Geomorphic response of the Sandy River, Oregon, to removal of Marmot Dam
Jon J. Major, Jim E. O'Connor, Charles J. Podolak, Mackenzie K. Keith, Gordon E. Grant, Kurt R. Spicer, Smokey Pittman, Heather M. Bragg, J. Rose Wallick, Dwight Q. Tanner, Abagail Rhode, Peter R. Wilcock
2012, Professional Paper 1792
The October 2007 breaching of a temporary cofferdam constructed during removal of the 15-meter (m)-tall Marmot Dam on the Sandy River, Oregon, triggered a rapid sequence of fluvial responses as ~730,000 cubic meters (m3) of sand and gravel filling the former reservoir became available to a high-gradient river. Using direct...
Landscape controls on total and methyl Hg in the Upper Hudson River basin, New York, USA
Douglas A. Burns, K. Riva-Murray, P. M. Bradley, G. R. Aiken, M. E. Brigham
2012, Journal of Geophysical Research (117) G01034
Approaches are needed to better predict spatial variation in riverine Hg concentrations across heterogeneous landscapes that include mountains, wetlands, and open waters. We applied multivariate linear regression to determine the landscape factors and chemical variables that best account for the spatial variation of total Hg (THg) and methyl Hg (MeHg)...
Semiparametric bivariate zero-inflated Poisson models with application to studies of abundance for multiple species
Ali Arab, Scott H. Holan, Christopher K. Wikle, Mark L. Wildhaber
2012, Environmetrics (23) 183-196
Ecological studies involving counts of abundance, presence–absence or occupancy rates often produce data having a substantial proportion of zeros. Furthermore, these types of processes are typically multivariate and only adequately described by complex nonlinear relationships involving externally measured covariates. Ignoring these aspects of the data and implementing standard approaches can...
Reconciling estimates of the contemporary North American carbon balance among terrestrial biosphere models, atmospheric inversions, and a new approach for estimating net ecosystem exchange from inventory-based data
Daniel J. Hayes, David P. Turner, Graham Stinson, A. David McGuire, Yaxing Wei, Tristram O. West, Linda S. Heath, Bernardus de Jong, Brian G. McConkey, Richard A. Birdsey, Werner A. Kurz, Andrew R. Jacobson, Deborah N. Huntzinger, Yude Pan, W. Mac Post, Robert B. Cook
2012, Global Change Biology (18) 1282-1299
We develop an approach for estimating net ecosystem exchange (NEE) using inventory-based information over North America (NA) for a recent 7-year period (ca. 2000–2006). The approach notably retains information on the spatial distribution of NEE, or the vertical exchange between land and atmosphere of all non-fossil fuel sources and sinks...
Role of turbulence fluctuations on uncertainties of acoutic Doppler current profiler discharge measurements
Leticia Tarrab, Carlos M. Garcia, Mariano I. Cantero, Kevin Oberg
2012, Water Resources Research (48) W06507
This work presents a systematic analysis quantifying the role of the presence of turbulence fluctuations on uncertainties (random errors) of acoustic Doppler current profiler (ADCP) discharge measurements from moving platforms. Data sets of three-dimensional flow velocities with high temporal and spatial resolution were generated from direct numerical simulation (DNS) of...
Pattern and process of prescribed fires influence effectiveness at reducing wildfire severity in dry coniferous forests
Robert S. Arkle, David S. Pilliod, Justin L. Welty
2012, Forest Ecology and Management (276) 174-184
We examined the effects of three early season (spring) prescribed fires on burn severity patterns of summer wildfires that occurred 1–3 years post-treatment in a mixed conifer forest in central Idaho. Wildfire and prescribed fire burn severities were estimated as the difference in normalized burn ratio (dNBR) using Landsat imagery....
Multiple age components in individual molybdenite grains
John N. Aleinikoff, Robert A. Creaser, Heather Lowers, Charles W. Magee, Richard I. Grauch
2012, Chemical Geology (300-301) 55-60
Re–Os geochronology of fractions composed of unsized, coarse, and fine molybdenite from a pod of unusual monazite–xenotime gneiss within a granulite facies paragneiss, Hudson Highlands, NY, yielded dates of 950.5 ± 2.5, 953.8 ± 2.6, and 941.2 ± 2.6 Ma, respectively. These dates are not recorded by co-existing zircon, monazite,...
Is science in danger of sanctifying the wolf?
