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Page 1231, results 30751 - 30775

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Publication Extents

Not all publications have extents, not all extents are completely accurate
Spatial genetic structure of bristle-thighed curlews (Numenius tahitiensis): Breeding area differentiation not reflected on the non-breeding grounds
Sarah A. Sonsthagen, T. Lee Tibbitts, Robert E. Gill Jr., Ian S. Williams, Sandra L. Talbot
2015, Conservation Genetics (16) 223-233
Migratory birds occupy geographically and ecologically disparate areas during their annual cycle with conditions on breeding and non-breeding grounds playing separate and important roles in population dynamics. We used data from nuclear microsatellite and mitochondrial DNA control region loci to assess the breeding and non-breeding spatial genetic structure of a...
Integrated survival analysis using an event-time approach in a Bayesian framework
Daniel P. Walsh, VJ Dreitz, Dennis M. Heisey
2015, Ecology and Evolution (5) 769-780
Event-time or continuous-time statistical approaches have been applied throughout the biostatistical literature and have led to numerous scientific advances. However, these techniques have traditionally relied on knowing failure times. This has limited application of these analyses, particularly, within the ecological field where fates of marked animals may be unknown. To...
Site-scale disturbance and habitat development best predict an index of amphibian biotic integrity in Ohio shrub and forested wetlands
Mick Micacchion, Martin A. Stapanian, Jean V. Adams
2015, Wetlands (35) 509-519
We determined the best predictors of an index of amphibian biotic integrity calculated from 54 shrub and forested wetlands in Ohio, USA using a two-step sequential holdout validation procedure. We considered 13 variables as predictors: four metrics of wetland condition from the Ohio Rapid Assessment Method (ORAM), a wetland vegetation...
Ephemeral stream reaches preserve the evolutionary and distributional history of threespine stickleback in the Santa Clara and Ventura River watersheds of southern California
Jonathan Q. Richmond, David K. Jacobs, Adam R. Backlin, Camm C. Swift, Chris Dellith, Robert N. Fisher
2015, Conservation Genetics (16) 85-101
Much remains to be understood about the evolutionary history and contemporary landscape genetics of unarmored threespine stickleback in southern California, where populations collectively referred to as Gasterosteus aculeatus williamsoni have severely declined over the past 70+ years and are now endangered. We used mitochondrial sequence and microsatellite data to assess...
An open-population hierarchical distance sampling model
Rachel Sollmann, Beth Gardner, Richard B Chandler, J. Andrew Royle, T Scott Sillett
2015, Ecology (96) 325-331
Modeling population dynamics while accounting for imperfect detection is essential to monitoring programs. Distance sampling allows estimating population size while accounting for imperfect detection, but existing methods do not allow for direct estimation of demographic parameters. We develop a model that uses temporal correlation in abundance arising from underlying population...
Vegetation and non-native ungulate monitoring at the Big Island National Wildlife Refuge Complex 2010–2014.
Steven C. Hess, Christina R. Leopold, Steven J. Kendall
2015, Technical Report HCSU-062
The Hakalau Forest Unit (HFU) of Big Island National Wildlife Refuge Complex (BINWRC) has intensively managed feral cattle (Bos taurus) and pigs (Sus scrofa) and monitored non-native ungulate presence and distribution during surveys of all managed areas since 1988. We: 1) provide results from recent ungulate surveys at HFU to...
Advancing the science of microbial symbiosis to support invasive species management: a case study on Phragmites in the Great Lakes
Kurt P. Kowalski, Charles W. Bacon, Wesley A. Bickford, Heather A. Braun, Keith Clay, Michele Leduc-Lapierre, Elizabeth Lillard, Melissa K. McCormick, Eric Nelson, Monica Torres, James W. C. White, Douglas A. Wilcox
2015, Frontiers in Microbiology (6)
A growing body of literature supports microbial symbiosis as a foundational principle for the competitive success of invasive plant species. Further exploration of the relationships between invasive species and their associated microbiomes, as well as the interactions with the microbiomes of native species, can lead to key new insights into...
Reducing nitrogen export from the corn belt to the Gulf of Mexico: agricultural strategies for remediating hypoxia
Eileen McLellan, Dale M. Robertson, Keith Schilling, Mark Tomer, Jill Kostel, Douglas G. Smith, Kevin King
2015, Journal of the American Water Resources Association (51) 263-289
SPAtially Referenced Regression on Watershed models developed for the Upper Midwest were used to help evaluate the nitrogen-load reductions likely to be achieved by a variety of agricultural conservation practices in the Upper Mississippi-Ohio River Basin (UMORB) and to compare these reductions to the 45% nitrogen-load reduction proposed to remediate...
