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Severe Drought Impacts Female Pheasant Physiology In Southwest Nebraska, Jessica A. Laskowski, Gwen C. Bachman, Joseph J. Fontaine Dec 2017

Severe Drought Impacts Female Pheasant Physiology In Southwest Nebraska, Jessica A. Laskowski, Gwen C. Bachman, Joseph J. Fontaine

The Prairie Naturalist

In 2012, Nebraska experienced one of the worst droughts since the 1930s, accompanied by abnormally high temperatures. We studied the impacts of the 2012 summer drought on female ring-necked pheasant (Phasianus colchicus) body condition and baseline and stress-induced corticosterone concentrations (CORT). We hypothesized that drought conditions would reduce pheasant body condition, increase chronic stress resulting in elevated baseline CORT levels, and down-regulate pheasant stress response to acute stressors, resulting in reduced stress-induced CORT concentrations. In southwestern Nebraska, we captured female pheasants in 2012 (pre-drought) and 2013 (post-drought). Pheasants had poorer body condition after the drought. Although female CORT measures were …


Capturing Species-Level Drought Responses In A Temperate Deciduous Forest Using Ratios Of Photochemical Reflectance Indices Between Sunlit And Shaded Canopies, Taehee Hwang, Hamed Gholizadeh, Daniel A. Sims, Kimberly A. Novick, Edward R. Brzostek, Richard P. Phillips, Daniel T. Roman, Scott M. Robeson, Abdullah F. Rahman Oct 2017

Capturing Species-Level Drought Responses In A Temperate Deciduous Forest Using Ratios Of Photochemical Reflectance Indices Between Sunlit And Shaded Canopies, Taehee Hwang, Hamed Gholizadeh, Daniel A. Sims, Kimberly A. Novick, Edward R. Brzostek, Richard P. Phillips, Daniel T. Roman, Scott M. Robeson, Abdullah F. Rahman

School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations

Highlights

  • We examine capability of spectral indices to capture isohydric/anisohydric behavior.

  • We used both in-situ spectral measurements and multi-angle MODIS images.

  • Only PRI could capture species-level drought responses.

  • This study presents a step forward to directly mapping emergent isohydricity.

Abstract

To classify trees along a spectrum of isohydric to anisohydric behavior is a promising new framework for identifying tree species' sensitivities to drought stress, directly related to the vulnerability of carbon uptake of terrestrial ecosystems with increased hydroclimate variability. Trees with isohydric strategies regulate stomatal conductance to maintain stationary leaf water potential, while trees with anisohydric strategies allow leaf …


Do Advisors Perceive Climate Change As An Agricultural Risk? An In-Depth Examination Of Midwestern U.S. Ag Advisors’ Views On Drought, Climate Change, And Risk Management, Sarah P. Church, Michael Dunn, Nicholas Babin, Amber Saylor Mase, Tonya Haigh, Linda Stalker Prokopy Oct 2017

Do Advisors Perceive Climate Change As An Agricultural Risk? An In-Depth Examination Of Midwestern U.S. Ag Advisors’ Views On Drought, Climate Change, And Risk Management, Sarah P. Church, Michael Dunn, Nicholas Babin, Amber Saylor Mase, Tonya Haigh, Linda Stalker Prokopy

Drought Mitigation Center: Faculty Publications

Through the lens of the Health Belief Model and Protection Motivation Theory, we analyzed interviews of 36 agricultural advisors in Indiana and Nebraska to understand their appraisals of climate change risk, related decision making processes and subsequent risk management advice to producers. Most advisors interviewed accept that weather events are a risk for US Midwestern agriculture; however, they are more concerned about tangible threats such as crop prices. There is not much concern about climate change among agricultural advisors. Management practices that could help producers adapt to climate change were more likely to be recommended by conservation and Extension advisors, …


Genomic And Physiological Approaches To Improve Drought Tolerance In Soybean, Avjinder Kaler Aug 2017

Genomic And Physiological Approaches To Improve Drought Tolerance In Soybean, Avjinder Kaler

Graduate Theses and Dissertations

Drought stress is a major global constraint for crop production, and improving crop tolerance to drought is of critical importance. Direct selection of drought tolerance among genotypes for yield is limited because of low heritability, polygenic control, epistasis effects, and genotype by environment interactions. Crop physiology can play a major role for improving drought tolerance through the identification of traits associated with drought tolerance that can be used as indirect selection criteria in a breeding program. Carbon isotope ratio (δ13C, associated with water use efficiency), oxygen isotope ratio (δ18O, associated with transpiration), canopy temperature (CT), canopy wilting, and canopy coverage …


