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Page 757, results 18901 - 18925

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Publication Extents

Not all publications have extents, not all extents are completely accurate
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...
Understanding the captivity effect on invertebrate communities transplanted into an experimental stream laboratory
Travis S. Schmidt, Holly Rogers, Janet L. Miller, Christopher A. Mebane, Laurie S. Balistrieri
2018, Environmental Toxicology and Chemistry (37) 2820-2834
Little is known about how design and testing methodologies affect the macroinvertebrate communities that are held captive in mesocosms. To address this knowledge gap, we conducted a 32‐d test to determine how seeded invertebrate communities changed once removed from the natural stream and introduced to the laboratory. We evaluated larvae...
Timing and genesis of ore formation in the Qarachilar Cu-Mo-Au deposit, Ahar-Arasbaran metallogenic zone, NW Iran: Evidence from geology, fluid inclusions, O–S isotopes and Re–Os geochronology
Hossein Kouhestani, Mir Ali Asghar Mokhtari, Zhaoshan Chang, Holly J. Stein, Craig A. Johnson
2018, Ore Geology Reviews (102) 757-775
In the Qarachilar Cu-Mo-Au deposit of the Ahar–Arasbaran metallogenic zone (AAMZ), northwest Iran, mineralization occurs as three quartz-sulfide veins that cut granodiorite-quartz monzodiorite rocks of the Qaradagh batholith (QDB). Ore formation can be divided into three stages, with chalcopyrite, molybdenite, and gold-bearing pyrite appearing mainly in the first two stages....
A dirty dozen ways to die: Metrics and modifiers of mortality driven by drought and warming for a tree species
David D. Breshears, Charles J. W. Carroll, Miranda D. Redmond, Andreas P. Wion, Craig D. Allen, Neil S. Cobb, Nashelly Meneses, Jason P. Field, Luke A. Wilson, Darin J. Law, Lindsie M. McCabe, Olivia Newell-Bauer
2018, Frontiers in Forests and Global Change (1)
Tree mortality events driven by drought and warmer temperature, often amplified by pests and pathogens, are emerging as one of the predominant climate change impacts on plants. Understanding and predicting widespread tree mortality events in the future is vital as they affect ecosystem goods and services provided by forests and...
Concentrations of nutrients at the water table beneath forage fields receiving seasonal applications of manure, Whatcom County, Washington, autumn 2011–spring 2015
Stephen E. Cox, Andrew R. Spanjer, Raegan L. Huffman, Robert W. Black, Jack E. Barbash, Nichole M. Embertson
2018, Scientific Investigations Report 2018-5124
The U.S. Geological Survey, in cooperation with the Whatcom Conservation District (WCD), collected groundwater-quality data for roughly 3 years (October 2011–May 2015) from near the water table beneath forage fields receiving regular seasonal applications of liquid dairy manure in Whatcom County, Washington. The work was done as part of...
Evidence for geographic variation in life-cycle processes affecting phenology of the Lyme disease vector Ixodes scapularis (Acari: Ixodidae) in the United States
Nicholas H. Ogden, Genevieve Pang, Howard S. Ginsberg, Graham J. Hickling, Russell L. Burke, Lorenza Beati, Jean I. Tsao
2018, Journal of Medical Entomology (55) 1386-1401
The seasonal activity pattern of immature Ixodes scapularis Say (Acari: Ixodidae) varies geographically in the United States, which may affect the efficiency of transmission cycles of pathogens transmitted by this species. To study the factors that determine seasonality, a multiyear study at seven sites across the geographic range of I. scapularis systematically collected questing...
Establishing chronologies for alluvial-fan sequences with analysis of high-resolution topographic data: San Luis Valley, Colorado, USA
Samuel Johnstone, Adam M. Hudson, Sylvia Nicovich, Chester A. Ruleman, Robert M. Sare, Ren A. Thompson
2018, Geosphere (14) 1-18
On active alluvial fans, debris-flow deposits and frequent avulsions produce a rough topographic surface. As is the case in many initially rough landforms produced by catastrophic processes, the topography of alluvial fans is progressively smoothed, producing textural differences useful in establishing relative age criteria for fans. Here, we outline an...
Upstream migration and spawning success of Chinook salmon in a highly developed, seasonally warm river system
William P. Connor, Kenneth F. Tiffan, James A. Chandler, Dennis W. Rondorf, Billy D. Arnsberg, Kelvin C. Anderson
2018, Reviews in Fisheries Science & Aquaculture (27) 1-50
This review summarizes what is known about the influence of water temperature and velocity on the migration and spawning success of an inland population of Chinook salmon Oncorhynchus tshawytscha. Models are then developed and used to illustrate how migration and spawning success might change if temperatures and velocities increase under a...
Molecular systematics of sturgeon nucleocytoplasmic large DNA viruses
Sharon Clouthier, Eric Anderson, Gael Kurath, Rachel Breyta
2018, Molecular Phylogenetics and Evolution (128) 26-37
Namao virus (NV) is a sturgeon nucleocytoplasmic large DNA virus (sNCLDV) that can cause a lethal disease of the integumentary system in lake sturgeon Acipenser fulvescens. As a group, the sNCLDV have not been assigned to any currently recognized taxonomic family of viruses. In this study, a data set of NV...
The complete maternal mitochondrial genome sequences of two imperiled North American freshwater mussels: Alasmidonta heterodon and Alasmidonta varicosa (Bivalvia: Unionoida: Unionidae)
Aaron Aunins, Cheryl L. Morrison, Heather Galbraith, Michael S. Eackles, W. Bane Schill, Tim L. King
2018, Mitochondrial DNA Part B (3) 1124-1126
The freshwater mussels Alasmidonta heterodon and A. varicosa historically inhabited rivers along the North American Atlantic coast from the Carolinas, U.S.A., to New Brunswick, CA. However, many populations have been extirpated, and A. heterodon is now federally listed in the U.S.A. as endangered, and both A. heterodon and A. varicosa are listed as vulnerable on the IUCN Red List. To...
Evaluating inter-rater reliability and statistical power of vegetation measures assessing deer impact
Danielle R. Begley-Miller, Duane R. Diefenbach, Marc E. McDill, Christopher S. Rosenberry, Emily H. Just
2018, Forests (9)
Long-term vegetation monitoring projects are often used to evaluate how plant communities change through time in response to some external influence. Here, we evaluate the efficacy of vegetation monitoring to consistently detect changes in white-tailed deer browsing effects. Specifically, we compared inter-rater reliability (Cohen’s κ and Lin’s concordance correlation coefficient)...
Estimating the probability of movement and partitioning seasonal survival in an amphibian metapopulation
Erin L. Muths, Larissa L. Bailey, Brad A. Lambert, Scott C. Schneider
2018, Ecosphere (9)
Movement of individuals has been described as one of the best studied, but least understood concepts in ecology. The magnitude of movements, routes, and probability of movement have significant application to conservation. Information about movement can inform efforts to model species persistence and is particularly applicable...
Satellite remote sensing estimation of river discharge: Application to the Yukon River Alaska
David M. Bjerklie, Charon M. Birkett, John Jones, Claudia C. Carabajal, Jennifer Rover, John W, Fulton, Pierre-Andre Garambois
2018, Journal of Hydrology (561) 1000-1018
A methodology based on general hydraulic relations for rivers has been developed to estimate the discharge (flow rate) of rivers using satellite remote sensing observations. The estimates of discharge, flow depth, and flow velocity are derived from remotely observed water...