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School of Natural Resources: Faculty Publications

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Articles 661 - 690 of 1586

Full-Text Articles in Physical Sciences and Mathematics

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 …

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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) …

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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 …

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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 …

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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 …

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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 …

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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 …

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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 …

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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.

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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 …

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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 …

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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 …

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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, …

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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 …

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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 …

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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, …

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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 …

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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 Jan 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 …

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Impacts Of Human Hunting On Spatial Behavior Of White-Tailed Deer (Odocoileus Virginianus), Sierra A. Marantz, Jed A. Long, Stephen L. Webb, Kenneth L. Gee, Andrew R. Little, Stephen Demarais Jan 2016

Impacts Of Human Hunting On Spatial Behavior Of White-Tailed Deer (Odocoileus Virginianus), Sierra A. Marantz, Jed A. Long, Stephen L. Webb, Kenneth L. Gee, Andrew R. Little, Stephen Demarais

School of Natural Resources: Faculty Publications

Predators can influence populations through top-down effects, but most large predators have been extirpated from the range of white-tailed deer (Odocoileus virginianus (Zimmermann, 1780)). Hunters have filled this predatory role, but also can indirectly influence prey species. Indirect behavioral responses can include altered resource selection, space use, or movement. Herein, we developed a controlled study that contained both temporal and spatial risk levels to assess how deer behavior changes relative to temporal periods of risk. Total distance travelled and microrange area over 2-day periods were used to determine the general effects of hunting season on deer spatial behavior. Generally, distance …

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Monitoring Grassland Seasonal Carbon Dynamics, By Integrating Modis Ndvi, Proximal Optical Sampling, And Eddy Covariance Measurements, Enrica Nestola, Carlo Calfapietra, Craig A. Emmerton, Christopher Y. S. Wong, Donnette R. Thayer, John A. Gamon Jan 2016

Monitoring Grassland Seasonal Carbon Dynamics, By Integrating Modis Ndvi, Proximal Optical Sampling, And Eddy Covariance Measurements, Enrica Nestola, Carlo Calfapietra, Craig A. Emmerton, Christopher Y. S. Wong, Donnette R. Thayer, John A. Gamon

School of Natural Resources: Faculty Publications

This study evaluated the seasonal productivity of a prairie grassland (Mattheis Ranch, in Alberta, Canada) using a combination of remote sensing, eddy covariance, and field sampling collected in 2012–2013. A primary objective was to evaluate different ways of parameterizing the light-use efficiency (LUE) model for assessing net ecosystem fluxes at two sites with contrasting productivity. Three variations on the NDVI (Normalized Difference Vegetation Index), differing by formula and footprint, were derived: (1) a narrow-band NDVI (NDVI680,800, derived from mobile field spectrometer readings); (2) a broad-band proxy NDVI (derived from an automated optical phenology station consisting of broad-band radiometers); and (3) …

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Integrated Analysis Of Productivity And Biodiversity In A Southern Alberta Prairie, Ran Wang, John A. Gamon, Craig A. Emmerton, Haitao Li, Enrica Nestola, Gilberto Z. Pastorello, Olaf Menzer Jan 2016

Integrated Analysis Of Productivity And Biodiversity In A Southern Alberta Prairie, Ran Wang, John A. Gamon, Craig A. Emmerton, Haitao Li, Enrica Nestola, Gilberto Z. Pastorello, Olaf Menzer

School of Natural Resources: Faculty Publications

Grasslands play important roles in ecosystem production and support a large farming and grazing industry. An accurate and efficient way is needed to estimate grassland health and production for monitoring and adjusting management to get sustainable products and other ecosystem services. Previous studies of grasslands have shown varying relationships between productivity and biodiversity, with most showing either a positive or a hump-shaped relationship where productivity peaks at intermediate diversity. In this study, we used airborne imaging spectrometry combined with ground sampling and eddy covariance measurements to estimate the spatial pattern of production and biodiversity for two sites of contrasting productivity …

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Seasonal Variation In The Ndvi–Species Richness Relationship In A Prairie Grassland Experiment (Cedar Creek), Ran Wang, John A. Gamon, Rebecca A. Montgomery, Philip A. Townsend, Arthur I. Zygielbaum, Keren Bitan, David Tilman, Jeannine Cavender-Bares Jan 2016

Seasonal Variation In The Ndvi–Species Richness Relationship In A Prairie Grassland Experiment (Cedar Creek), Ran Wang, John A. Gamon, Rebecca A. Montgomery, Philip A. Townsend, Arthur I. Zygielbaum, Keren Bitan, David Tilman, Jeannine Cavender-Bares

