Charles N. Alpers
2017, Book chapter, Encyclopedia of geochemistry
No abstract available....
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Publication Extents
Not all publications have extents, not all extents are completely accurateJohan T. du Toit, Paul C. Cross, Marion Valeix
2017, Book chapter, Rangeland Systems
On rangelands the livestock–wildlife interface is mostly characterized by management actions aimed at controlling problems associated with competition, disease, and depredation. Wildlife communities (especially the large vertebrate species) are typically incompatible with agricultural development because the opportunity costs of wildlife conservation are unaffordable except in arid and semi-arid regions. Ecological...
Deanna D. Strohm, Phaedra E. Budy, Todd A. Crowl
2017, Transactions of the American Fisheries Society (146) 732-743
Stream habitat restoration and supplemental stocking of hatchery-reared fish have increasingly become key components of recovery plans for imperiled freshwater fish; however, determining when to discontinue stocking efforts, prioritizing restoration areas, and evaluating restoration success present a conservation challenge. In this study, we demonstrate that otolith microchemistry is an effective...
Jens Frydenvang, Patrick J. Gasda, Joel A. Hurowitz, John P. Grotzinger, Roger C. Wiens, Horton E. Newsom, Ken S. Edgett, Jessica Watkins, John C. Bridges, Sylvestre Maurice, Martin R. Fisk, Jeffrey R. Johnson, William Rapin, Nathan Stein, Sam M. Clegg, S. P. Schwenzer, C. Bedford, P. Edwards, Nicolas Mangold, Agnes Cousin, Ryan B. Anderson, Valerie Payre, David Vaniman, David Blake, Nina L. Lanza, Sanjeev Gupta, Jason K. Van Beek, Violaine Sautter, Pierre-Yves Meslin, Melissa Rice, Ralf Milliken, Ralf Gellert, Lucy Thompson, Ben C. Clark, Dawn Y. Sumner, Abigail A. Fraeman, Kjartan M Kinch, Morten B. Madsen, Igor Mitofranov, Insoo Jun, Fred J. Calef, Ashwin R. Vasavada
2017, Geophysical Research Letters (44) 4716-4724
Diagenetic silica enrichment in fracture-associated halos that crosscut lacustrine and unconformably overlying aeolian sedimentary bedrock is observed on the lower north slope of Aeolis Mons in Gale crater, Mars. The diagenetic silica enrichment is colocated with detrital silica enrichment observed in the lacustrine bedrock yet extends into a considerably younger,...
Tomáš Navrátil, Martin Simecek, James B. Shanley, Jan Rohovec, Maria Hojdova, Jakub Houska
2017, Science of the Total Environment (586) 1192
We assessed > 100 years of mercury (Hg) pollution recorded in the tree rings of Scots Pine near a Czech chlor-alkali plant operating since 1941. Hg concentrations in tree rings increased with the launching of plant operations and decreased when Hg emissions decreased in 1975 due to an upgrade in production technology....
Carson J. Watkins, Tyler J. Ross, Michael C. Quist, Ryan S. Hardy
2017, Transactions of the American Fisheries Society (146) 703-715
Extensive water development in large rivers has precipitated many negative ecological effects on native fish populations. Mitigation for such development often focuses on restoring biological integrity through remediation of the physical and chemical properties of regulated rivers. However, evaluating and defining the success of those programs can be difficult. We...
Kathryn E. Clark, James B. Shanley, Martha A. Scholl, Nicolas Perdrial, Julia N. Perdrial, Alain F. Plante, William H. McDowell
2017, Water Resources Research (53) 3695-3712
Droughts, which can strongly affect both hydrologic and biogeochemical systems, are projected to become more prevalent in the tropics in the future. We assessed the effects of an extreme drought during 2015 on stream water composition in the Luquillo Mountains of Puerto Rico. We demonstrated that drought base flow in...
