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VARBOOT: A spatial bootstrap program for semivariogram uncertainty assessment
Eulogio Pardo-Iguzquiza, Ricardo A. Olea
2012, Computers & Geosciences (41) 188-198
In applied geostatistics, the semivariogram is commonly estimated from experimental data, producing an empirical semivariogram for a specified number of discrete lags. In a second stage, a model defined by a few parameters is fitted to the empirical semivariogram. As the experimental data are usually few and sparsely located, there...
Estimating survival rates with time series of standing age‐structure data
Mark S. Udevitz, Peter J. Gogan
2012, Ecology (93) 726-732
It has long been recognized that age‐structure data contain useful information for assessing the status and dynamics of wildlife populations. For example, age‐specific survival rates can be estimated with just a single sample from the age distribution of a stable, stationary population. For a population that is...
Identification of metapopulation dynamics among Northern Goshawks of the Alexander Archipelago, Alaska, and Coastal British Columbia
Sarah A. Sonsthagen, Erica L. McClaren, Frank I. Doyle, K. Titus, George K. Sage, Robert E. Wilson, Judy R. Gust, Sandra L. Talbot
2012, Conservation Genetics (13) 1045-1057
Northern Goshawks occupying the Alexander Archipelago, Alaska, and coastal British Columbia nest primarily in old-growth and mature forest, which results in spatial heterogeneity in the distribution of individuals across the landscape. We used microsatellite and mitochondrial data to infer genetic structure, gene flow, and fluctuations in population demography through evolutionary...
Demographic population model for American shad: will access to additional habitat upstream of dams increase population sizes?
Julianne E. Harris, Joseph E. Hightower
2012, Marine and Coastal Fisheries: Dynamics, Management, and Ecosystem Science (4) 262-283
American shad Alosa sapidissima are in decline in their native range, and modeling possible management scenarios could help guide their restoration. We developed a density-dependent, deterministic, stage-based matrix model to predict the population-level results of transporting American shad to suitable spawning habitat upstream of dams on the Roanoke River, North Carolina and...
Assessing the potential hydrological impact of the Gibe III Dam on Lake Turkana water level using multi-source satellite data
Naga Manohar Velpuri, Gabriel B. Senay
2012, Hydrology and Earth System Sciences Discussions (16) 3561-3578
Lake Turkana, the largest desert lake in the world, is fed by ungauged or poorly gauged river systems. To meet the demand of electricity in the East African region, Ethiopia is currently building the Gibe III hydroelectric dam on the Omo River, which supplies more than 80% of the inflows...
Progressive failure of sheeted rock slopes: the 2009–2010 Rhombus Wall rock falls in Yosemite Valley, California, USA
Greg M. Stock, Stephen J. Martel, Brian D. Collins, Edwin L. Harp
2012, Earth Surface Processes and Landforms (37) 546-561
Progressive rock-fall failures in natural rock slopes are common in many environments, but often elude detailed quantitative documentation and analysis. Here we present high-resolution photography, video, and laser scanning data that document spatial and temporal patterns of a 15-month-long sequence of at least 14 rock falls from the Rhombus Wall,...
Landsat Data Continuity Mission (LDCM) space to ground mission data architecture
Jack L. Nelson, J.A. Ames, J. Williams, R. Patschke, C. Mott, J. Joseph, H. Garon, G. Mah
2012, Conference Paper
The Landsat Data Continuity Mission (LDCM) is a scientific endeavor to extend the longest continuous multi-spectral imaging record of Earth's land surface. The observatory consists of a spacecraft bus integrated with two imaging instruments; the Operational Land Imager (OLI), built by Ball Aerospace & Technologies Corporation in Boulder, Colorado, and...
Using pad‐stripped acausally filtered strong‐motion data
David Boore, Aida Azari Sisi, Sinan Akkar
2012, Bulletin of the Seismological Society of America (102) 751-760
Most strong‐motion data processing involves acausal low‐cut filtering, which requires the addition of sometimes lengthy zero pads to the data. These padded sections are commonly removed by organizations supplying data, but this can lead to incompatibilities in measures of ground motion derived in the usual way from the padded and...
