Publications
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Controls on the chemical composition of saline surface crusts and emitted dust from a wet playa in the Mojave Desert (USA)
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 salts r
Authors
Harland L. Goldstein, George N. Breit, Richard L. Reynolds
Density estimates of monarch butterflies overwintering in central Mexico
Given the rapid population decline and recent petition for listing of the monarch butterfly (Danaus plexippus L.) under the Endangered Species Act, an accurate estimate of the Eastern, migratory population size is needed. Because of difficulty in counting individual monarchs, the number of hectares occupied by monarchs in the overwintering area is commonly used as a proxy for population size, whic
Authors
Wayne E. Thogmartin, James E. Diffendorfer, Laura Lopez-Hoffman, Karen Oberhauser, John M. Pleasants, Brice X. Semmens, Darius J. Semmens, Orley R. Taylor, Ruscena Wiederholt
A 130,000-year-old archaeological site in southern California, USA
The earliest dispersal of humans into North America is a contentious subject, and proposed early sites are required to meet the following criteria for acceptance: (1) archaeological evidence is found in a clearly defined and undisturbed geologic context; (2) age is determined by reliable radiometric dating; (3) multiple lines of evidence from interdisciplinary studies provide consistent results; a
Authors
Steven R. Holen, Thomas A. Deméré, Daniel C. Fisher, Richard Fullagar, James B. Paces, George T. Jefferson, Jared M. Beeton, Richard A. Cerutti, Adam N. Rountrey, Lawrence Vescera, Kathleen A. Holen
Thematic accuracy assessment of the 2011 National Land Cover Database (NLCD)
Accuracy assessment is a standard protocol of National Land Cover Database (NLCD) mapping. Here we report agreement statistics between map and reference labels for NLCD 2011, which includes land cover for ca. 2001, ca. 2006, and ca. 2011. The two main objectives were assessment of agreement between map and reference labels for the three, single-date NLCD land cover products at Level II and Level I
Authors
James Wickham, Stephen V. Stehman, Leila Gass, Jon Dewitz, Daniel G. Sorenson, Brian J. Granneman, Richard V. Poss, Lori Anne Baer
The effect of lithology on valley width, terrace distribution, and coarse sediment provenance in a tectonically stable catchment with flat-lying stratigraphy
How rock resistance or erodibility affects fluvial landforms and processes is an outstanding question in geomorphology that has recently garnered attention owing to the recognition that the erosion rates of bedrock channels largely set the pace of landscape evolution. In this work, we evaluate valley width, terrace distribution, and sediment provenance in terms of reach scale variation in litholog
Authors
Amanda Keen-Zebert, Mark R. Hudson, Stephanie L. Shepherd, Evan A. Thaler
Vertebrate paleontology, stratigraphy, and paleohydrology of Tule Springs Fossil Beds National Monument, Nevada (USA)
Tule Springs Fossil Beds National Monument (TUSK) preserves 22,650 acres of the upper Las Vegas Wash in the northern Las Vegas Valley (Nevada, USA). TUSK is home to extensive and stratigraphically complex groundwater discharge (GWD) deposits, called the Las Vegas Formation, which represent springs and desert wetlands that covered much of the valley during the late Quaternary. The GWD deposits reco
Authors
Kathleen B. Springer, Jeffery S. Pigati, Eric Scott
A synthesis of thermokarst lake water balance in high-latitude regions of North America from isotope tracers
Numerous studies utilizing remote sensing imagery and other methods have documented that thermokarst lakes are undergoing varied hydrological transitions in response to recent climate changes, from surface area expansion to drainage and evaporative desiccation. Here, we provide a synthesis of hydrological conditions for 376 lakes of mainly thermokarst origin across high-latitude North America. We
Authors
Lauren A. MacDonald, Brent B. Wolfe, Kevin W. Turner, Lesleigh Anderson, Christopher D. Arp, Jean Birks, Frédéric Bouchard, Thomas W.D. Edwards, Nicole Farquharson, Roland I. Hall, Ian McDonald, Biljana Narancic, Chantal Ouimet, Reinhard Pienitz, Jana Tondu, Hilary White
Eruptive history, geochronology, and post-eruption structural evolution of the late Eocene Hall Creek Caldera, Toiyabe Range, Nevada
The magmatic, tectonic, and topographic evolution of what is now the northern Great Basin remains controversial, notably the temporal and spatial relation between magmatism and extensional faulting. This controversy is exemplified in the northern Toiyabe Range of central Nevada, where previous geologic mapping suggested the presence of a caldera that sourced the late Eocene (34.0 mega-annum [Ma])
Authors
Joseph Colgan, Christopher D. Henry
Computer modelling for ecosystem service assessment
Computer models are simplified representations of the environment that allow biophysical, ecological, and/or socio-economic characteristics to be quantified and explored. Modelling approaches differ from mapping approaches (Chapter 5) as (i) they are not forcibly spatial (although many models do produce spatial outputs); (ii) they focus on understanding and quantifying the interactions between dif
Authors
Robert Dunford, Paula Harrison, Kenneth J. Bagstad
DOI/GTN-P Climate and active-layer data acquired in the National Petroleum Reserve–Alaska and the Arctic National Wildlife Refuge, 1998–2015
This report provides data collected by the climate monitoring array of the U.S. Department of the Interior on Federal lands in Arctic Alaska over the period August 1998 to July 2015; this array is part of the Global Terrestrial Network for Permafrost (DOI/GTN-P). In addition to presenting data, this report also describes monitoring, data collection, and quality-control methods. The array of 16 mon
Authors
Frank E. Urban, Gary D. Clow
A method to assess the population-level consequences of wind energy facilities on bird and bat species
For this study, a methodology was developed for assessing impacts of wind energy generation on populations of birds and bats at regional to national scales. The approach combines existing methods in applied ecology for prioritizing species in terms of their potential risk from wind energy facilities and estimating impacts of fatalities on population status and trend caused by collisions with wind
Authors
James E. Diffendorfer, Julie A. Beston, Matthew D. Merrill, Jessica C. Stanton, M.D. Corum, Scott R. Loss, Wayne E. Thogmartin, Douglas H. Johnson, Richard A. Erickson, Kevin W. Heist
Expanding the role of reactive transport models in critical zone processes
Models test our understanding of processes and can reach beyond the spatial and temporal scales of measurements. Multi-component Reactive Transport Models (RTMs), initially developed more than three decades ago, have been used extensively to explore the interactions of geothermal, hydrologic, geochemical, and geobiological processes in subsurface systems. Driven by extensive data sets now availabl
Authors
Li Li, Kate Maher, Alexis Navarre-Sitchler, Jennifer Druhan, Christof Meile, Corey Lawrence, Joel Moore, Julia Perdrial, Pamela Sullivan, Aaron Thompson, Lixin Jin, Edward W. Bolton, Susan L. Brantley, William E. Dietrich, K. Ulrich Mayer, Carl Steefel, Albert J. Valocchi, John M. Zachara, Benjamin D. Kocar, Jennifer McIntosh, Benjamin M. Tutolo, Mukesh Kumar, Eric Sonnenthal, Chen Bao, Joe Beisman