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Watershed morphology of highland and mountain ecoregions in eastern Oklahoma
D. K. Splinter, Daniel C. Dauwalter, R. A. Marston, William Fisher
2011, Professional Geographer (63) 131-143
The fluvial system represents a nested hierarchy that reflects the relationship among different spatial and temporal scales. Within the hierarchy, larger scale variables influence the characteristics of the next lower nested scale. Ecoregions represent one of the largest scales in the fluvial hierarchy and are defined by recurring patterns of...
Vegetation death and rapid loss of surface elevation in two contrasting Mississippi delta salt marshes: The role of sedimentation, autocompaction and sea-level rise
J.W. Day, G.P. Kemp, D.J. Reed, Donald R. Cahoon, R.M. Boumans, J.M. Suhayda, R. Gambrell
2011, Ecological Engineering (37) 229-240
From 1990 to 2004, we carried out a study on accretionary dynamics and wetland loss in salt marshes surrounding two small ponds in the Mississippi delta; Old Oyster Bayou (OB), a sediment-rich area near the mouth of the Atchafalaya River and Bayou Chitigue (BC), a sediment-poor area about 70 km to the east. The OB site was...
Water chemistry and its effects on the physiology and survival of Atlantic salmon Salmo salar smolts
T. Liebich, S. D. McCormick, D. Kircheis, Kevin Johnson, R. Regal, T. Hrabik
2011, Journal of Fish Biology (79) 502-519
The physiological effects of episodic pH fluctuations on Atlantic salmon Salmo salar smolts in eastern Maine, U.S.A., were investigated. During this study, S. salar smolts were exposed to ambient stream‐water chemistry conditions at nine sites in four catchments for 3 and 6 day intervals during the spring S. salar smolt migration period. Plasma chloride, plasma glucose,...
Derivation of S and Pb in phanerozoic intrusion-related metal deposits from neoproterozoic sedimentary pyrite, Great Basin, United States
Peter G. Vikre, S.R. Poulson, Alan E. Koenig
2011, Economic Geology (106) 883-912
The thick (≤8 km), regionally extensive section of Neoproterozoic siliciclastic strata (terrigenous detrital succession, TDS) in the central and eastern Great Basin contains sedimentary pyrite characterized by mostly high δ34S values (−11.6 to 40.8‰, >70% exceed 10‰; 51 analyses) derived from reduction of seawater sulfate, and by markedly radiogenic Pb isotopes...
Wintering bird response to fall mowing of herbaceous buffers
P.J. Blank, J.R. Parks, G.P. Dively
2011, Wilson Journal of Ornithology (123) 59-64
Herbaceous buffers are strips of herbaceous vegetation planted between working agricultural land and streams or wetlands. Mowing is a common maintenance practice to control woody plants and noxious weeds in herbaceous buffers. Buffers enrolled in Maryland's Conservation Reserve Enhancement Program (CREP) cannot be mowed during the primary bird nesting season...
Distribution and characterization of in-channel large wood in relation to geomorphic patterns on a low-gradient river
Bertrand Moulin, Edward R. Schenk, Cliff R. Hupp
2011, Earth Surface Processes and Landforms (36) 1137-1151
A 177 river km georeferenced aerial survey of in-channel large wood (LW) on the lower Roanoke River, NC was conducted to determine LW dynamics and distributions on an eastern USA low-gradient large river. Results indicate a system with approximately 75% of the LW available for transport either as detached individual...
Scale-dependent factors affecting North American river otter distribution in the midwest
Mackenzie R. Jeffress, Craig P. Paukert, Joanna B. Whittier, B. K. Sandercock, P. S. Gipson
2011, American Midland Naturalist (166) 177-193
The North American river otter (Lontra canadensis) is recovering from near extirpation throughout much of its range. Although reintroductions, trapping regulations and habitat improvements have led to the reestablishment of river otters in the Midwest, little is known about how their distribution is influenced by local- and landscape-scale habitat....
Conservation and management of crayfishes: Lessons from Pennsylvania
D.A. Lieb, R.W. Bouchard, R.F. Carline, T.R. Nuttall, J.R. Wallace, C.L. Burkholder
2011, Fisheries (36) 489-506
North America's crayfish fauna is diverse, ecologically important, and highly threatened. Unfortunately, up‐to‐date information is scarce, hindering conservation and management efforts. In Pennsylvania and nearby states, recent efforts allowed us to determine the conservation status of several native crayfishes and develop management strategies for those species. Due to rarity and...
Wave climate and trends along the eastern Chukchi Arctic Alaska coast
L. H. Erikson, C. D. Storlazzi, R. E. Jensen
2011, Conference Paper, Solutions to Coastal Disasters 2011 - Proceedings of the 2011 Solutions to Coastal Disasters Conference
Due in large part to the difficulty of obtaining measurements in the Arctic, little is known about the wave climate along the coast of Arctic Alaska. In this study, numerical model simulations encompassing 40 years of wave hind-casts were used to assess mean and extreme wave conditions. Results indicate that...
