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Page 1170, results 29226 - 29250

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Publication Extents

Not all publications have extents, not all extents are completely accurate
Factors affecting individual foraging specialization and temporal diet stability across the range of a large “generalist” apex predator
Adam E. Rosenblatt, James C. Nifong, Michael R. Heithaus, Frank J. Mazzotti, Michael S. Cherkiss, Brian M. Jeffery, Ruth M. Elsey, Rachel A. Decker, Brian R. Silliman, Louis J. Guillette Jr., Russell H. Lowers, Justin C. Larson
2015, Oecologia (178) 5-16
Individual niche specialization (INS) is increasingly recognized as an important component of ecological and evolutionary dynamics. However, most studies that have investigated INS have focused on the effects of niche width and inter- and intraspecific competition on INS in small-bodied species for short time periods, with less attention paid to...
Estimating global natural wetland methane emissions using process modelling: spatio-temporal patterns and contributions to atmospheric methane fluctuations
Qiuan Zhu, Changhui Peng, Huai Chen, Xiuqin Fang, Jinxun Liu, Hong Jiang, Yanzheng Yang, Gang Yang
2015, Global Ecology and Biogeography (24) 959-972
Aim The fluctuations of atmospheric methane (CH4) that have occurred in recent decades are not fully understood, particularly with regard to the contribution from wetlands. The application of spatially explicit parameters has been suggested as an effective method for reducing uncertainties in bottom-up approaches to wetland CH4 emissions,...
High-tech or field techs: Radio-telemetry is a cost-effective method for reducing bias in songbird nest searching
Sean M. Peterson, Henry M. Streby, Justin A. Lehman, Gunnar R. Kramer, Alexander C. Fish, David E. Andersen
2015, The Condor (117) 386-395
We compared the efficacy of standard nest-searching methods with finding nests via radio-tagged birds to assess how search technique influenced our determination of nest-site characteristics and nest success for Golden-winged Warblers (Vermivora chrysoptera). We also evaluated the cost-effectiveness of using radio-tagged birds to find nests. Using standard nest-searching techniques for...
Evaluating a satellite-based seasonal evapotranspiration product and identifying its relationship with other satellite-derived products and crop yield: A case study for Ethiopia
Tsegaye Tadesse, Gabriel B. Senay, Getachew Berhan, Teshome Regassa, Shimelis Beyene
2015, International Journal of Applied Earth Observation and Geoinformation (40) 39-54
Satellite-derived evapotranspiration anomalies and normalized difference vegetation index (NDVI) products from Moderate Resolution Imaging Spectroradiometer (MODIS) data are currently used for African agricultural drought monitoring and food security status assessment. In this study, a process to evaluate satellite-derived evapotranspiration (ETa) products with a geospatial statistical exploratory technique that uses NDVI,...
Impact of fishing and stocking practices on Coregonid diversity
Orlane Anneville, Emilien Lasne, Jean Guillard, Reiner Eckmann, Jason D. Stockwell, Christian Gillet, Daniel Yule
2015, Food and Nutrition Sciences (6) 1045-1055
Fish species diversity can be lost through interacting stressors including habitat loss, stocking and overfishing. Although a multitude of stressors have played a role in the global decline of coregonid (Coregonus spp.) diversity, a number of contemporary studies have identified habitat loss stemming from eutrophication as the primary cause. Unfortunately,...
Reducing fertilizer-nitrogen losses from rowcrop landscapes: Insights and implications from a spatially explicit watershed model
Eileen McLellan, Keith Schilling, Dale M. Robertson
2015, Journal of the American Water Resources Association (51) 1003-1019
We present conceptual and quantitative models that predict changes in fertilizer-derived nitrogen delivery from rowcrop landscapes caused by agricultural conservation efforts implemented to reduce nutrient inputs and transport and increase nutrient retention in the landscape. To evaluate the relative importance of changes in the sources, transport, and sinks of fertilizer-derived...
Resilience of ponderosa and lodgepole pine forests to mountain pine beetle disturbance and limited regeneration
Jenny S. Briggs, Todd Hawbaker, Don Vandendriesche
2015, Forest Science (61) 689-702
After causing widespread mortality in lodgepole pine forests in North America, the mountain pine beetle (MPB) has recently also affected ponderosa pine, an alternate host species that may have different levels of resilience to this disturbance. We collected field data in ponderosa pine- and lodgepole pine-dominated forests attacked by MPB...
Framework for modeling urban restoration resilience time in the aftermath of an extreme event
Varun Ramachandran, Suzanna K. Long, Thomas G. Shoberg, Steven Corns, Héctor Carlo
2015, Natural Hazards Review 1-11
The impacts of extreme events continue long after the emergency response has terminated. Effective reconstruction of supply-chain strategic infrastructure (SCSI) elements is essential for postevent recovery and the reconnectivity of a region with the outside. This study uses an interdisciplinary approach to develop a comprehensive framework to model resilience time....