Influence Of Stream Permanence, Predation, And Invasive Species On Crayfish In The Ozark Highlands With An Emphasis On Species Of Greatest Conservation Need (Orconectes Marchandi, Orconectes Eupunctus And Cambarus Hubbsi), Allyson Noelle Yarra May 2017

Influence Of Stream Permanence, Predation, And Invasive Species On Crayfish In The Ozark Highlands With An Emphasis On Species Of Greatest Conservation Need (Orconectes Marchandi, Orconectes Eupunctus And Cambarus Hubbsi), Allyson Noelle Yarra

Graduate Theses and Dissertations

Due to the ecological importance of crayfish and the increasing vulnerability of freshwater systems due to habitat loss, invasive species, and hydrologic alteration, understanding crayfish-environment relationships is crucial in the context of aquatic species conservation. I sought to examine the influence of hydrologic variation among intermittent and permanent streams on crayfish occupancy, abundance, predation risk, and potential vulnerability to invasive species effects. I conducted crayfish and environmental data sampling during two consecutive summers across 20 Ozark streams of differing permanence levels (10 intermittent, 10 permanent). In these same streams, I conducted fish and scat surveys over the course of four …


Ecological Importance Of Invader Source Population And Disturbance In Aquatic Invasions, Nicole Elizabeth Graham May 2017

Ecological Importance Of Invader Source Population And Disturbance In Aquatic Invasions, Nicole Elizabeth Graham

Graduate Theses and Dissertations

Invasive species are a global problem and their effects on recipient ecosystems may be mediated by disturbance and intraspecific variation. Crayfish can substantially influence stream structure and function, and invasive crayfish often have differential impacts than native crayfish in aquatic ecosystems. Since species traits often vary across a distribution, it is possible that invasive crayfish from different source populations may have distinct impacts on recipient ecosystem structure and function. In the Ozark Highlands of Arkansas and Missouri, USA, invasive O. neglectus (the Ringed Crayfish) may be leading to the displacement of native O. eupunctus (the Coldwater Crayfish). The objective of …


A Realistic Meteorological Assessment Of Perennial Biofuel Crop Deployment: A Southern Great Plains Perspective, Melissa Wagner, Meng Wang, Gonzalo Miguez-Macho, Jesse Miller, Andy Vanloocke, Justin E. Bagley, Carl J. Bernacchi, Matei Georgescu Jan 2017

A Realistic Meteorological Assessment Of Perennial Biofuel Crop Deployment: A Southern Great Plains Perspective, Melissa Wagner, Meng Wang, Gonzalo Miguez-Macho, Jesse Miller, Andy Vanloocke, Justin E. Bagley, Carl J. Bernacchi, Matei Georgescu

Andy VanLoocke

Utility of perennial bioenergy crops (e.g., switchgrass and miscanthus) offers unique opportunities to transition toward a more sustainable energy pathway due to their reduced carbon footprint, averted competition with food crops, and ability to grow on abandoned and degraded farmlands. Studies that have examined biogeophysical impacts of these crops noted a positive feedback between near-surface cooling and enhanced evapotranspiration (ET), but also potential unintended consequences of soil moisture and groundwater depletion. To better understand hydrometeorological effects of perennial bioenergy crop expansion, this study conducted high-resolution (2-km grid spacing) simulations with a state-of-the-art atmospheric model (Weather Research and Forecasting system) dynamically …


Severe Drought Impacts Female Pheasant Physiology In Southwest Nebraska, Jessica A. Laskowski, Gwendolyn C. Bachman, Joseph J. Fontaine Jan 2017

Severe Drought Impacts Female Pheasant Physiology In Southwest Nebraska, Jessica A. Laskowski, Gwendolyn C. Bachman, Joseph J. Fontaine

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

In 2012, Nebraska experienced one of the worst droughts since the 1930s, accompanied by abnormally high temperatures. We studied the impacts of the 2012 summer drought on female ring-necked pheasant (Phasianus colchicus) body condition and baseline and stress-induced corticosterone concentrations (CORT). We hypothesized that drought conditions would reduce pheasant body condition, increase chronic stress resulting in elevated baseline CORT levels, and down-regulate pheasant stress response to acute stressors, resulting in reduced stress-induced CORT concentrations. In southwestern Nebraska, we captured female pheasants in 2012 (pre-drought) and 2013 (post-drought). Pheasants had poorer body condition after the drought. Although female CORT …