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Full-Text Articles in Physical Sciences and Mathematics

Terrestrial Ecosystem Process Model Biome-Bgcmuso V4.0: Summary Of Improvements And New Modeling Possibilities, Dóra Hidy, Zoltán Barcza, Hrvoje Marjanovi´C, Maša Zorana Ostrogovi´C Sever, Laura Dobor, Györgyi Gelybó, Nándor Fodor, Krisztina Pintér, Galina Churkina, Steven Running, Peter Thornton, Gianni Bellocchi, László Haszpra, Ferenc Horváth, Andrew E. Suyker, Zoltán Nagy Dec 2016

Terrestrial Ecosystem Process Model Biome-Bgcmuso V4.0: Summary Of Improvements And New Modeling Possibilities, Dóra Hidy, Zoltán Barcza, Hrvoje Marjanovi´C, Maša Zorana Ostrogovi´C Sever, Laura Dobor, Györgyi Gelybó, Nándor Fodor, Krisztina Pintér, Galina Churkina, Steven Running, Peter Thornton, Gianni Bellocchi, László Haszpra, Ferenc Horváth, Andrew E. Suyker, Zoltán Nagy

School of Natural Resources: Faculty Publications

The process-based biogeochemical model Biome- BGC was enhanced to improve its ability to simulate carbon, nitrogen, and water cycles of various terrestrial ecosystems under contrasting management activities. Biome-BGC version 4.1.1 was used as a base model. Improvements included addition of new modules such as the multilayer soil module, implementation of processes related to soil moisture and nitrogen balance, soil-moisture-related plant senescence, and phenological development. Vegetation management modules with annually varying options were also implemented to simulate management practices of grasslands (mowing, grazing), croplands (ploughing, fertilizer application, planting, harvesting), and forests (thinning). New carbon and nitrogen pools have been defined to …


Freshwater Vertebrate And Invertebrate Diversity Patterns In An Andean-Amazon Basin: Implications For Conservation Efforts, Janeth Lessmann, Juan M. Guayasamin, Kayce L. Casner, Alexander S. Flecker, W. Chris Funk, Cameron K. Ghalambor, Brian A. Gill, Iván Jácome- Negrete, Boris C. Kondratieff, Leroy N. Poff, José Schreckinger, Steven A. Thomas, Eduardo Toral-Contreras, Kelly R. Zamudio, Andrea C. Encalada Sep 2016

Freshwater Vertebrate And Invertebrate Diversity Patterns In An Andean-Amazon Basin: Implications For Conservation Efforts, Janeth Lessmann, Juan M. Guayasamin, Kayce L. Casner, Alexander S. Flecker, W. Chris Funk, Cameron K. Ghalambor, Brian A. Gill, Iván Jácome- Negrete, Boris C. Kondratieff, Leroy N. Poff, José Schreckinger, Steven A. Thomas, Eduardo Toral-Contreras, Kelly R. Zamudio, Andrea C. Encalada

School of Natural Resources: Faculty Publications

The Napo Basin in Ecuador is an important drainage of the Amazon Basin, the most biodiverse ecosystem for freshwater species. At the same time, this basin has conspicuous information gaps on its biodiversity patterns and human threats. Here, we estimated the diversity distribution patterns of freshwater vertebrates and invertebrates in the Napo Basin, as a tool for present and future management and conservation efforts. Also, we assessed the spatial congruence of the diversity patterns observed between aquatic vertebrates and invertebrates. For this, we compiled occurrence records for 481 freshwater vertebrate species (amphibians, birds, mammals, reptiles, and fish), and 54 invertebrate …


Examining The Relevancy And Utility Of The American Fisheries Society Certification Program To Prepare Future Fisheries Professionals, Mark A. Kaemingk, Ron Essig, Steve L. Mcmullin, Craig Bonds, Robin L. Debruyne, Christopher A. Myrick, Quinton E. Phelps, Trent M. Sutton, James R. Triplett Aug 2016

Examining The Relevancy And Utility Of The American Fisheries Society Certification Program To Prepare Future Fisheries Professionals, Mark A. Kaemingk, Ron Essig, Steve L. Mcmullin, Craig Bonds, Robin L. Debruyne, Christopher A. Myrick, Quinton E. Phelps, Trent M. Sutton, James R. Triplett

