The spring migration of adult North American Ospreys
Mark S. Martell, Richard O. Bierregaard Jr., Brian E. Washburn, John E. Elliott, Charles J. Henny, Robert S. Kennedy, Iain MacLeod
2014, Journal of Raptor Research (48) 309-324
Most North American Ospreys (Pandion haliaetus) are migratory, breeding in northern latitudes and migrating long distances to and from their wintering grounds in the tropics. Although fall migration patterns of North American Ospreys have been described and studied, very little has been published about the spring migration of these birds....
Energy demands for maintenance, growth, pregnancy, and lactation of female Pacific walruses (Odobenus rosmarus divergens)
Shawn R. Noren, Mark S. Udevitz, Chadwick V. Jay
2014, Physiological and Biochemical Zoology (87) 837-854
Decreases in sea ice have altered habitat use and activity patterns of female Pacific walruses Odobenus rosmarus divergens and could affect their energetic demands, reproductive success, and population status. However, a lack of physiological data from walruses has hampered efforts to develop the bioenergetics models required for fully understanding potential...
MTpy: A Python toolbox for magnetotellurics
Lars Krieger, Jared R. Peacock
2014, Computers & Geosciences (72) 167-175
We present the software package MTpy that allows handling, processing, and imaging of magnetotelluric (MT) data sets. Written in Python, the code is open source, containing sub-packages and modules for various tasks within the standard MT data processing and handling scheme. Besides the independent definition of classes and functions, MTpy provides wrappers and...
Influence of nonnative and native ungulate biomass and seasonal precipitation on vegetation production in a Great Basin ecosystem
Linda Zeigenfuss, Kathryn A. Schoenecker, Jason I. Ransom, Drew A. Ignizio, Tracy Mask
2014, Western North American Naturalist (74) 286-298
The negative effects of equid grazers in semiarid ecosystems of the American West have been considered disproportionate to the influence of native ungulates in these systems because of equids' large body size, hoof shape, and short history on the landscape relative to native ungulates. Tools that can analyze the degree...
Identifying hazards associated with lava deltas
Michael P. Poland, Tim R. Orr
2014, Bulletin of Volcanology (76)
Lava deltas, formed where lava enters the ocean and builds a shelf of new land extending from the coastline, represent a significant local hazard, especially on populated ocean island volcanoes. Such structures are unstable and prone to collapse—events that are often accompanied by small explosions that can deposit boulders and...
Efficacy of plastic mesh tubes in reducing herbivory damage by the invasive nutria (Myocastor coypus) in an urban restoration site
Trevor R. Sheffels, Mark D. Systma, Jacoby Carter, Jimmy D. Taylor
2014, Northwest Science (88) 269-279
The restoration of stream corridors is becoming an increasingly important component of urban landscape planning, and the high cost of these projects necessitates the need to understand and address potential ecological obstacles to project success. The nutria(Myocastor coypus) is an invasive, semi-aquatic rodent native to South America that causes detrimental ecological...
A suggestion for computing objective function in model calibration
Yiping Wu, Shuguang Liu
2014, Ecological Informatics (24) 107-111
A parameter-optimization process (model calibration) is usually required for numerical model applications, which involves the use of an objective function to determine the model cost (model-data errors). The sum of square errors (SSR) has been widely adopted as the objective function in various optimization procedures. However, ‘square error’ calculation was...
Understanding the hydrologic sources and sinks in the Nile Basin using multisource climate and remote sensing data sets
Gabriel B. Senay, Naga Manohar Velpuri, Stefanie Bohms, Yonas Demissie, Mekonnen Gebremichael
2014, Water Resources Research (50) 8625-8650
In this study, we integrated satellite-drived precipitation and modeled evapotranspiration data (2000–2012) to describe spatial variability of hydrologic sources and sinks in the Nile Basin. Over 2000–2012 period, 4 out of 11 countries (Ethiopia, Tanzania, Kenya, and Uganda) in the Nile Basin showed a positive water balance while three downstream...
Evaluation of a model framework to estimate soil and soil organic carbon redistribution by water and tillage using 137Cs in two U.S. Midwest agricultural fields
Claudia J. Young, Shuguang Liu, Joseph A. Schumacher, Thomas E. Schumacher, Thomas C. Kaspar, Gregory W. McCarty, Darrell Napton, Dan B. Jaynes
2014, Geoderma (232-234) 437-448
Cultivated lands in the U.S. Midwest have been affected by soil erosion, causing soil organic carbon (SOC) redistribution in the landscape and other environmental and agricultural problems. The importance of SOC redistribution on soil productivity and crop yield, however, is still uncertain. In this study, we used a model framework,...
