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Page 1309, results 32701 - 32725

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Publication Extents

Not all publications have extents, not all extents are completely accurate
Sediment-hosted stratabound copper assessment of the Neoproterozoic Roan Group, central African copperbelt, Katanga Basin, Democratic Republic of the Congo and Zambia
Michael L. Zientek, James D. Bliss, David W. Broughton, Michael Christie, Paul Denning, Timothy S. Hayes, Murray W. Hitzman, John D. Horton, Susan Frost-Killian, Douglas J. Jack, Sharad Master, Heather L. Parks, Cliff D. Taylor, Anna B. Wilson, Niki E. Wintzer, Jon Woodhead
2014, Scientific Investigations Report 2010-5090-T
This study estimates the location, quality, and quantity of undiscovered copper in stratabound deposits within the Neoproterozoic Roan Group of the Katanga Basin in the Democratic Republic of the Congo and Zambia. The study area encompasses the Central African Copperbelt, the greatest sediment-hosted copper-cobalt province in the world, containing 152...
Global research priorities to mitigate plastic pollution impacts on marine wildlife
Amanda C. Vegter, Mario Barletta, Cathy A. Beck, Jose C. Borrero, Harry Burton, Marnie L. Campbell, Monica F. Costa, Marcus Eriksen, Cecilia Eriksson, Andres Estrades, Kirsten V. Gilardi, Britta D. Hardesty, Juliana A. Ivar do Sul, Jennifer L. Lavers, Bojan Lazar, Laurent Lebreton, Wallace J. Nichols, Christine A. Ribic, Peter G. Ryan, Qamar A. Schuyler, Stephen D. A. Smith, Hideshige Takada, Kathy A. Townsend, Colette C. C. Wabnitz, Chris Wilcox, Lindsay C. Young, Mark Hamann
2014, Endangered Species Research (25) 225-247
Marine wildlife faces a growing number of threats across the globe, and the survival of many species and populations will be dependent on conservation action. One threat in particular that has emerged over the last 4 decades is the pollution of oceanic and coastal habitats with plastic debris. The...
Preliminary monitoring protocol for the tidal freshwater wetland restoration herbivory study in national capital parks--east: Appendix B
Cairn Krafft, Jeffrey S. Hatfield
2014, Report, Anacostia Park wetlands and resident Canada goose management plan/ environmental impact statement
Four tidal freshwater wetland restoration projects have been undertaken within Anacostia Park on lands managed by the National Park Service since 1993. Monitoring the impacts of Canada goose (Branta canadensis) herbivory on the wetland vegetation will play a key role in determining the long-term health of these tidal freshwater wetland...
Lesser Scaup
Michael J. Anteau, Jean-Michel DeVink, David N. Koons, Jane E. Austin, Christine M. Custer, Alan D. Afton
2014, Book chapter, The birds of North America online
No abstract available....
Accounting for false-positive acoustic detections of bats using occupancy models
Matthew J. Clement, Thomas J. Rodhouse, Patricia C. Ormsbee, Joseph M. Szewczak, James D. Nichols
2014, Journal of Applied Ecology (51) 1460-1467
1. Acoustic surveys have become a common survey method for bats and other vocal taxa. Previous work shows that bat echolocation may be misidentified, but common analytic methods, such as occupancy models, assume that misidentifications do not occur. Unless rare, such misidentifications could lead to incorrect inferences with significant management...
A geochemical approach to determine sources and movement of saline groundwater in a coastal aquifer
Robert Anders, Gregory O. Mendez, Kiyoto Futa, Wesley R. Danskin
2014, Groundwater (52) 756-768
Geochemical evaluation of the sources and movement of saline groundwater in coastal aquifers can aid in the initial mapping of the subsurface when geological information is unavailable. Chloride concentrations of groundwater in a coastal aquifer near San Diego, California, range from about 57 to 39,400 mg/L. On the basis of...
Effect of bait and gear type on channel catfish catch and turtle bycatch in a reservoir
Evan C. Cartabiano, David R. Stewart, James M. Long
2014, Journal of Freshwater Ecology (30) 407-415
Hoop nets have become the preferred gear choice to sample channel catfish Ictalurus punctatus but the degree of bycatch can be high, especially due to the incidental capture of aquatic turtles. While exclusion and escapement devices have been developed and evaluated, few have examined bait choice as a method to reduce turtle...
Subsurface geometry of the San Andreas-Calaveras fault junction: Influence of serpentinite and the Coast Range Ophiolite
Janet Tilden Watt, David A. Ponce, Russell W. Graymer, Robert C. Jachens, Robert W. Simpson
2014, Tectonics (33) 2025-2044
While an enormous amount of research has been focused on trying to understand the geologic history and neotectonics of the San Andreas-Calaveras fault (SAF-CF) junction, fundamental questions concerning fault geometry and mechanisms for slip transfer through the junction remain. We use potential-field, geologic, geodetic, and seismicity data to investigate the...