School of Natural Resources: Faculty Publications

Fisheries science is a diverse field that requires individuals to be knowledgeable in many disciplines in addition to fisheries (e.g., economics, sociology, political science, chemistry; Kelso and Murphy 1988). This challenges students attempting to enter a career in fisheries, as well as academic institutions and eventual employers, to develop both depth and breadth of knowledge needed to succeed in the profession (Oglesby and Krueger 1989). The preparedness and competency of young professionals entering the workforce has long been a problem (Stauffer and McMullin 2009). Several constraints and ongoing challenges facing the profession have continued to magnify these issues over time …


Are We Preparing The Next Generation Of Fisheries Professionals To Succeed In Their Careers?: A Survey Of Afs Members, Steve L. Mcmullin, Vic Dicenzo, Ron Essig, Craig Bonds, Robin L. Debruyne, Mark A. Kaemingk, Martha Mather, Christopher A. Myrick, Quinton E. Phelps, Trent M. Sutton, James R. Triplett Aug 2016

Are We Preparing The Next Generation Of Fisheries Professionals To Succeed In Their Careers?: A Survey Of Afs Members, Steve L. Mcmullin, Vic Dicenzo, Ron Essig, Craig Bonds, Robin L. Debruyne, Mark A. Kaemingk, Martha Mather, Christopher A. Myrick, Quinton E. Phelps, Trent M. Sutton, James R. Triplett

School of Natural Resources: Faculty Publications

Natural resource professionals have frequently criticized universities for poorly preparing graduates to succeed in their jobs. We surveyed members of the American Fisheries Society to determine which job skills and knowledge of academic topics employers, students, and university faculty members deemed most important to early-career success of fisheries professionals. Respondents also rated proficiency of recently hired, entry-level professionals (employers) on how well their programs prepared them for career success (students and faculty) in those same job skills and academic topics. Critical thinking and written and oral communication skills topped the list of important skills and academic topics. Employers perceived recent …


Survival And Cause-Specific Mortality Of Female Eastern Wild Turkeys In Two Frequently-Burned Longleaf Pine Savannas, Andrew R. Little, John F. Benson, Michael J. Chamberlain, L. Mike Conner, Robert J. Warren Jun 2016

Survival And Cause-Specific Mortality Of Female Eastern Wild Turkeys In Two Frequently-Burned Longleaf Pine Savannas, Andrew R. Little, John F. Benson, Michael J. Chamberlain, L. Mike Conner, Robert J. Warren

School of Natural Resources: Faculty Publications

Longleaf pine savannas have declined throughout the southeastern United States due to land-use change. Fortunately, natural resource professionals are currently restoring these ecologically and economically important savannas. Although efforts are underway to restore longleaf pine savannas, little information exists on female eastern wild turkey Meleagris gallopavo silvestris population dynamics in these systems. Therefore, we evaluated survival and cause-specific mortality of female eastern wild turkeys in two longleaf pine savannas in southwestern Georgia. We radio-marked 126 female wild turkeys during 2010–2013 and monitored their survival; 66 (52.4%) radio-marked females died during the study. We estimated causes of death for 37 mortality …


Carbon And Energy Fluxes In Cropland Ecosystems: A Model-Data Comparison, Erandathie Lokupitiya, A. S. Denning, K. Schaefer, D. Ricciuto, R. Anderson, M. A. Arain, Colorado State University, A. G. Barr, G. Chen, J. M. Chen, P. Ciais, D. R. Cook, M. Dietze, M. El Maayar, M. Fischer, University Of Alberta, D. Hollinger, C. Izaurralde, A. Jain, C. Kucharik, Z. Li, S. Liu, L. Li, R. Matamala, P. Peylin, D. Price, S. W. Running, A. Sahoo, M. Sprintsin, Andrew Suyker, H. Tian, C. Tonitto, M. Torn, Hans Verbeeck, Shashi Verma, Y. Xue Jun 2016

Carbon And Energy Fluxes In Cropland Ecosystems: A Model-Data Comparison, Erandathie Lokupitiya, A. S. Denning, K. Schaefer, D. Ricciuto, R. Anderson, M. A. Arain, Colorado State University, A. G. Barr, G. Chen, J. M. Chen, P. Ciais, D. R. Cook, M. Dietze, M. El Maayar, M. Fischer, University Of Alberta, D. Hollinger, C. Izaurralde, A. Jain, C. Kucharik, Z. Li, S. Liu, L. Li, R. Matamala, P. Peylin, D. Price, S. W. Running, A. Sahoo, M. Sprintsin, Andrew Suyker, H. Tian, C. Tonitto, M. Torn, Hans Verbeeck, Shashi Verma, Y. Xue