Estimates of natural salinity and hydrology in a subtropical estuarine ecosystem: implications for Greater Everglades restoration
Frank E. Marshall, G. Lynn Wingard, Patrick A. Pitts
2014, Estuaries and Coasts (37) 1449-1466
Disruption of the natural patterns of freshwater flow into estuarine ecosystems occurred in many locations around the world beginning in the twentieth century. To effectively restore these systems, establishing a pre-alteration perspective allows managers to develop science-based restoration targets for salinity and hydrology. This paper describes a process to develop...
A sub-national scale geospatial analysis of diamond deposit lootability: the case of the Central African Republic
Katherine C. Malpeli, Peter G. Chirico
2014, The Extractive Industries and Society (1) 249-259
The Central African Republic (CAR), a country with rich diamond deposits and a tumultuous political history, experienced a government takeover by the Seleka rebel coalition in 2013. It is within this context that we developed and implemented a geospatial approach for assessing the lootability of high value-to-weight resource deposits, using...
Aquifers of Arkansas: protection, management, and hydrologic and geochemical characteristics of groundwater resources in Arkansas
Timothy M. Kresse, Phillip D. Hays, Katherine R. Merriman, Jonathan A. Gillip, D. Todd Fugitt, Jane L. Spellman, Anna M. Nottmeier, Drew A. Westerman, Joshua M. Blackstock, James L. Battreal
2014, Scientific Investigations Report 2014-5149
Sixteen aquifers in Arkansas that currently serve or have served as sources of water supply are described with respect to existing groundwater protection and management programs, geology, hydrologic characteristics, water use, water levels, deductive analysis, projections of hydrologic conditions, and water quality. State and Federal protection and management programs are...
Status of groundwater levels and storage volume in the Equus Beds aquifer near Wichita, Kansas, 2012 to 2014
Cristi V. Hansen, Joshua A. Whisnant, Jennifer L. Lanning-Rush
2014, Scientific Investigations Report 2014-5185
Development of the Wichita well field in the Equus Beds aquifer in southwest Harvey County and northwest Sedgwick County began in the 1940s to supply water to the city of Wichita. The decline of water levels in the Equus Beds aquifer was noted soon after the development of the Wichita...
Geologic framework for the national assessment of carbon dioxide storage resources: Williston Basin, Central Montana Basins, and Montana Thrust Belt study areas
Marc L. Buursink, Matthew D. Merrill, William H. Craddock, Tina L. Roberts-Ashby, Sean T. Brennan, Madalyn S. Blondes, P.A. Freeman, Steven M. Cahan, Christina A. DeVera, Celeste D. Lohr
Peter D. Warwick, M.D. Corum, editor(s)
2014, Open-File Report 2012-1024-J
The 2007 Energy Independence and Security Act directs the U.S. Geological Survey (USGS) to conduct a national assessment of potential geologic storage resources for carbon dioxide (CO2). The methodology used by the USGS for the national CO2 assessment follows that of previous USGS work. This methodology is non-economic and is...
A geologic and mineral exploration spatial database for the Stillwater Complex, Montana
Michael L. Zientek, Heather L. Parks
2014, Scientific Investigations Report 2014-5183
The Stillwater Complex is a Neoarchean, ultramafic to mafic layered intrusion exposed in the Beartooth Mountains in south-central Montana. This igneous intrusion contains magmatic mineralization that is variably enriched in strategic and critical commodities such as chromium, nickel, and the platinum-group elements. One deposit, the J-M Reef, is the sole...
Groundwater-flow and land-subsidence model of Antelope Valley, California
Adam J. Siade, Tracy Nishikawa, Diane L. Rewis, Peter Martin, Steven P. Phillips
2014, Scientific Investigations Report 2014-5166
Antelope Valley, California, is a topographically closed basin in the western part of the Mojave Desert, about 50 miles northeast of Los Angeles. The Antelope Valley groundwater basin is about 940 square miles and is separated from the northern part of Antelope Valley by faults and low-lying hills. Prior to...
Database for the geologic map of upper Eocene to Holocene volcanic and related rocks in the Cascade Range, Washington
Andrew D. Barron, David W. Ramsey, James G. Smith
2014, Data Series 842
This geospatial database for a geologic map of the Cascades Range in Washington state is one of a series of maps that shows Cascade Range geology by fitting published and unpublished mapping into a province-wide scheme of lithostratigraphic units. Geologic maps of the Eocene to Holocene Cascade Range in California...
