2014 National Park visitor spending effects: economic contributions to local communities, states, and the nation
Catherine Cullinane Thomas, Christopher Huber, Lynne Koontz
2015, Natural Resource Report NPS/NRSS/EQD/NRR—2015/947
The National Park System covers more than 84 million acres and is comprised of more than 401 sites across the Nation. These lands managed by the National Park Service (NPS) serve as recreational destinations for visitors from across the Nation and around the world. On vacations or on day trips,...
Restricted spatial regression in practice: Geostatistical models, confounding, and robustness under model misspecification
Ephraim M. Hanks, Erin M. Schliep, Mevin Hooten, Jennifer A. Hoeting
2015, Environmetrics (26) 243-254
In spatial generalized linear mixed models (SGLMMs), covariates that are spatially smooth are often collinear with spatially smooth random effects. This phenomenon is known as spatial confounding and has been studied primarily in the case where the spatial support of the process being studied is discrete (e.g., areal spatial data)....
Modifications to risk-targeted seismic design maps for subduction and near-fault hazards
Abbie B. Liel, Nico Luco, Meera Raghunandan, C. Champion
Terje Haukaas, editor(s)
2015, Conference Paper, Proceedings of the 12th international conference on applications of statistics and probability in civil engineering (ICASP12)
ASCE 7-10 introduced new seismic design maps that define risk-targeted ground motions such that buildings designed according to these maps will have 1% chance of collapse in 50 years. These maps were developed by iterative risk calculation, wherein a generic building collapse fragility curve is convolved with the U.S. Geological...
Climate change and vulnerability of bull trout (Salvelinus confluentus) in a fire-prone landscape.
Jeffrey A. Falke, Rebecca L. Flitcroft, Jason B. Dunham, Kristina M. McNyset, Paul F. Hessburg, Gordon H. Reeves
2015, Canadian Journal of Fisheries and Aquatic Sciences (72) 304-318
Linked atmospheric and wildfire changes will complicate future management of native coldwater fishes in fire-prone landscapes, and new approaches to management that incorporate uncertainty are needed to address this challenge. We used a Bayesian network (BN) approach to evaluate population vulnerability of...
Paleoseismic evidence for late Holocene tectonic deformation along the Saddle mountain fault zone, Southeastern Olympic Peninsula, Washington
Elizabeth Barnett, Brian L. Sherrod, Jonathan F. Hughes, Harvey M. Kelsey, Jessica L. Czajkowski, Timothy J. Walsh, Trevor A. Contreras, Elizabeth R. Schermer, Robert J. Carson
2015, Bulletin of the Seismological Society of America (105) 38-71
Trench and wetland coring studies show that northeast‐striking strands of the Saddle Mountain fault zone ruptured the ground about 1000 years ago, generating prominent scarps. Three conspicuous subparallel fault scarps can be traced for 15 km on Light Detection and Ranging (LiDAR) imagery, traversing the foothills of the southeast Olympic Mountains:...
Drought monitoring and assessment: Remote sensing and modeling approaches for the Famine Early Warning Systems Network
Gabriel B. Senay, Naga Manohar Velpuri, Stefanie Bohms, Michael Budde, Claudia Young, James Rowland, James Verdin
2015, Book chapter
Drought monitoring is an essential component of drought risk management. It is usually carried out using drought indices/indicators that are continuous functions of rainfall and other hydrometeorological variables. This chapter presents a few examples of how remote sensing and hydrologic modeling techniques are being used to generate a suite of...
High‐resolution trench photomosaics from image‐based modeling: Workflow and error analysis
Nadine G. Reitman, Scott E.K. Bennett, Ryan D. Gold, Richard W. Briggs, Christopher DuRoss
2015, Bulletin of the Seismological Society of America (105) 2354-2366
Photomosaics are commonly used to construct maps of paleoseismic trench exposures, but the conventional process of manually using image‐editing software is time consuming and produces undesirable artifacts and distortions. Herein, we document and evaluate the application of image‐based modeling (IBM) for creating photomosaics and 3D models of paleoseismic trench exposures,...
Sea lamprey mark type, wounding rate, and parasite-host preference and abundance relationships for lake trout and other species in Lake Ontario
Brian F. Lantry, Jean Adams, Gavin Christie, Teodore Schaner, James Bowlby, Michael Keir, Jana Lantry, Paul Sullivan, Daniel Bishop, Ted Treska, Bruce Morrison
2015, Report
We examined how the frequency of attacks by Sea Lamprey on fishes in Lake Ontario varied in response to Sea Lamprey abundance and preferred host abundance (Lake Trout >432mm). For this analysis we assembled seven data sets. Two fishery independent surveys for Lake Trout: US Geological Survey (USGS)/New York State...
