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Page 1583, results 39551 - 39575

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Not all publications have extents, not all extents are completely accurate
Ultraviolet irradiation effects incorporation of nitrate and nitrite nitrogen into aquatic natural organic matter
Kevin A. Thorn, Larry G. Cox
2012, Journal of Environmental Quality (41) 865-881
One of the concerns regarding the safety and efficacy of ultraviolet radiation for treatment of drinking water and wastewater is the fate of nitrate, particularly its photolysis to nitrite. In this study, 15N NMR was used to establish for the first time that UV irradiation effects the incorporation of nitrate...
The role of mangroves in attenuating storm surges
Keqi Zhang, Huiqing Liu, Yuepeng Li, Hongzhou Xu, Jian Shen, Jamie Rhome, J. Smith III
2012, Estuarine, Coastal and Shelf Science (102-3) 11-23
Field observations and numerical simulations indicate that the 6-to-30-km-wide mangrove forest along the Gulf Coast of South Florida effectively attenuated stormsurges from a Category 3 hurricane, Wilma, and protected the inland wetland by reducing an inundation area of 1800 km2 and restricting surge inundation inside the mangrove zone. The surge...
Spawning and nursery habitats of neotropical fish species in the tributaries of a regulated river
Maristela Cavicchioli Makrakis, Patricia S. da Silva, Sergio Makrakis, Ariane F. de Lima, Lucileine de Assumpcao, Salete de Paula, Leandro E. Miranda, Joao Henrique Pinheiro Dias
2012, Book chapter, Larvae: Morphology, biology, and life cycle
This chapter provides information on ontogenetic patterns of neotropical fish species distribution in tributaries (Verde, Pardo, Anhanduí, and Aguapeí rivers) of the Porto Primavera Reservoir, in the heavily dammed Paraná River, Brazil, identifying key spawning and nursery habitats. Samplings were conducted monthly in the main channel of rivers and in...
Salmonid intranuclear microsporidosis
Ronald P. Hedrick, Maureen K. Purcell, Tomofumi Kurobe
2012, Book chapter, AFS blue book 2014: Section 1 - Diagnostic procedures for finfish and shellfish pathogens
Nucleospora salmonis is an intra-nuclear microsporidian parasite in the family Enterocytozoonidae (Docker et al. 1997). Prespore stages of the parasite were first observed among adult and then juvenile Chinook salmon (Oncorhynchus tshawytscha) by Elston et al. (1987) and Morrison et al. (1990), respectively in Washington,...
Global Change and the Function and Distribution of Wetlands
Beth A. Middleton, editor(s)
2012, Book
The Global Change Ecology and Wetlands book series will highlight the latest research from the world leaders in the field of climate change in wetlands. Global Change and the Function and Distribution of Wetlands highlights information of importance to wetland ecologists.  The chapters include syntheses of international studies on the effects of...
Accumulation of impact markers in desert wetlands and implications for the Younger Dryas impact hypothesis
Jeffrey S. Pigati, Claudio Latorre, Jason A. Rech, Julio L. Betancourt, Katherine E. Martinez, James R. Budahn
2012, Proceedings of the National Academy of Sciences of the United States of America (109) 7208-7212
The Younger Dryas impact hypothesis contends that an extraterrestrial object exploded over North America at 12.9 ka, initiating the Younger Dryas cold event, the extinction of many North American megafauna, and the demise of the Clovis archeological culture. Although the exact nature and location of the proposed impact or explosion...
A conceptual model to facilitate amphibian conservation in the northern Great Plains
David M. Mushet, Ned H. Euliss Jr., Craig A. Stockwell
2012, Great Plains Research (22) 45-58
As pressures on agricultural landscapes to meet worldwide resource needs increase, amphibian populations face numerous threats including habitat destruction, chemical contaminants, disease outbreaks, wetland sedimentation, and synergistic effects of these perturbations. To facilitate conservation planning, we developed a conceptual model depicting elements critical for amphibian conservation in the northern Great...
A new species of Lophostoma d'Orbigny, 1836 (Chiroptera: Phyllostomidae) from Panama
Paul M. Velazco, Alfred L. Gardner
2012, Journal of Mammalogy (93) 605-614
We report the discovery of a new species of Lophostoma from Panama, which we name L. kalkoae. This new species resembles L. carrikeri and L. yasuni in possessing a white venter, but is distinguishable from both by external and cranial characteristics. The new species is similar in size to L....
