From extreme pH to extreme temperature: An issue in honor of the geochemical contributions of Kirk Nordstrom, USGS hydrogeochemist
Kate M. Campbell, Philip L. Verplanck, R. Blaine McCleskey, Charles N. Alpers
2015, Applied Geochemistry (62) 1-2
This special issue of Applied Geochemistry honors Dr. D. Kirk Nordstrom, and his influential career spent primarily at the U.S. Geological Survey (USGS). This issue does not herald his retirement or other significant career milestone, but serves as a recognition of the impact his work has had on the field...
A method for estimating abundance of mobile populations using telemetry and counts of unmarked animals
Matthew Clement, Joy M O’Keefe, Brianne Walters
2015, Ecosphere (6)
While numerous methods exist for estimating abundance when detection is imperfect, these methods may not be appropriate due to logistical difficulties or unrealistic assumptions. In particular, if highly mobile taxa are frequently absent from survey locations, methods that estimate a probability of detection conditional on presence will generate biased abundance...
Validation of a spatial model used to locate fish spawning reef construction sites in the St. Clair–Detroit River system
Jason L. Fischer, David Bennion, Edward F. Roseman, Bruce A. Manny
2015, Journal of Great Lakes Research (41) 1178-1184
Lake sturgeon (Acipenser fulvescens) populations have suffered precipitous declines in the St. Clair–Detroit River system, following the removal of gravel spawning substrates and overfishing in the late 1800s to mid-1900s. To assist the remediation of lake sturgeon spawning habitat, three hydrodynamic models were integrated into a spatial model to identify...
Spatially explicit spectral analysis of point clouds and geospatial data
Daniel D. Buscombe
2015, Computers & Geosciences (86) 92-108
The increasing use of spatially explicit analyses of high-resolution spatially distributed data (imagery and point clouds) for the purposes of characterising spatial heterogeneity in geophysical phenomena necessitates the development of custom analytical and computational tools. In recent years, such analyses have become the basis of, for example, automated texture characterisation...
Climate and streamflow characteristics for selected streamgages in eastern South Dakota, water years 1945–2013
Galen K. Hoogestraat, John F. Stamm
2015, Scientific Investigations Report 2015-5146
Upward trends in precipitation and streamflow have been observed in the northeastern Missouri River Basin during the past century, including the area of eastern South Dakota. Some of the identified upward trends were anomalously large relative to surrounding parts of the northern Great Plains. Forcing factors for streamflow trends in...
Tidal and seasonal variations in calving flux observed with passive seismology
T.C. Bartholomaus, Christopher F. Larsen, Michael E. West, Shad O’Neel, Erin C. Pettit, Martin Truffer
2015, Journal of Geophysical Research F: Earth Surface (120) 2318-2337
The seismic signatures of calving events, i.e., calving icequakes, offer an opportunity to examine calving variability with greater precision than is available with other methods. Here using observations from Yahtse Glacier, Alaska, we describe methods to detect, locate, and characterize calving icequakes. We combine these icequake records with a coincident,...
A simplified, data-constrained approach to estimate the permafrost carbon–climate feedback
C.D. Koven, E.A.G. Schuur, C. Schädel, T. J. Bohn, E. J. Burke, G. Chen, X. Chen, P. Ciais, G. Grosse, J.W. Harden, D.J. Hayes, G. Hugelius, Elchin E. Jafarov, G. Krinner, P. Kuhry, D.M. Lawrence, A. H. MacDougall, Sergey S. Marchenko, A. David McGuire, Susan M. Natali, D.J. Nicolsky, David Olefeldt, S. Peng, V.E. Romanovsky, Kevin M. Schaefer, J. Strauss, Claire C. Treat, M. Turetsky
2015, Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences (373)
We present an approach to estimate the feedback from large-scale thawing of permafrost soils using a simplified, data-constrained model that combines three elements: soil carbon (C) maps and profiles to identify the distribution and type of C in permafrost soils; incubation experiments to quantify the rates of C lost after...
The vulnerability of Indo-Pacific mangrove forests to sea-level rise
Catherine E. Lovelock, Donald R. Cahoon, Daniel A. Friess, Glenn R. Guntenspergen, Ken W. Krauss, Ruth Reef, Kerrylee Rogers, Megan L. Saunders, Frida Sidik, Andrew Swales, Neil Saintilan, Le Xuan Thuyen, Tran Triet
2015, Nature (526) 559-563
Sea-level rise can threaten the long-term sustainability of coastal communities and valuable ecosystems such as coral reefs, salt marshes and mangroves. Mangrove forests have the capacity to keep pace with sea-level rise and to avoid inundation through vertical accretion of sediments, which allows them to maintain wetland soil elevations suitable...
