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Page 820, results 20476 - 20500

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Not all publications have extents, not all extents are completely accurate
Functional group, biomass, and climate change effects on ecological drought in semiarid grasslands
Scott D. Wilson, Daniel R. Schlaepfer, John B. Bradford, William K. Lauenroth, Michael C. Duniway, Sonia A. Hall, Khishigbayar Jamiyansharav, Gensuo Jia, Ariuntsetseg Lkhagva, Seth M. Munson, David A. Pyke, Britta Tietjen
2018, Journal of Geophysical Research G: Biogeosciences (123) 1072-1085
Water relations in plant communities are influenced both by contrasting functional groups (grasses, shrubs) and by climate change via complex effects on interception, uptake and transpiration. We modelled the effects of functional group replacement and biomass increase, both of which can be outcomes of invasion and vegetation management, and climate...
The sedimentological characteristics and geochronology of the marshes of Dauphin Island, Alabama
Alisha M. Ellis, Christopher G. Smith, Marci E. Marot
2018, Open-File Report 2017-1165
In August 2015, scientists from the U.S. Geological Survey, St. Petersburg Coastal and Marine Science Center collected 11 push cores from the marshes of Dauphin Island and Little Dauphin Island, Alabama. Sample site environments included high marshes, low salt marshes, and salt flats, and varied in distance from the shoreline....
Natural and man-made hexavalent chromium, Cr(VI), in groundwater near a mapped plume, Hinkley, California—study progress as of May 2017, and a summative-scale approach to estimate background Cr(VI) concentrations
John A. Izbicki, Krishangi D. Groover
2018, Open-File Report 2018-1045
This report describes (1) work done between January 2015 and May 2017 as part of the U.S. Geological Survey (USGS) hexavalent chromium, Cr(VI), background study and (2) the summative-scale approach to be used to estimate the extent of anthropogenic (man-made) Cr(VI) and background Cr(VI) concentrations near the Pacific Gas and...
Model methodology for estimating pesticide concentration extremes based on sparse monitoring data
Aldo V. Vecchia
2018, Scientific Investigations Report 2017-5159
This report describes a new methodology for using sparse (weekly or less frequent observations) and potentially highly censored pesticide monitoring data to simulate daily pesticide concentrations and associated quantities used for acute and chronic exposure assessments, such as the annual maximum daily concentration. The new methodology is based on a...
Importance of growth rate on mercury and polychlorinated biphenyl bioaccumulation in fish
Jiajia Li, G. Douglas Haffner, Gordon Patterson, David M. Walters, Michael D. Burtnyk, Ken G. Drouillard
2018, Environmental Toxicology and Chemistry (37) 1655-1667
To evaluate the effect of fish growth on mercury (Hg) and polychlorinated biphenyl (PCB) bioaccumulation, a non–steady‐state toxicokinetic model, combined with a Wisconsin bioenergetics model, was developed to simulate Hg and PCB bioaccumulation in bluegill (Lepomis macrochirus). The model was validated by comparing observed with predicted Hg and PCB 180...
Delineation of the hydrogeologic framework of the Big Sioux aquifer near Sioux Falls, South Dakota, using airborne electromagnetic data
Kristen J. Valseth, Gregory C. Delzer, Curtis V. Price
2018, Scientific Investigations Map 3393
The U.S. Geological Survey, in cooperation with the City of Sioux Falls, South Dakota, began developing a groundwater-flow model of the Big Sioux aquifer in 2014 that will enable the City to make more informed water management decisions, such as delineation of areas of the greatest specific yield, which is...
Intraspecific niche models for ponderosa pine (Pinus ponderosa) suggest potential variability in population-level response to climate change
Kaitlin C. Maguire, Douglas J. Shinneman, Kevin M. Potter, Valerie D. Hipkins
2018, Systematic Biology (67) 965-978
Unique responses to climate change can occur across intraspecific levels, resulting in individualistic adaptation or movement patterns among populations within a given species. Thus, the need to model potential responses among genetically distinct populations within a species is increasingly recognized. However, predictive models of future distributions are regularly fit at...
Experimental whole-lake dissolved organic carbon increase alters fish diet and density but not growth or productivity
Shuntaro Koizumi, Nicola Craig, Jacob A. Zwart, Patrick T. Kelly, Jacob P. Ziegler, Brian Weidel, Stuart E. Jones, Christopher T. Solomon
2018, Canadian Journal of Fisheries and Aquatic Sciences (75) 1859-1867
Negative relationships between dissolved organic carbon (DOC) concentration and fish productivity have been reported from correlative studies across lakes, but to date there have not been experimental tests of these relationships. We increased the DOC concentration in a lake by 3.4 mg L-1, using a before-after control-impact (BACI) design, to...
