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Not all publications have extents, not all extents are completely accurate
Combining multiphase groundwater flow and slope stability models to assess stratovolcano flank collapse in the Cascade Range
Jessica L. Ball, Joshua M. Taron, Mark E. Reid, Shaul Hurwitz, Carol A. Finn, Paul A. Bedrosian
2018, Journal of Geophysical Research Solid Earth (123) 2787-2805
Hydrothermal alteration can create low‐permeability zones, potentially resulting in elevated pore‐fluid pressures, within a volcanic edifice. Strength reduction by rock alteration and high pore‐fluid pressures have been suggested as a mechanism for edifice flank instability. Here we combine numerical models of multiphase heat transport and groundwater...
Long-term population dynamics and conservation risk of migratory bull trout in the upper Columbia River basin
Ryan Kovach, Jonathan Armstrong, David Schmetterling, Robert Al-Chokhachy, Clint C. Muhlfeld
2018, Canadian Journal of Fisheries and Aquatic Sciences (75) 1960-1968
We used redd count data from 88 bull trout (Salvelinus confluentus) populations in the upper Columbia River basin to quantify local and regional patterns in population dynamics, including adult abundance, long-term trend, and population synchrony. We further used this information to assess conservation risk of metapopulations using eight population dynamic...
Managing an invasive corallimorph at Palmyra Atoll National Wildlife Refuge, Line Islands, Central Pacific
Thierry M. Work, Greta S. Aeby, Benjamin P. Neal, Nichole N. Price, Eric Conklin, Amanda Pollock
2018, Biological Invasions (20) 2197-2208
In 2007, a phase shift from corals to corallimorpharians (CM) centered around a shipwreck was documented at Palmyra Atoll, Line Islands. Subsequent surveys revealed CM to be overgrowing the reef benthos, including corals and coralline algae, potentially placing coral ecosystems in the atoll at risk. This prompted the U.S. Fish...
Shifting stream planform state decreases stream productivity yet increases riparian animal production
Michael P. Venarsky, David M. Walters, Robert O. Hall Jr., Bridget Livers, Ellen Wohl
2018, Oecologia (187) 167-180
In the Colorado Front Range (USA), disturbance history dictates stream planform. Undisturbed, old-growth streams have multiple channels and large amounts of wood and depositional habitat. Disturbed streams (wildfires and logging < 200 years ago) are single-channeled with mostly erosional habitat. We tested how these opposing stream states influenced organic matter, benthic macroinvertebrate...
The role of frozen soil in groundwater discharge predictions for warming alpine watersheds
Sarah G. Evans, Shemin Ge, Clifford I. Voss, Noah P. Molotch
2018, Water Resources Research (54) 1599-1615
Climate warming may alter the quantity and timing of groundwater discharge to streams in high alpine watersheds due to changes in the timing of the duration of seasonal freezing in the subsurface and snowmelt recharge. It is imperative to understand the effects of seasonal freezing and recharge on groundwater discharge...
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...
Groundwater quality in the Mokelumne, Cosumnes, and American River Watersheds, Sierra Nevada, California
Miranda S. Fram, Jennifer L. Shelton
2018, Open-File Report 2018-1047
Groundwater provides more than 40 percent of California’s drinking water. To protect this vital resource, the State of California created the Groundwater Ambient Monitoring and Assessment (GAMA) Program. The GAMA Program’s Priority Basin Project assesses the quality of groundwater resources used for drinking water supply and increases public access to...
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...
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...
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...
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...
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...
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...
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...
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...
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...
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...
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...