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Page 645, results 16101 - 16125

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Exploring mechanisms underlying sex-specific differences in mortality of Lake Michigan bloaters
D.B. Bunnell, C.P. Madenjian, M.W. Rogers, J.D. Holuszko, L.J. Begnoche
2012, Transactions of the American Fisheries Society (141) 204-214
Sex-specific differences in mortality rates have been observed among freshwater and marine fish taxa, and underlying mechanisms can include sex-specific differences in (1) age at maturity, (2) growth rate, or (3) activity or behavior during the spawning period. We used a long-term (1973–2009) Lake Michigan data set to evaluate whether...
Ocean-atmosphere dynamics during Hurricane Ida and Nor'Ida: An application of the coupled ocean-atmosphere-wave-sediment transport (COAWST) modeling system
Maitane Olabarrieta, John C. Warner, Brandy N. Armstrong, Joseph B. Zambon, Ruoying He
2012, Ocean Modelling (43-44) 112-137
The coupled ocean–atmosphere–wave–sediment transport (COAWST) modeling system was used to investigate atmosphere–ocean–wave interactions in November 2009 during Hurricane Ida and its subsequent evolution to Nor’Ida, which was one of the most costly storm systems of the past two decades. One interesting aspect of this...
Reducing uncertainty about objective functions in adaptive management
Byron K. Williams
2012, Ecological Modelling (225) 61-65
This paper extends the uncertainty framework of adaptive management to include uncertainty about the objectives to be used in guiding decisions. Adaptive decision making typically assumes explicit and agreed-upon objectives for management, but allows for uncertainty as to the structure of the decision process that generates change through time. Yet...
Slab1.0: A three-dimensional model of global subduction zone geometries
Gavin P. Hayes, David J. Wald, Rebecca L. Johnson
2012, Journal of Geophysical Research B: Solid Earth (117)
We describe and present a new model of global subduction zone geometries, called Slab1.0. An extension of previous efforts to constrain the two-dimensional non-planar geometry of subduction zones around the focus of large earthquakes, Slab1.0 describes the detailed, non-planar, three-dimensional geometry of approximately 85% of subduction zones worldwide. While the...
Histologic, immunologic and endocrine biomarkers indicate contaminant effects in fishes of the Ashtabula River
L. R. Iwanowicz, V. S. Blazer, N.P. Hitt, S. D. McCormick, D.S. Devault, C. A. Ottinger
2012, Ecotoxicology (21) 165-182
The use of fish as sentinels of aquatic ecosystem health is a biologically relevant approach to environmental monitoring and assessment. We examined the health of the Ashtabula River using histologic, immunologic, and endocrine biomarkers in brown bullhead (BB; Ameiurus nebulosus) and largemouth bass (Micropterus salmoides) and compared fish collected from...
An investigation of element ratios for assessing suspended-sediment sources in small agricultural basins
K. Juracek
2012, Physical Geography (33) 50-67
Various sediment properties previously have been investigated for the purpose of determining sources of suspended sediment. A remaining research need is an assessment of element ratios for the determination of suspended-sediment sources in different terrestrial environments. In this study, 253 element ratios were assessed to determine which, if any, were...
Surface heat flow and CO2 emissions within the Ohaaki hydrothermal field, Taupo Volcanic Zone, New Zealand
C. Rissmann, B. Christenson, Cynthia A. Werner, M. Leybourne, J. Cole, D. Gravley
2012, Applied Geochemistry (27) 223-239
Carbon dioxide emissions and heat flow have been determined from the Ohaaki hydrothermal field, Taupo Volcanic Zone (TVZ), New Zealand following 20 a of production (116 MWe). Soil CO2 degassing was quantified with 2663 CO2 flux measurements using the accumulation chamber method, and 2563 soil temperatures were measured and converted to equivalent heat flow...
Population fragmentation and inter-ecosystem movements of grizzly bears in Western Canada and the Northern United States
M.F. Proctor, David Paetkau, B. N. McLellan, G.B. Stenhouse, K.C. Kendall, R.D. Mace, W.F. Kasworm, C. Servheen, C.L. Lausen, M.L. Gibeau, W.L. Wakkinen, M.A. Haroldson, G. Mowat, C.D. Apps, L.M. Ciarniello, R.M.R. Barclay, M.S. Boyce, C.C. Schwartz, C. Strobeck
2012, Wildlife Monographs 1-46
Population fragmentation compromises population viability, reduces a species ability to respond to climate change, and ultimately may reduce biodiversity. We studied the current state and potential causes of fragmentation in grizzly bears over approximately 1,000,000 km 2 of western Canada, the northern United States (US), and southeast Alaska. We...
