Natural Resources and Conservation Commons^™

Sustainable Irrigation Based On Co-Regulation Of Soil Water Supply And Atmospheric Evaporative Demand, Jingwen Zhang, Kaiyu Guan, Bin Peng, Ming Pan, Wang Zhou, Chongya Jiang, Hyungsuk Kimm, Trenton E. Franz, Robert F. Grant, Yi Yang, Daran R. Rudnick, Derek M. Heeren, Andrew E. Suyker, William L. Bauerle, Grace L. Miner

School of Natural Resources: Faculty Publications

Irrigation is an important adaptation to reduce crop yield loss due to water stress from both soil water deficit (low soil moisture) and atmospheric aridity (high vapor pressure deficit, VPD). Traditionally, irrigation has primarily focused on soil water deficit. Observational evidence demonstrates that stomatal conductance is co-regulated by soil moisture and VPD from water supply and demand aspects. Here we use a validated hydraulically-driven ecosystem model to reproduce the co-regulation pattern. Specifically, we propose a plant-centric irrigation scheme considering water supply-demand dynamics (SDD), and compare it with soil-moisture-based irrigation scheme (management allowable depletion, MAD) for continuous maize cropping systems in …

Magnitude And Uncertainty Of Nitrous Oxide Emissions From North America Based On Bottom-Up And Top-Down Approaches: Informing Future Research And National Inventories, R. Xu, Hanqin Tian, N. Pan, R. L. Thompson, J. G. Canadell, E. A. Davidson, C. Nevison, W. Winiwarter, H. Shi, S. Pan, J. Chang, P. Ciais, Shree Dangal, A. Ito, R. B. Jackson, F. Joos, R. Lauerwald, S. Lienert, T. Maavara, D. B. Millet, P. A. Raymond, P. Regnier, F. N. Tubiello, N. Vuichard, K. C. Wells, C. Wilson, J. Yang, Y. Yao, S. Zaehle, F. Zhou

School of Natural Resources: Faculty Publications

We synthesized N₂O emissions over North America using 17 bottom-up (BU) estimates from 1980– 2016 and five top-down (TD) estimates from 1998 to 2016. The BU-based total emission shows a slight increase owing to U.S. agriculture, while no consistent trend is shown in TD estimates. During 2007–2016, North American N₂O emissions are estimated at 1.7 (1.0–3.0) Tg N yr⁻¹ (BU) and 1.3 (0.9–1.5) Tg N yr⁻¹ (TD). Anthropogenic emissions were twice as large as natural fluxes from soil and water. Direct agricultural and industrial activities accounted for 68% of total anthropogenic emissions, 71% of …

Plastic Recycling Is Inefficient And Expensive, Clark S. Adomaitis

Capstones

Plastics production and incineration contributes more than 850 million metric tons to the emissions that are causing climate change. Emissions are growing at a moment when scientists and world leaders are in agreement that they need to dramatically decrease. Environmentalists say that plastic production makes up 4.5% of global greenhouse gas emissions. New plastic plants opening in the U.S. do not line up with emission reduction goals.

At the end of plastics’ lives, a lot of what we’re putting into our recycling bins isn’t getting recycled. In fact, only 18% of trash from New York City homes is actually recycled. …

Identification And Characterization Of Forest Fire Risk Zones Leveraging Machine Learning Methods, Joshua Balson, Matt Chinchilla, Cam Lu, Jeff Washburn, Nibhrat Lohia

SMU Data Science Review

Across the United States, record numbers of wildfires are observed costing billions of dollars in property damage, polluting the environment, and putting lives at risk. The ability of emergency management professionals, city planners, and private entities such as insurance companies to determine if an area is at higher risk of a fire breaking out has never been greater. This paper proposes a novel methodology for identifying and characterizing zones with increased risks of forest fires. Methods involving machine learning techniques use the widely available and recorded data, thus making it possible to implement the tool quickly.

The Effects Of Hydrologic Heterogeneity On Harmful Algal Blooms In Freshwater Reservoir, Lake Sinclair, Georgia, Margaret Blackledge

Biology Theses

Aquatic habitats are frequently studied after a major water quality problem like the occurrence of an algal bloom. In this study, A proactive rather than a reactive response was considered, where the complexity of conditions conducive to uncontrolled cell growth were studied before a bloom took place by sampling regularly. This study aimed to monitor water quality by monthly sampling of algal communities for approximately one year. As the base of the aquatic food web, algae are a highly diverse group of organisms with varying sensitivity to physical and chemical changes in the environment. Four shallow sites were monitored at …