School of Natural Resources: Faculty Publications

Species richness generally promotes ecosystem productivity, although the shape of the relationship varies and remains the subject of debate. One reason for this uncertainty lies in the multitude of methodological approaches to sampling biodiversity and productivity, some of which can be subjective. Remote sensing offers new, objective ways of assessing productivity and biodiversity. In this study, we tested the species richness–productivity relationship using a common remote sensing index, the Normalized Difference Vegetation Index (NDVI), as a measure of productivity in experimental prairie grassland plots (Cedar Creek). Our study spanned a growing season (May to October, 2014) to evaluate dynamic changes …

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Interannual Variability In Dry Mixed-Grass Prairie Yield: A Comparison Of Modis, Spot, And Field Measurements, Donald C. Wehlage, John A. Gamon, Donnette Thayer, David V. Hildebrand Jan 2016

Interannual Variability In Dry Mixed-Grass Prairie Yield: A Comparison Of Modis, Spot, And Field Measurements, Donald C. Wehlage, John A. Gamon, Donnette Thayer, David V. Hildebrand

School of Natural Resources: Faculty Publications

Remote sensing is often used to assess rangeland condition and biophysical parameters across large areas. In particular, the relationship between the Normalized Difference Vegetation Index (NDVI) and above-ground biomass can be used to assess rangeland primary productivity (seasonal carbon gain or above-ground biomass “yield”). We evaluated the NDVI–yield relationship for a southern Alberta prairie rangeland, using seasonal trends in NDVI and biomass during the 2009 and 2010 growing seasons, two years with contrasting rainfall regimes. The study compared harvested biomass and NDVI from field spectrometry to NDVI from three satellite platforms: the Aqua and Terra Moderate Resolution Imaging Spectroradiometer (MODIS) …

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Caught Between A Rock And A Hard Mineral Encrustation: Long-Lived Aquatic Insects Accumulate Calcium Carbonate Deposits In A Montane Desert Stream, Eric K. Moody, Jessica R. Corman, Michael T. Bogan Jan 2016

Caught Between A Rock And A Hard Mineral Encrustation: Long-Lived Aquatic Insects Accumulate Calcium Carbonate Deposits In A Montane Desert Stream, Eric K. Moody, Jessica R. Corman, Michael T. Bogan

School of Natural Resources: Faculty Publications

Aquatic ecosystems overlying regions of limestone bedrock can feature active deposition of calcium carbonate in the form of travertine or tufa. Although most travertine deposits form a cement-like layer on stream substrates, mineral deposits can also form on benthic invertebrates. However, little is known about which taxa may be prone to calcium carbonate encrustation and which life history traits may make taxa more susceptible to becoming encrusted. Here we report the presence of calcium carbonate deposits on live insects collected from a montane stream in the Madrean Sky Islands (Huachuca Mountains) of Arizona between 2011 and 2013. Life history differences …

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Avian Interactions With Renewable Energy Infrastructure: An Update, Jennifer A. Smith, James F. Dwyer Jan 2016

Avian Interactions With Renewable Energy Infrastructure: An Update, Jennifer A. Smith, James F. Dwyer

School of Natural Resources: Faculty Publications

Energy infrastructure is widespread worldwide. Renewable energy technologies, which are expanding their footprint on the landscape and their contribution to energy availability, represent a different kind of infrastructure from extractive energy technologies. Although renewable energy sources may offer a ‘greener alternative’ to traditional extractive energy sources, mounting evidence suggests that renewable energy infrastructure, and the transmission lines needed to convey energy from renewable energy facilities to users, may impact birds. Peer-reviewed literature historically has focused on the direct effects of electrocution and, to a lesser extent, collisions with overhead power systems, and on avian collisions at wind energy facilities, with …

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Estimation Of Energy Balance Components Over A Drip-Irrigated Olive Orchard Using Thermal And Multispectral Cameras Placed On A Helicopter-Based Unmanned Aerial Vehicle (Uav), Samuel Ortega-Farias, Samuel Ortega-Salazar, Tomas Poblete, Ayse Kilic, Richard Allen, Carlos Poblete-Echeverria, Luis Ahumada-Orellana, Mauricio Zuniga, Daniel Sepulveda Jan 2016

Estimation Of Energy Balance Components Over A Drip-Irrigated Olive Orchard Using Thermal And Multispectral Cameras Placed On A Helicopter-Based Unmanned Aerial Vehicle (Uav), Samuel Ortega-Farias, Samuel Ortega-Salazar, Tomas Poblete, Ayse Kilic, Richard Allen, Carlos Poblete-Echeverria, Luis Ahumada-Orellana, Mauricio Zuniga, Daniel Sepulveda