L. David Mech
2012, Biological Conservation (150) 143-149
Historically the wolf (Canis lupus) was hated and extirpated from most of the contiguous United States. The federal Endangered Species Act fostered wolf protection and reintroduction which improved the species' image. Wolf populations reached biological recovery in the Northern Rocky Mountains and upper Midwest, and the animal has been delisted...
Use of flow-normalization to evaluate nutrient concentration and flux changes in Lake Champlain tributaries, 1990-2009
Laura Medalie, Robert M. Hirsch, Stacey A. Archfield
2012, Journal of Great Lakes Research (38) 58-67
The U.S. Geological Survey evaluated 20 years of total phosphorus (P) and total nitrogen (N) concentration data for 18 Lake Champlain tributaries using a new statistical method based on weighted regressions to estimate daily concentration and flux histories based on discharge, season, and trend as explanatory variables. The use of...
Supplementing seed banks to rehabilitate disturbed Mojave Desert shrublands: where do all the seeds go?
Lesley A. DeFalco, Todd C. Esque, Melissa B. Nicklas, Jeffrey M. Kane
2012, Restoration Ecology (20) 85-94
Revegetation of degraded arid lands often involves supplementing impoverished seed banks and improving the seedbed, yet these approaches frequently fail. To understand these failures, we tracked the fates of seeds for six shrub species that were broadcast across two contrasting surface disturbances common to the Mojave Desert—sites compacted by concentrated...
Calcium carbonate nucleation in an alkaline lake surface water, Pyramid Lake, Nevada, USA
Michael M. Reddy, Anthony Hoch
2012, Aquatic Geochemistry (18) 95-113
Calcium concentration and calcite supersaturation (Ω) needed for calcium carbonate nucleation and crystal growth in Pyramid Lake (PL) surface water were determined during August of 1997, 2000, and 2001. PL surface water has Ω values of 10-16. Notwithstanding high Ω, calcium carbonate growth did not occur on aragonite single crystals...
Plate interaction in the NE Caribbean subduction zone from continuous GPS observations
Uri S. ten Brink, Alberto M. Lopez-Vegas
2012, Geophysical Research Letters (39)
Kinematic similarities between the Sumatra and Puerto Rico Trenches highlight the potential for a mega-earthquake along the Puerto Rico Trench and the generation of local and trans-Atlantic tsunamis. We used the horizontal components of continuous GPS (cGPS) measurements from 10 sites on NE Caribbean islands to evaluate strain accumulation along...
Studying biodiversity: is a new paradigm really needed?
James D. Nichols, Evan G. Cooch, Jonathan M. Nichols, John R. Sauer
2012, BioScience (62) 497-502
Authors in this journal have recommended a new approach to the conduct of biodiversity science. This data-driven approach requires the organization of large amounts of ecological data, analysis of these data to discover complex patterns, and subsequent development of hypotheses corresponding to detected patterns. This proposed new approach has been...
Distribution and geochemistry of selected trace elements in the Sacramento River near Keswick Reservoir
Ronald C. Antweiler, Howard E. Taylor, Charles N. Alpers
2012, Chemical Geology (298-9) 70-78
The effect of heavy metals from the Iron Mountain Mines (IMM) Superfund site on the upper Sacramento River is examined using data from water and bed sediment samples collected during 1996-97. Relative to surrounding waters, aluminum, cadmium, cobalt, copper, iron, lead, manganese, thallium, zinc and the rare-earth elements (REE) were...
One hundred years of volcano monitoring in Hawaii
James P. Kauahikaua, Michael P. Poland
2012, Eos, Transactions, American Geophysical Union (93) 29-30
In 2012 the Hawaiian Volcano Observatory (HVO), the oldest of five volcano observatories in the United States, is commemorating the 100th anniversary of its founding. HVO's location, on the rim of Kilauea volcano (Figure 1)—one of the most active volcanoes on Earth—has provided an unprecedented opportunity over the past century...
Preliminary checklist of amphibians and reptiles from Baramita, Guyana
R.P. Reynolds, R.D. MacCulloch
2012, Check List (8) 211-214
We provide an initial checklist of the herpetofauna of Baramita, a lowland rainforest site in the Northwest Region of Guyana. Twenty-five amphibian and 28 reptile species were collected during two separate dry-season visits. New country records for two species of snakes are documented, contributing to the knowledge on the incompletely...