Nest visits and capture events affect breeding success of Yellow-billed and Pacific loons
Brian D. Uher-Koch, Joel A. Schmutz, Kenneth G. Wright
2015, Condor (7) 121-129
Accurate estimates of breeding success are essential for understanding population dynamics and for managing populations. Unfortunately, research activities to collect these data can negatively impact the breeding success of the study species and bias estimates of breeding success. Despite the potential for negative impacts, few studies have documented the effect...
Factors influencing CO2 and CH4 emissions from coastal wetlands in the Liaohe Delta, northeast China
Linda Olsson, Siyuan Ye, Xueyang Yu, Mengjie Wei, Ken W. Krauss, Hans Brix
2015, Biogeosciences Discussions (12) 3469-3503
Many factors are known to influence greenhouse gas emissions from coastal wetlands, but it is still unclear which factors are most important under field conditions when they are all acting simultaneously. The objective of this study was to assess the effects of water table, salinity, soil temperature and vegetation on...
The cost of reproduction: differential resource specialization in female and male California sea otters
Emma A. Elliott Smith, Seth D. Newsome, James A. Estes, M. Tim Tinker
2015, Oecologia (178) 17-29
Intraspecific variation in behavior and diet can have important consequences for population and ecosystem dynamics. Here, we examine how differences in reproductive investment and spatial ecology influence individual diet specialization in male and female southern sea otters (Enhydra lutris nereis). We hypothesize that greater reproductive constraints and smaller home...
Tectonic activity as a significant source of crustal tetrafluoromethane emissions to the atmosphere: observations in groundwaters along the San Andreas Fault
Daniel A. Deeds, Justin T. Kulongoski, Jens Muhle, Ray F. Weiss
2015, Earth and Planetary Science Letters (412) 163-172
Tetrafluoromethane (CF4) concentrations were measured in 14 groundwater samples from the Cuyama Valley, Mil Potrero and Cuddy Valley aquifers along the Big Bend section of the San Andreas Fault System (SAFS) in California to assess whether tectonic activity in this region is a significant source of crustal CF4 to the...
Magmatic gas emissions at Holocene volcanic features near Mono Lake, California, and their relation to regional magmatism
D. Bergfeld, William C. Evans, James F. Howle, Andrew G. Hunt
2015, Journal of Volcanology and Geothermal Research (292) 70-83
Silicic lavas have erupted repeatedly in the Mono Basin over the past few thousand years, forming the massive domes and coulees of the Mono Craters chain and the smaller island vents in Mono Lake. We report here on the first systematic study of magmatic CO2 emissions from these features, conducted during...
Evaluation of satellite rainfall estimates for drought and flood monitoring in Mozambique
Carolien Tote, Domingos Patricio, Hendrik Boogaard, Raymond van der Wijngaart, Elena Tarnavsky, Christopher C. Funk
2015, Remote Sensing (7) 1758-1776
Satellite derived rainfall products are useful for drought and flood early warning and overcome the problem of sparse, unevenly distributed and erratic rain gauge observations, provided their accuracy is well known. Mozambique is highly vulnerable to extreme weather events such as major droughts and floods and thus, an understanding of...
Aeolian responses to climate variability during the past century on Mesquite Lake Playa, Mojave Desert
John W. Whitney, George N. Breit, S.E. Buckingham, Richard L. Reynolds, Rian C. Bogle, Lifeng Luo, Harland L. Goldstein, John M. Vogel
2015, Geomorphology (230) 13-25
The erosion and deposition of sediments by wind from 1901 to 2013 have created large changes in surface features of Mesquite Lake playa in the Mojave Desert. The decadal scale recurrence of sand-sheet development, migration, and merging with older dunes appears related to decadal climatic changes of drought and wetness...
Anomalous solute transport in saturated porous media: Relating transport model parameters to electrical and nuclear magnetic resonance properties
Ryan D Swanson, Andrew Binley, Kristina Keating, Samantha France, Gordon Osterman, Frederick D. Day-Lewis, Kamini Singha
2015, Water Resources Research (51) 1264-1283
The advection-dispersion equation (ADE) fails to describe commonly observed non-Fickian solute transport in saturated porous media, necessitating the use of other models such as the dual-domain mass-transfer (DDMT) model. DDMT model parameters are commonly calibrated via curve fitting, providing little insight into the relation between effective parameters and physical properties...
