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Page 1033, results 25801 - 25825

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Publication Extents

Not all publications have extents, not all extents are completely accurate
Pinyon and juniper encroachment into sagebrush ecosystems impacts distribution and survival of greater sage-grouse
Peter S. Coates, Brian G. Prochazka, Mark A. Ricca, K. Benjamin Gustafson, Pilar T. Ziegler, Michael L. Casazza
2017, Rangeland Ecology and Management (70) 25-38
In sagebrush (Artemisia spp.) ecosystems, encroachment of pinyon (Pinus spp.) and juniper (Juniperus spp.; hereafter, “pinyon-juniper”) trees has increased dramatically since European settlement. Understanding the impacts of this encroachment on behavioral decisions, distributions, and population dynamics of greater sage-grouse (Centrocercus urophasianus) and other sagebrush obligate species could help benefit sagebrush...
Climatic controls on the global distribution, abundance, and species richness of mangrove forests
Michael J. Osland, Laura C. Feher, Kereen Griffith, Kyle C. Cavanaugh, Nicholas M. Enwright, Richard H. Day, Camille L. Stagg, Ken W. Krauss, Rebecca J. Howard, James B. Grace, Kerrylee Rogers
2017, Ecological Monographs (87) 341-359
Mangrove forests are highly productive tidal saline wetland ecosystems found along sheltered tropical and subtropical coasts. Ecologists have long assumed that climatic drivers (i.e., temperature and rainfall regimes) govern the global distribution, structure, and function of mangrove forests. However, data constraints have hindered the quantification of direct climate-mangrove linkages in...
Estimating the settling velocity of bioclastic sediment using common grain-size analysis techniques
Michael V. W. Cuttler, Ryan J. Lowe, James L. Falter, Daniel D. Buscombe
2017, Sedimentology (64) 987-1004
Most techniques for estimating settling velocities of natural particles have been developed for siliciclastic sediments. Therefore, to understand how these techniques apply to bioclastic environments, measured settling velocities of bioclastic sedimentary deposits sampled from a nearshore fringing reef in Western Australia were compared with settling velocities calculated using results from...
Spatial and temporal patterns of dissolved organic matter quantity and quality in the Mississippi River Basin, 1997–2013
Sarah M. Stackpoole, Edward G. Stets, David W. Clow, Douglas A. Burns, George R. Aiken, Brent T. Aulenbach, Irena F. Creed, Robert M. Hirsch, Hjalmar Laudon, Brian A. Pellerin, Robert G. Striegl
2017, Hydrological Processes (31) 902-915
Recent studies have found insignificant or decreasing trends in time-series dissolved organic carbon (DOC) datasets, questioning the assumption that long-term DOC concentrations in surface waters are increasing in response to anthropogenic forcing, including climate change, land use, and atmospheric acid deposition. We used the weighted regressions on time, discharge, and...
Shallow water benthic imaging and substrate characterization using recreational-grade sidescan-sonar
Daniel D. Buscombe
2017, Environmental Modelling and Software 1-18
In recent years, lightweight, inexpensive, vessel-mounted ‘recreational grade’ sonar systems have rapidly grown in popularity among aquatic scientists, for swath imaging of benthic substrates. To promote an ongoing ‘democratization’ of acoustical imaging of shallow water environments, methods to carry out geometric and radiometric correction and georectification of sonar echograms are...
Fitful and protracted magma assembly leading to a giant eruption, Youngest Toba Tuff, Indonesia
Mary R. Reid, Jorge A. Vazquez
2017, Geochemistry, Geophysics, Geosystems (18) 156-177
The paroxysmal eruption of the 74 ka Youngest Toba Tuff (YTT) of northern Sumatra produced an extraordinary 2800 km3 of non-welded to densely welded ignimbrite and co-ignimbrite ash-fall. We report insights into the duration of YTT magma assembly obtained from ion microprobe U-Th and U-Pb dates, including continuous age spectra...