Ten Simple Rules For Creating A Scientific Web Application, Jessica L. Burnett, Renee Dale, Chung-Yi Hou, Gabriela Palomo-Muoz, Kaitlin Stack Whitney, Steve Aulenbach, Robert Sky Bristol, Denis Valle, Tristan P. Wellman

School of Natural Resources: Faculty Publications

The use of scientific web applications (SWApps) across biological and environmental sciences has grown exponentially over the past decades or so. Although quantitative evidence for such increased use in practice is scant, collectively, we have observed that these tools become more commonplace in teaching, outreach, and in science coproduction (e.g., as decision support tools). Despite the increased popularity of SWApps, researchers often receive little or no training in creating such tools. Although rolling out SWApps can be a relatively simple and quick process using modern, popular platforms like R shiny apps or Tableau dashboards, making them useful, usable, and sustainable …

Soil Microbial Community Dynamics In Response To Prescribed Extreme Fires Following Juniperus Virginiana Invasion In The Loess Canyons Of Nebraska, Julie A. Fowler

School of Natural Resources: Dissertations, Theses, and Student Research

In Nebraska and other regions of the Great Plains, the conifer Juniperus virginiana (eastern redcedar) is converting grasslands to dense woodlands. This is driven by the interacting drivers of fire suppression, altered grazing regimes, climate change and other anthropogenic factors, impacting the provisioning of ecosystem services. This vegetation state transition modifies water resource regulation and biogeochemical cycles leading to altered edaphic properties including soil microbial community composition. To restore these grasslands and control J. virginiana spread, prescribed extreme burns are implemented as a management tool through local prescribed burn associations. We hypothesized that the alternative state transition to dense J. …

Constraints To Waterfowl Hunting By Hunters And Anglers In The Central United States, Matthew P. Hinrichs, Matthew P. Gruntorad, Julia A. Nawrocki, Mark P. Vrtiska, Mark A. Pegg, Christopher J. Chizinski

School of Natural Resources: Faculty Publications

Waterfowl hunting participation has been on the decline since the mid‐1980s. We used a web‐based survey to better understand waterfowl hunting constraints (i.e., factors that limit or prohibit participation and enjoyment in leisure activities) among hunters and anglers that hunted or did not hunt waterfowl in the central United States. Forty‐eight constraint items were condensed into 10 constraint factors: Rules and Regulations, Waterfowl Identification, Cost, Waterfowl Hunting Skills, Land Access and Permissions, Interference by Other Hunters, Travel, Social, Waterfowl Populations, and Views of Others. We observed significant effects of both state of residence and activity type (i.e., frequent waterfowl hunters, …

A Physiological Signal Derived From Sun-Induced Chlorophyll Fluorescence Quantifies Crop Physiological Response To Environmental Stresses In The U.S. Corn Belt, Hyungsuk Kimm, Kaiyu Guan, Chongya Jiang, Guofang Miao, Genghong Wu, Andrew Suyker, Elizabeth A. Ainsworth, Carl J. Bernacchi, Christopher M. Montes, Joseph A. Berry, Xi Yang, Christian Frankenberg, Min Chen, Philipp Köhler

School of Natural Resources: Faculty Publications

Sun-induced chlorophyll fluorescence (SIF) measurements have shown unique potential for quantifying plant physiological stress. However, recent investigations found canopy structure and radiation largely control SIF, and physiological relevance of SIF remains yet to be fully understood. This study aims to evaluate whether the SIF-derived physiological signal improves quantification of crop responses to environmental stresses, by analyzing data at three different spatial scales within the U.S. Corn Belt, i.e. experiment plot, field, and regional scales, where ground-based portable, stationary and space-borne hyperspectral sensing systems are used, respectively. We found that, when controlling for variations in incoming radiation and canopy structure, crop …

Towards A More Comprehensive Understanding Of Wild Pig (Sus Scrofa) Impacts On Agricultural Producers: Insights From A Texas Case Study, Keith M. Carlisle, Nicole Didero, Sophie Mckee, Julie Elser, Stephanie A. Shwiff

United States Department of Agriculture Wildlife Services: Staff Publications

This research investigates the impacts of invasive wild pigs (Sus scrofa Linneaus) on agricultural producers in Texas, with the aim of identifying and describing all categories of wild pig impacts and quantifying the extent of producers’ over- or underestimation of their total wild pig-related costs in 2018, as compared to calculations based upon data subsequently provided by the producers about individual wild pig-related costs and losses. Based on interviews with 23 producers in 16 Texas counties, we identified more than 20 discrete categories of negative impacts and negligible positive impacts associated with wild pigs. Among them were categories that have …