School of Natural Resources: Faculty Publications

Croplands are highly productive ecosystems that contribute to land–atmosphere exchange of carbon, energy, and water during their short growing seasons. We evaluated and compared net ecosystem exchange (NEE), latent heat flux (LE), and sensible heat flux (H) simulated by a suite of ecosystem models at five agricultural eddy covariance flux tower sites in the central United States as part of the North American Carbon Program Site Synthesis project. Most of the models overestimated H and underestimated LE during the growing season, leading to overall higher Bowen ratios compared to the observations. Most models systematically under predicted NEE, especially at rain-fed …


Habitat Selection Of Wild Turkeys In Burned Longleaf Pine Savannas, Andrew R. Little, Michael J. Chamberlain, L. Mike Conner, Robert J. Warren Jun 2016

Habitat Selection Of Wild Turkeys In Burned Longleaf Pine Savannas, Andrew R. Little, Michael J. Chamberlain, L. Mike Conner, Robert J. Warren

School of Natural Resources: Faculty Publications

Frequent prescribed fire (≤3 yr) and selective harvest of off-site hardwoods are the primary restoration and management tools for pine (Pinus spp.) savannas in the southeastern United States. However, a knowledge gap exists in our understanding of eastern wild turkey (Meleagris gallopavo silvestris) habitat selection in longleaf pine savannas and research is warranted to direct our future management decisions. Therefore, we investigated habitat selection of female turkeys in 2 longleaf pine savanna systems managed by frequent fire in southwestern Georgia during 2011–2013. We observed differential habitat selection across 2 scales (study area and seasonal area of use) …


Submerged Area Of Typical Torrential Flood And Debris-Flow Disasters In Mengzong Gully, China, Ai-Di Huo, Wen-Ke Guan, Jian Dang, Tian-Zhong Wu, Hainiken Shantai, Wei Wang, Michael W. Van Liew May 2016

Submerged Area Of Typical Torrential Flood And Debris-Flow Disasters In Mengzong Gully, China, Ai-Di Huo, Wen-Ke Guan, Jian Dang, Tian-Zhong Wu, Hainiken Shantai, Wei Wang, Michael W. Van Liew

School of Natural Resources: Faculty Publications

The torrential flooding and debris flow disasters associated with global climate change pose not only serious threat to individual lives and property, but also impact economic development. Accurately simulating flood scenarios can help to reduce the losses caused by torrential flooding and debris flow by making early warning, evacuation planning, and risk analysis possible. In this study, HEC-RAS software and HEC-GeoRAS module were employed in GIS (geographic information system) to simulate the flood overtopping in the Mengzong Gully of Batang River in flood scenarios occurring once in 20, 50, and 100 years, respectively. The simulated floods provided valuable information including …


Fluctuating Survival Selection Explains Variation In Avian Group Size, Charles R. Brown, Mary Bomberger Brown, Erin A. Roche, Valerie A. O'Brien, Catherine E. Page May 2016

Fluctuating Survival Selection Explains Variation In Avian Group Size, Charles R. Brown, Mary Bomberger Brown, Erin A. Roche, Valerie A. O'Brien, Catherine E. Page

School of Natural Resources: Faculty Publications

Most animal groups vary extensively in size. Because individuals in certain sizes of groups often have higher apparent fitness than those in other groups, why wide group size variation persists in most populations remains unexplained. We used a 30-y mark– recapture study of colonially breeding cliff swallows (Petrochelidon pyrrhonota) to show that the survival advantages of different colony sizes fluctuated among years. Colony size was under both stabilizing and directional selection in different years, and reversals in the sign of directional selection regularly occurred. Directional selection was predicted in part by drought conditions: birds in larger colonies tended …


Eastern Wild Turkey Nest Site Selection In Two Frequently Burned Pine Savannas, Andrew R. Little, Nathan P. Nibbelink, Michael J. Chamberlain, L. Mike Conner, Robert J. Warren Apr 2016

Eastern Wild Turkey Nest Site Selection In Two Frequently Burned Pine Savannas, Andrew R. Little, Nathan P. Nibbelink, Michael J. Chamberlain, L. Mike Conner, Robert J. Warren

School of Natural Resources: Faculty Publications

Introduction: Reproductive success is a critical factor affecting avian demographics and can be influenced by many factors including nesting chronology, predation risk, and fine-scale nest site selection.