Assessment of undiscovered oil and gas resources of the East Coast Mesozoic basins of the Piedmont, Blue Ridge Thrust Belt, Atlantic Coastal Plain, and New England Provinces, 2011
Robert C. Milici, James L. Coleman Jr., Elisabeth L. Rowan, Troy A. Cook, Ronald R. Charpentier, Mark A. Kirschbaum, Timothy R. Klett, Richard M. Pollastro, Christopher J. Schenk
2012, Fact Sheet 2012-3075
During the early opening of the Atlantic Ocean in the Mesozoic Era, numerous extensional basins formed along the eastern margin of the North American continent from Florida northward to New England and parts of adjacent Canada. The basins extend generally from the offshore Atlantic continental margin westward beneath the Atlantic...
High-resolution geophysical data collected within Red Brook Harbor, Buzzards Bay, Massachusetts, in 2009
Aaron M. Turecek, William W. Danforth, Wayne E. Baldwin, Walter A. Barnhardt
2012, Open-File Report 2010-1091
The U.S. Geological Survey conducted a high-resolution geophysical survey within Red Brook Harbor, Massachusetts, from September 28 through November 17, 2009. Red Brook Harbor is located on the eastern edge of Buzzards Bay, south of the Cape Cod Canal. The survey area was approximately 7 square kilometers, with depths ranging...
Interim results from a study of the behavior of juvenile Chinook salmon at Cougar Reservoir and Dam, Oregon, March--August 2011
John W. Beeman, Hal C. Hansel, Amy C. Hansen, Philip V. Haner, Jamie M. Sprando, Collin D. Smith, Scott D. Evans
2012, Open-File Report 2012-1106
The movements and dam passage of yearling juvenile Chinook salmon implanted with acoustic transmitters and passive integrated transponder tags were studied at Cougar Reservoir and Dam, near Springfield, Oregon. A total of 411 hatchery fish and 26 wild fish were tagged and released between March 7 and May 21, 2011....
Elementary theory of bed-sediment entrainment by debris flows and avalanches
Richard M. Iverson
2012, Journal of Geophysical Research F: Earth Surface (117)
Analyses of mass and momentum exchange between a debris flow or avalanche and an underlying sediment layer aid interpretations and predictions of bed-sediment entrainment rates. A preliminary analysis assesses the behavior of a Coulomb slide block that entrains bed material as it descends a uniform slope. The analysis demonstrates that...
Factors controlling nitrate fluxes in groundwater in agricultural areas
Lixia Liao, Christopher T. Green, Barbara A. Bekins, J.K. Böhlke
2012, Water Resources Research (48)
The impact of agricultural chemicals on groundwater quality depends on the interactions of biogeochemical and hydrologic factors. To identify key processes affecting distribution of agricultural nitrate in groundwater, a parsimonious transport model was applied at 14 sites across the U.S. Simulated vertical profiles of NO3-, N2 from denitrification, O2, Cl-,...
Sonoran Desert ecosystem transformation by a C4 grass without the grass/fire cycle
Aaryn D. Olsson, Julio Betancourt, Mitchel P. McClaran, Stuart E. Marsh
2012, Diversity and Distributions (2012) 10-21
Aim Biological invasions facilitate ecosystem transformation by altering the structure and function, diversity, dominance and disturbance regimes. A classic case is the grass–fire cycle in which grass invasion increases the frequency, scale and/or intensity of wildfires and promotes the continued invasion of invasive grasses. Despite wide acceptance of the...
Simulated effects of host fish distribution on juvenile unionid mussel dispersal in a large river
J.A. Daraio, L.J. Weber, S. J. Zigler, T.J. Newton, J.M. Nestler
2012, River Research and Applications (28) 594-608
Larval mussels (Family Unionidae) are obligate parasites on fish, and after excystment from their host, as juveniles, they are transported with flow. We know relatively little about the mechanisms that affect dispersal and subsequent settlement of juvenile mussels in large rivers. We used a three-dimensional hydrodynamic model of a reach...
Building the United States National Vegetation Classification
S. B. Franklin, D. Faber-Langendoen, M. Jennings, T. Keeler-Wolf, O. Loucks, R. Peet, D. Roberts, A. McKerrow
2012, Annali di Botanica - Coenology and Plant Ecology (2012) 1-9
The Federal Geographic Data Committee (FGDC) Vegetation Subcommittee, the Ecological Society of America Panel on Vegetation Classification, and NatureServe have worked together to develop the United States National Vegetation Classification (USNVC). The current standard was accepted in 2008 and fosters consistency across Federal agencies and non-federal partners for the description...