John A. Sweka, Lori A. Davis, Tyler Wagner
2017, Transactions of the American Fisheries Society (146) 744-752
Stream-dwelling salmonids that spawn in the fall generally experience their lowest survival during the fall and winter due to behavioral changes associated with spawning and energetic deficiencies during this time of year. We used data from Brook Trout Salvelinus fontinalis and Brown Trout Salmo trutta implanted with radio transmitters in...
Kendra Spence Cheruvelil, Shuai Yuan, Katherine E. Webster, Pang-Ning Tan, Jean-Francois Lapierre, Sarah M. Collins, C. Emi Fergus, Caren E. Scott, Emily Norton Henry, Patricia A. Soranno, Christopher T. Filstrup, Tyler Wagner
2017, Ecology and Evolution (7) 3046-3058
Understanding broad-scale ecological patterns and processes often involves accounting for regional-scale heterogeneity. A common way to do so is to include ecological regions in sampling schemes and empirical models. However, most existing ecological regions were developed for specific purposes, using a limited set of geospatial features and irreproducible methods. Our...
Paul D. Scheerer, James T. Peterson, Shaun Clements
2017, Northwestern Naturalist (98) 39-47
The Millicoma Dace Rhinichthys cataractae is a form of Longnose Dace endemic to the Coos River drainage in southwestern Oregon. Sparse species records in the Oregon State University Ichthyology Collection and database and infrequent recent encounters prompted surveys to assess the current status and distribution of the species. In 2014, we surveyed...
Amy E. Kleckner, Evangelos Kakouros, A. Robin Stewart
2017, Limnology and Oceanography: Methods (15) 363-371
A safe, practical, and accurate method for the determination of selenium (Se) in range of environmental samples was developed. Small sample masses, 5–20 mg, were amended with 82Se enriched isotope for the isotope dilution (ID), preceding a multi-step wet digestion with nitric acid (HNO3) and hydrogen peroxide (H2O2). Samples were...
Stephen B. Gingerich, Clifford I. Voss, Adam G. Johnson
2017, Journal of Hydrology (551) 676-688
An unprecedented set of hydrologic observations was collected after the Dec 2008 seawater-flooding event on Roi-Namur, Kwajalein Atoll, Republic of the Marshall Islands. By two days after the seawater flooding that occurred at the beginning of dry season, the observed salinity of water withdrawn by the island’s main skimming...
Brian M. Hynek, Gaetano Di Achille
2017, Scientific Investigations Map 3356
Introduction and BackgroundThe Meridiani Planum region of Mars—originally named due to its proximity to the Martian prime meridian—contains a variety of geologic units, including those that are crater‑related, that span the Early Noachian to Late Amazonian Epochs. Mars Global Surveyor (MGS) data indicate this area contains extensive layered deposits, some...
Harland L. Goldstein, George N. Breit, Richard L. Reynolds
2017, Journal of Arid Environments (140) 50-66
Saline-surface crusts and their compositions at ephemeral, dry, and drying lakes are important products of arid-land processes. Detailed understanding is lacking, however, about interactions among locally variable hydrogeologic conditions, compositional control of groundwater on vadose zone and surface salts, and dust composition. Chemical and physical data from groundwater, sediments, and...
Jonathan A. O’Donnell, Christian E. Zimmerman, Michael P. Carey, Joshua C. Koch
2017, Alaska Park Science (16) 47-49
No abstract available....
Austin A. Rizzo, Stuart A. Welsh, Patricia A. Thompson
2017, North American Journal of Fisheries Management (37) 16-22
Photogrammetry, a technique to obtain measurements from photographs, may be a valid method for measuring lengths of rare, threatened, or endangered species. Photogrammetric methods of measurement are nonintrusive and reduce the possibility of physical damage or physiological stress associated with the capture and handling of individuals. We evaluated precision and...