Wolf population dynamics in the U.S. Northern Rocky Mountains are affected by recruitment and human-caused mortality
J.A. Gude, M.S. Mitchell, Robin E. Russell, C.A. Sime, E.E. Bangs, L.D. Mech, R.R. Ream
2012, Journal of Wildlife Management (76) 108-118
Reliable analyses can help wildlife managers make good decisions, which are particularly critical for controversial decisions such as wolf (Canis lupus) harvest. Creel and Rotella (2010) recently predicted substantial population declines in Montana wolf populations due to harvest, in contrast to predictions made by Montana Fish, Wildlife and Parks (MFWP)....
Recent paleorecords document rising mercury contamination in Lake Tanganyika
Christopher H. Conaway, Peter W. Swarzenski, A.S. Cohen
2012, Applied Geochemistry (27) 352-359
Recent Lake Tanganyika Hg deposition records were derived using 14C and excess 210Pb geochronometers in sediment cores collected from two contrasting depositional environments: the Kalya Platform, located mid-lake and more removed from watershed impacts, and the Nyasanga/Kahama River delta region, located close to the lake’s shoreline north of Kigoma. At the Kalya...
Evaluating Re-Os systematics in organic-rich sedimentary rocks in response to petroleum generation using hydrous pyrolysis experiments
A.D. Rooney, D. Selby, M. D. Lewan, P. G. Lillis, J.-P. Houzay
2012, Geochimica et Cosmochimica Acta (77) 275-291
Successful application of the 187Re–187Os geochronometer has enabled the determination of accurate and precise depositional ages for organic-rich sedimentary rocks (ORS) as well as establishing timing constraints of petroleum generation. However, we do not fully understand the systematics and transfer behaviour of Re and Os between ORS and petroleum products...
Oxygen and sulfur isotope systematics of sulfate produced during abiotic and bacterial oxidation of sphalerite and elemental sulfur
N. Balci, B. Mayer, W. C. Pat Shanks III, K.W. Mandernack
2012, Geochimica et Cosmochimica Acta (77) 335-351
Studies of metal sulfide oxidation in acid mine drainage (AMD) systems have primarily focused on pyrite oxidation, although acid soluble sulfides (e.g., ZnS) are predominantly responsible for the release of toxic metals. We conducted a series of biological and abiotic laboratory oxidation experiments with pure and Fe-bearing sphalerite (ZnS &...
Water utilization of the Cretaceous Mussentuchit Member local vertebrate fauna, Cedar Mountain Formation, Utah, USA: Using oxygen isotopic composition of phosphate
C.A. Suarez, Luis A. Gonzalez, G.A. Ludvigson, R.L. Cifelli, E. Tremain
2012, Palaeogeography, Palaeoclimatology, Palaeoecology (313-314) 78-92
While the oxygen isotopic composition of pedogenic carbonate has successfully been used to address the effects of global climate change on the hydrologic cycle, detailed regional paleohydrologic studies are lacking. Since the hydrologic cycle can vary extensively on local or regional scales due to events such as such as...
Updated determination of stress parameters for nine well-recorded earthquakes in eastern North America
David M. Boore
2012, Seismological Research Letters (83) 190-199
Stress parameters (Δσ) are determined for nine relatively well-recorded earthquakes in eastern North America for ten attenuation models. This is an update of a previous study by Boore et al. (2010). New to this paper are observations from the 2010 Val des Bois earthquake, additional observations for the 1988 Saguenay and 2005...
Photodissolution of soil organic matter
L.M. Mayer, K.R. Thornton, L.L. Schick, J.D. Jastrow, Jennifer W. Harden
2012, Geoderma (170) 314-321
Sunlight has been shown to enhance loss of organic matter from aquatic sediments and terrestrial plant litter, so we tested for similar reactions in mineral soil horizons. Losses of up to a third of particulate organic carbon occurred after continuous exposure to full-strength sunlight for dozens of hours, with similar...