Age, composition, and areal distribution of the Pliocene Lawlor Tuff, and three younger Pliocene tuffs, California and Nevada
Andrei M. Sarna-Wojcicki, Alan L. Deino, Robert J. Fleck, Robert J. McLaughlin, David Wagner, Elmira Wan, David B. Wahl, John W. Hillhouse, Michael Perkins
2011, Geosphere (7) 599-628
The Lawlor Tuff is a widespread dacitic tephra layer produced by Plinian eruptions and ash flows derived from the Sonoma Volcanics, a volcanic area north of San Francisco Bay in the central Coast Ranges of California, USA. The younger, chemically similar Huichica tuff, the tuff of Napa, and the...
Changes in monoterpene mixing ratios during summer storms in rural New Hampshire (USA)
Karl B. Haase, C. Jordan, E. Mentis, L. Cottrell, H.R. Mayne, R. Talbot, B.C. Sive
2011, Atmospheric Chemistry and Physics (11) 11465-11476
Monoterpenes are an important class of biogenic hydrocarbons that influence ambient air quality and are a principle source of secondary organic aerosol (SOA). Emitted from vegetation, monoterpenes are a product of photosynthesis and act as a response to a variety of environmental factors. Most parameterizations of monoterpene emissions are based...
Age and tectonic setting of the Mesozoic McCoy Mountains Formation in western Arizona, USA
J.E. Spencer, S.M. Richard, G. E. Gehrels, J.D. Gleason, W.R. Dickinson
2011, Geological Society of America Bulletin (123) 1258-1274
The McCoy Mountains Formation consists of Upper Jurassic to Upper Cretaceous siltstone, sandstone, and conglomerate exposed in an east-west–trending belt in southwestern Arizona and southeastern California. At least three different tectonic settings have been proposed for McCoy deposition, and multiple tectonic settings are likely over the ∼80 m.y. age range...
Location and agricultural practices influence spring use of harvested cornfields by cranes and geese in Nebraska
Michael J. Anteau, Mark H. Sherfy, A.A. Bishop
2011, Journal of Wildlife Management (75) 1004-1011
Millions of ducks, geese, and sandhill cranes (Grus canadensis; hereafter cranes) stop in the Central Platte River Valley (CPRV) of Nebraska to store nutrients for migration and reproduction by consuming corn remaining in fields after harvest. We examined factors that influence use of cornfields by cranes and geese (all mid‐continent...
Seasonal distribution of Gulf of Mexico sturgeon in the pensacola bay system, Florida
M.S. Duncan, B.M. Wrege, Frank M. Parauka, J. Jeffery Isely
2011, Journal of Applied Ichthyology (27) 316-321
Temporal and spatial distributions of Gulf of Mexico (Gulf) sturgeon Acipenser oxyrinchus desotoi were assessed in the Pensacola bay system, Florida, using stationary ultrasonic telemetry. Fifty‐eight Gulf sturgeon were tagged within the Escambia (n = 26), Yellow (n = 8), Blackwater (n = 12) and Choctawhatchee Rivers (n = 12) in June, July, September and October, 2005. Fifty‐four Gulf sturgeon...
Probing magnetic bottom and crustal temperature variations along the Red Sea margin of Egypt
D. Ravat, A. Salem, A.M.S. Abdelaziz, E. Elawadi, P. Morgan
2011, Tectonophysics (510) 337-344
Over 50 magnetic bottom depths derived from spectra of magnetic anomalies in Eastern Egypt along the Red Sea margin show variable magnetic bottoms ranging from 10 to 34 km. The deep magnetic bottoms correspond more closely to the Moho depth in the region, and not the depth of 580 °C, which lies...
Emergence of viral hemorrhagic septicemia virus in the North American Great Lakes region is associated with low viral genetic diversity
T.M. Thompson, W.N. Batts, M. Faisal, P. Bowser, J.W. Casey, K. Phillips, K.A. Garver, J. Winton, Gael Kurath
2011, Diseases of Aquatic Organisms (96) 29-43
Viral hemorrhagic septicemia virus (VHSV) is a fish rhabdovirus that causes disease in a broad range of marine and freshwater hosts. The known geographic range includes the Northern Atlantic and Pacific Oceans, and recently it has invaded the Great Lakes region of North Ame­rica. The goal of this work was...
Surface-water nutrient conditions and sources in the United States Pacific Northwest
D.R. Wise, H.M. Johnson
2011, Journal of the American Water Resources Association (47) 1110-1135
The SPAtially Referenced Regressions On Watershed attributes (SPARROW) model was used to perform an assessment of surface-water nutrient conditions and to identify important nutrient sources in watersheds of the Pacific Northwest region of the United States (U.S.) for the year 2002. Our models included variables representing nutrient sources as well...