Pan Chen, Benjamin B. Mirus, Ning Lu, Jonathan W. Godt
2017, Journal of Geotechnical and Geoenvironmental Engineering (143)
Hydraulic hysteresis, including capillary soil water retention (SWR), air entrapment SWR, and hydraulic conductivity, is a common phenomenon in unsaturated soils. However, the influence of hydraulic hysteresis on suction stress, and subsequently slope stability, is generally ignored. This paper examines the influence of each of these three...
Kaitlynn J. Fernelius, Matthew D. Madsen, Bryan Hopkins, Sheel Bansal, Val J. Anderson, Dennis L. Eggett, Bruce A. Roundy
2017, Journal of Arid Environments (144) 98-109
Woody plant encroachment can increase nutrient resources in the plant-mound zone. After a fire, this zone is often found to be water repellent. This study aimed to understand the effects of post-fire water repellency on soil water and inorganic nitrogen and their effects on plant growth of the introduced annual...
Kenneth G. Rice, Paul Beier, Tim Breault, Beth A. Middleton, Myron A. Peck, John M. Tirpak, Mary Ratnaswamy
2017, Report
In 2008, the U.S. Congress authorized the establishment of the National Climate Change and Wildlife Science Center (NCCWSC) within the U.S. Department of Interior (DOI). Housed administratively within the U.S. Geological Survey (USGS), NCCWSC is part of the DOI’s ongoing mission to meet the challenges of...
Debbie W. Gordon, Gerard Gonthier
2017, Scientific Investigations Report 2017-5017
The U.S. Geological Survey conducted a study, in cooperation with the Georgia Environmental Protection Division, to define the hydrologic properties of the Claiborne aquifer and evaluate its connection with the Upper Floridan aquifer in southwest Georgia. The effort involved collecting and compiling hydrologic data from the aquifer in subarea 4...
Warren W. Wood, J.K. Bohlke
2017, Groundwater (55) 199-207
Subsurface brines with high nitrate (NO3−) concentration are common in desert environments as atmospheric nitrogen is concentrated by the evaporation of precipitation and little nitrogen uptake. However, in addition to having an elevated mean concentration of ∼525 mg/L (as N), NO3− in the coastal sabkhas of Abu Dhabi is enriched...
John Franco Saraceno, James B. Shanley, Bryan D. Downing, Brian A. Pellerin
2017, Limnology and Oceanography: Methods (15) 408-416
In situ fluorescent dissolved organic matter (fDOM) measurements have gained increasing popularity as a proxy for dissolved organic carbon (DOC) concentrations in streams. One challenge to accurate fDOM measurements in many streams is light attenuation due to suspended particles. Downing et al. (2012) evaluated the need for corrections to compensate...
Brett A. Poulin, Joseph N. Ryan, Kathryn L. Nagy, Aron Stubbins, Thorsten Dittmar, William H. Orem, David P. Krabbenhoft, George R. Aiken
2017, Environmental Science & Technology (51) 3630-3639
Sulfate inputs to the Florida Everglades stimulate sulfidic conditions in freshwater wetland sediments that affect ecological and biogeochemical processes. An unexplored implication of sulfate enrichment is alteration of the content and speciation of sulfur in dissolved organic matter (DOM), which influences the reactivity of DOM with trace metals. Here, we...
Laszlo P. Keszthelyi, Justin Hagerty, Amanda Bowers, Karl J. Ellefsen, Trude King, Ian Ridley, David Trilling, Nicholas Moskovitz, Will Grundy
2017, Open-File Report 2017-1041
This study was undertaken to determine if the U.S. Geological Survey’s process for conducting mineral resource assessments on Earth can be applied to asteroids. Successful completion of the assessment, using water and iron resources to test the workflow, has resulted in identification of the minimal adjustments required to conduct...
Elizabeth A. Hittle
2017, Open-File Report 2016-1206
Bacteria-driven restrictions and (or) advisories on swimming at beaches in Presque Isle State Park (PISP), Erie, Pennsylvania, can occur during the summer months. One of the suspected sources of bacteria is sediment. A terrestrial sediment source to the west of PISP is Walnut Creek, which discharges to Lake Erie about...