Evaluating the demographic buffering hypothesis with vital rates estimated for Weddell seals from 30years of mark-recapture data
J.J. Rotella, William A. Link, T. Chambert, G.E. Stauffer, R.A. Garrott
2012, Journal of Animal Ecology (81) 162-173
1. Life‐history theory predicts that those vital rates that make larger contributions to population growth rate ought to be more strongly buffered against environmental variability than are those that are less important. Despite the importance of the theory for predicting demographic responses to changes in the environment, it is not yet...
Discovery and characterization of secretory IgD in rainbow trout: secretory IgD is produced through a novel splicing mechanism
F. Ramirez-Gomez, W. Greene, K. Rego, J.D. Hansen, G. Costa, P. Kataria, E.S. Bromage
2012, Journal of Immunology (188) 1341-1349
The gene encoding IgH δ has been found in all species of teleosts studied to date. However, catfish (Ictalurus punctatus) is the only species of fish in which a secretory form of IgD has been characterized, and it occurs through the use of a dedicated δ-secretory exon, which is absent...
Methylation of Hg downstream from the Bonanza Hg mine, Oregon
John E. Gray, Mark E. Hines, David P. Krabbenhoft, Bryn Thoms
2012, Applied Geochemistry (27) 106-114
Speciation of Hg and conversion to methyl-Hg were evaluated in stream sediment, stream water, and aquatic snails collected downstream from the Bonanza Hg mine, Oregon. Total production from the Bonanza mine was >1360t of Hg, during mining from the late 1800s to 1960, ranking it as an intermediate sized Hg...
The hidden cost of wildfires: Economic valuation of health effects of wildfire smoke exposure in Southern California
L.A. Richardson, P.A. Champ, J.B. Loomis
2012, Journal of Forest Economics (18) 14-35
There is a growing concern that human health impacts from exposure to wildfire smoke are ignored in estimates of monetized damages from wildfires. Current research highlights the need for better data collection and analysis of these impacts. Using unique primary data, this paper quantifies the economic cost of health effects...
Rapid microsatellite identification from illumina paired-end genomic sequencing in two birds and a snake
T.A. Castoe, A.W. Poole, A. P. J. de Koning, K.L. Jones, D.F. Tomback, Sara J. Oyler-McCance, Jennifer A. Fike, S.L. Lance, J.W. Streicher, E.N. Smith, D.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...
Why farmers adopt best management practice in the United States: A meta-analysis of the adoption literature
Adam Baumgart-Getz, Linda Stalker Prokopy, Kristin Floress
2012, Journal of Environmental Management (96) 17-25
This meta-analysis of both published and unpublished studies assesses factors believed to influence adoption of agricultural Best Management Practices in the United States. Using an established statistical technique to summarize the adoption literature in the United States, we identified the following variables as having the largest impact on adoption: access...
Assessment of pingo distribution and morphometry using an IfSAR derived digital surface model, western Arctic Coastal Plain, Northern Alaska
Benjamin M. Jones, G. Grosse, Kenneth M. Hinkel, C.D. Arp, S. Walker, R.A. Beck, J. P. Galloway
2012, Geomorphology (138) 1-14
Pingos are circular to elongate ice-cored mounds that form by injection and freezing of pressurized water in near-surface permafrost. Here we use a digital surface model (DSM) derived from an airborne Interferometric Synthetic Aperture Radar (IfSAR) system to assess the distribution and morphometry of pingos within a 40,000 km2 area on the...
A preliminary assessment of the spatial sources of contemporary suspended sediment in the Ohio River basin, United States, using water quality data from the NASQAN programme in a source tracing procedure
Y.-S. Zhang, A.L. Collins, Arthur J. Horowitz
2012, Hydrological Processes (26) 326-334
Reliable information on catchment scale suspended sediment sources is required to inform the design of management strategies for helping abate the numerous environmental issues associated with enhanced sediment mobilization and off‐site loadings. Since sediment fingerprinting techniques avoid many of the logistical constraints associated with using more traditional indirect measurement methods...
Empirical methods for detecting regional trends and other spatial expressions in antrim shale gas productivity, with implications for improving resource projections using local nonparametric estimation techniques
Timothy C. Coburn, Philip A. Freeman, Emil D. Attanasi
2012, Natural Resources Research (21) 1-21
The primary objectives of this research were to (1) investigate empirical methods for establishing regional trends in unconventional gas resources as exhibited by historical production data and (2) determine whether or not incorporating additional knowledge of a regional trend in a suite of previously established local nonparametric resource prediction algorithms...