An updated conceptual model of Delta Smelt biology: Our evolving understanding of an estuarine fish
Randy Baxter, Larry R. Brown, Gonzalo Castillo, Louise Conrad, Steven D. Culberson, Matthew P. Dekar, Melissa Dekar, Frederick Feyrer, Thaddeus Hunt, Kristopher Jones, Joseph Kirsch, Anke Mueller-Solger, Matthew Nobriga, Steven B. Slater, Ted Sommer, Kelly Souza, Gregg Erickson, Stephanie Fong, Karen Gehrts, Lenny Grimaldo, Bruce Herbold
2015, Technical Report 90
The main purpose of this report is to provide an up-to-date assessment and conceptual model of factors affecting Delta Smelt (Hypomesus transpacificus) throughout its primarily annual life cycle and to demonstrate how this conceptual model can be used for scientific and management purposes. The Delta Smelt is a small estuarine...
Uranium Sequestration During Biostimulated Reduction and In Response to the Return of Oxic Conditions In Shallow Aquifers
Christopher C. Fuller, Kelly J. Johnson, Katherine Akstin, David M. Singer, Steven B. Yabusaki, Yi Fang, M. Fuhrmann
2015, Report
A proposed approach for groundwater remediation of uranium contamination is to generate reducing conditions by stimulating the growth of microbial populations through injection of electron donor compounds into the subsurface. Sufficiently reducing conditions will result in reduction of soluble hexavalent uranium, U(VI), and precipitation of the less soluble +4 oxidation...
Complex interactions between global change drivers influence mountain forest and slpine GHG sequestration and stream chemistry
Jill Baron, Melannie D. Hartman
2015, Conference Paper, Mountain Views
Many mountain ecosystems are experiencing coincident increases in temperature, levels of atmospheric carbon dioxide (CO2) and atmospheric nitrogen (N) deposition. All are important controls on rates of plant growth, soil microbial activity, nutrient cycling, and stream N export. It is difficult for experimental studies to explore ecosystem responses to more than one or two treatments at...
Automated lidar-derived canopy height estimates for the Upper Mississippi River System
Enrika Hlavacek
2015, Thesis
Land cover/land use (LCU) classifications serve as important decision support products for researchers and land managers. The LCU classifications produced by the U.S. Geological Survey’s Upper Midwest Environmental Sciences Center (UMESC) include canopy height estimates that are assigned through manual aerial photography interpretation techniques. In an effort to improve upon...
Validation of the SCEC broadband platform V14.3 simulation methods using pseudo spectral acceleration data
Douglas S. Dreger, Gregory C. Beroza, Steven M. Day, Christine A. Goulet, Thomas H Jordan, Paul A. Spudich, Jonathan P. Stewart
2015, Seismological Research Letters (86) 39-47
This paper summarizes the evaluation of ground motion simulation methods implemented on the SCEC Broadband Platform (BBP), version 14.3 (as of March 2014). A seven-member panel, the authorship of this article, was formed to evaluate those methods for the prediction of pseudo-‐spectral accelerations (PSAs) of ground motion. The panel’s mandate...
Examining the utility of satellite-based wind sheltering estimates for lake hydrodynamic modeling
Jamon Van Den Hoek, Jordan S. Read, Luke A. Winslow, Paul Montesano, Corey D. Markfort
2015, Remote Sensing of Environment (156) 551-560
Satellite-based measurements of vegetation canopy structure have been in common use for the last decade but have never been used to estimate canopy's impact on wind sheltering of individual lakes. Wind sheltering is caused by slower winds in the wake of topography and shoreline obstacles (e.g. forest canopy) and influences...
Tracing historical trends of Hg in the Mississippi River using Hg concentrations and Hg isotopic compositions in a lake sediment core, Lake Whittington, Mississippi, USA
John E. Gray, Peter C. Van Metre, Michael J. Pribil, Arthur J. Horowitz
2015, Chemical Geology (395) 80-87
Concentrations and isotopic compositions of mercury (Hg) in a sediment core collected from Lake Whittington, an oxbow lake on the Lower Mississippi River, were used to evaluate historical sources of Hg in the Mississippi River basin. Sediment Hg concentrations in the Lake Whittington core have a large 10-15 y peak...
Sensitivity of tsunami evacuation modeling to direction and land cover assumptions
Mathew C. Schmidtlein, Nathan J. Wood
2015, Applied Geography (56) 154-163
Although anisotropic least-cost-distance (LCD) modeling is becoming a common tool for estimating pedestrian-evacuation travel times out of tsunami hazard zones, there has been insufficient attention paid to understanding model sensitivity behind the estimates. To support tsunami risk-reduction planning, we explore two aspects of LCD modeling as it applies to pedestrian...