Superficial simplicity of the 2010 El Mayorg-Cucapah earthquake of Baja California in Mexico
S. Wei, E. Fielding, S. Leprince, A. Sladen, J.-P. Avouac, D. Helmberger, E. Hauksson, R. Chu, M. Simons, K. Hudnut, T. Herring, R. Briggs
2011, Nature Geoscience (4) 615-618
The geometry of faults is usually thought to be more complicated at the surface than at depth and to control the initiation, propagation and arrest of seismic ruptures<a id="ref-link-section-d18013e479" title="Bouchon, M., Campillo, M. & Cotton, F. Stress field associated with the rupture of the 1992 Landers, California, earthquake and its...
The remarkable occurrence of large rainfall-induced debris flows at two different locations on July 12, 2008, Southern Sierra Nevada, CA, USA
J.V. DeGraff, D.L. Wagner, A.J. Gallegos, M. DeRose, C. Shannon, T. Ellsworth
2011, Landslides (8) 343-353
On July 12, 2008, two convective cells about 155 km apart produced a brief period of intense rainfall triggering large debris flows in the southern Sierra Nevada. The northernmost cell was centered over Oak Creek Canyon, an east-flowing drainage, and its tributaries near Independence, CA, USA. About 5:00 P.M., debris flows...
Connecting the Yakima fold and thrust belt to active faults in the Puget Lowland, Washington
R.J. Blakely, B.L. Sherrod, C.S. Weaver, R.E. Wells, A.C. Rohay, E. A. Barnett, N.E. Knepprath
2011, Journal of Geophysical Research B: Solid Earth (116)
High-resolution aeromagnetic surveys of the Cascade Range and Yakima fold and thrust belt (YFTB), Washington, provide insights on tectonic connections between forearc and back-arc regions of the Cascadia convergent margin. Magnetic surveys were measured at a nominal altitude of 250 m above terrain and along flight lines spaced 400 m...
Early Mesozoic paleogeography and tectonic evolution of the western United States: Insights from detrital zircon U-Pb geochronology, Blue Mountains Province, northeastern Oregon
Todd A. LaMaskin, J.D. Vervoort, R.J. Dorsey, J.E. Wright
2011, Geological Society of America Bulletin (123) 1939-1965
This study assesses early Mesozoic provenance linkages and paleogeographic-tectonic models for the western United States based on new petrographic and detrital zircon data from Triassic and Jurassic sandstones of the "Izee" and Olds Ferry terranes of the Blue Mountains Province, northeastern Oregon. Triassic sediments were likely derived from the Baker...
Revised correlation of Silurian Provincial Series of North America with global and regional chronostratigraphic units and δ13Ccarb chemostratigraphy
Bradley D. Cramer, Carlton E. Brett, Michael J. Melchin, Peep Mannik, Mark A. Kleffner, Patrick I. McLaughlin, David K. Loydell, Axel Munnecke, Lennart Jeppsson, Carlo Corradini, Frank R. Brunton, Matthew R. Saltzman
2011, Lethaia (44) 185-202
Recent revisions to the biostratigraphic and chronostratigraphic assignment of strata from the type area of the Niagaran Provincial Series (a regional chronostratigraphic unit) have demonstrated the need to revise the chronostratigraphic correlation of the Silurian System of North America. Recently, the working group to restudy the base of the Wenlock...
Early growth of Kohala volcano and formation of long Hawaiian rift zones
Peter W. Lipman, Andrew T. Calvert
2011, Geology (39) 659-662
Transitional-composition pillow basalts from the toe of the Hilo Ridge, collected from outcrop by submersible, have yielded the oldest ages known from the Island of Hawaii: 1138 ± 34 to 1159 ± 33 ka. Hilo Ridge has long been interpreted as a submarine rift zone of Mauna Kea, but the...
An occurrence of the protocetid whale "Eocetus" wardii in the middle Eocene Piney Point Formation of Virginia
Robert E. Weems, Lucy E. Edwards, Jason E. Osborne, A.A. Alford
2011, Journal of Paleontology (85) 271-278
Two protocetid whale vertebrae, here referred to “Eocetus” wardii, have been recovered from the riverbed of the Pamunkey River in east-central Virginia. Neither bone was found in situ, but both were found with lumps of lithified matrix cemented to their surfaces. Most of this matrix was removed and processed for...
Episodic soil succession on basaltic lava fields in a cool, dry environment
K.L. Vaughan, P.A. McDaniel, W.M. Phillips
2011, Soil Science Society of America Journal (75) 1462-1470
Holocene- to late Pleistocene-aged lava flows at Craters of the Moon National Monument and Preserve provide an ideal setting to examine the early stages of soil formation under cool, dry conditions. Transects were used to characterize the amount and nature of soil cover on across basaltic lava flows ranging in...