Myths and facts on wastewater injection, hydraulic fracturing, enhanced oil recovery, and induced seismicity
Justin L. Rubinstein, Alireza Babaie Mahani
2015, Seismological Research Letters (86) 1060-1067
The central United States has undergone a dramatic increase in seismicity over the past 6 years (Fig. 1), rising from an average of 24 M≥3 earthquakes per year in the years 1973–2008 to an average of 193 M≥3 earthquakes in 2009–2014, with 688 occurring in 2014 alone. Multiple damaging earthquakes have...
Holocene variability in the intensity of wind-gap upwelling in the tropical eastern Pacific
Lauren T. Toth, Richard B. Aronson, Hai Cheng, R. Lawrence Edwards
2015, Paleoceanography (30) 1113-1131
Wind-driven upwelling in Pacific Panamá is a significant source of oceanographic variability in the tropical eastern Pacific. This upwelling system provides a critical teleconnection between the Atlantic and tropical Pacific that may impact climate variability on a global scale. Despite its importance to oceanographic circulation, ecology, and climate, little is...
Influence of in ovo mercury exposure, lake acidity, and other factors on common loon egg and chick quality in Wisconsin
Kevin P. Kenow, Michael W. Meyer, Ronald Rossmann, Brian R. Gray, Michael T. Arts
2015, Environmental Toxicology and Chemistry (34) 1870-1880
A field study was conducted in Wisconsin (USA) to characterize in ovo mercury (Hg) exposure in common loons (Gavia immer). Total Hg mass fractions ranged from 0.17 mg/g to 1.23mg/g wet weight in eggs collected from nests on lakes representing a wide range of pH (5.0–8.1) and were modeled as...
Limits to benthic feeding by eiders in a vital Arctic migration corridor due to localized prey and changing sea ice
James R. Lovvorn, Aariel R. Rocha, Stephen C. Jewett, Douglas Dasher, Steffen Oppel, Abby Powell
2015, Progress in Oceanography (136) 162-174
Four species of threatened or declining eider ducks that nest in the Arctic migrate through the northeast Chukchi Sea, where anticipated industrial development may require prioritizing areas for conservation. In this nearshore corridor (10–40 m depth), the eiders’ access to benthic prey during the spring is restricted to variable areas of...
Valuing geospatial information: Using the contingent valuation method to estimate the economic benefits of Landsat satellite imagery
John B. Loomis, Steve Koontz, Holly M. Miller, Leslie A. Richardson
2015, Photogrammetric Engineering and Remote Sensing (81) 647-656
While the U.S. government does not charge for downloading Landsat images, the images have value to users. This paper demonstrates a method that can value Landsat and other imagery to users. A survey of downloaders of Landsat images found: (a) established US users have a mean value of $912 USD...
Adult mortality probability and nest predation rates explain parental effort in warming eggs with consequences for embryonic development time
Thomas E. Martin, Juan C. Oteyza, Andy J. Boyce, Penn Lloyd, Riccardo Ton
2015, The American Naturalist (186) 223-236
Parental behavior and effort vary extensively among species. Life-history theory suggests that age-specific mortality could cause this interspecific variation, but past tests have focused on fecundity as the measure of parental effort. Fecundity can cause costs of reproduction that confuse whether mortality is the cause or the consequence of parental...
Ground-truthing electrical resistivity methods in support of submarine groundwater discharge studies: Examples from Hawaii, Washington, and California
Cordell Johnson, Peter W. Swarzenski, Christina M. Richardson, Christopher G. Smith, Kevin D. Kroeger, Priya M. Ganguli
2015, Journal of Environmental & Engineering Geophysics (20) 81-87
Submarine groundwater discharge (SGD) is an important conduit that links terrestrial and marine environments. SGD conveys both water and water-borne constituents into coastal waters, where these inflows may impact near-shore ecosystem health and sustainability. Multichannel electrical resistivity techniques have proven to be a powerful tool to examine scales and...
A global reference database from very high resolution commercial satellite data and methodology for application to Landsat derived 30 m continuous field tree cover data
Bruce Pengra, Jordan Long, Devendra Dahal, Stephen V. Stehman, Thomas R. Loveland
2015, Remote Sensing of Environment (165) 234-248
The methodology for selection, creation, and application of a global remote sensing validation dataset using high resolution commercial satellite data is presented. High resolution data are obtained for a stratified random sample of 500 primary sampling units (5 km × 5 km sample blocks), where the stratification based on Köppen...
