be removed from Washington State’s Elwha River. Ten anadromous fish populations are expected to recolonise historical habitats after dam removal. A key to understanding watershed recolonisation is the collection of spatially continuous...
Nonlinear effects of group size on the success of wolves hunting elk
D.R. MacNulty, D.W. Smith, L. David Mech, J.A. Vucetich, C. Packer
2012, Behavioral Ecology (23) 75-82
Despite the popular view that social predators live in groups because group hunting facilitates prey capture, the apparent tendency for hunting success to peak at small group sizes suggests that the formation of large groups is unrelated to prey capture. Few empirical studies, however, have tested for nonlinear relationships between...
The impact of biotic/abiotic interfaces in mineral nutrient cycling: A study of soils of the Santa Cruz chronosequence, California
Art F. White, Marjorie S. Schulz, Davison V. Vivit, Tomas D. Bullen, John A. Fitzpatrick
2012, Geochimica et Cosmochimica Acta (77) 62-85
Biotic/abiotic interactions between soil mineral nutrients and annual grassland vegetation are characterized for five soils in a marine terrace chronosequence near Santa Cruz, California. A Mediterranean climate, with wet winters and dry summers, controls the annual cycle of plant growth and litter decomposition, resulting in net above-ground productivities of...
Temporal trends in algae, benthic invertebrate, and fish assemblages in streams and rivers draining basins of varying land use in the south-central United States, 1993-2007
Matthew P. Miller, Jonathan G. Kennen, Jeffrey A. Mabe, Scott V. Mize
2012, Hydrobiologia (684) 15-33
Site-specific temporal trends in algae, benthic invertebrate, and fish assemblages were investigated in 15 streams and rivers draining basins of varying land use in the south-central United States from 1993–2007. A multivariate approach was used to identify sites with statistically significant trends in aquatic assemblages which were then tested for...
Geochemical modeling of changes in shallow groundwater chemistry observed during the MSU-ZERT CO2 injection experiment
Liange Zheng, J. A. Apps, N. Spycher, J. Birkholzer, Yousif K. Kharaka, James J. Thordsen, Sarah R. Beers, William N. Herkelrath, Evangelos Kakouros, Robert C. Trautz
2012, International Journal of Greenhouse Gas Control (7) 202-217
A field experiment involving the release of carbon dioxide (CO2) into a shallow aquifer was conducted near Bozeman, Montana, during the summer of 2008, to investigate the potential groundwater quality impacts in the case of leakage of CO2 from deep geological storage. As an essential part...
Fitting a structured juvenile-adult model for green tree frogs to population estimates from capture-mark-recapture field data
Azmy S. Ackleh, J. Carter, Keng Deng, Qihua Huang, Nabendu Pal, Xing Yang
2012, Bulletin of Mathematical Biology (74) 641-665
We derive point and interval estimates for an urban population of green tree frogs (Hyla cinerea) from capture–mark–recapture field data obtained during the years 2006–2009. We present an infinite-dimensional least-squares approach which compares a mathematical population model to the statistical population estimates obtained from the field data. The model is...
Development and use of a floristic quality index for coastal Louisiana marshes
M Jenneke Visser Jenneke, Kari Cretini, Ken W. Krauss, Gregory D. Steyer
2012, Environmental Monitoring and Assessment (184) 2389-2403
The Floristic Quality Index (FQI) has been used as a tool for assessing the integrity of plant communities and for assessing restoration projects in many regions of the USA. Here, we develop a modified FQI (FQImod) for coastal Louisiana wetlands and verify it using 12 years of monitoring data from...
MODFLOW-style parameters in underdetermined parameter estimation
Marco D. D’Oria, Michael N. Fienen
2012, Groundwater (50) 149-153
In this article, we discuss the use of MODFLOW-Style parameters in the numerical codes MODFLOW_2005 and MODFLOW_2005-Adjoint for the definition of variables in the Layer Property Flow package. Parameters are a useful tool to represent aquifer properties in both codes and are the only option available in the adjoint version. Moreover, for overdetermined parameter...