Forest restoration at Redwood National Park: Exploring prescribed fire alternatives to second-growth management: A case study
Eamon Engber, Jason Teraoka, Phillip J. van Mantgem
2017, Conference Paper, Proceedings of the Coast Redwood Science Symposium
Almost half of Redwood National Park is comprised of second-growth forests characterized by high stand density, deficient redwood composition, and low understory biodiversity. Typical structure of young redwood stands impedes the recovery of old-growth conditions, such as dominance of redwood (Sequoia sempervirens (D. Don) Endl.), distinct canopy layers and diverse...
Engaging the user community for advancing societal applications of the Surface Water Ocean Topography mission
Faisal Hossain, Margaret Srinivasan, Craig Peterson, Alice Andral, Ed Beighley, Eric Anderson, Rashied Amini, Charon Birkett, David M. Bjerklie, Cheryl Ann Blain, Selma Cherchali, Cedric H. David, Bradley D. Doorn, Jorge Escurra, Lee-Lueng Fu, Chris Frans, John W. Fulton, Subhrendu Gangopadhyay, Subimal Ghosh, Colin Gleason, Marielle Gosset, Jessica Hausman, Gregg Jacobs, John W. Jones, Yasir Kaheil, Benoit Laignel, Patrick Le Moigne, Li Li, Fabien Lefevre, Mason Jr., Amita Mehta, Abhijit Mukherjee, Anthony Nguy-Robertson, Sophie Ricci, Adrien Paris, Tamlin Pavelsky, Nicolas Picot, Guy Schumann, Sudhir Shrestha, Pierre-Yves Le Traon, Eric Trehubenko
2017, Bulletin of the American Meteorological Society (November 2017) 285-290
Scheduled for launch in 2021, the Surface Water and Ocean Topography (SWOT) mission will be a truly unique mission that will provide high-temporal-frequency maps of surface water extents and elevation variations of global water bodies (lakes/reservoirs, rivers, estuaries, oceans, and sea ice) at higher spatial resolution than is available with...
No substitute for survival: Perturbation analyses using a Golden Eagle population model reveal limits to managing for take
Jason D. Tack, Barry R. Noon, Zachary H. Bowen, Lauren Strybos, Bradley C. Fedy
2017, Journal of Raptor Research (51) 258-272
Conserving populations of long-lived birds of prey, characterized by a slow life-history (e.g., high survival and low reproductive output), requires a thorough understanding of how variation in their vital rates differentially affects population growth. Stochastic population modeling provides a framework for exploring variation in complex life histories to better understand...
Molecular detection of avian influenza virus from sediment samples in waterfowl habitats on the Delmarva Peninsula, United States
Christine L. Densmore, Deborah D. Iwanowicz, Christopher Ottinger, Larry J. Hindman, Amanda Bessler, Luke R. Iwanowicz, Diann J. Prosser, Matt Whitbeck, Cindy P. Driscoll
2017, Avian Diseases (61) 520-525
Avian influenza viruses (AIV) affect many species of birds including waterfowl and may persist in sediment in aquatic habitats. Sediment samples were collected from two areas representative of prime migration and overwintering waterfowl habitat in Dorchester County, Maryland in the fall and winter of 2013–2014. Samples were screened for the...
Unifying population and landscape ecology with spatial capture-recapture
J. Andrew Royle, Angela K. Fuller, Christopher Sutherland
2017, Ecography (41) 444-456
Spatial heterogeneity in the environment induces variation in population demographic rates and dispersal patterns, which result in spatio‐temporal variation in density and gene flow. Unfortunately, applying theory to learn about the role of spatial structure on populations has been hindered by the lack of mechanistic spatial models and inability to...