Methods: We modeled the relative influences of habitat-related covariates at six spatial scales (nest site: 15-, 40-, 80-, 120-, 160-, and 200-m radii) on Eastern wild turkey (Meleagris gallopavo silvestris) nest site selection in two pine savannas managed by frequent prescribed fire (≤3 years) in southwestern Georgia during 2011–2013.

Results: Nest site (15-m scale) habitat metrics (mean visual obstruction [cm] and canopy closure [%]) had the greatest influence on nest site …


Does Predation Influence The Seasonal And Diel Timing Of Moose Calving In Central Ontario, Canada?, Brent R. Patterson, Kenneth J. Mills, Kevin R. Middel, John F. Benson, Martyn E. Obbard Apr 2016

Does Predation Influence The Seasonal And Diel Timing Of Moose Calving In Central Ontario, Canada?, Brent R. Patterson, Kenneth J. Mills, Kevin R. Middel, John F. Benson, Martyn E. Obbard

School of Natural Resources: Faculty Publications

Birth synchrony is well documented among ungulates and is hypothesised to maximize neonate survival, either by minimizing the risk of predation through predator swamping or by synchronising birthing with increased seasonal food availability. We used encapsulated vaginal implant transmitters to locate and capture neonatal moose calves and document the seasonal and diel timing of parturition in two adjacent study areas with different predation pressure in central Ontario, Canada. We tested the hypothesis that predation promotes earlier and more synchronous birth of moose calves. Across both areas, proportionately more births occurred during the afternoon and fewer than expected occurred overnight. Mean …


Acoustic Detection Reveals Fine-Scale Distributions Of Myotis Lucifugus, Myotis Septentrionalis, And Perimyotis Subflavus In Eastern Nebraska, Jeremy A. White, Cliff Lemen, Patricia Freeman Apr 2016

Acoustic Detection Reveals Fine-Scale Distributions Of Myotis Lucifugus, Myotis Septentrionalis, And Perimyotis Subflavus In Eastern Nebraska, Jeremy A. White, Cliff Lemen, Patricia Freeman

School of Natural Resources: Faculty Publications

ABSTRACT.—Before white-nose syndrome arrives in Nebraska, it is important to document the preexposure distributions of cave bats in the state. We examined the distributions of Myotis lucifugus (little brown myotis), Myotis septentrionalis (northern long-eared myotis), and Perimyotis subflavus (tri-colored bat) in eastern Nebraska by setting acoustic detectors for a single night at 105 sites in wooded habitats during summers of 2012 and 2014. We compared 2 methods of determining presence at each site. Results of our analyses are fine-scale distributional maps for these bats and some range extensions from published records. Results for M. septentrionalis and P. subflavus are largely …


Using Cosmic-Ray Neutron Probes To Monitor Landscape Scale Soil Water Content In Mixed Land Use Agricultural Systems, Trenton E. Franz, Ammar Wahbi, Mariette Vreugdenhil, Georg Weltin, Lee Hang, Markus Oismueller, Peter Strauss, Gerd Dercon, Darin Desilets Feb 2016

Using Cosmic-Ray Neutron Probes To Monitor Landscape Scale Soil Water Content In Mixed Land Use Agricultural Systems, Trenton E. Franz, Ammar Wahbi, Mariette Vreugdenhil, Georg Weltin, Lee Hang, Markus Oismueller, Peter Strauss, Gerd Dercon, Darin Desilets

School of Natural Resources: Faculty Publications

With an ever-increasing demand for natural resources and the societal need to understand and predict natural disasters, soil water content (SWC) observations remain a critical variable to monitor in order to optimally allocate resources, establish early warning systems, and improve weather forecasts.However, routine agricultural production practices of soil cultivation, planting, and harvest make the operation andmaintenance of direct contact point sensors for long-termmonitoring challenging. In this work, we explore the use of the newly established Cosmic-Ray Neutron Probe (CRNP) and method to monitor landscape average SWC in a mixed agricultural land use systemin northeastAustria.Thecalibrated CRNP landscape SWC values compare well …


