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Page 1378, results 34426 - 34450

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Publication Extents

Not all publications have extents, not all extents are completely accurate
Influence of dissolved organic matter character on mercury incorporation by planktonic organisms: an experimental study using oligotrophic water from Patagonian lakes
Maria C. Dieguez, Claudia P. Queimalinos, Sergio Ribeiro Guevara, Mark C. Marvin-DiPasquale, Carolina Soto Cardenas, Maria A. Arribere
2013, Journal of Environmental Sciences (25) 1980-1991
Ligands present in dissolved organic matter (DOM) form complexes with inorganic divalent mercury (Hg2+) affecting its bioavailability in pelagic food webs. This investigation addresses the influence of a natural gradient of DOM present in Patagonian lakes on the bioaccumulation of Hg2+ (the prevailing mercury species in the water column of...
Analysis of a GRACE global mascon solution for Gulf of Alaska glaciers
Anthony Arendt, Scott Luthcke, Alex Gardner, Shad O’Neel, David Hill, Geir Moholdt, Waleed Abdalati
2013, Journal of Glaciology (59) 913-924
We present a high-resolution Gravity Recovery and Climate Experiment (GRACE) mascon solution for Gulf of Alaska (GOA) glaciers and compare this with in situ glaciological, climate and other remote-sensing observations. Our GRACE solution yields a GOA glacier mass balance of –65 ± 11 Gt a–1 for the period December 2003...
Degree-day accumulation influences annual variability in growth of age-0 walleye
Christopher S. Uphoff, Casey W. Schoenebeck, W. Wyatt Hoback, Keith D. Koupal, Kevin L. Pope
2013, Fisheries Research (147) 394-398
The growth of age-0 fishes influences survival, especially in temperate regions where size-dependent over-winter mortality can be substantial. Additional benefits of earlier maturation and greater fecundity may exist for faster growing individuals. This study correlated prey densities, growing-degree days, water-surface elevation, turbidity, and chlorophyll a with age-0 walleye Sander vitreus...
Runoff-generated debris flows: observations and modeling of surge initiation, magnitude, and frequency
Jason W. Kean, Scott W. McCoy, Gregory E. Tucker, Dennis M. Staley, Jeffrey A. Coe
2013, Journal of Geophysical Research F: Earth Surface (118) 2190-2207
Runoff during intense rainstorms plays a major role in generating debris flows in many alpine areas and burned steeplands. Yet compared to debris flow initiation from shallow landslides, the mechanics by which runoff generates a debris flow are less understood. To better understand debris flow initiation by surface water runoff,...
Complex resistivity signatures of ethanol biodegradation in porous media
Yves Robert Personna, Lee Slater, Dimitrios Ntarlagiannis, Dale D. Werkema, Zoltan Szabo
2013, Journal of Contaminant Hydrology (153) 37-50
Numerous adverse effects are associated with the accidental release of ethanol (EtOH) and its persistence in the subsurface. Geophysical techniques may permit non-invasive, real time monitoring of microbial degradation of hydrocarbon. We performed complex resistivity (CR) measurements in conjunction with geochemical data analysis on three microbial-stimulated and two control columns...
Documenting utility of paddlefish otoliths for quantification of metals using inductively coupled plasma mass spectrometry
James M. Long, James J. Schaffler
2013, Rapid Communications in Mass Spectrometry (27) 2188-2194
RATIONALE The otoliths of the inner ear of fishes record the environment of their surrounding water throughout their life. For paddlefish (Polyodon spathula), otoliths have not been routinely used by scientists since their detriments were outlined in the early 1940s. We sought to determine if paddlefish otoliths were...
The origin of conodonts and of vertebrate mineralized skeletons
Duncan J.E. Murdock, Xi-Ping Dong, John E. Repetski, Federica Marone, Marco Stampanoni, Philip C.J. Donoghue
2013, Nature (502) 546-549
Conodonts are an extinct group of jawless vertebrates whose tooth-like elements are the earliest instance of a mineralized skeleton in the vertebrate lineage, inspiring the ‘inside-out’ hypothesis that teeth evolved independently of the vertebrate dermal skeleton and before the origin of jaws. However, these propositions have been based on evidence...