Evaluating the effects of land use on headwater wetland amphibian assemblages in coastal Alabama
Diane M. Alix, Christopher J. Anderson, J. Barry Grand, Craig Guyer
2014, Wetlands (34) 917-926
Anthropogenic land use is known to impact aquatic ecosystems in several ways, including increased frequency and intensity of floods, stream channel incision, sedimentation, and loss of microtopography. Amphibians are susceptible to changes in wetland and surrounding habitats. This study evaluated amphibian assemblages of fifteen headwater slope wetlands in coastal Alabama...
Vegetation dynamics after spring and summer fires in red and white pine stands at Voyageurs National Park
Scott A. Weyenberg, Noel B. Pavlovic
2014, Natural Areas Journal (34) 443-458
Conducting dormant season or springtime prescribed fire treatments has become a common practice in many regions of the United States to restore ecosystems to their natural state. Despite the knowledge that historically, fires often occurred during the summer, the application of summer burns has been deterred, in part, by a...
Spatial structuring within a reservoir fish population: implications for management
David R. Stewart, James M. Long, Daniel E. Shoup
2014, Marine and Freshwater Research (66) 202-212
Spatial structuring in reservoir fish populations can exist because of environmental gradients, species-specific behaviour, or even localised fishing effort. The present study investigated whether white crappie exhibited evidence of improved population structure where the northern more productive half of a lake is closed to fishing to provide waterfowl hunting opportunities....
Depth gradients in food-web processes linking habitats in large lakes: Lake Superior as an exemplar ecosystem
Michael E. Sierszen, Thomas R. Hrabik, Jason D. Stockwell, Anne M Cotter, Joel C. Hoffman, Daniel L. Yule
2014, Freshwater Biology (59) 2122-2136
In large lakes around the world, depth-based changes in the abundance and distribution of invertebrate and fish species suggest that there may be concomitant changes in patterns of resource allocation. Using Lake Superior of the Laurentian Great Lakes as an example, we explored this idea through stable isotope analyses of...
Prolonged instability prior to a regime shift
Trisha Spanbauer, Craig R. Allen, David G. Angeler, Tarsha Eason, Sherilyn C. Fritz, Ahjond S. Garmestani, Kirsty L. Nash, Jeffery R. Stone
2014, PLoS ONE (9) 1-7
Regime shifts are generally defined as the point of ‘abrupt’ change in the state of a system. However, a seemingly abrupt transition can be the product of a system reorganization that has been ongoing much longer than is evident in statistical analysis of a single component of the system. Using...
Population-level effects of egg predation on a native planktivore in a large freshwater lake
David B. Bunnell, Justin G. Mychek-Londer, Charles P. Madenjian
2014, Ecology of Freshwater Fish (23) 604-614
Using a 37-year recruitment time series, we uncovered a field pattern revealing a strong, inverse relationship between bloater Coregonus hoyi recruitment success and slimy sculpin Cottus cognatus biomass in Lake Michigan (United States), one of the largest freshwater lakes of the world. Given that slimy sculpins (and deepwater sculpin Myoxocephalus...
Chemical complexity and source of the White River Ash, Alaska and Yukon
S.J. Preece, Robert G. McGimsey, J.A. Westgate, N.J.G. Pearce, W.K. Hartmann, W.T. Perkins
2014, Geosphere (10) 1020-1042
The White River Ash, a prominent stratigraphic marker bed in Alaska (USA) and Yukon (Canada), consists of multiple compositional units belonging to two geochemical groups. The compositional units are characterized using multiple criteria, with combined glass and ilmenite compositions being the best discriminators. Two compositional units compose the northern group...
Assessing the risk persistent drought using climate model simulations and paleoclimate data
Toby R. Ault, Julia E. Cole, Jonathan T. Overpeck, Gregory T. Pederson, David M. Meko
2014, Journal of Climate (27) 7529-7549
Projected changes in global rainfall patterns will likely alter water supplies and ecosystems in semiarid regions during the coming century. Instrumental and paleoclimate data indicate that natural hydroclimate fluctuations tend to be more energetic at low (multidecadal to multicentury) than at high (interannual) frequencies. State-of-the-art global climate models do not...
A computer program for uncertainty analysis integrating regression and Bayesian methods
Dan Lu, Ming Ye, Mary C. Hill, Eileen P. Poeter, Gary Curtis
2014, Environmental Modelling and Software (60) 45-56
This work develops a new functionality in UCODE_2014 to evaluate Bayesian credible intervals using the Markov Chain Monte Carlo (MCMC) method. The MCMC capability in UCODE_2014 is based on the FORTRAN version of the differential evolution adaptive Metropolis (DREAM) algorithm of Vrugt et al. (2009), which estimates the posterior probability density...
Survival of Atlantic salmon Salmo salar smolts through a hydropower complex
D.S. Stich, M.M. Bailey, Joseph D. Zydlewski
2014, Journal of Fish Biology (85) 1074-1096
This study evaluated Atlantic salmon Salmo salar smolt survival through the lower Penobscot River, Maine, U.S.A., and characterized relative differences in proportional use and survival through the main-stem of the river and an alternative migration route, the Stillwater Branch. The work was conducted prior to removal of two main-stem dams...
