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Publication Extents

Not all publications have extents, not all extents are completely accurate
On the halophytic nature of mangroves
Ken W. Krauss, Marilyn C. Ball
2013, Trees: Structure and Function (27) 7-11
Scientists have discussed the halophytic nature of intertidal plants for decades, and have generally suggested that inherent differentiation of an obligate halophyte from a facultative halophyte relates strongly to whether the plant can survive in fresh water, and not much else. In this mini-review, we provide additional insight to support...
Local-area-enhanced, 2.5-meter resolution natural-color and color-infrared satellite-image mosaics of the Takhar mineral district in Afghanistan: Chapter Q in Local-area-enhanced, high-resolution natural-color and color-infrared satellite-image mosaics of mineral districts in Afghanistan
Philip A. Davis, Laura E. Cagney
2013, Data Series 709-Q
The U.S. Geological Survey (USGS), in cooperation with the U.S. Department of Defense Task Force for Business and Stability Operations, prepared databases for mineral-resource target areas in Afghanistan. The purpose of the databases is to (1) provide useful data to ground-survey crews for use in performing detailed assessments of the...
Assessment of macroinvertebrate communities in adjacent urban stream basins, Kansas City, Missouri, metropolitan area, 2007 through 2011
Eric D. Christensen, Heather M. Krempa
2013, Scientific Investigations Report 2012-5284
Macroinvertebrates were collected as part of two separate urban water-quality studies from adjacent basins, the Blue River Basin (Kansas City, Missouri), the Little Blue River and Rock Creek Basins (Independence, Missouri), and their tributaries. Consistent collection and processing procedures between the studies allowed for statistical comparisons. Seven Blue River Basin...
Workshop on New Madrid geodesy and the challenges of understanding intraplate earthquakes
Oliver Boyd, Eric Calais, John O. Langbein, Harold Magistrale, Seth Stein, Mark Zoback
2013, Open-File Report 2013-1004
On March 4, 2011, 26 researchers gathered in Norwood, Massachusetts, for a workshop sponsored by the U.S. Geological Survey and FM Global to discuss geodesy in and around the New Madrid seismic zone (NMSZ) and its relation to earthquake hazard. The group addressed the challenge of reconciling current geodetic measurements,...
Analysis of changes in water-level dynamics at selected sites in the Florida Everglades
Paul Conrads, Stephen T. Benedict
2013, Scientific Investigations Report 2012-5286
The historical modification and regulation of the hydrologic patterns in the Florida Everglades have resulted in changes in the ecosystem of South Florida and the Florida Everglades. Since the 1970s, substantial focus has been given to the restoration of the Everglades ecosystem. The U.S. Geological Survey through its Greater Everglades...
Vegetation impoverishment despite greening: a case study from central Senegal
Stefanie M. Herrmann, G. Gray Tappan
2013, Journal of Arid Environments (90) 55-66
Recent remote sensing studies have documented a greening trend in the semi-arid Sahel and Sudan zones of West Africa since the early 1980s, which challenges the mainstream paradigm of irreversible land degradation in this region. What the greening trend means on the ground, however, has not yet been explored. This...
Occurrence and persistence of fungicides in bed sediments and suspended solids from three targeted use areas in the United States
Kelly L. Smalling, Timothy J. Reilly, Mark W. Sandstrom, Kathryn Kuivila
2013, Science of the Total Environment (447) 179-185
To document the environmental occurrence and persistence of fungicides, a robust and sensitive analytical method was used to measure 34 fungicides and an additional 57 current-use pesticides in bed sediments and suspended solids collected from areas of intense fungicide use within three geographic areas across the United States. Sampling sites...
Hydrography change detection: the usefulness of surface channels derived From LiDAR DEMs for updating mapped hydrography
Sandra K. Poppenga, Dean B. Gesch, Bruce B. Worstell
2013, Journal of the American Water Resources Association (49) 371-389
The 1:24,000-scale high-resolution National Hydrography Dataset (NHD) mapped hydrography flow lines require regular updating because land surface conditions that affect surface channel drainage change over time. Historically, NHD flow lines were created by digitizing surface water information from aerial photography and paper maps. Using these same methods to update nationwide...