Synthesis
Larry D. Hinzman, Peter Outridge, James M. Gamble, Lyman K. Thorsteinson, Sarah F. Trainor, John E. Walsh, Alexander Klepikov
2017, Book chapter, Adaptation actions for a changing arctic: Perspectives from the Bering Chukchi-Beaufort Region
The goal of this report is to examine changes in the current environment and living conditions of the coastal and tundra communities of northwestern Canada, northern Alaska, and the northern Far East of Russia – the Bering-Chukchi-Beaufort (BCB) region – and to understand how people are coping and adapting to...
Geophysical expression of buried range-front embayment structure: Great Sand Dunes National Park, Rio Grande rift, Colorado
Benjamin J. Drenth, V. J. Grauch, Chester A. Ruleman, Judith A Schenk
2017, Geosphere (13) 974-990
Great Sand Dunes National Park and Preserve (GRSA, Colorado) lies along the eastern margin of the San Luis Basin and the tectonically active Sangre de Cristo fault system that are part of the northern Rio Grande rift. GRSA lies within a prominent embayment in the range front where two separate...
Trends and sources of PAHs to urban lakes and streams
Peter C. Van Metre, Barbara Mahler
2017, Lakeline (37) 8-12
Over the past few decades, concentrations of polycyclic aromatic hydrocarbons (PAHs) have been increasing in the sediments of many U.S. urban lakes and streams. These upward trends contrast those of legacy pollutants, such as lead, PCBs, and DDT, which were restricted or banned in the 1970s. Trends of these legacy...
Growth of coast redwood and Douglas-fir following thinning in second-growth forests at Redwood National Park and Headwaters Forest Reserve
Phillip J. van Mantgem, Jason R. Teraoka, David H. LaFever, Laura Lalemand
2017, Conference Paper, Coast redwood science symposium—2016: Past successes and future direction. Proceedings of a workshop. Gen. Tech. Rep. PSW-GTR-258
Managers of second-growth forests at Redwood National Park and the Bureau of Land Management’s Headwaters Forest Reserve encourage the development of late seral forest characteristics using mechanical thinning, where competing vegetation is removed to promote growth of residual trees. Yet the ability to quantify and reliably predict outcomes of treatments...
Responses of a 64-story unique San Francisco, CA. building to four earthquakes and ambient motions
Mehmet Celebi, J. Hooper, Ron Klemencic
2017, Conference Paper, Proceedings of the 16th World Conference on Earthquake Engineering
We analyze the ambient and earthquake responses of a 64-story, instrumented, concrete core shear wall building in San Francisco, Calif. equipped with tuned sloshing liquid dampers (TSDs) and buckling restraining braces (BRBs). In an earlier paper [1], only ambient data were used to identify dynamic characteristics. Recently, the 72-channel instrumental...
Validation of NEXRAD data and models of bird migration stopover sites in the Northeast U.S.
Jeffrey J. Buler, James McLaren, Timothy Schreckengost, Jaclyn A. Smolinsky, Eric Walters, J. Andrew Arnold, Deanna K. Dawson
2017, Report
The national network of weather surveillance radars (NEXRAD) detects birds in flight, and has proven to be a useful remote-sensing tool for ornithological study. We used data collected during Fall 2008 to 2014 by 16 NEXRAD and four terminal Doppler weather radars (TDWR) in the northeastern U.S. to map and...
Changing water dynamics: The consequences of shifting snow, ice, and running water for ecosystems, people, and national forests in Alaska
Greg Hayward, Erik Johnson, Nathan Walker, Jeremy S. Littell, Julianne Thompson
2017, Report
Ecosystems of Alaska are rain-, snow-, and ice-driven systems. Consequently, the status of water—liquid or solid—strongly in uences resources and the people using ecosystem services. This document examines changes in water dynamics, the resulting consequences for ecosystems and people, and management options for adapting to changing conditions. Changes in snow, ice,...
Using science to inform management and improve biological conservation in the Desert Renewable Energy Conservation Plan
Todd Esque, Amy Fesnock-Parker, Brian Croft, Felicia Chen, Amy G. Vandergast
2017, Conference Paper, Transactions of the 82nd North American Wildlife and Natural Resources Conference
The Mojave and Colorado deserts of southern California have been viewed as vast wilderness since early exploration and, until recently, were considered the most untrammeled among western landscapes in the contiguous lower 48 states (United States Department of Agriculture 1893; Leu et al. 2008). However, the factors that define desert...