Palila restoration research, 1996−2012
Paul C. Banko, Chris Farmer, Carter T. Atkinson, Kevin W. Brinck, Richad Camp, Colleen Cole, Raymond Canner, Steve Dougill, Daniel Goltz, Elizabeth Gray, Steven C. Hess, Jennifer Higashino, Susan I. Jarvi, Luanne Johnson, Leona Laniawe, Megan Laut, Linda Miller, Christopher J. Murray, Daniel Nelson, David L. Leonard, Peter Oboyshi, Leanne Patch-Highfill, David D. Pollock, Kalei Rapozo, Marla Schwarzfeld, John Slotterback, Robert M. Stephens
Paul C. Banko, Chris Farmer, editor(s)
2014, Technical Report HCSU-046
The Palila Restoration Project was initiated in 1996 by the U.S. Geological Survey to assist government agencies mitigate the effects of realigning Saddle Road (Highway 200) through Palila Critical Habitat (U.S. Fish and Wildlife Service 1998, Federal Highway Administration 1999). Ecological research on the palila (Loxioides bailleui), an endangered Hawaiian...
Macroevolutionary consequences of profound climate change on niche evolution in marine molluscs over the past three million years
E.E. Saupe, J.R. Hendricks, R.W. Portell, Harry J. Dowsett, A. M. Haywood, S.J. Hunter, B.S. Lieberman
2014, Proceedings of the Royal Society B: Biological Sciences (281)
In order to predict the fate of biodiversity in a rapidly changing world, we must first understand how species adapt to new environmental conditions. The long-term evolutionary dynamics of species' physiological tolerances to differing climatic regimes remain obscure. Here, we unite palaeontological and neontological data to analyse whether species' environmental...
Variable population exposure and distributed travel speeds in least-cost tsunami evacuation modelling
Stuart A. Fraser, Nathan J. Wood, David A. Johnston, Graham S. Leonard, Paul D. Greening, Tiziana Rossetto
2014, Natural Hazards and Earth System Sciences (14) 2975-2991
Evacuation of the population from a tsunami hazard zone is vital to reduce life-loss due to inundation. Geospatial least-cost distance modelling provides one approach to assessing tsunami evacuation potential. Previous models have generally used two static exposure scenarios and fixed travel speeds to represent population movement. Some analyses have assumed...
Distribution, stock composition and timing, and tagging response of wild Chinook Salmon returning to a large, free-flowing river basin
John H. Eiler, Michele Masuda, Ted R. Spencer, Richard J. Driscoll, Carl B. Schreck
2014, Transactions of the American Fisheries Society (143) 1476-1507
Chinook Salmon Oncorhynchus tshawytscha returns to the Yukon River basin have declined dramatically since the late 1990s, and detailed information on the spawning distribution, stock structure, and stock timing is needed to better manage the run and facilitate conservation efforts. A total of 2,860 fish were radio-tagged in the lower basin during...
The destructive 1946 Unimak near-field tsunami: New evidence for a submarine slide source from reprocessed marine geophysical data
Roland E. von Huene, Stephen Kirby, John J. Miller, Peter Dartnell
2014, Geophysical Research Letters (41) 6811-6818
The Mw 8.6 earthquake in 1946 off the Pacific shore of Unimak Island at the end of the Alaska Peninsula generated a far-field tsunami that crossed the Pacific to Antarctica. Its tsunami magnitude, 9.3, is comparable to the 9.1 magnitude of the 2011 Tohoku tsunami. On Unimak Island's Pacific shore,...
Climatic and density influences on recruitment in an irruptive population of Roosevelt elk
Heath D. Starns, Mark A. Ricca, Adam Duarte, Floyd W. Weckerly
2014, Journal of Mammalogy (95) 925-932
Current paradigms of ungulate population ecology recognize that density-dependent and independent mechanisms are not always mutually exclusive. Long-term data sets are necessary to assess the relative strength of each mechanism, especially when populations display irruptive dynamics. Using an 18-year time series of population abundances of Roosevelt elk (Cervus elaphus roosevelti) inhabiting...
Development of intestinal ion-transporting mechanisms during smoltification and seawater acclimation in Atlantic salmon Salmo salar
Henrik Sundh, Tom O. Nilsen, Jenny Lindstrom, Linda Hasselberg-Frank, Sigurd O. Stefansson, Stephen D. McCormick, K. Sundell
2014, Journal of Fish Biology (85) 1227-1252
This study investigated the expression of ion transporters involved in intestinal fluid absorption and presents evidence for developmental changes in abundance and tissue distribution of these transporters during smoltification and seawater (SW) acclimation of Atlantic salmonSalmo salar. Emphasis was placed on Na+, K+-ATPase (NKA) and Na+, K+, Cl− co-transporter (NKCC) isoforms,...