First records of Nocomis biguttatus (Hornyhead Chub) from West Virginia discovered in museum voucher specimens
Stuart A. Welsh, Daniel A. Cincotta, Wayne C. Starnes
2013, Northeastern Naturalist (20) N19-N22
Specimens of Nocomis biguttatus (Hornyhead Chub) from South Fork Hughes River (Little Kanawha River drainage, WV) were discovered in two museum lots at the North Carolina Museum of Natural Sciences. These accessions, collected in 1960 and 1966, represent an addition to the state fauna and are the first...
Overview of the magnetic signatures of the Palaeoproterozoic Rustenburg Layered Suite, Bushveld Complex, South Africa
Janine Cole, Carol A. Finn, Susan J. Webb
2013, Precambrian Research (236) 193-213
Aeromagnetic data clearly delineate the mafic rocks of the economically significant Bushveld Igneous Complex. This is mainly due to the abundance of magnetite in the Upper Zone of the Rustenburg Layered Suite of the Bushveld, but strongly remanently magnetised rocks in the Main Zone also contribute significantly in places....
Spatial and temporal variation in efficiency of the Moore egg collector
Thomas A. Worthington, Shannon K. Brewer, Nicole Farless
2013, North American Journal of Fisheries Management (33) 1113-1118
The Moore egg collector (MEC) was developed for quantitative and nondestructive capture of semibuoyant fish eggs. Previous studies have indicated that capture efficiency of the MEC was low and the use of one device did not adequately represent the spatial distribution within the water column of egg surrogates (gellan beads)...
Experimental removal of woody vegetation does not increase nesting success or fledgling production in two grassland sparrows (Ammodramus) in Pennsylvania
Jason M. Hill, Duane R. Diefenbach
2013, The Auk (130) 764-773
The influence of vegetation structure on the probability of daily nest survival (DNS) for grassland passerines has received considerable attention. Some correlative studies suggest that the presence of woody vegetation lowers DNS. Over 3 years (2009–2011), we monitored 215 nests of the Grasshopper Sparrow (Ammodramus savannarum) and Henslow's Sparrow (A....
Nature's refineries — Metals and metalloids in arc volcanoes
R.W. Henley, Byron R. Berger
2013, Earth-Science Reviews (125) 146-170
Chemical data for fumaroles and for atmospheric gas and ash plumes from active arc volcanoes provide glimpses of the rates of release of metal and metalloids, such as Tl and Cd, from shallow and mid-crust magmas. Data from copper deposits formed in ancient volcanoes at depths of up to...
The Sunny Point Formation: a new Upper Cretaceous subsurface unit in the Carolina Coastal Plain
Audra E. Balson, Jean Self-Trail, Dennis O. Terry Jr.
2013, Southeastern Geology (50) 1-16
This paper formally defines the Sunny Point Formation, a new Upper Cretaceous subsurface unit confined to the outer Atlantic Coastal Plain of North and South Carolina. Its type section is established in corehole NH-C-1-2001 (Kure Beach) from New Hanover County, North Carolina. The Sunny Point Formation consists of light-olive-gray to...
Links between riparian landcover, instream environment and fish assemblages in headwater streams of south-eastern Brazil
Bruna B. Cruz, Leandro E. Miranda, Mauricio Cetra
2013, Ecology of Freshwater Fish (22) 607-616
We hypothesised and tested a hierarchical organisation model where riparian landcover would influence bank composition and light availability, which in turn would influence instream environments and control fish assemblages. The study was conducted during the dry season in 11 headwater tributaries of the Sorocaba River in the upper Paraná River...
Thermal controls of Yellowstone cutthroat trout and invasive fishes under climate change
Robert K. Al-Chokhachy, Jay R. Alder, Steven W. Hostetler, Robert E. Gresswell, Bradley Shepard
2013, Global Change Biology (19) 3069-3081
We combine large observed data sets and dynamically downscaled climate data to explore historic and future (2050–2069) stream temperature changes over the topographically diverse Greater Yellowstone Ecosystem (elevation range = 824–4017 m). We link future stream temperatures with fish growth models to investigate how changing thermal regimes could influence the future distribution and...
The role of irrigation runoff and winter rainfall on dissolved organic carbon loads in an agricultural watershed
Neung-Hwan Oh, Brian A. Pellerin, Philip Bachand, Peter J. Hernes, Sandra M. Bachand, Noriaki Ohara, M. Levent Kavvas, Brian A. Bergamaschi, William R. Horwath
2013, Agriculture, Ecosystems and Environment 1-10
We investigated the role of land use/land cover and agriculture practices on stream dissolved organic carbon (DOC) dynamics in the Willow Slough watershed (WSW) from 2006 to 2008. The 415 km2watershed in the northern Central Valley, California is covered by 31% of native vegetation and the remaining 69% of agricultural fields...