Defining a data management strategy for USGS Chesapeake Bay studies
Cassandra Ladino
2013, Open-File Report 2013-1005
The mission of U.S. Geological Survey’s (USGS) Chesapeake Bay studies is to provide integrated science for improved understanding and management of the Chesapeake Bay ecosystem. Collective USGS efforts in the Chesapeake Bay watershed began in the 1980s, and by the mid-1990s the USGS adopted the watershed as one of its...
Assessing the risk of nitrogen deposition to natural resources in the Four Corners area
Sasha C. Reed, Jayne Belnap, Lisa Floyd-Hanna, Tim Crews, Jack Herring, Dave Hanna, Mark E. Miller, Michael C. Duniway, Carla M. Roybal
2013, Report
Nitrogen (N) deposition in the western U.S. is on the rise and is already dramatically affecting terrestrial ecosystems. For example, N deposition has repeatedly been shown to lower air and water quality, increase greenhouse gas emissions, alter plant community composition, and significantly modify fire regimes. Accordingly, the effects of N...
Partial least squares for efficient models of fecal indicator bacteria on Great Lakes beaches
Wesley R. Brooks, Michael N. Fienen, Steven R. Corsi
2013, Journal of Environmental Management (114) 470-475
At public beaches, it is now common to mitigate the impact of water-borne pathogens by posting a swimmer's advisory when the concentration of fecal indicator bacteria (FIB) exceeds an action threshold. Since culturing the bacteria delays public notification when dangerous conditions exist, regression models are sometimes used to predict the...
Population genetic structure of rare and endangered plants using molecular markers
Jennifer Raji, Carter T. Atkinson
2013, Technical Report HCSU-036
This study was initiated to assess the levels of genetic diversity and differentiation in the remaining populations of Phyllostegia stachyoides and Melicope zahlbruckneri in Hawai`i Volcanoes National Park and determine the extent of gene flow to identify genetically distinct individuals or groups for conservation purposes....
Seafloor video footage and still-frame grabs from U.S. Geological Survey cruises in Hawaiian nearshore waters
Ann E. Gibbs, Susan A. Cochran, Peter W. Tierney
2013, Data Series 735
Underwater video footage was collected in nearshore waters (<60-meter depth) off the Hawaiian Islands from 2002 to 2011 as part of the U.S. Geological Survey (USGS) Coastal and Marine Geology Program's Pacific Coral Reef Project, to improve seafloor characterization and for the development and ground-truthing of benthic-habitat maps. This report...
New vitrinite reflectance data for the Wind River Basin, Wyoming
Mark J. Pawlewicz, Thomas M. Finn
2013, Open-File Report 2013-1002
The Wind River Basin is a large Laramide (Late Cretaceous through Eocene) structural and sedimentary basin that encompasses about 7,400 square miles in central Wyoming. The basin is bounded by the Washakie Range and Owl Creek and southern Bighorn Mountains on the north, the Casper arch on the east and...
Local-area-enhanced, 2.5-meter resolution natural-color and color-infrared satellite-image mosaics of the South Helmand mineral district in Afghanistan: Chapter O in Local-area-enhanced, high-resolution natural-color and color-infrared satellite-image mosaics of mineral districts in Afghanistan
Philip A. Davis, Laura E. Cagney
2013, Data Series 709-O
The U.S. Geological Survey (USGS), in cooperation with the U.S. Department of Defense Task Force for Business and Stability Operations, prepared databases for mineral-resource target areas in Afghanistan. The purpose of the databases is to (1) provide useful data to ground-survey crews for use in performing detailed assessments of the...
Temporal shifts in top-down vs. bottom-up control of epiphytic algae in a seagrass ecosystem
Matthew A. Whalen, J. Emmett Duffy, James B. Grace
2013, Ecology (94) 510-520
In coastal marine food webs, small invertebrate herbivores (mesograzers) have long been hypothesized to occupy an important position facilitating dominance of habitat-forming macrophytes by grazing competitively superior epiphytic algae. Because of the difficulty of manipulating mesograzers in the field, however, their impacts on community organization have rarely been rigorously documented....
Representing the acquisition and use of energy by individuals in agent-based models of animal populations
Richard M. Sibly, Volker Grimm, Benjamin T. Martin, Alice Johnston, Katarzyna Kulakowska, Christopher J. Topping, Peter Calow, Jacob Nabe-Nielsen, Pernille Thorbek, Donald L. DeAngelis
2013, Methods in Ecology and Evolution (4) 151-161
1. Agent-based models (ABMs) are widely used to predict how populations respond to changing environments. As the availability of food varies in space and time, individuals should have their own energy budgets, but there is no consensus as to how these should be modelled. Here, we use knowledge of physiological...