Imaging the magmatic system of Mono Basin, California with magnetotellurics in three--dimensions
Jared R. Peacock, Margaret T. Mangan, Darcy McPhee, David A. Ponce
2015, Journal of Geophysical Research (120) 7273-7289
A three–dimensional (3D) electrical resistivity model of Mono Basin in eastern California unveils a complex subsurface filled with zones of partial melt, fluid–filled fracture networks, cold plutons, and regional faults. In 2013, 62 broadband magnetotelluric (MT) stations were collected in an array around southeastern Mono Basin from which a 3D...
Predictions of future ephemeral springtime waterbird stopover habitat availability under global change
Daniel R. Uden, Craig R. Allen, Andrew A. Bishop, Roger Grosse, Christopher F. Jorgensen, Theodore G. LaGrange, Randy G. Stutheit, Mark P. Vrtiska
2015, Ecosphere (6) 1-26
In the present period of rapid, worldwide change in climate and landuse (i.e., global change), successful biodiversity conservation warrants proactive management responses, especially for long-distance migratory species. However, the development and implementation of management strategies can be impeded by high levels of uncertainty and low levels of control over potentially...
LiDAR based prediction of forest biomass using hierarchical models with spatially varying coefficients
Chad Babcock, Andrew O. Finley, John B. Bradford, Randall K. Kolka, Richard A. Birdsey, Michael G. Ryan
2015, Remote Sensing of Environment (169) 113-127
Many studies and production inventory systems have shown the utility of coupling covariates derived from Light Detection and Ranging (LiDAR) data with forest variables measured on georeferenced inventory plots through regression models. The objective of this study was to propose and assess the use of a Bayesian hierarchical modeling framework...
Stable carbon isotope fractionation during bacterial acetylene fermentation: Potential for life detection in hydrocarbon-rich volatiles of icy planet(oid)s
Laurence Miller, Shaun Baesman, Ron Oremland
2015, Astrobiology (15) 977-986
We report the first study of stable carbon isotope fractionation during microbial fermentation of acetylene (C2H2) in sediments, sediment enrichments, and bacterial cultures. Kinetic isotope effects (KIEs) averaged 3.7 ± 0.5‰ for slurries prepared with sediment collected at an intertidal mudflat in San Francisco Bay and 2.7 ± 0.2‰ for a pure culture of Pelobacter sp....
Global climate simulations at 3000-year intervals for the last 21 000 years with the GENMOM coupled atmosphere–ocean model
Jay R. Alder, Steven W. Hostetler
2015, Climate of the Past (11) 449-471
We apply GENMOM, a coupled atmosphere–ocean climate model, to simulate eight equilibrium time slices at 3000-year intervals for the past 21 000 years forced by changes in Earth–Sun geometry, atmospheric greenhouse gases (GHGs), continental ice sheets, and sea level. Simulated global cooling during the Last Glacial Maximum (LGM) is 3.8...
Fire activity as a function of fire–weather seasonal severity and antecedent climate across spatial scales in southern Europe and Pacific western USA
Itziar R. Urbieta, Gonzalo Zavala, Joaquin Bedia, Jose M. Gutierrez, Jesus San Miguel-Ayanz, Andrea Camia, Jon E. Keeley, Jose M. Moreno
2015, Environmental Research Letters (10)
Climate has a strong influence on fire activity, varying across time and space. We analyzed the relationships between fire–weather conditions during the main fire season and antecedent water-balance conditions and fires in two Mediterranean-type regions with contrasted management histories: five southern countries of the European Union (EUMED)(all fires); the Pacific...
Accuracy assessment of NOAA gridded daily reference evapotranspiration for the Texas High Plains
Jerry Moorhead, Prasanna H. Gowda, Michael Hobbins, Gabriel B. Senay, George Paul, Thomas Marek, Dana Porter
2015, Journal of the American Water Resources Association (51) 1262-1271
The National Oceanic and Atmospheric Administration (NOAA) provides daily reference evapotranspiration (ETref) maps for the contiguous United States using climatic data from North American Land Data Assimilation System (NLDAS). This data provides large-scale spatial representation of ETref, which is essential for regional scale water resources management. Data used in the...
Limited role for thermal erosion by turbulent lava in proximal Athabasca Valles, Mars
Vincenzo Cataldo, David A. Williams, Colin M. Dundas, Laszlo P. Keszthelyi
2015, Journal of Geophysical Research E: Planets (120) 1800-1819
The Athabasca Valles flood lava is among the most recent (<50 Ma) and best preserved effusive lava flows on Mars and was probably emplaced turbulently. The Williams et al. (2005) model of thermal erosion by lava has been applied to what we term “proximal Athabasca,” the 75 km long upstream portion of...