A GIS and statistical approach to identify variables that control water quality in hydrothermally altered and mineralized watersheds, Silverton, Colorado, USA
Douglas B. Yager, Raymond H. Johnson, Barnaby W. Rockwell, Jonathan S. Caine, Kathleen S. Smith
2013, Environmental Earth Sciences (70) 1057-1082
Hydrothermally altered bedrock in the Silverton mining area, southwest Colorado, USA, contains sulfide minerals that weather to produce acidic and metal-rich leachate that is toxic to aquatic life. This study utilized a geographic information system (GIS) and statistical approach to identify watershed-scale geologic variables in the Silverton area that influence...
Geomorphic and human influence on large-scale coastal change
Cheryl J. Hapke, Meredith G. Kratzmann, Emily A. Himmelstoss
2013, Geomorphology (199) 160-170
An increasing need exists for regional-scale measurements of shoreline change to aid in management and planning decisions over a broad portion of the coast and to inform assessments of coastal vulnerabilities and hazards. A recent dataset of regional shoreline change, covering a large portion of the U.S. East coast...
Center of Excellence for Geospatial Information Science research plan 2013-18
E. Lynn Usery
2013, Open-File Report 2013-1189
The U.S. Geological Survey Center of Excellence for Geospatial Information Science (CEGIS) was created in 2006 and since that time has provided research primarily in support of The National Map. The presentations and publications of the CEGIS researchers document the research accomplishments that include advances in electronic topographic map design,...
Borehole geophysical, fluid, and hydraulic properties within and near the freshwater/saline-water transition zone, San Antonio segment of the Edwards aquifer, south-central Texas, 2010-11
Jonathan V. Thomas, Gregory P. Stanton
2013, Fact Sheet 2013-3078
The freshwater zone of the San Antonio segment of the Edwards aquifer is used by residents of San Antonio and numerous other rapidly growing communities in south-central Texas as their primary water supply source. This freshwater zone is bounded to the south and southeast by a saline-water zone with an...
Effects of a chronic lower range of triclosan exposure to a stream mesocosm community
C.T. Nietch, E.L. Quinlan, J. Lazorchak, C. Impellitteri, D. Raikow, David M. Walters
2013, Environmental Toxicology and Chemistry (32) 2874-2887
Triclosan (5-chloro-2-(2,4-dichlorophenoxy)phenol) is an antimicrobial found in consumer soaps and toothpaste. It is in treated wastewater effluents at low part per billion concentrations, representing a potentially chronic exposure condition for biota inhabiting receiving streams. A naturally colonized benthos was created using flow-through indoor mesocosms. Then the benthic communities were dosed...
A comparison of adaptive sampling designs and binary spatial models: A simulation study using a census of Bromus inermis
Kathryn M. Irvine, Jamie Thornton, Vickie M. Backus, Matthew G. Hohmann, Erik A. Lehnhoff, Bruce D. Maxwell, Kurt Michels, Lisa Rew
2013, Environmetrics (24) 407-417
Commonly in environmental and ecological studies, species distribution data are recorded as presence or absence throughout a spatial domain of interest. Field based studies typically collect observations by sampling a subset of the spatial domain. We consider the effects of six different adaptive and two non-adaptive sampling designs and choice...
Validating predictions from climate envelope models
J. Watling, D. Bucklin, C. Speroterra, L. Brandt, C. Cabal, Stephanie S. Romañach, Frank J. Mazzotti
2013, PLoS ONE (8)
Climate envelope models are a potentially important conservation tool, but their ability to accurately forecast species’ distributional shifts using independent survey data has not been fully evaluated. We created climate envelope models for 12 species of North American breeding birds previously shown to have experienced poleward range shifts. For each...
A comparative assessment of tools for ecosystem services quantification and valuation
Kenneth J. Bagstad, Darius J. Semmens, Sissel Waage, Robert Winthrop
2013, Ecosystem Services (5) 27-39
To enter widespread use, ecosystem service assessments need to be quantifiable, replicable, credible, flexible, and affordable. With recent growth in the field of ecosystem services, a variety of decision-support tools has emerged to support more systematic ecosystem services assessment. Despite the growing complexity of the tool landscape, thorough reviews of...