Effect of sample holding time on bioaccessibility and sediment ecotoxicological assessments
Kara S Huff Hartz, Federico L. Sinche, Samuel A. Nutile, Courtney Y. Fung, Patrick W. Moran, Peter C. Van Metre, Lisa H. Nowell, Marc A. Mills, Michael J Lydy
2018, Environmental Pollution (242) 2078-2087
The ecotoxicological effects of hydrophobic organic compound (HOC) contamination in sediment are often assessed using laboratory exposures of cultured invertebrates to field-collected sediment. The use of a sediment holding time (storage at 4°C) between field sampling and the beginning of the bioassay is common practice, yet the effect of holding time on the...
Modeling morphodynamic development in the Alviso Slough system, South San Francisco Bay, California
Mick Van der Wegen, Johan Reyes, Bruce Jaffe, Amy Foxgrover
2018, Report
Alviso Slough area, South San Francisco Bay, California, is the site of an ongoing effort to restore former salt production ponds to intertidal habitat. As restoration proceeds and the levees surrounding the former salt production ponds are breached, the increase in tidal prism and associated sediment scour in the sloughs...
It matters when you measure it: Using snow-cover Normalised Difference Vegetation Index (NDVI) to isolate post-fire conifer regeneration
Melanie K. Vanderhoof, Todd Hawbaker
2018, International Journal of Wildland Fire (27) 815-830
Landsat Normalised Difference Vegetation Index (NDVI) is commonly used to monitor post-fire green-up; however, most studies do not distinguish new growth of conifer from deciduous or herbaceous species, despite potential consequences for local climate, carbon and wildlife. We found that dual season (growing and snow cover) NDVI...
Adapting management to a changing world: Warm temperatures, dry soil, and interannual variability limit restoration success of a dominant woody shrub in temperate drylands
Robert K. Shriver, Caitlin M. Andrews, David S. Pilliod, Robert Arkle, Justin L. Welty, Matthew J. Germino, Michael C. Duniway, David A. Pyke, John B. Bradford
2018, Global Change Biology (24) 4972-4982
Restoration and rehabilitation of native vegetation in dryland ecosystems, which encompass over 40% of terrestrial ecosystems, is a common challenge that continues to grow as wildfire and biological invasions transform dryland plant communities. The difficulty in part stems from low and variable precipitation, combined with limited understanding about how weather...
Tropical storm-induced landslide potential using combined field monitoring and numerical modeling
Pan Chen, Ning Lu, Giuseppe Formetta, Jonathan W. Godt, Alexandra Wayllace
2018, Journal of Geotechnical and Geoenvironmental Engineering (144) 1-12
When heavy rainfall, such as that associated with tropical storms, falls on steep hillsides, shallow landslides are often one of the damaging consequences. To assess landslide potential from heavy rainfall, a strategy of combined numerical simulation and field monitoring of variably saturated hillslope conditions is developed. To...
Challenges and opportunities developing mathematical models of shared pathogens of domestic and wild animals
Kathryn P. Huyvaert, Robin E. Russell, Kelly A. Patyk, Meggan E. Craft, Paul C. Cross, M. Graeme Garner, Michael K. Martin, Pauline Nol, Daniel P. Walsh
2018, Veterinary Sciences (5)
Diseases that affect both wild and domestic animals can be particularly difficult to prevent, predict, mitigate, and control. Such multi-host diseases can have devastating economic impacts on domestic animal producers and can present significant challenges to wildlife populations, particularly for populations of conservation concern. Few mathematical models exist that capture...
Climate dictates magnitude of asymmetry in soil depth and hillslope gradient
Assaf Inbar, Petter Nyman, Francis K. Rengers, Patrick N. J. Lane, Gary J. Sheridan
2018, Geophysical Research Letters (45) 6514-6522
Hillslope asymmetry is often attributed to differential eco‐hydro‐geomorphic processes resulting from aspect‐related differences in insolation. At midlatitudes, polar facing hillslopes are steeper, wetter, have denser vegetation, and deeper soils than their equatorial facing counterparts. We propose that at regional scales, the magnitude in insolation‐driven hillslope asymmetry is sensitive to variations...
Evaluating flow management as a strategy to recover an endangered sturgeon species in the Upper Missouri River, USA
Susannah O. Erwin, Edward A. Bulliner, Craig J Fischenich, Robert B. Jacobson, Patrick Braaten, Aaron J. DeLonay
2018, River Research and Applications (34) 1254-1266
In the Upper Missouri River, Fort Peck and Garrison Dams limit the length of free‐flowing river available to the endangered pallid sturgeon. These barriers restrict the upstream migration of adults and downstream larval dispersal. A one‐dimensional (1D) modelling framework is currently in use to evaluate reservoir operation alternatives and to...
