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Publication Extents

Not all publications have extents, not all extents are completely accurate
Atypical pit craters on Mars: new insights from THEMIS, CTX and HiRISE observations
Glen Cushing, Chris H. Okubo, Timothy N. Titus
2015, Journal of Geophysical Research (120) 1023-1043
More than 100 pit craters in the Tharsis region of Mars exhibit morphologies, diameters and thermal behaviors that diverge from the much larger bowl-shaped pit craters that occur in most regions across Mars. These Atypical Pit Craters (APCs) generally have sharp and distinct rims, vertical or overhanging walls that extend...
AMDTreat 5.0+ with PHREEQC titration module to compute caustic chemical quantity, effluent quality, and sludge volume
Charles A. Cravotta III, Brent P Means, Willam Arthur, Robert M McKenzie, David L. Parkhurst
2015, Mine Water and the Environment (34) 136-152
Alkaline chemicals are commonly added to discharges from coal mines to increase pH and decrease concentrations of acidity and dissolved aluminum, iron, manganese, and associated metals. The annual cost of chemical treatment depends on the type and quantities of chemicals added and sludge produced. The AMDTreat computer program, initially developed...
The interaction of intraspecific competition and habitat on individual diet specialization: a near range-wide examination of sea otters
Seth D. Newsome, M. Tim Tinker, Verena A. Gill, Zachary N. Hoyt, Angela M. Doroff, Linda Nichol, James L. Bodkin
2015, Oecologia (178) 45-59
The quantification of individuality is a common research theme in the fields of population, community, and evolutionary ecology. The potential for individuality to arise is likely context-dependent, and the influence of habitat characteristics on its prevalence has received less attention than intraspecific competition. We examined individual diet specialization in 16...
Experimental dosing of wetlands with coagulants removes mercury from surface water and decreases mercury bioaccumulation in fish
Joshua T. Ackerman, Tamara E.C. Kraus, Jacob A. Fleck, David P. Krabbenhoft, William R. Horwarth, Sandra M. Bachand, Mark P. Herzog, C. Alex Hartman, Philip Bachand
2015, Environmental Science & Technology (49) 6304-6311
Mercury pollution is widespread globally, and strategies for managing mercury contamination in aquatic environments are necessary. We tested whether coagulation with metal-based salts could remove mercury from wetland surface waters and decrease mercury bioaccumulation in fish. In a complete randomized block design, we constructed nine experimental wetlands in California’s Sacramento–San...
From patterns to causal understanding: Structural equation modeling (SEM) in soil ecology
Nico Eisenhauer, Jeff R Powell, James B. Grace, Matthew A. Bowker
2015, Pedobiologia (58) 65-72
In this perspectives paper we highlight a heretofore underused statistical method in soil ecological research, structural equation modeling (SEM). SEM is commonly used in the general ecological literature to develop causal understanding from observational data, but has been more slowly adopted by soil ecologists. We provide some basic information on...
Inter-laboratory variation in the chemical analysis of acidic forest soil reference samples from eastern North America
Donald S. Ross, Scott W Bailiey, Russell D Briggs, Johanna Curry, Ivan J. Fernandez, Guinevere Fredriksen, Christine L. Goodale, Paul W. Hazlett, Paul R Heine, Chris E. Johnson, John T Larson, Gregory B. Lawrence, Randy K Kolka, Ouimet, D Pare, Daniel D. Richter, Charles D Shirmer, Richard A.F. Warby
2015, Ecosphere (6) 1-22
Long-term forest soil monitoring and research often requires a comparison of laboratory data generated at different times and in different laboratories. Quantifying the uncertainty associated with these analyses is necessary to assess temporal changes in soil properties. Forest soil chemical properties, and methods to measure these properties, often differ from...
Landscape characteristics influencing the genetic structure of greater sage-grouse within the stronghold of their range: a holistic modeling approach
Jeff R Row, Sara J. Oyler-McCance, Jennifer A. Fike, Michael S. O’Donnell, Kevin E. Doherty, Cameron L. Aldridge, Zachary H. Bowen, Brad C. Fedy
2015, Ecology and Evolution (5) 1955-1969
Given the significance of animal dispersal to population dynamics and geographic variability, understanding how dispersal is impacted by landscape patterns has major ecological and conservation importance. Speaking to the importance of dispersal, the use of linear mixed models to compare genetic differentiation with pairwise resistance derived from landscape resistance surfaces...