A report on genetic affinities and relatedness of Agassiz’s desert tortoises (Gopherus agassizii) at opposite ends of the Coachella Valley in California
Jeffrey E. Lovich, Taylor Edwards, Brian Kreiser, Shellie R. Puffer, Mickey Agha
2017, Report, Coachella Valley Multiple Species Habitat Conservation Plan/Natural Community Conservation Plan—2017 Annual Report
This report summarizes the results for mtDNA and STR genotyping of 41 desert tortoise (Gopherus agassizii) DNA samples from opposite sides of the Coachella Valley: one sample from the west side at the Mesa wind energy facility in the Whitewater Hills and the other from the mouth of Cottonwood Canyon...
Food-web structure in canyon and slope-associated fauna revealed by stable isotopes
Amanda W. J. Demopoulos, Jennifer P. McClain-Counts, Steve W. Ross, Sandra Brooke, Michael Rhode
2017, OCS Study BOEM 2017-060
Food webs and associated trophic linkages among organisms are central themes in ecology that provide insight into the structure and function of ecosystems. In the deep sea, food webs rely on particulate flux raining from surface waters for energy (Klages et al. 2003), except for chemosynthetic communities, which rely on...
Ecology of the Eastern Kingsnake (Lampropeltis getula) at Rainey Slough, Florida: A vanished Eden
J. Steve Godley, Brian J. Halstead, Roy W. McDiarmid
2017, Herpetological Monographs (31) 47-68
Eastern Kingsnakes (Lampropeltis getula) are an important component and predator in herpetofaunal communities, but many Eastern Kingsnake populations have declined precipitously in the last few decades, particularly in the southeastern United States. Here, we describe an intensive capture–mark–recapture study of L. getula conducted during 1974–1978 in a canal bank–Water Hyacinth (Eichhornia...
Impacts of mastication fuel treatments on California, USA, chaparral vegetation structure and composition
Teresa J. Brennan, Jon E. Keeley
2017, Fire Ecology (13) 120-138
Mechanical fuel treatments are a primary pre-fire strategy for potentially mitigating the threat of wildland fire, yet there is limited information on how they impact shrubland ecosystems. Our goal was to assess the impact of mechanical mastication fuel treatments on chaparral vegetation and to determine the extent to which they...
Climate change and collapsing thermal niches of Mexican endemic reptiles
Barry Sinervo, Donald B. Miles, Rafael A. Lara Resendiz, Jeffrey E. Lovich, Joshua R. Ennen, Johannes Muller, Robert D. Cooper, Philip C. Rosen, Joseph A. E. Stewart, Juan Carlos Santos, Jack W. Sites Jr., Paul Gibbons, Eric Goode, L. Scott Hillard, Luke Welton, Mickey Agha, Gabriel Caetano, Mercy Vaughn, Cristina Melendez Torres, Hector Gadsden, Gamaliel Castenada Gaytan, Patricia Galina-Tessaro, Fernando I. Valle Jimenez, Jorge H. Valdez-Villavicencio, Norberto Martinez Mendez, Guillermo Woolrich Pina, Victor Luja Molina, Anibal Diaz de la Vega Perez, Diego M. Arenas Moreno, Saul Dominguez Guerrero, Natalia Fierro, Scott Butterfield, Michael Westpha, Raymond B. Huey, William Mautz, Víctor Sánchez-Cordero, Fausto R. Mendez de la Cruz
2017, Report
Recent climate change should result in expansion of species to northern or high elevation range margins, and contraction at southern and low elevation margins due to extinction. Climate models predict dramatic extinctions and distributional shifts in the next century, but there are few ground-truths of these dire forecasts leading to...