Variably-saturated groundwater modeling for optimizing managed aquifer recharge using trench infiltration
Victor M. Heilweil, Jerome Benoit, Richard W. Healy
2015, Hydrological Processes (29) 310-319
Spreading-basin methods have resulted in more than 130 million cubic meters of recharge to the unconfined Navajo Sandstone of southern Utah in the past decade, but infiltration rates have slowed in recent years because of reduced hydraulic gradients and clogging. Trench infiltration is a promising alternative technique for increasing recharge...
Joint inversion of seismic and magnetotelluric data in the Parkfield Region of California using the normalized cross-gradient constraint
Ninfa L. Bennington, Haijiang Zhang, Cliff Thurber, Paul A. Bedrosian
2015, Pure and Applied Geophysics (172) 1033-1052
We present jointly inverted models of P-wave velocity (Vp) and electrical resistivity for a two-dimensional profile centered on the San Andreas Fault Observatory at Depth (SAFOD). Significant structural similarity between main features of the separately inverted Vp and resistivity models is exploited by carrying out a joint inversion of the...
Zinc isotopic signatures in eight lake sediment cores from across the United States
Anita Thapalia, David Borrok, Peter C. Van Metre, Jennifer T. Wilson
2015, Environmental Science and Technology (49) 132-140
Zinc is an important trace element pollutant in urban environments; however, the extent of Zn contamination and the sources of urban Zn pollution are often unclear. We measured Zn concentrations and isotopes in sediment cores collected from eight lakes or reservoirs across the United States. We paired these data with...
Predicting Brook Trout occurrence in stream reaches throughout their native range in the eastern United States
Jefferson Tyrell DeWeber, Tyler Wagner
2015, Transactions of the American Fisheries Society (144) 11-24
The Brook Trout Salvelinus fontinalis is an important species of conservation concern in the eastern USA. We developed a model to predict Brook Trout population status within individual stream reaches throughout the species’ native range in the eastern USA. We utilized hierarchical logistic regression with Bayesian estimation to predict Brook...
Mycoplasma agassizii in Morafka's desert tortoise (Gopherus morafkai) in Mexico
Kristin H. Berry, Mary B. Brown, Mercy Vaughn, Timothy A. Gowan, Mary Ann Hasskamp, Ma. Cristina Melendez Torres
2015, Journal of Wildlife Diseases (51) 89-100
We conducted health evaluations of 69 wild and 22 captive Morafka's desert tortoises (Gopherus morafkai) in Mexico between 2005 and 2008. The wild tortoises were from 11 sites in the states of Sonora and Sinaloa, and the captive tortoises were from the state-managed Centro Ecológico de Sonora Zoo in Hermosillo...
How much is new information worth? Evaluating the financial benefit of resolving management uncertainty
Sean L. Maxwell, Jonathan R. Rhodes, Michael C. Runge, Hugh P. Possingham, Chooi Fei Ng, Eve McDonald Madden
2015, Journal of Applied Ecology (52) 12-20
Conservation decision-makers face a trade-off between spending limited funds on direct management action, or gaining new information in an attempt to improve management performance in the future. Value-of-information analysis can help to resolve this trade-off by evaluating how much management performance could improve if new information was gained. Value-of-information analysis...
BET surface area distributions in polar stream sediments: Implications for silicate weathering in a cold-arid environment
Kristen R. Marra, Megan E Elwood Madden, Gerilyn S. Soreghan, Brenda L Hall
2015, Applied Geochemistry (52) 31-42
BET surface area values are critical for quantifying the amount of potentially reactive sediments available for chemical weathering and ultimately, prediction of silicate weathering fluxes. BET surface area values of fine-grained (<62.5 μm) sediment from the hyporheic zone of polar glacial streams in the McMurdo Dry Valleys, Antarctica (Wright and...
Evaluating changes in stream fish species richness over a 50-year time-period within a landscape context
Stephen R. Midway, Tyler Wagner, Bryn H. Tracy, Gabriela M. Hogue, Wayne C. Starnes
2015, Environmental Biology of Fishes (98) 1295-1309
Worldwide, streams and rivers are facing a suite of pressures that alter water quality and degrade physical habitat, both of which can lead to changes in the composition and richness of fish populations. These potential changes are of particular importance in the Southeast USA, home to one of the richest...
Pesticide concentrations in frog tissue and wetland habitats in alandscape dominated by agriculture
Kelly L. Smalling, Rebecca Reeves, Erin L. Muths, Mark W. Vandever, William A. Battaglin, Michelle Hladik, Clay L. Pierce
2015, Science of the Total Environment (502) 80-90
Habitat loss and exposure to pesticides are likely primary factors contributing to amphibian decline in agricultural landscapes. Conservation efforts have attempted to restore wetlands lost through landscape modifications to reduce contaminant loads in surface waters and providing quality habitat to wildlife. The benefits of this increased wetland area, perhaps especially...