The Sensitivity Of Carbon Exchanges In Great Plains Grasslands To Precipitation Variability, M.D. Petrie, N. A. Brunsell, R. Vargas, Scott L. Collins, L.B. Flanagan, N.P. Hanan, M.E. Litvak, A. E. Suyker Feb 2016

The Sensitivity Of Carbon Exchanges In Great Plains Grasslands To Precipitation Variability, M.D. Petrie, N. A. Brunsell, R. Vargas, Scott L. Collins, L.B. Flanagan, N.P. Hanan, M.E. Litvak, A. E. Suyker

School of Natural Resources: Faculty Publications

In the Great Plains, grassland carbon dynamics differ across broad gradients of precipitation and temperature, yet finer-scale variation in these variables may also affect grassland processes. Despite the importance of grasslands, there is little information on how fine-scale relationships compare between them regionally. We compared grassland C exchanges, energy partitioning and precipitation variability in eight sites in the eastern and western Great Plains using eddy covariance and meteorological data. During our study, both eastern and western grasslands varied between an average net carbon sink and a net source. Eastern grasslands had a moderate vapor pressure deficit (VPD = 0.95 kPa) …


Closing The Water Balance With Cosmic-Ray Soil Moisture Measurements And Assessing Their Relation To Evapotranspiration In Two Semiarid Watersheds, A. P. Schreiner-Mcgraw, E. R. Vivoni, G. Mascaro, Trenton E. Franz Jan 2016

Closing The Water Balance With Cosmic-Ray Soil Moisture Measurements And Assessing Their Relation To Evapotranspiration In Two Semiarid Watersheds, A. P. Schreiner-Mcgraw, E. R. Vivoni, G. Mascaro, Trenton E. Franz

School of Natural Resources: Faculty Publications

Soil moisture dynamics reflect the complex interactions of meteorological conditions with soil, vegetation and terrain properties. In this study, intermediate-scale soil moisture estimates from the cosmic-ray neutron sensing (CRNS) method are evaluated for two semiarid ecosystems in the southwestern United States: a mesquite savanna at the Santa Rita Experimental Range (SRER) and a mixed shrubland at the Jornada Experimental Range (JER). Evaluations of the CRNS method are performed for small watersheds instrumented with a distributed sensor network consisting of soil moisture sensor profiles, an eddy covariance tower, and runoff flumes used to close the water balance. We found a very …


The Grand Ethiopian Renaissance Dam: Source Of Cooperation Or Contention?, Meron Teferi Taye, Tsegaye Tadesse, Gabriel B. Senay, Paul Block Jan 2016

The Grand Ethiopian Renaissance Dam: Source Of Cooperation Or Contention?, Meron Teferi Taye, Tsegaye Tadesse, Gabriel B. Senay, Paul Block

School of Natural Resources: Faculty Publications

This paper discusses the challenges and benefits of the Grand Ethiopian Renaissance Dam (GERD), which is under construction and expected to be operational on the Blue Nile River in Ethiopia in a few years. Like many large-scale projects on transboundary rivers, the GERD has been criticized for potentially jeopardizing downstream water security and livelihoods through upstream unilateral decision making. In spite of the contentious nature of the project, the authors argue that this project can provide substantial benefits for regional development. The GERD, like any major river infrastructure project, will undeniably bring about social, environmental, and economic change, and in …


Temporal Variability In Large Grazer Space Use In An Experimental Landscape, Edward J. Raynor, Anthony Joren, Adam Skibbe, Mark Sowers, John M. Briggs, Angela N. Laws, Douglas Goodin Jan 2016

Temporal Variability In Large Grazer Space Use In An Experimental Landscape, Edward J. Raynor, Anthony Joren, Adam Skibbe, Mark Sowers, John M. Briggs, Angela N. Laws, Douglas Goodin

School of Natural Resources: Faculty Publications

Land use, climate change, and their interaction each have great potential to affect grazing systems. With anticipated more frequent and extensive future drought, a more complete understanding of the mechanisms that determine large grazer landscape-level distribution under varying climatic conditions is integral to ecosystem management. Using an experimental setting with contrasting fire treatments, we describe the inter-annual variability of the effect of landscape topography and disturbance from prescribed spring fire on large grazer space use in years of variable resource availability. Using GPS telemetry, we investigated space use of plains bison (Bison bison bison) as they moved among watersheds managed …