Using vertical Fourier transforms to invert potential-field data to magnetization or density models in the presence of topography
Jeffrey Phillips
2014, Conference Paper, Society of Exploration Geophysicists, 2014 Technical Program Expanded Abstracts
A physical property inversion approach based on the use of 3D (or 2D) Fourier transforms to calculate the potential-field within a 3D (or 2D) volume from a known physical property distribution within the volume is described. Topographic surfaces and observations at arbitrary locations are easily accommodated. The limitations of the...
Influence of fuels, weather and the built environment on the exposure of property to wildfire
Trent D. Penman, Luke S. Collins, Alexandra D. Syphard, Jon E. Keeley, Ross A. Bradstock
2014, PLoS ONE (9)
Wildfires can pose a significant risk to people and property. Billions of dollars are spent investing in fire management actions in an attempt to reduce the risk of loss. One of the key areas where money is spent is through fuel treatment – either fuel reduction (prescribed fire) or fuel...
Optimally managing water resources in large river basins for an uncertain future
Edwin A. Roehl Jr., Paul Conrads
2014, Conference Paper, Proceedings of the 2014 South Carolina Water Resources Conference
Managers of large river basins face conflicting needs for water resources such as wildlife habitat, water supply, wastewater assimilative capacity, flood control, hydroelectricity, and recreation. The Savannah River Basin for example, has experienced three major droughts since 2000 that resulted in record low water levels in its reservoirs, impacting local...
Maps and geospatial data for the Shorty’s Island and Myrtle Bend substrate enhancement pilot projects, Kootenai River near Bonners Ferry, Idaho, 2014
Ryan L. Fosness
2014, Data Series 889
The U.S. Geological Survey, in cooperation with the Idaho Department of Fish and Game, conducted a study to characterize the physical habitat occupied by Kootenai River white sturgeon during spawning and early-life phases. The objective was to gain a better understanding of spawning behavior, site selection, and type of habitat...
Groundwater-quality data in the North San Francisco Bay Shallow Aquifer study unit, 2012: results from the California GAMA Program
George L. Bennett V, Miranda S. Fram
2014, Data Series 865
Groundwater quality in the 1,850-square-mile North San Francisco Bay Shallow Aquifer (NSF-SA) study unit was investigated by the U.S. Geological Survey (USGS) from April to August 2012, as part of the California State Water Resources Control Board (SWRCB) Groundwater Ambient Monitoring and Assessment (GAMA) Program’s Priority Basin Project (PBP). The...
Dual-domain mass-transfer parameters from electrical hysteresis: Theory and analytical approach applied to laboratory, synthetic streambed, and groundwater experiments
Martin A. Briggs, Frederick D. Day-Lewis, John B. Ong, Judson W. Harvey, John W. Lane Jr.
2014, Water Resources Research (50) 8281-8299
Models of dual‐domain mass transfer (DDMT) are used to explain anomalous aquifer transport behavior such as the slow release of contamination and solute tracer tailing. Traditional tracer experiments to characterize DDMT are performed at the flow path scale (meters), which inherently incorporates heterogeneous exchange processes; hence, estimated “effective” parameters are...
Lessons from the 1989 Exxon Valdez oil spill: A biological perspective
Brenda E. Ballachey, James L. Bodkin, Daniel Esler, Stanley D. Rice
2014, Book chapter, Impacts of Oil Spill Disasters on Marine Habitats and Fisheries in North America
On March 24, 1989, the tanker vessel Exxon Valdez altered its course to avoid floating ice, and ran aground on Bligh Reef in northeastern Prince William Sound (PWS), Alaska (Figure 1). The tanker was carrying about 53 million gallons of Prudhoe Bay crude, a heavy oil, and an estimated 11...
The potential for sea-level-rise-induced barrier island loss: Insights from the Chandeleur Islands, Louisiana, USA
Laura J. Moore, Kiki Patsch, Jeffrey H. List, S. Jeffress Williams
2014, Marine Geology (355) 244-259
As sea level rises and hurricanes become more intense, barrier islands around the world become increasingly vulnerable to conversion from self-sustaining migrating landforms to submerging or subaqueous sand bodies. To explore the mechanism by which such state changes occur and to assess the factors leading to island disintegration, we develop...