Comparison of reintroduction and enhancement effects on metapopulation viability
Samniqueka J Halsey, Timothy J. Bell, Kathryn McEachern, Noel B. Pavlovic
2015, Restoration Ecology (23) 375-384
Metapopulation viability depends upon a balance of extinction and colonization of local habitats by a species. Mechanisms that can affect this balance include physical characteristics related to natural processes (e.g. succession) as well as anthropogenic actions. Plant restorations can help to produce favorable metapopulation dynamics and consequently increase viability; however,...
Water masses, ocean fronts, and the structure of Antarctic seabird communities: putting the eastern Bellingshausen Sea in perspective
Christine A. Ribic, David G. Ainley, R. Glenn Ford, William R. Fraser, Cynthia T. Tynan, Eric J. Woehler
2015, Deep-Sea Research Part II: Topical Studies in Oceanography (58) 1695-1709
Waters off the western Antarctic Peninsula (i.e., the eastern Bellingshausen Sea) are unusually complex owing to the convergence of several major fronts. Determining the relative influence of fronts on occurrence patterns of top-trophic species in that area, therefore, has been challenging. In one of the few ocean-wide seabird data syntheses,...
Ignimbrites to batholiths: integrating perspectives from geological, geophysical, and geochronological data
Peter W. Lipman, Olivier Bachmann
2015, Geosphere (11) 705-743
Multistage histories of incremental accumulation, fractionation, and solidification during construction of large subvolcanic magma bodies that remained sufficiently liquid to erupt are recorded by Tertiary ignimbrites, source calderas, and granitoid intrusions associated with large gravity lows at the Southern Rocky Mountain volcanic field (SRMVF). Geophysical data combined with geological constraints...
Spatial scaling patterns and functional redundancies in a changing boreal lake landscape
David G. Angeler, Craig R. Allen, Daniel R. Uden, Richard K. Johnson
2015, Ecosystems (18) 889-902
Global transformations extend beyond local habitats; therefore, larger-scale approaches are needed to assess community-level responses and resilience to unfolding environmental changes. Using longterm data (1996–2011), we evaluated spatial patterns and functional redundancies in the littoral invertebrate communities of 85 Swedish lakes, with the objective of assessing their potential resilience to...
Oyster reef restoration supports increased nekton biomass and potential commercial fishery value
Austin T. Humphries, Megan K. LaPeyre
2015, PeerJ (3) 1-19
Across the globe, discussions centered on the value of nature drive many conservation and restoration decisions. As a result, justification for management activities increasingly asks for two lines of evidence: (1) biological proof of augmented ecosystem function or service, and (2) monetary valuation of these services. For oyster reefs, which...
Preserved filamentous microbial biosignatures in the Brick Flat gossan, Iron Mountain, California
Amy J. Williams, Dawn Y. Sumner, Charles N. Alpers, Suniti Karunatillake, Beda A Hofmann
2015, Astrobiology (15) 637-668
A variety of actively precipitating mineral environments preserve morphological evidence of microbial biosignatures. One such environment with preserved microbial biosignatures is the oxidized portion of a massive sulfide deposit, or gossan, such as that at Iron Mountain, California. This gossan may serve as a mineralogical analogue to some ancient martian...
Impact of experimental habitat manipulation on northern bobwhite survival
David C. Peters, Jarred M. Brooke, Evan P. Tanner, Ashley M. Unger, Patrick D. Keyser, Craig A. Harper, Joseph D. Clark, John J. Morgan
2015, Journal of Wildlife Management (79) 605-617
Habitat management for northern bobwhite (Colinus virginianus) should affect vital rates, but direct linkages with survival are not well documented; therefore, we implemented an experiment to evaluate those responses. We conducted our experiment on a reclaimed surface mine, a novel landscape where conditions were considered sub-optimal because of the dominance...
Metallogeny, exploitation and environmental impact of the Mt. Amiata mercury ore district (Southern Tuscany, Italy)
V. Rimondi, L. Chiarantini, P. Lattanzi, M. Benvenuti, M. Beutel, A. Colica, P. Costagliola, F. Di Benedetto, G. Gabbani, John E. Gray, E. Pandeli, G. Pattelli, M. Paolieri, G. Ruggieri
2015, Italian Journal of Geosciences (134) 323-336
The Mt. Amiata mining district (Southern Tuscany, Italy) is a world class Hg district, with a cumulate production of more than 100,000 tonnes of Hg, mostly occurring between 1870 and 1980. The Hg mineralization at Mt. Amiata is younger than 0.3 Ma, and is directly related to shallow hydrothermal...
Book review: Biology and conservation of North American tortoises
David Munoz, Christina M. Aiello
2015, Herpetological Review (46) 288-289
The charismatic North American tortoises hold a special place in our culture and natural history. Despite the perseverance of these tortoises over millions of years, biologists now question their ability to persist into the future. In light of documented declines, habitat loss, and numerous threats to tortoise populations, the editors...