Narrowing The Agronomic Yield Gaps Of Maize By Improved Soil, Cultivar, And Agricultural Management Practices In Different Climate Zones Of Northeast China, Zhijuan Liu, Xiaoguang Yang, Xiaomao Lin, Kenneth Hubbard, Shuo Lv, Jing Wang Jan 2016

Narrowing The Agronomic Yield Gaps Of Maize By Improved Soil, Cultivar, And Agricultural Management Practices In Different Climate Zones Of Northeast China, Zhijuan Liu, Xiaoguang Yang, Xiaomao Lin, Kenneth Hubbard, Shuo Lv, Jing Wang

School of Natural Resources: Faculty Publications

Northeast China (NEC) is one of the major agricultural production areas in China, producing about 30% of China’s total maize output. In the past five decades, maize yields in NEC increased rapidly. However, farmer yields still have potential to be increased. Therefore, it is important to quantify the impacts of agronomic factors, including soil physical properties, cultivar selections, and management practices on yield gaps of maize under the changing climate in NEC in order to provide reliable recommendations to narrow down the yield gaps. In this study, the Agricultural Production Systems Simulator (APSIM)-Maize model was used to separate the contributions …


To Exclose Nests Or Not: Structured Decision Making For The Conservation Of A Threatened Species, Jonathan B. Cohen, Anne Hecht, Kelly F. Robinson, Erik E. Osnas, Andrew Tyre, Christina Davis, Alison Kocek, Brooke Maslo, Scott M. Melvin Jan 2016

To Exclose Nests Or Not: Structured Decision Making For The Conservation Of A Threatened Species, Jonathan B. Cohen, Anne Hecht, Kelly F. Robinson, Erik E. Osnas, Andrew Tyre, Christina Davis, Alison Kocek, Brooke Maslo, Scott M. Melvin

School of Natural Resources: Faculty Publications

Decisions regarding endangered species recovery often face sparse data and multiple sources of uncertainty about the effects of management. Structured decision making (SDM) provides a framework for assembling knowledge and expert opinion and evaluating the tradeoffs between different objectives while formally incorporating uncertainty. The Atlantic Coast piping plover provides an illustrative case for the utility of SDM in endangered species management because its population growth is simple to model, most populations are monitored, decision alternatives are well defined, and many managers are open to recovery recommendations. We built a model to evaluate the decision to use nest exclosures to protect …


Convergent Evolution In Social Swallows (Aves: Hirundinidae), Allison E. Johnson, Jonathan S. Mitchell, Mary B. Brown Jan 2016

Convergent Evolution In Social Swallows (Aves: Hirundinidae), Allison E. Johnson, Jonathan S. Mitchell, Mary B. Brown

School of Natural Resources: Faculty Publications

Behavioral shifts can initiate morphological evolution by pushing lineages into new adaptive zones. This has primarily been examined in ecological behaviors, such as foraging, but social behaviors may also alter morphology. Swallows and martins (Hirundinidae) are aerial insectivores that exhibit a range of social behaviors, from solitary to colonial breeding and foraging. Using a well-resolved phylogenetic tree, a database of social behaviors, and morphological measurements, we ask how shifts from solitary to social breeding and foraging have affected morphological evolution in the Hirundinidae. Using a threshold model of discrete state evolution, we find that shifts in both breeding and foraging …


Current Topics In Avian Conservation Genetics With Special Reference To The Southwestern Willow Flycatcher, R.M. Zink Jan 2016

Current Topics In Avian Conservation Genetics With Special Reference To The Southwestern Willow Flycatcher, R.M. Zink

School of Natural Resources: Faculty Publications

No abstract provided.


Quantification And Mapping Of Surface Residue Cover For Maize And Soybean Fields In South Central Nebraska, Vivek Sharma, Suat Irmak, Ayse Kilic, Vasudha Sharma, John E. Gilley, George Meyer, Stevan Z. Knezevic, D. B. Marx Jan 2016

Quantification And Mapping Of Surface Residue Cover For Maize And Soybean Fields In South Central Nebraska, Vivek Sharma, Suat Irmak, Ayse Kilic, Vasudha Sharma, John E. Gilley, George Meyer, Stevan Z. Knezevic, D. B. Marx