Interpretation of hydraulic conductivity in a fractured-rock aquifer over increasingly larger length dimensions
Allen M. Shapiro, Jeffery Ladderud, Richard M. Yager
2015, Hydrogeology Journal (23) 1319-1339
A comparison of the hydraulic conductivity over increasingly larger volumes of crystalline rock was conducted in the Piedmont physiographic region near Bethesda, Maryland, USA. Fluid-injection tests were conducted on intervals of boreholes isolating closely spaced fractures. Single-hole tests were conducted by pumping in open boreholes for approximately 30 min, and an...
Trends and natural variability of North American spring onset as evaluated by a new gridded dataset of spring indices
Toby R. Ault, Mark D. Schwartz, Raul Zurita-Milla, Jake F. Weltzin, Julio L. Betancourt
2015, Journal of Climate (28) 8363-8378
Climate change is expected to modify the timing of seasonal transitions this century, impacting wildlife migrations, ecosystem function, and agricultural activity. Tracking seasonal transitions in a consistent manner across space and through time requires indices that can be used for monitoring and managing biophysical and ecological systems during the coming...
A bootstrap method for estimating uncertainty of water quality trends
Robert M. Hirsch, Stacey A. Archfield, Laura A. DeCicco
2015, Environmental Modelling and Software (73) 148-166
Estimation of the direction and magnitude of trends in surface water quality remains a problem of great scientific and practical interest. The Weighted Regressions on Time, Discharge, and Season (WRTDS) method was recently introduced as an exploratory data analysis tool to provide flexible and robust estimates of water quality trends....
Horseshoe crab spawning activity in Delaware Bay, USA, after harvest reduction: A mixed-model analysis
David R. Smith, Timothy J. Robinson
2015, Estuaries and Coasts (38) 2345-2354
A Delaware Bay, USA, standardized survey of spawning horseshoe crabs, Limulus polyphemus, was carried out in 1999 − 2013 through a citizen science network. Previous trend analyses of the data were at the state (DE or NJ) or bay-wide levels. Here, an alternative mixed-model regression analysis was used to estimate...
Earthquake rupture process recreated from a natural fault surface
Thomas E. Parsons, Diane L. Minasian
2015, Journal of Geophysical Research B: Solid Earth (120) 7852-7862
What exactly happens on the rupture surface as an earthquake nucleates, spreads, and stops? We cannot observe this directly, and models depend on assumptions about physical conditions and geometry at depth. We thus measure a natural fault surface and use its 3D coordinates to construct a replica at 0.1 m...
Geochemistry and origin of metamorphosed mafic rocks from the Lower Paleozoic Moretown and Cram Hill Formations of North-Central Vermont: Delamination magmatism in the western New England appalachians
Raymond Coish, Jonathan Kim, Evan Twelker, Scott P. Zolkos, Gregory J. Walsh
2015, American Journal of Science (315) 809-845
The Moretown Formation, exposed as a north-trending unit that extends from northern Vermont to Connecticut, is located along a critical Appalachian litho-tectonic zone between the paleomargin of Laurentia and accreted oceanic terranes. Remnants of magmatic activity, in part preserved as metamorphosed mafic rocks in the Moretown Formation and the overlying...
Density of river otters (Lontra canadensis) in relation to energy development in the Green River Basin, Wyoming
B.L. Godwin, S.E. Albeke, H.L. Bergman, Annika W. Walters, M. Ben-David
2015, Science of the Total Environment (532) 780-790
Exploration and extraction of oil and natural gas have increased in recent years and are expected to expand in the future. Reduction in water quality from energy extraction may negatively affect water supply for agriculture and urban use within catchments as well as down river. We used non-invasive genetic techniques...
Developing a workflow to identify inconsistencies in volunteered geographic information: a phenological case study
Hamed Mehdipoor, Raul Zurita-Milla, Alyssa Rosemartin, Katharine L. Gerst, Jake F. Weltzin
2015, PLoS ONE (10)
Recent improvements in online information communication and mobile location-aware technologies have led to the production of large volumes of volunteered geographic information. Widespread, large-scale efforts by volunteers to collect data can inform and drive scientific advances in diverse fields, including ecology and climatology. Traditional workflows to check the quality of...
Niche divergence builds the case for ecological speciation in skinks of the Plestiodon skiltonianus species complex
Guinevere O.U. Wogan, Jonathan Q. Richmond
2015, Ecology and Evolution (5) 4683-4695
Adaptation to different thermal environments has the potential to cause evolutionary changes that are sufficient to drive ecological speciation. Here, we examine whether climate-based niche divergence in lizards of the Plestiodon skiltonianus species complex is consistent with the outcomes of such a process. Previous work on this group shows that...