School of Natural Resources: Faculty Publications

A field experiment was carried out to implement a remote sensing energy balance (RSEB) algorithm for estimating the incoming solar radiation (Rsi), net radiation (Rn), sensible heat flux (H), soil heat flux (G) and latent heat flux (LE) over a drip-irrigated olive (cv. Arbequina) orchard located in the Pencahue Valley, Maule Region, Chile (35◦25'S; 71◦44'W; 90 m above sea level). For this study, a helicopter-based unmanned aerial vehicle (UAV) was equipped with multispectral and infrared thermal cameras to obtain simultaneously the normalized difference vegetation index (NDVI) and surface temperature (Tsurface) at very high resolution (6 cm …

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Coastal Development And Precipitation Drive Pathogen Flow From Land To Sea: Evidence From A Toxoplasma Gondii And Felid Host System, Elizabeth Vanwormer, Tim E. Carpenter, Purnendu Singh, Karen Shapiro, Wesley W. Wallender, Patricia A. Conrad, John L. Largier, Marco P. Maneta, Jonna A. K. Mazet Jan 2016

Coastal Development And Precipitation Drive Pathogen Flow From Land To Sea: Evidence From A Toxoplasma Gondii And Felid Host System, Elizabeth Vanwormer, Tim E. Carpenter, Purnendu Singh, Karen Shapiro, Wesley W. Wallender, Patricia A. Conrad, John L. Largier, Marco P. Maneta, Jonna A. K. Mazet

School of Natural Resources: Faculty Publications

Rapidly developing coastal regions face consequences of land use and climate change including flooding and increased sediment, nutrient, and chemical runoff, but these forces may also enhance pathogen runoff, which threatens human, animal, and ecosystem health. Using the zoonotic parasite Toxoplasma gondii in California, USA as a model for coastal pathogen pollution, we examine the spatial distribution of parasite runoff and the impacts of precipitation and development on projected pathogen delivery to the ocean. Oocysts, the extremely hardy free-living environmental stage of T. gondii shed in faeces of domestic and wild felids, are carried to the ocean by freshwater runoff. …

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Acute 𝛽-N-Methylamino-L-Alanine Toxicity In A Mouse Model, Maitham Ahmed Al-Sammak, Douglas G. Rogers, Kyle D. Hoagland Jan 2016

Acute 𝛽-N-Methylamino-L-Alanine Toxicity In A Mouse Model, Maitham Ahmed Al-Sammak, Douglas G. Rogers, Kyle D. Hoagland

School of Natural Resources: Faculty Publications

The cyanobacterial neurotoxin 𝛽-N-methylamino-L-alanine (BMAA) is considered to be an “excitotoxin,” and its suggested mechanism of action is killing neurons. Long-termexposure to L-BMAAis believed to lead to neurodegenerative diseases including Parkinson’s and Alzheimer’s diseases and amyotrophic lateral sclerosis (Lou Gehrig’s disease). Objectives of this study were to determine the presumptive median lethal dose (LD50), the Lowest-Observed-Adverse-Effect Level (LOAEL), and histopathologic lesions caused by the naturally occurring BMAA isomer, L-BMAA, in mice. Seventy NIH Swiss Outbred mice (35 male and 35 female) were used. Treatment group mice were injected intraperitoneally with 0.03, 0.3, 1, 2, and 3mg/g body weight L-BMAA, respectively, …

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Advanced Space Vehicle Design Taking Into Account Multidisciplinary Couplings And Mixed Epistemic/Aleatory Uncertainties, Mathieu Balesdent, Loic Brevault, Nathaniel B. Price, Sebastien Defoort, Rodolphe Le Riche, Nam-Ho Kim, Raphael T. Haftka, Nicolas Berend Jan 2016

Advanced Space Vehicle Design Taking Into Account Multidisciplinary Couplings And Mixed Epistemic/Aleatory Uncertainties, Mathieu Balesdent, Loic Brevault, Nathaniel B. Price, Sebastien Defoort, Rodolphe Le Riche, Nam-Ho Kim, Raphael T. Haftka, Nicolas Berend

School of Natural Resources: Faculty Publications

No abstract provided.

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Basic Forms And Orbit Spaces:A Diffeological Approach, Yael Karshon, Jordan Watts Jan 2016

Basic Forms And Orbit Spaces:A Diffeological Approach, Yael Karshon, Jordan Watts

School of Natural Resources: Faculty Publications

No abstract provided.

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