Physical habitat, water quality, and riverine biological assemblages of selected reaches of the Sheyenne River, North Dakota, 2010
Robert F. Lundgren, Kathleen M. Rowland, Matthew J. Lindsay
2012, Scientific Investigations Report 2011-5178
In 2010, data on physical habitat, water quality, and riverine biological assemblages were collected at selected reaches in four locations (Kleven, Sheyenne, Cooperstown, and West Fargo) on the Sheyenne River in east-central North Dakota. Three of the locations (Kleven, Sheyenne, and Cooperstown) are above Baldhill Dam and one location (West...
Methods for noninvasive bathymetric and velocity surveys for impoundment safety--A case study of Herrington Lake at Dix Dam near Burgin, Kentucky
A. Thomas Ruby III
2012, Scientific Investigations Map 3198
The U.S. Geological Survey (USGS) created bathymetric-contour and water-velocity vector maps for portions of Lake Herrington within 600 feet of the face of Dix Dam near Burgin, Kentucky. The mapping was in support of a study of noninvasive acoustic technology for assessing structural integrity of dams, both as a routine...
Simulation of streamflow and the effects of brush management on water yields in the upper Guadalupe River watershed, south-central Texas, 1995-2010
Johnathan R. Bumgarner, Florence E. Thompson
2012, Scientific Investigations Report 2012-5051
The U.S. Geological Survey, in cooperation with the Texas State Soil and Water Conservation Board and the Upper Guadalupe River Authority, developed and calibrated a Soil and Water Assessment Tool watershed model of the upper Guadalupe River watershed in south-central Texas to simulate streamflow and the effects of brush management...
Thermal profiles for selected river reaches of the Methow and Chewuch Rivers, Washington, August 2011
Andrew S. Gendaszek
2012, Data Series 682
Longitudinal profiles of near-streambed and near-surface temperatures were collected for selected reaches of the Methow and Chewuch Rivers, Washington, during August 2011 to facilitate development of a stream temperature model near the confluence of the Methow and Chewuch Rivers. Temperature was measured using a probe with an internal datalogger towed...
Archive of side scan sonar and swath bathymetry data collected during USGS cruise 10CCT03 offshore of the Gulf Islands National Seashore, Mississippi, from East Ship Island, Mississippi, to Dauphin Island, Alabama, April 2010
Nancy T. DeWitt, James G. Flocks, William R. Pfeiffer, James N. Gibson, Dana S. Wiese
2012, Data Series 671
In April of 2010, the U.S. Geological Survey (USGS) conducted a geophysical survey from the east end of East Ship Island, Miss., extending to the middle of Dauphin Island, Ala. (fig. 1). This survey had a dual purpose: (1) to interlink previously conducted nearshore geophysical surveys (shoreline to ~2...
Hydrologic, vegetation, and soil data collected in selected wetlands of the Big River Management area, Rhode Island, from 2008 through 2010
Meredith S. Borenstein, Francis C. Golet, David S. Armstrong, Robert F. Breault, Timothy D. McCobb, Peter K. Weiskel
2012, Data Series 666
The Rhode Island Water Resources Board planned to develop public water-supply wells in the Big River Management Area in Kent County, Rhode Island. Research in the United States and abroad indicates that groundwater withdrawal has the potential to affect wetland hydrology and related processes. In May 2008, the Rhode Island...
Comparison of two methods for estimating base flow in selected reaches of the South Platte River, Colorado
Joseph P. Capesius, L. Rick Arnold
2012, Scientific Investigations Report 2012-5034
The U.S. Geological Survey, in cooperation with the Colorado Water Conservation Board, compared two methods for estimating base flow in three reaches of the South Platte River between Denver and Kersey, Colorado. The two methods compared in this study are the Mass Balance and the Pilot Point methods. Base-flow estimates...
Modification of selected South Carolina bridge-scour envelope curves
Stephen T. Benedict, Andral W. Caldwell
2012, Scientific Investigations Report 2012-5029
Historic scour was investigated at 231 bridges in the Piedmont and Coastal Plain physiographic provinces of South Carolina by the U.S. Geological Survey in cooperation with the South Carolina Department of Transportation. These investigations led to the development of field-derived envelope curves that provided supplementary tools to assess the potential...