School of Natural Resources: Faculty Publications

The area cultivated under conservation tillage practices such as no-till and minimal tillage has recently increased in Midwestern states, including Nebraska. This increase, consequently, resulted in changes in some of the impacts of cropping systems on soil, such as enhancing soil and water quality, improving soil structure and infiltration, increasing water use efficiency, and promoting carbon sequestration. However, there are no methods currently available to quantify the percent crop residue cover (CRC) and the area under conservation tillage for maize and soybean at large scales on a continuous basis. This research used Landsat-7 (ETM+) and Landsat-8 (OLI) satellite data to …


Sensitivity Of Evapotranspiration Retrievals From The Metric Processing Algorithm To Improved Radiometric Resolution Of Landsat 8 Thermal Data And To Calibration Bias In Landsat 7 And 8 Surface Temperature, Ayse Kilic, Richard G. Allen, Ricardo Trezza, Ian Ratcliffe, Baburao Kamble, Clarence W. Robison, Doruk Ozturk Jan 2016

Sensitivity Of Evapotranspiration Retrievals From The Metric Processing Algorithm To Improved Radiometric Resolution Of Landsat 8 Thermal Data And To Calibration Bias In Landsat 7 And 8 Surface Temperature, Ayse Kilic, Richard G. Allen, Ricardo Trezza, Ian Ratcliffe, Baburao Kamble, Clarence W. Robison, Doruk Ozturk

School of Natural Resources: Faculty Publications

We made an assessment on the use of 12-bit resolution of Landsat 8 (L8) on evapotranspiration (ET) retrievals via the METRIC process as compared to using 8-bit resolution imagery of previous Landsat missions. METRIC (Mapping Evapotranspiration at high Resolution using Internalized Calibration) is an ET retrieval system commonly used in water and water rights management where the surface energy balance process is coupled with an extreme- end point calibration process to remove most impacts of systematic bias in remotely sensed inputs. We degraded L8 thermal images by grouping sequential digital numbers to reduce the apparent numerical resolution and then recomputed …


Data Descriptor: Remotely Sensed High Resolution Irrigated Area Mapping In India For 2000 To 2015, Anukesh Krishnankutty Ambika, Brian D. Wardlow, Vimal Mishra Jan 2016

Data Descriptor: Remotely Sensed High Resolution Irrigated Area Mapping In India For 2000 To 2015, Anukesh Krishnankutty Ambika, Brian D. Wardlow, Vimal Mishra

School of Natural Resources: Faculty Publications

India is among the countries that uses a significant fraction of available water for irrigation. Irrigated area in India has increased substantially after the Green revolution and both surface and groundwater have been extensively used. Under warming climate projections, irrigation frequency may increase leading to increased irrigation water demands. Water resources planning and management in agriculture need spatially-explicit irrigated area information for different crops and different crop growing seasons. However, annual, high-resolution irrigated area maps for India for an extended historical record that can be used for water resources planning and management are unavailable. Using 250m normalized difference vegetation index …


A Spatiotemporal Analysis Of Midwest Us Temperature And Precipitation Trends During The Growing Season From 1980 To 2013, Shuwei Dai, Martha Shulski, Kenneth Hubbard, Eugene S. Takle Jan 2016

A Spatiotemporal Analysis Of Midwest Us Temperature And Precipitation Trends During The Growing Season From 1980 To 2013, Shuwei Dai, Martha Shulski, Kenneth Hubbard, Eugene S. Takle

School of Natural Resources: Faculty Publications

Since late 1970s, climate warming has been widely recognized. In the Midwest, farmers cannot rely on the normal calendar anymore, and it has become critically necessary to evaluate the most recent climate trends relative to growing season in order to conduct adaptation efforts for agriculture. Based on the homogenized historical monthly temperature and precipitation records during the period of 1980–2013 from 302 observing stations in the 12 Midwestern US states, we investigate the climate trends on four timescales: monthly, early growing season, late growing season, and the entire growing season. The climate metrics include maximum temperature, minimum temperature, average temperature, …


2016 Interior Least Tern And Piping Plover Monitoring, Research, Management, And Outreach Report For The Lower Platte River, Nebraska, Mary Bomberger Brown, Lauren R. Dinan Jan 2016

2016 Interior Least Tern And Piping Plover Monitoring, Research, Management, And Outreach Report For The Lower Platte River, Nebraska, Mary Bomberger Brown, Lauren R. Dinan

School of Natural Resources: Faculty Publications

This document reports on our monitoring, research, management, and outreach activities during the past 12 months (2015 – 2016). We prepared it to inform our partners, cooperating agencies, funding sources, and other interested parties of our activities and to provide a preliminary summary of our results.