Ultraviolet irradiation effects incorporation of nitrate and nitrite nitrogen into aquatic natural organic matter
Kevin A. Thorn, Larry G. Cox
2012, Journal of Environmental Quality (41) 865-881
One of the concerns regarding the safety and efficacy of ultraviolet radiation for treatment of drinking water and wastewater is the fate of nitrate, particularly its photolysis to nitrite. In this study, 15N NMR was used to establish for the first time that UV irradiation effects the incorporation of nitrate...
The role of mangroves in attenuating storm surges
Keqi Zhang, Huiqing Liu, Yuepeng Li, Hongzhou Xu, Jian Shen, Jamie Rhome, J. Smith III
2012, Estuarine, Coastal and Shelf Science (102-3) 11-23
Field observations and numerical simulations indicate that the 6-to-30-km-wide mangrove forest along the Gulf Coast of South Florida effectively attenuated stormsurges from a Category 3 hurricane, Wilma, and protected the inland wetland by reducing an inundation area of 1800 km2 and restricting surge inundation inside the mangrove zone. The surge...
Amphibians and Reptiles from Paramakatoi and Kato, Guyana
Ross D. MacCulloch, Robert P. Reynolds
2012, Check List: Journal of Species Lists and Distributions (8) 207-210
We report the herpetofauna of two neighboring upland locations in west-central Guyana. Twenty amphibian and 24 reptile species were collected. Only 40% of amphibians and 12.5% of reptiles were collected in both locations. This is one of the few collections made at upland (750-800 m) locations in the Guiana Shield.<br...
Hydrologic conditions controlling runoff generation immediately after wildfire
Brian A. Ebel, John A. Moody, Deborah A. Martin
2012, Water Resources Research (48)
We investigated the control of postwildfire runoff by physical and hydraulic properties of soil, hydrologic states, and an ash layer immediately following wildfire. The field site is within the area burned by the 2010 Fourmile Canyon Fire in Colorado, USA. Physical and hydraulic property characterization included ash thickness, particle size...
Population size of snowy plovers breeding in North America
Susan M. Thomas, James E. Lyons, Brad A. Andres, Elise Elliot T-Smith, Eduardo Palacios, John F. Cavitt, J. Andrew Royle, Suzanne D. Fellows, Kendra Maty, William H. Howe, Eric Mellink, Stefani Melvin, Tara Zimmerman
2012, Waterbirds (35) 1-14
Snowy Plovers (Charadrius nivosus) may be one of the rarest shorebirds in North America yet a comprehensive assessment of their abundance and distribution has not been completed. During 2007 and 2008, 557 discrete wetlands were surveyed and nine additional large wetland complexes sampled in México and the USA. From these...
Landsat: A global land-imaging mission
Water Resources Division, U.S. Geological Survey
2012, Fact Sheet 2012-3072
Across four decades since 1972, Landsat satellites have continuously acquired space-based images of the Earth's land surface, coastal shallows, and coral reefs. The Landsat Program, a joint effort of the U.S. Geological Survey (USGS) and the National Aeronautics and Space Administration (NASA), was established to routinely gather land imagery from...
Erosion, storage, and transport of sediment in two subbasins of the Rio Puerco, New Mexico
A. C. Gellis, M.J. Pavich, A.L. Ellwein, S. Aby, I. Clark, M.E. Wieczorek, R. Viger
2012, GSA Bulletin (124) 817-841
Arroyos in the American Southwest proceed through cut-and-fill cycles that operate at centennial to millennial time scales. The geomorphic community has put much effort into understanding the causes of arroyo cutting in the late Quaternary and in the modern record (late 1800s), while little effort has gone into understanding how...
Conodont color alteration (CAI) as an aid to structural interpretation in the Black Pine Mountains, Idaho
Fred J. Smith Jr., Bruce R. Wardlaw
2012, Open-File Report 2012-1100
The Black Pine Mountains, southeastern Cassia County, Idaho, consist of southern and northern blocks separated by a northeast-trending, high-angle fault. Differences in conodont color alteration values distinguish the two blocks. The southern block has significantly higher organic maturation levels than the northern block and is interpreted to have been thrust...
Estimating parameters of hidden Markov models based on marked individuals: use of robust design data
William L. Kendall, Gary C. White, James E. Hines, Catherine A. Langtimm, Jun Yoshizaki
2012, Ecology (93) 913-920
Development and use of multistate mark-recapture models, which provide estimates of parameters of Markov processes in the face of imperfect detection, have become common over the last twenty years. Recently, estimating parameters of hidden Markov models, where the state of an individual can be uncertain even when it is detected,...