Dam-breach analysis and flood-inundation mapping for selected dams in Oklahoma City, Oklahoma, and near Atoka, Oklahoma
Molly J. Shivers, S. Jerrod Smith, Trevor S. Grout, Jason M. Lewis
2015, Scientific Investigations Report 2015-5052
Dams provide beneficial functions such as flood control, recreation, and storage of water supplies, but they also entail risk; dam breaches and resultant floods can cause substantial property damage and loss of life. The State of Oklahoma requires each owner of a high-hazard dam, which the Federal Emergency Management Agency...
Geologic and structural controls on rupture zone fabric: A field-based study of the 2010 Mw 7.2 El Mayor–Cucapah earthquake surface rupture
Orlando Teran, John L. Fletcher, Michael Oskin, Thomas Rockwell, Kenneth W. Hudnut, Ronald Spelz, Sinan Akciz, Ana Paula Hernandez-Flores, Alexander Morelan
2015, Geosphere (11) 899-920
We systematically mapped (scales >1:500) the surface rupture of the 4 April 2010 Mw (moment magnitude) 7.2 El Mayor-Cucapah earthquake through the Sierra Cucapah (Baja California, northwestern Mexico) to understand how faults with similar structural and lithologic characteristics control rupture zone fabric, which is here defined by the thickness, distribution,...
Structure, diversity, and biophysical properties of old-growth forestsin the Klamath region, USA
Phillip J. van Mantgem, Daniel A Starr
2015, Northwest Science (89) 170-181
The diverse old-growth forests in Klamath region of northern California and southern Oregon provide valuable ecosystem services (e.g., maintaining watersheds, wildlife habitat, recreation), but may be vulnerable to a wide range of stressors, including invasive species, disrupted disturbance regimes, and climatic change. Yet our understanding of how forest structure in...
Optimizing water depth for wetland-dependent wildlife could increase wetland restoration success, water efficiency, and water security
Christopher P. Nadeau, Courtney J. Conway
2015, Restoration Ecology (23) 292-300
Securing water for wetland restoration efforts will be increasingly difficult as human populations demand more water and climate change alters the hydrologic cycle. Minimizing water use at a restoration site could help justify water use to competing users, thereby increasing future water security. Moreover, optimizing water depth for focal species...
Hydrogeologic framework of the Santa Clara Valley, California
Randall T. Hanson
2015, Geosphere (11) 606-637
The hydrologic framework of the Santa Clara Valley in northern California was redefined on the basis of new data and a new hydrologic model. The regional groundwater flow systems can be subdivided into upper-aquifer and lower-aquifer systems that form a convergent flow system within a basin bounded by mountains...
Evidence of bottom-up limitations in nearshore marine systems based on otolith proxies of fish growth
Vanessa R. von Biela, Gordon H. Kruse, Franz J. Mueter, Bryan A. Black, David C. Douglas, Thomas E. Helser, Christian E. Zimmerman
2015, Marine Biology (162) 1019-1031
Fish otolith growth increments were used as indices of annual production at nine nearshore sites within the Alaska Coastal Current (downwelling region) and California Current (upwelling region) systems (~36–60°N). Black rockfish (Sebastes melanops) and kelp greenling (Hexagrammos decagrammus) were identified as useful indicators in pelagic and...
Life-stage-specific physiology defines invasion extent of a riverine fish
David J. Lawrence, David A. Beauchamp, Julian D. Olden
2015, Journal of Animal Ecology (84) 879-888
Many ecologists have called for mechanism-based investigations to identify the underlying controls on species distributions. Understanding these controls can be especially useful to construct robust predictions of how a species range may change in response to climate change or the extent to which a non-native species may...
Consequences of actively managing a small Bull Trout population in a fragmented landscape
Robert K. Al-Chokhachy, Sean Moran, Peter McHugh, Shana Bernall, Wade Fredenberg, Joseph M. DosSantos
2015, Transactions of the American Fisheries Society (144) 515-531
Habitat fragmentation, which affects many native salmonid species, is one of the major factors contributing to the declines in distribution and abundance of Bull Trout Salvelinus confluentus. Increasingly, managers are considering options to maintain and enhance the persistence of isolated local populations through active management strategies. Understanding the ecological consequences of...