Flooded area and plant zonation in isolated wetlands in well fields in the Northern Tampa Bay Region, Florida, following reductions in groundwater-withdrawal rates
Kim H. Haag, William R. Pfeiffer
2012, Scientific Investigations Report 2012-5039
The extent and duration of the flooded area were compared in two reference wetlands and nine wetlands in well fields in the northern Tampa Bay region, Florida, to determine whether reductions in well-field groundwater-withdrawal rates resulted in increases in wetland flooded area. Flooded area, expressed as a percentage of the...
Estimated trichloroethene transformation rates due to naturally occurring biodegradation in a fractured-rock aquifer
Francis H. Chapelle, Pierre J. Lacombe, Paul M. Bradley
2012, Remediation Journal (22) 7-20
Rates of trichloroethene (TCE) mass transformed by naturally occurring biodegradation processes in a fractured rock aquifer underlying a former Naval Air Warfare Center (NAWC) site in West Trenton, New Jersey, were estimated. The methodology included (1) dividing the site into eight elements of equal size and vertically integrating observed concentrations...
Characterizing mercury concentrations and fluxes in a Coastal Plain watershed: Insights from dynamic modeling and data
H.E. Golden, C.D. Knightes, P.A. Conrads, G. M. Davis, T.D. Feaster, C.A. Journey, S.T. Benedict, M. E. Brigham, P. M. Bradley
2012, Journal of Geophysical Research (117)
Mercury (Hg) is one of the leading water quality concerns in surface waters of the United States. Although watershed-scale Hg cycling research has increased in the past two decades, advances in modeling watershed Hg processes in diverse physiographic regions, spatial scales, and land cover types are needed. The goal of...
Integrated geophysical surveys for mapping lati-andesite intrusive bodies, Chino Valley, Arizona
Hesham El-Kaliouby, Ben K. Sternberg, John P. Hoffmann, V.E. Langenheim
2012, Conference Paper, 25th Symposium on the Application of Geophysics to Engineering and Environmental Problems 2012 : (SAGEEP 2012) : Tucson, Arizona, USA, 25-29 March 2012
Three different geophysical methods (magnetic, transient electromagnetic (TEM) and gravity) were used near Chino Valley, Arizona, USA in order to map a suspected lati-andesite intrusive body (plug) previously located by interpretation of aeromagnetic data. The magnetic and TEM surveys provided the best indication of the location and depth of the...
On the reported ionospheric precursor of the 1999 Hector Mine, California earthquake
Jeremy N. Thomas, Jeffrey J. Love, Attila Komjathy, Olga P. Verkhoglyadova, Mark Butala, Nicholas Rivera
2012, Geophysical Research Letters (39)
Using Global Positioning System (GPS) data from sites near the 16 Oct. 1999 Hector Mine, California earthquake, Pulinets et al. (2007) identified anomalous changes in the ionospheric total electron content (TEC) starting one week prior to the earthquake. Pulinets (2007) suggested that precursory phenomena of this type could be useful...
The Cottonwood Lake study area, a long-term wetland ecosystem monitoring site
David M. Mushet, Ned H. Euliss Jr.
2012, Fact Sheet 2012-3040
The Cottonwood Lake study area is one of only three long-term wetland ecosystem monitoring sites in the prairie pothole region of North America; the other two are Orchid Meadows in South Dakota and St. Denis in Saskatchewan. Of the three, Cottonwood Lake has, by far, the longest continuous data-collection record....
Status of groundwater quality in the San Fernando--San Gabriel study unit, 2005--California GAMA Priority Basin Project
Michael Land, Justin T. Kulongoski, Kenneth Belitz
2012, Scientific Investigations Report 2011-5206
Groundwater quality in the approximately 460-square-mile San Fernando--San Gabriel (FG) study unit was investigated as part of the Priority Basin Project of the Groundwater Ambient Monitoring and Assessment (GAMA) Program. The study area is in Los Angeles County and includes Tertiary-Quaternary sedimentary basins situated within the Transverse Ranges of southern...
Deer Flat National Wildlife Refuge: Lake Lowell water based recreation data summary
Rudy M. Schuster
2012, Report
Introduction: Established in 1909, Deer Flat National Wildlife Refuge is one of the oldest refuges in the National Wildlife Refuge System. The Refuge has two units, Lake Lowell and the Snake River Islands. The Lake Lowell Unit is 10,636 acres and includes the almost 9,000-acre Lake Lowell and surrounding lands....