The data, data analyses, results, summaries, and interpretations found in this document are not final and should be considered as such when being cited or referred to in documents, reports, proposals, or presentations. Please contact us before using any of this material and for additional information that may be available.

In an effort to …


Impact Perceptions And Acceptance Capacity Toward Piping Plovers Charadrius Melodus Among Visitors On A Public Beach In Nebraska, Usa, Joel G. Jorgensen, Mary Bomberger Brown Jan 2016

Impact Perceptions And Acceptance Capacity Toward Piping Plovers Charadrius Melodus Among Visitors On A Public Beach In Nebraska, Usa, Joel G. Jorgensen, Mary Bomberger Brown

School of Natural Resources: Faculty Publications

On an increasingly crowded planet, shorebirds and humans are frequently found sharing the same ecosystems. This development requires that the managers of these human-wildlife ecosystems address human dimensions challenges in addition to those associated with species biology. To better understand such challenges, we evaluated impact perceptions and overall acceptance capacity in visitors on public beaches of Lake McConaughy, Nebraska, USA towards a federally- protected shorebird, the Piping Plover Charadrius melodus. Overall acceptance capacity for these birds was relatively high and perceptions of inconvenience caused by the presence of the birds were low. However, acceptance capacity and impact perceptions varied …


Informative Spectral Bands For Remote Green Lai Estimation In C3 And C4 Crops, Oz Kira, Anthony L. Nguy-Robertson, Timothy J. Arkebauer, Raphael Linker, Anatoly A. Gitelson Jan 2016

Informative Spectral Bands For Remote Green Lai Estimation In C3 And C4 Crops, Oz Kira, Anthony L. Nguy-Robertson, Timothy J. Arkebauer, Raphael Linker, Anatoly A. Gitelson

School of Natural Resources: Faculty Publications

Green leaf area index (LAI) provides insight into the productivity, physiological and phenological status of vegetation. Measurement of spectral reflectance offers a fast and nondestructive estimation of green LAI. A number of methods have been used for the estimation of green LAI; however, the specific spectral bands employed varied widely among the methods and data used. Our objectives were (i) to find informative spectral bands retained in three types of methods, neural network (NN), partial least squares (PLS) regression and vegetation indices (VI), for estimating green LAI in maize (a C4 species) and soybean (a C3 species); (ii) to assess …


Potential Direct And Indirect Effects Of Climate Change On A Shallow Natural Lake Fish Assemblage, Jason J. Breeggemann, Mark A. Kaemingk, Timothy J. Debates, Craig P. Paukert, Jacob R. Krause, Alexander P. Letvin, Tanner M. Stevens, David W. Willis, Steven R. Chipps Jan 2016

Potential Direct And Indirect Effects Of Climate Change On A Shallow Natural Lake Fish Assemblage, Jason J. Breeggemann, Mark A. Kaemingk, Timothy J. Debates, Craig P. Paukert, Jacob R. Krause, Alexander P. Letvin, Tanner M. Stevens, David W. Willis, Steven R. Chipps

School of Natural Resources: Faculty Publications

Much uncertainty exists around how fish communities in shallow lakes will respond to climate change. In this study, we modelled the effects of increased water temperatures on consumption and growth rates of two piscivores (northern pike [Esox lucius] and largemouth bass [Micropterus salmoides]) and examined relative effects of consumption by these predators on two prey species (bluegill [Lepomis macrochirus] and yellow perch [Perca flavescens]). Bioenergetics models were used to simulate the effects of climate change on growth and food consumption using predicted 2040 and 2060 temperatures in a shallow Nebraska Sandhill lake, …


A Framework For Understanding The Characteristics Of Complexity In Biology, Joseph Dauer, Jenny Dauer Jan 2016

A Framework For Understanding The Characteristics Of Complexity In Biology, Joseph Dauer, Jenny Dauer

School of Natural Resources: Faculty Publications

Understanding the functioning of natural systems is not easy, although there is general agreement that understanding complex systems is an important goal for science education. Defining what makes a natural system complex will assist in identifying gaps in research on student reasoning about systems. The goal of this commentary is to propose a framework that explicitly defines the ways in which biological systems are complex and to discuss the potential relevance of these complexity dimensions to conducting research on student reasoning about complexity in biology classrooms. We use an engineering framework for dimensions of complexity and discuss how this framework …