Developing Foram-AMBI for biomonitoring in the Mediterranean: Species assignments to ecological categories
Frans Jorissen, Maria P. Nardelli, Ahuva Almogi-Labin, Christine Barras, Luisa Bergamin, Erica Bicchi, Akram El Kateb, Luciana Ferraro, Mary McGann, Caterina Morigi, Elena Romano, Anna Sabattini, Magali Schweizer, Silvia Spezzaferri
2018, Marine Micropaleontology (140) 33-45
Most environmental bio-monitoring methods using the species composition of marine faunas define the Ecological Quality Status of soft bottom ecosystems based on the relative proportions of species assigned to a limited number of ecological categories. In this study we analyse the distribution patterns...
Tributyltin: Advancing the science on assessing endocrine disruption with an unconventional endocrine-disrupting compound
Laurent Lagadic, Ioanna Katsiadaki, Ronald C. Biever, Patrick Guiney, Natalie Karouna-Renier, Tamar Schwarz, James P. Meador
2018, Book chapter, Reviews of environmental contamination and toxicology Volume 245
Tributyltin (TBT) has been recognized as an endocrine disrupting chemical (EDC) for several decades. However, only in the last decade, was its primary endocrine mechanism of action (MeOA) elucidated—interactions with the nuclear retinoid-X receptor (RXR), peroxisome proliferator-activated receptor γ (PPARγ), and their heterodimers. This molecular initiating event (MIE) alters a...
Annual variation in polychlorinated biphenyl (PCB) exposure in tree swallow (Tachycineta bicolor) eggs and nestlings at Great Lakes Restoration Initiative (GLRI) study sites
Christine M. Custer, Thomas W. Custer, Paul M. Dummer, Diana R. Goldberg, J. Christian Franson
2018, Environmental Monitoring and Assessment (190) 1-7
Tree swallow (Tachycineta bicolor) eggs and nestlings were collected from 16 sites across the Great Lakes to quantify normal annual variation in total polychlorinated biphenyl (PCB) exposure and to validate the sample size choice in earlier work. A sample size of five eggs or five nestlings per site...
Nitrogen concentrations and loads for the Connecticut River at Middle Haddam, Connecticut, computed with the use of autosampling and continuous measurements of water quality for water years 2009 to 2014
John R. Mullaney, Joseph W. Martin, Jonathan Morrison
2018, Scientific Investigations Report 2018-5006
The daily and annual loads of nitrate plus nitrite and total nitrogen for the Connecticut River at Middle Haddam, Connecticut, were determined for water years 2009 to 2014. The analysis was done with a combination of methods, which included a predefined rating curve method for nitrate plus nitrite and total...
Synthesis of tree swallow (Tachycineta bicolor) data for Beneficial Use Impairment (BUI) assessment at Wisconsin Areas of Concern
Christine M. Custer, Thomas W. Custer, Paul M. Dummer
2018, Open-File Report 2018-1032
Assessment of the “Bird or Animal Deformities or Reproductive Problems” Beneficial Use Impairment (BUI) can be accomplished by (1) comparing tissue concentrations to established background and Lowest Observable Effect Level (LOEL) for reproductive effects, or (2) directly measuring reproductive success at Areas of Concern (AOCs) and statistically comparing those rates...
Vegetation influences on infiltration in Hawaiian soils
Kimberlie Perkins, Jonathan D. Stock, John R. Nimmo
2018, Ecohydrology (11)
Changes in vegetation communities caused by removing trees, introducing grazing ungulates, and replacing native plants with invasive species have substantially altered soil infiltration processes and rates in Hawaii. These changes directly impact run-off, erosion, plant-available water, and aquifer recharge. We hypothesize that broad vegetation communities can be characterized by distributions...
Tagging and tracking
Michelle E. Lander, Andrew J. Westgate, Brian C. Balmer, James P. Reid, Michael J. Murray, Kristen L. Laidre
2018, Book chapter, CRC handbook of marine mammal medicine, 3rd edition
The number of stranding response facilities for marine mammals in the United States has increased over the past two decades, resulting in thousands of rehabilitated marine mammals released back into the wild (Geraci and Lounsbury 2005; Moore et al. 2007; Johnson and Mayer 2015; Simeone et al. 2015). All rehabilitated...
Challenges in complementing data from ground-based sensors with satellite-derived products to measure ecological changes in relation to climate – lessons from temperate wetland-upland landscapes
Alisa L. Gallant, Walter J. Sadinski, Jesslyn F. Brown, Gabriel B. Senay, Mark F. Roth
2018, Sensors (18) 1-38
Assessing climate-related ecological changes across spatiotemporal scales meaningful to resource managers is challenging because no one method reliably produces essential data at both fine and broad scales. We recently confronted such challenges while integrating data from ground- and satellite-based sensors for an assessment of four wetland-rich study areas in the...