Sources of fine sediment stored in agricultural lowland streams, Midwest, USA
Jasmeet Lamba, Anita M. Thompson, K.G. Karthikeyan, Faith A. Fitzpatrick
2015, Geomorphology (236) 44-53
Agricultural activities can accelerate the offsite transport of productive soil from fields leading to stream water quality degradation. Identification of the nature and relative contribution of different sources to fine-grained sediment (e.g., silts, clays) in streams is important to effectively focus agricultural best management...
Development of a new semi-analytical model for cross-borehole flow experiments in fractured media
Delphine Roubinet, James Irving, Frederick D. Day-Lewis
2015, Advances in Water Resources (76) 97-108
Analysis of borehole flow logs is a valuable technique for identifying the presence of fractures in the subsurface and estimating properties such as fracture connectivity, transmissivity and storativity. However, such estimation requires the development of analytical and/or numerical modeling tools that are well adapted to the complexity of the problem....
Hillslope run-off thresholds with shrink–swell clay soils
Ryan D. Stewart, Majdi R. Abou Najm, David E. Rupp, John W. Lane Jr., Hamil C. Uribe, Jose Luis Arumi, John S. Selker
2015, Hydrological Processes (29) 557-571
Irrigation experiments on 12 instrumented field plots were used to assess the impact of dynamic soil crack networks on infiltration and run-off. During applications of intensity similar to a heavy rainstorm, water was seen being preferentially delivered within the soil profile. However, run-off was not observed until soil water content...
The role of water in unconventional in situ energy resource extraction technologies
Tanya J. Gallegos, Carleton R. Bern, Justin E. Birdwell, Seth S. Haines, Mark A. Engle
Satinder Ahuja, editor(s)
2015, Book chapter, Food, energy, and water: The chemistry connection
Global trends toward developing new energy resources from lower grade, larger tonnage deposits that are not generally accessible using “conventional” extraction methods involve variations of subsurface in situ extraction techniques including in situ oil shale retorting, hydraulic fracturing of petroleum reservoirs, and in situ recovery of uranium. Although these methods are...
Time scales of porphyry Cu deposit formation: insights from titanium diffusion in quartz
Celestine N. Mercer, Mark H. Reed, Cameron M. Mercer
2015, Economic Geology (110) 587-602
Porphyry dikes and hydrothermal veins from the porphyry Cu-Mo deposit at Butte, Montana, contain multiple generations of quartz that are distinct in scanning electron microscope-cathodoluminescence (SEM-CL) images and in Ti concentrations. A comparison of microprobe trace element profiles and maps to SEM-CL images shows that the concentration of Ti in...
Temperature effects induced by climate change on the growth and consumption by salmonines in Lakes Michigan and Huron
Yu-Chun Kao, Charles P. Madenjian, David B. Bunnell, Brent M. Lofgren, Marjorie Perroud
2015, Environmental Biology of Fishes (98) 1089-1104
We used bioenergetics models to investigate temperature effects induced by climate change on the growth and consumption by Chinook salmon Oncorhynchus tshawytscha, lake trout Salvelinus namaycush, and steelhead O. mykiss in Lakes Michigan and Huron. We updated biological inputs to account for recent changes in the food webs and used temperature inputs in response...
Flow cytometric method for measuring chromatin fragmentation in fixed sperm from yellow perch (Perca flavescens)
Jill A. Jenkins, Rassa O. Draugelis-Dale, Alfred E. Pinkney, Luke R. Iwanowicz, Vicki Blazer
2015, Theriogenology (83) 920-931
Declining harvests of yellow perch, Perca flavescens, in urbanized watersheds of Chesapeake Bay have prompted investigations of their reproductive fitness. The purpose of this study was to establish a flow cytometric technique for DNA analysis of fixed samples sent from the field to provide reliable gamete quality measurements. Similar to the...
Mineral Resource of the Month: Antimony
David E. Guberman
2015, Earth Magazine (February 2015)
Antimony is a lustrous silvery-white semimetal or metalloid. Archaeological and historical studies indicate that antimony and its mineral sulfides have been used by humans for at least six millennia. The alchemist Basil Valentine is sometimes credited with “discovering” the element; he described the extraction of metallic antimony from stibnite in...
Vegetation burn severity mapping using Landsat-8 and WorldView-2
Zhuoting Wu, Barry R. Middleton, Robert Hetzler, John M. Vogel, Dennis G. Dye
2015, Photogrammetric Engineering and Remote Sensing (2) 143-154
We used remotely sensed data from the Landsat-8 and WorldView-2 satellites to estimate vegetation burn severity of the Creek Fire on the San Carlos Apache Reservation, where wildfire occurrences affect the Tribe's crucial livestock and logging industries. Accurate pre- and post-fire canopy maps at high (0.5-meter) resolution were created from...