Source limitation of carbon gas emissions in high-elevation mountain streams and lakes
John T. Crawford, Mark M. Dornblaser, Emily H. Stanley, David W. Clow, Robert G. Striegl
2015, Journal of Geophysical Research G: Biogeosciences (120) 952-964
Inland waters are an important component of the global carbon cycle through transport, storage, and direct emissions of CO2 and CH4 to the atmosphere. Despite predictions of high physical gas exchange rates due to turbulent flows and ubiquitous supersaturation of CO2—and perhaps also CH4—patterns of gas emissions are essentially undocumented...
Comparison of three preservation techniques for slowing dissolution of calcareous nannofossils in organic rich sediments
Ellen Seefelt, Jean Self-Trail, Arthur P. Schultz
2015, Micropaleontology (61) 149-164
In an attempt to halt or reduce dissolution of calcareous nannofossils in organic and/or pyrite-rich sediments, three different methods of short-term storage preservation were tested for efficacy: vacuum packing, argon gas replacement, and buffered water. Abundance counts of calcareous nannofossil assemblages over a six month period showed that none of...
Modelling the enigmatic Late Pliocene Glacial Event - Marine Isotope Stage M2
Aisling M. Dolan, Alan M. Haywood, Stephen J. Hunter, Julia C. Tindall, Harry J. Dowsett, Daniel J. Hill, Steven J. Pickering
2015, Global and Planetary Change (128) 47-60
The Pliocene Epoch (5.2 to 2.58 Ma) has often been targeted to investigate the nature of warm climates. However, climate records for the Pliocene exhibit significant variability and show intervals that apparently experienced a cooler than modern climate. Marine Isotope Stage (MIS) M2 (~ 3.3 Ma) is a globally recognisable cooling event that...
Minimizing marker mass and handling time when attaching radio-transmitters and geolocators to small songbirds
Henry M. Streby, Tara L. McAllister, Sean M. Peterson, Gunnar R. Kramer, Justin A. Lehman, David E. Andersen
2015, The Condor (117) 249-255
Radio-transmitters and light-level geolocators are currently small enough for use on songbirds weighing <15 g. Various methods are used to attach these markers to larger songbirds, but with small birds it becomes especially important to minimize marker mass and bird handling time. Here, we offer modifications to harness materials and...
Using Landsat imagery to detect, monitor, and project net landscape change
Ryan R. Reker, Terry L. Sohl, Alisa L. Gallant
2015, All Bird Bulletin (Spring 2015) 13-17
Detailed landscape information is a necessary component to bird habitat conservation planning. The U.S. Geological Survey (USGS) Earth Resources Observation and Science (EROS) Center has been providing information on the Earth’s surface for over 40 years via the continuous series of Landsat satellites. In addition to operating, processing, and disseminating...
Geolocators on Golden-winged Warblers do not affect migratory ecology
Sean M. Peterson, Henry M. Streby, Gunnar R. Kramer, Justin A. Lehman, David A. Buehler, David E. Andersen
2015, The Condor (117) 256-261
The use of light-level geolocators is increasingly common for connecting breeding and nonbreeding sites and identifying migration routes in birds. Until recently, the mass and size of geolocators precluded their use on songbird species weighing <12 g. Reducing the mass of geolocators, such as by shortening or eliminating the light...
Population connectivity of endangered Ozark big-eared bats (Corynorhinus townsendii ingens)
Dana N. Lee, Richard C. Stark, William L. Puckette, Meredith J. Hamilton, David M. Leslie Jr., Ronald A. Van Den Bussche
2015, Journal of Mammalogy (96) 522-530
The endangered Ozark big-eared bat (Corynorhinus townsendii ingens) is restricted to eastern Oklahoma and western and north-central Arkansas, where populations may be susceptible to losses of genetic variation due to patchy distribution of colonies and potentially small effective population sizes. We used mitochondrial D-loop DNA sequences and 15 nuclear microsatellite...
Evaluation of angler reporting accuracy in an off-site survey to estimate statewide steelhead harvest
J. L. McCormick, D. Whitney, D. J. Schill, Michael C. Quist
2015, Fisheries Management and Ecology (22) 134-142
Accuracy of angler-reported data on steelhead, Oncorhynchus mykiss (Walbaum), harvest in Idaho, USA, was quantified by comparing data recorded on angler harvest permits to the numbers that the same group of anglers reported in an off-site survey. Anglers could respond to the off-site survey using mail or Internet; if they did not...