Geologic, hydrologic, and water-quality data from multiple-well monitoring sites in the Bunker Hill and Yucaipa Groundwater Subbasins, San Bernardino County, California, 1974–2016
Gregory O. Mendez, Robert Anders, Kelly R. McPherson, Wesley R. Danskin
2018, Data Series 1096
In 1974, the U.S. Geological Survey (USGS), in cooperation with the San Bernardino Valley Municipal Water District, initiated a study to assess the regional groundwater resources in the Bunker Hill Subbasin of the Upper Santa Ana Valley Groundwater Basin in San Bernardino County, California. The study area expanded east into...
Using heat as a tracer to determine groundwater seepage in the Indian River Lagoon, Florida, April–November, 2017
Eric D. Swain, Scott T. Prinos
2018, Open-File Report 2018-1151
The U.S. Geological Survey, in cooperation with the St. Johns River Water Management District, conducted a study to examine water fluxes in two small study areas in the Indian River Lagoon. Vertical arrays of temperature sensors were placed at multiple locations in the lagoon bed to measure temperature time series...
Hidden cost of disease in a free‐ranging ungulate: brucellosis reduces mid‐winter pregnancy in elk
Gavin G. Cotterill, Paul C. Cross, Arthur D. Middleton, Jared D. Rogerson, Brandon Scurlock, Johan T. Du Toit
2018, Ecology and Evolution (8) 10733-10742
Demonstrating disease impacts on the vital rates of free‐ranging mammalian hosts typically requires intensive, long‐term study. Evidence for chronic pathogens affecting reproduction but not survival is rare, but has the potential for wide‐ranging effects. Accurately quantifying disease‐associated reductions in fecundity is important for advancing theory, generating accurate predictive models, and...
Flooding tolerance of Sagittaria latifolia and Sagittaria rigida under controlled laboratory conditions
Kevin P. Kenow, Brian R. Gray, James E. Lyons
2018, River Research and Applications (34) 1024-1031
Pool‐scale growing‐season water‐level reductions (drawdowns) have been implemented on the Upper Mississippi River in an effort to improve fish and wildlife habitat. Aquatic vegetation is a key habitat component, with perennial emergent species, such as Sagittaria latifolia and Sagittaria rigida, especially important. River managers have assumed the need for continuous drawdown during the...
Resiliency of biological soil crusts and vascular plants varies among morphogroups with disturbance intensity
Lea A. Condon, David A. Pyke
2018, Plant and Soil (433) 271-287
Background and aimsDisturbance affects the ability of organisms to persist on a site, and disturbance history acts as a filter of community composition. This is true for vascular plants and morphological groups of biocrusts, which respond differently to disturbance. Although functioning arid ecosystems include both...
Expectations of Maurepas Swamp response to a river reintroduction, Louisiana
Ken W. Krauss, Gary P. Shaffer, Richard F. Keim, Jim L. Chambers, William B. Wood, Stephen B. Hartley
2018, Fact Sheet 2018-3072
Mississippi River reintroductions (freshwater diversions) into wetlands previously disconnected from the river have been implemented in southeastern Louisiana as a means to rehabilitate degraded and submerging wetlands. To date, all active Mississippi River reintroductions have targeted marsh habitat. However, a 57 cubic meter per second (2,000 cubic foot per second)...
Interisland genetic structure of two endangered Hawaiian waterbirds: The Hawaiian Coot and Hawaiian Gallinule
Sarah A. Sonsthagen, Robert E. Wilson, Jared G. Underwood
2018, The Condor (120) 863-873
Most of Hawaii's endemic avifauna are species of conservation concern. Some of Hawaii's endangered waterbirds, however, have increased in number as a result of intensive management of wetlands. To inform these conservation efforts, we examined interisland genetic structure and gene flow within 2 Hawaiian endemic waterbirds, the Hawaiian Coot (Fulica...
Probabilistic substrate classification with multispectral acoustic backscatter: A comparison of discriminative and generative models
Daniel D. Buscombe, Paul E. Grams
2018, Geosciences (8) 1-21
We propose a probabilistic graphical model for discriminative substrate characterization, to support geological and biological habitat mapping in aquatic environments. The model, called a fully-connected conditional random field (CRF), is demonstrated using multispectral and monospectral acoustic backscatter from heterogeneous seafloors in Patricia Bay, British Columbia, and Bedford Basin, Nova Scotia....
Late Cretaceous-Cenozoic exhumation of the western Brooks Range, Alaska, revealed from apatite and zircon fission track data
William H. Craddock, Thomas E. Moore, Paul O'Sullivan, Christopher J. Potter, David W. Houseknecht
2018, Tectonics (37) 4714-4751
We report data for 112 apatite and 31 zircon fission track (AFT and ZFT) outcrop sandstone samples along a transect that spans the western Brooks Range. Sampling targeted structures that modify the Middle Jurassic‐Early Cretaceous early Brookian orogen. The AFT samples record latest Cretaceous to Eocene...