Spatiotemporal associations between Pacific herring spawn and surf scoter spring migration: evaluating a "silver wave" hypothesis
Erica K. Lok, Daniel Esler, John Y. Takekawa, Susan E.W. De La Cruz, W. Sean Boyd, David R. Nysewander, Joseph R. Evenson, David H. Ward
2012, Marine Ecology Progress Series (457) 139-150
Surf scoters Melanitta perspicillata are sea ducks that aggregate at spawning events of Pacific herring Clupea pallasi and forage on the eggs, which are deposited in abundance during spring at discrete sites. We evaluated whether migrating scoters followed a ‘silver wave’ of resource availability, analogous to the ‘green wave’ of high-quality foraging conditions that...
Hydrocyclonic separation of invasive New Zealand mudsnails from an aquaculture water source
R. Jordan Nielson, Christine M. Moffitt, Barnaby J. Watten
2012, Aquaculture (326-9) 156-162
Invasive New Zealand mudsnails (Potamopyrgus antipodarum, NZMS) have infested freshwater aquaculture facilities in the western United States and disrupted stocking or fish transportation activities because of the risk of transporting NZMS to naive locations. We tested the efficacy of a gravity-fed, hydrocyclonicseparation system to remove NZMS from an aquaculture water...
Spatial ecology of white-tailed deer fawns in the northern Great Plains: implications of loss of conservation reserve program grasslands
Troy W. Grovenburg, Robert W. Klaver, Jonathan A. Jenks
2012, Journal of Wildlife Management (76) 632-644
Few studies have evaluated how wildlife, and white-tailed deer (Odocoileus virginianus) in particular, respond to Conservation Reserve Program (CRP) grasslands. We conducted a 3-year study (2007–2009) to determine the influence of CRP on fawn ecology during a time of declining CRP enrollment. We captured and radiocollared 81 fawn white-tailed deer...
Pre-spawning migration of adult Pacific lamprey, Entosphenus tridentatus, in the Willamette River, Oregon, U.S.A.
Benjamin J. Clemens, Matthew G. Mesa, Robert J. Magie, Douglas A. Young, Carl B. Schreck
2012, Environmental Biology of Fishes (93) 245-254
We describe the migration distances and timing of the adult Pacific lamprey, Entosphenus tridentatus, in the Willamette River Basin (Oregon, U.S.A.). We conducted aerial surveys to track radio-tagged fish upstream of a major waterfall and hydropower complex en route to spawning areas. We detected 24 out of the...
Do predators control prey species abundance? An experimental test with brown treesnakes on Guam
Earl W. Campbell III, Amy A. Yackel Adams, Sarah J. Converse, Thomas H. Fritts, Gordon H. Rodda
2012, Ecology (93) 1194-1203
The effect of predators on the abundance of prey species is a topic of ongoing debate in ecology; the effect of snake predators on their prey has been less debated, as there exists a general consensus that snakes do not negatively influence the abundance of their prey. However, this viewpoint...
Public participation GIS: a method for identifying ecosystems services
Greg Brown, Jessica Montag, Katie Lyon
2012, Society and Natural Resources (25) 633-651
This study evaluated the use of an Internet-based public participation geographic information system (PPGIS) to identify ecosystem services in Grand County, Colorado. Specific research objectives were to examine the distribution of ecosystem services, identify the characteristics of participants in the study, explore potential relationships between ecosystem services and land use...
Conservation implications when the nest predators are known
Christine Ribic, Frank Thompson
2012, Studies in Avian Biology (43) 23-34
Conservation and management of passerines has largely focused on habitat manipulation or restoration because the natural communities on which these birds depend have been destroyed and fragmented. However, productivity is another important aspect of avian conservation, and nest predation can be a large source of nesting mortality for passerines. Recent...
Modelling rating curves using remotely sensed LiDAR data
Marcus Nathanson, Jason W. Kean, Thomas J. Grabs, Jan Seibert, Hjalmar Laudon, Steve W. Lyon
2012, Hydrological Processes (26) 1427-1434
Accurate stream discharge measurements are important for many hydrological studies. In remote locations, however, it is often difficult to obtain stream flow information because of the difficulty in making the discharge measurements necessary to define stage-discharge relationships (rating curves). This study investigates the feasibility of defining rating curves by using...
Rapid microsatellite identification from Illumina paired-end genomic sequencing in two birds and a snake
Todd A. Castoe, Alexander W. Poole, A. P. Jason de Koning, Kenneth L. Jones, Diana F. Tomback, Sara J. Oyler-McCance, Jennifer A. Fike, Stacey L. Lance, Jeffrey W. Streicher, Eric N. Smith, David D. Pollock
2012, PLoS ONE (7)
Identification of microsatellites, or simple sequence repeats (SSRs), can be a time-consuming and costly investment requiring enrichment, cloning, and sequencing of candidate loci. Recently, however, high throughput sequencing (with or without prior enrichment for specific SSR loci) has been utilized to identify SSR loci. The direct "Seq-to-SSR" approach has an...