Spatial and temporal variation in sources of atmospheric nitrogen deposition in the Rocky Mountains using nitrogen isotopes
Leora Nanus, Donald H. Campbell, Christopher M.B. Lehmann, M. Alisa Mast
2018, Atmospheric Environment (176) 110-119
Variation in source areas and source types of atmospheric nitrogen (N) deposition to high-elevation ecosystems in the Rocky Mountains were evaluated using spatially and temporally distributed N isotope data from atmospheric deposition networks for 1995-2016. This unique dataset links N in wet deposition and snowpack to mobile and stationary emissions...
Population estimates of the Endangered Hawaiʻi ʻĀkepa (Loxops coccineus) in different habitats on windward Mauna Loa
Seth W. Judge, Richard J. Camp, Patrick J. Hart, Scott T. Kichman
2018, Journal of Field Ornithology (89) 11-21
Endangered Hawai‘i ʻĀkepas (Loxops coccineus) are endemic to Hawai‘i island, where they occur in five spatially distinct populations. Data concerning the status and population trends of these unique Hawaiian honeycreepers are crucial for assessing the effectiveness of recovery and management actions. In 2016, we used point‐transect distance sampling to estimate...
Hydrologic assessment of the Edwin B. Forsythe National Wildlife Refuge
Christine M. Wieben, Mary M. Chepiga
2018, Scientific Investigations Report 2017-5088
The Edwin B. Forsythe National Wildlife Refuge (hereafter Forsythe refuge or the refuge) is situated along the central New Jersey coast and provides a mixture of freshwater and saltwater habitats for numerous bird, wildlife, and plant species. Little data and information were previously available regarding the freshwater dynamics that support...
Hydrogeology of, simulation of groundwater flow in, and potential effects of sea-level rise on the Kirkwood-Cohansey aquifer system in the vicinity of Edwin B. Forsythe National Wildlife Refuge, New Jersey
Alex R. Fiore, Lois M. Voronin, Christine M. Wieben
2018, Scientific Investigations Report 2017-5135
The Edwin B. Forsythe National Wildlife Refuge encompasses more than 47,000 acres of New Jersey coastal habitats, including salt marshes, freshwater wetlands, tidal wetlands, barrier beaches, woodlands, and swamps. The refuge is along the Atlantic Flyway and provides breeding habitat for fish, migratory birds, and other wildlife species. The refuge...
Analyzing floating and bedfast lake ice regimes across Arctic Alaska using 25 years of space-borne SAR imagery
Melanie Engram, Christopher D. Arp, Benjamin M. Jones, Olaniyi A Ajadi, Franz J Meyer
2018, Remote Sensing of Environment (209) 660-676
Late-winter lake ice regimes are controlled by water depth relative to maximum ice thickness (MIT). When MIT exceeds maximum water depth, lakes freeze to the bottom with bedfast ice (BI) and when MIT is less than maximum water depth lakes have floating ice (FI). Both airborne radar and space-borne synthetic aperture radar...
Development of Raman spectroscopy as a thermal maturity proxy in unconventional resource assessment
Grant A. Myers, Kelsey Kehoe, Paul C. Hackley
2018, Conference Paper, Proceedings of the Unconventional Resources Technology Conference
The objective of this study was to correlate shale hydrous pyrolysis with thermal maturity measurements based on solid bitumen reflectance (BRo) at the U.S. Geological Survey (USGS) and Raman microscopy (RM) at WellDog. In semi-blind Phase I, BRo values of the initial set of 8 samples were withheld prior to...
Spatial organization of the gastrointestinal microbiota in urban Canada geese
Sergei V. Drovetski, Michael O’Mahoney, Emma J. Ransome, Kenan O. Matterson, Haw Chuan Lim, Terry Chesser, Gary R. Graves
2018, Scientific Reports (8) 1-10
Recent reviews identified the reliance on fecal or cloacal samples as a significant limitation hindering our understanding of the avian gastrointestinal (gut) microbiota and its function. We investigated the microbiota of the esophagus, duodenum, cecum, and colon of a wild urban population of Canada goose (Branta canadensis). From a population...
Pilot testing and protocol development of giant applesnail suppression at Mandalay National Wildlife Refuge, Louisiana—July–October 2017
Jacoby Carter, Sergio Merino
2018, Open-File Report 2018-1041
This report provides an overview of the pilot study and description of the techniques developed for a future mitigation study of Pomacea maculata (giant applesnail) at the U.S. Fish and Wildlife Service Mandalay National Wildlife Refuge, Louisiana (MNWR). Egg mass suppression is a potential strategy for the mitigation of the...