Correcting spacecraft jitter in HiRISE images
S.S. Sutton, A.K. Boyd, Randolph L. Kirk, Debbie Cook, Jean Backer, A. Fennema, R. Heyd, A.S. McEwen, S.D. Mirchandani
2018, Book chapter, Planetary remote sensing and mapping
Mechanical oscillations or vibrations on spacecraft, also called pointing jitter, cause geometric distortions and/or smear in high-resolution digital images acquired from orbit. Geometric distortion is especially a problem with pushbroom sensors, such as the High Resolution Imaging Science Experiment (HiRISE) instrument on-board the Mars Reconnaissance Orbiter (MRO). Geometric distortions occur...
Microclimatic gradients provide evidence for a glacial refugium for temperate trees in a sheltered hilly landscape of Northern Italy
Moritz Gubler, Paul D. Henne, Christoph Schworer, Petra Boltshauser-Kaltenrieder, Andre F. Lotter, Stefan Bronnimann, Willy Tinner
2018, Journal of Biogeography (45) 2564-2575
AimRefugia play a key role in conserving biodiversity during periods of unfavourable and highly variable regional climate. However, refugial populations are often small and fragmented, which makes their identification difficult. In this study, we investigate whether an area of complex topography in the southern foreland of...
Effects of an extreme flood event on federally endangered Diamond Darter abundances
Stuart A. Welsh
2018, The American Midland Naturalist (180) 108-118
Extreme flood events can substantially affect riverine systems, modifying instream habitat and influencing fish assemblages and densities. Rare species are especially vulnerable to these disturbance events because of their small population size and often reduced phenotypic heterogeneity. In June 2016 the lower Elk River in West Virginia experienced severe...
Factors affecting gray wolf (Canis lupus) encounter rate with elk (Cervus elaphus) in Yellowstone National Park
Hans Martin, L. David Mech, John Fieberg, Matthew C. Metz, Daniel R. MacNulty, Daniel R. Stahler, Douglas W. Smith
2018, Canadian Journal of Zoology (96) 1032-1042
Despite encounter rates being a key component of kill rate, few studies of large carnivore predation have quantified encounter rates with prey, the factors that influence them, and the relationship between encounter rate and kill rate. The study’s primary motivation was to determine the relationship between prey density and encounter...
River network saturation concept: factors influencing the balance of biogeochemical supply and demand of river networks
W.M. Wollheim, S. Bernal, Douglas A. Burns, J.A. Czuba, C.T. Driscoll, A.T. Hansen, R.T. Hensley, J.D. Hosen, Shreeram Inamdar, S.S. Kaushall, L. E. Koenig, Y. H. Lu, A. Marzadri, P. A. Raymond, D. Scott, R.J. Stewart, P.G. Vidon, E. Wohl
2018, Biogeochemistry (141) 503-521
River networks modify material transfer from land to ocean. Understanding the factors regulating this function for different gaseous, dissolved, and particulate constituents is critical to quantify the local and global effects of climate and land use change. We propose the River Network Saturation (RNS) concept as a generalization of how...
Watershed ‘chemical cocktails’: forming novel elemental combinations in Anthropocene fresh waters
Sujay S. Kaushal, Arthur J. Gold, Susana Bernal, Tammy A. Newcomer Johnson, Kelly Addy, Amy Burgin, Douglas A. Burns, Ashley A. Coble, Eran W. Hood, Yuehan Lu, Paul Mayer, Elizabeth C. Minor, Andrew W. Schroth, Philippe Vidon, Henry F. Wilson, Marguerite A. Xenopolous, Thomas Doody, Joseph G. Galella, Phillip Goodling, Katherine Haviland, Shahan Haq, Barret Wessel, Kelsey L. Wood, Norbert Jaworski, Kenneth T. Belt
2018, Biogeochemistry (141) 281-305
In the Anthropocene, watershed chemical transport is increasingly dominated by novel combinations of elements, which are hydrologically linked together as ‘chemical cocktails.’ Chemical cocktails are novel because human activities greatly enhance elemental concentrations and their probability for biogeochemical interactions and shared transport along hydrologic flowpaths. A new chemical cocktail approach...
Systematic variation in evapotranspiration trends and drivers across the Northeastern United States
Matthew A Vadeboncoeur, Mark B. Green, Heidi Asbjornsen, John L. Campbell, Mary Beth Adams, Elizabeth W. Boyer, Douglas A. Burns, Ivan J Fernandez, Myron J Mitchell, James B. Shanley
2018, Hydrological Processes (32) 3547-3560
The direction and magnitude of responses of evapotranspiration (ET) to climate change are important to understand, as ET represents a major water and energy flux from terrestrial ecosystems, with consequences that feed back to the climate system. We inferred multidecadal trends in water balance in 11 river basins (1940–2012) and...
Comment on “The earliest modern humans outside Africa”
Warren D. Sharp, James B. Paces
2018, Science (362) 1-2
Hershkovitz et al. (Reports, 26 January 2018, p. 456) interpreted the Misliya-1 fossil maxilla as evidence of the earliest known anatomically modern human outside Africa. However, the fossil’s reported age of 177,000 to 194,000 years relies on flawed interpretations of uranium-series data. We contend that those data support a minimum age...