Trait contributions to fish community assembly emerge from trophicinteractions in an individual-based model
Henrique C. Giacomini, Donald DeAngelis, Joel C. Trexler, Miguel Petrere Jr.
2013, Ecological Modelling (251) 32-43
Community ecology seeks to understand and predict the characteristics of communities that can develop under different environmental conditions, but most theory has been built on analytical models that are limited in the diversity of species traits that can be considered simultaneously. We address that limitation with an individual-based model to...
Deep subsurface drip irrigation using coal-bed sodic water: part II. geochemistry
Carleton R. Bern, George N. Breit, Richard W. Healy, John W. Zupancic
2013, Agricultural Water Management (118) 135-149
Waters with low salinity and high sodium adsorption ratios (SARs) present a challenge to irrigation because they degrade soil structure and infiltration capacity. In the Powder River Basin of Wyoming, such low salinity (electrical conductivity, EC 2.1 mS cm-1) and high-SAR (54) waters are co-produced with coal-bed methane and some...
Deep subsurface drip irrigation using coal-bed sodic water: part I. water and solute movement
Carleton R. Bern, George N. Breit, Richard W. Healy, John W. Zupancic, Richard Hammack
2013, Agricultural Water Management (118) 122-134
Water co-produced with coal-bed methane (CBM) in the semi-arid Powder River Basin of Wyoming and Montana commonly has relatively low salinity and high sodium adsorption ratios that can degrade soil permeability where used for irrigation. Nevertheless, a desire to derive beneficial use from the water and a need to dispose...
Summary of 2012 reconnaissance field studies related to the petroleum geology of the Nenana Basin, interior Alaska
Marwan A. Wartes, Robert J. Gillis, Trystan M. Herriott, Richard G. Stanley, Kenneth P. Helmold, C. Shaun Peterson, Jeffrey A. Benowitz
2013, Alaska Division of Geological & Geophysical Surveys Preliminary Interpretive Report 2013-2
The Alaska Division of Geological & Geophysical Surveys (DGGS) recently initiated a multi-year review of the hydrocarbon potential of frontier sedimentary basins in Alaska (Swenson and others, 2012). In collaboration with the Alaska Division of Oil & Gas and the U.S. Geological Survey we conducted reconnaissance field studies in two...
Modeling plant species distributions under future climates: how fine scale do climate projections need to be?
Janet Franklin, Frank W. Davis, Makihiko Ikegami, Alexandra D. Syphard, Lorraine E. Flint, Alan L. Flint, Lee Hannah
2013, Global Change Biology (19) 473-483
Recent studies suggest that species distribution models (SDMs) based on fine‐scale climate data may provide markedly different estimates of climate‐change impacts than coarse‐scale models. However, these studies disagree in their conclusions of how scale influences projected species distributions. In rugged terrain, coarse‐scale climate grids may not capture topographically controlled climate...
Hydrocarbon-bearing sandstone in the Upper Jurassic Naknek Formation on the south shore of Kamishak Bay
Richard G. Stanley, Trystan M. Herriott, Kenneth P. Helmold, Robert J. Gillis, Paul G. Lillis
2013, Alaska Division of Geological & Geophysical Surveys Preliminary Interpretive Report 2013-1E
The presence of an active petroleum system in Kamishak Bay is demonstrated by an outcrop of hydrocarbon-bearing sandstone in the Upper Jurassic Naknek Formation near the south shore of the bay (fig. 1). The outcrop is about 140 km southwest of Homer on a small, unnamed island near the mouth...
Reconnaissance studies of potential petroleum source rocks in the Middle Jurassic Tuxedni Group near Red Glacier, eastern slope of Iliamna Volcano
Richard G. Stanley, Trystan M. Herriott, David L. LePain, Kenneth P. Helmold, C. Shaun Peterson
2013, Alaska Division of Geological & Geophysical Surveys Preliminary Interpretive Report 2013-1B
Previous geological and organic geochemical studies have concluded that organic-rich marine shale in the Middle Jurassic Tuxedni Group is the principal source rock of oil and associated gas in Cook Inlet (Magoon and Anders, 1992; Magoon, 1994; Lillis and Stanley, 2011; LePain and others, 2012; LePain and others, submitted). During...