Implications Of Condition Shifts On Shallow Lakes, Alicia Skolte

Biology Graduate Theses

Shallow lakes have undergone condition shifts throughout time by natural causes, management actions, or a combination of the two. Because shallow lakes are especially vulnerable to shifts towards turbid conditions, management actions on shallow lakes have focused on water level/retainment, biomanipulations, the management/removal of non-native species, and land-use changes. This review compiles a summary on ecosystem shifts including a discussion on the frequency of shifts historically and the importance and causes of those shifts, trophic cascades, and the influence of introduced species in shallow lakes. This review will then examine case-studies of management-linked shifts and explain current shift theory. Next, …

Feeding Patterns And Diet Overlap Of Muskellunge And Co-Occurring Piscivores In Minnesota Lakes, Kamden Glade

Biology Graduate Theses

Muskellunge Esox masquinongy are the largest member of the family Esocidae found in Minnesota and are managed for trophy angling opportunities with large minimum size requirements, limited harvest, and stocking to support existing populations or expand angling opportunities. While Muskellunge impacts at the community level appear minimal based on available literature, relatively little is known about Muskellunge diets, eat the le particularly in Minnesota. In this study, we used gastric lavage to examine gut contents of Muskellunge, Northern Pike Esox lucius, Walleye Sander vitreus, and Largemouth Bass Micropterus salmoides. Diets were quantified using an index of relative importance (IRI) and …

Reproductive Success Of Captive-Reared Allegheny Woodrats (Neotoma Magister) Released Into Genetically Depauperate Populations, Miracle M. Davis, Timothy J. Smyser, Scott A. Johnson, Joseph Duchamp, Jeffery L. Larkin, Robert K. Swihart, Jacqueline M. Doyle

United States Department of Agriculture Wildlife Services: Staff Publications

Habitat fragmentation and degradation have led to a proliferation of small and isolated populations that are vulnerable to genetic erosion. Reduction in habitat and concomitant declines in population connectivity can expediate the collapse of species that exist as natural metapopulations. In recent years, Allegheny woodrats (Neotoma magister) have experienced local extirpations and declines in genetic diversity across their range due to disease-related mortality, reduced food availability, and disruption of connectivity among subpopulations. In response, we developed a captive-breeding program to facilitate genetic management of isolated woodrat populations in Indiana. Between 2010 and 2012, 27 captive-reared individuals were released to four …

Cover Crop Effects On Near-Surface Soil Aggregate Stability In The Southern Mississippi Valley Loess (Mlra 134), Chandler M. Arel

Crop, Soil and Environmental Sciences Undergraduate Honors Theses

Intensive agricultural cultivation within major land resource area (MLRA) 134, the Southern Mississippi Valley Loess, has led to soil erosion, soil compaction, and the overall destabilization of near-surface soil aggregates. The use of cover crops during the agricultural offseason has been shown to help alleviate soil compaction and provide stabilizing effects against soil erosion, which are particularly important as the silty soils of MLRA 134 have a large erosion potential. This study evaluated the effects of cover crop and no-cover crop treatment on silt-loam soils within MLRA 134. Treatments were implemented during Fall 2018 and Fall 2019 and consisted of …

Biodiversity Scale-Dependence And Opposing Multi-Level Correlations Underlie Differences Among Taxonomic, Phylogenetic And Functional Diversity, Nadejda A. Mirochnitchenko, Erica F. Stuber, Joseph J. Fontaine

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

Aim: Biodiversity is a multidimensional property of biological communities that represents different information depending on how it is measured, but how dimensions relate to one another and under what conditions is not well understood. We explore how taxonomic, phylogenetic, and functional diversity can differ in scale-of-effect dependence and habitat-biodiversity relationships, and subsequently how spatial differences among biodiversity dimensions may arise. Location: Nebraska, United States. Taxon: Birds. Methods: Across 2016 and 2017, we conducted 2,641 point counts at 781 sites. We modeled the occupancy of 141 species using Bayesian Bernoulli-Bernoulli hierarchical logistic regressions. We calculated species richness (SR), phylogenetic diversity (PD), …

American Burying Beetle, Plant Richness, And Soil Property Responses To Collapse Of Juniperus Virginiana Woodlands With Fire, Alison K. Ludwig

Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research

Grasslands are declining in the Great Plains due to land use changes, woody plant encroachment, and loss of historic fire cycles. Prescribed burn associations have utilized prescribed fire to collapse invading woodlands and allow the restoration of grasslands. This fire is considered “extreme” because it is capable of changing the structure and function of an ecosystem. Our study site is the Loess Canyons Experimental Landscape, a long-term, ecoregion-scale experiment to apply prescribed fire across the region to restore grasslands. The Nebraska Natural Legacy Project established the Loess Canyons ecoregion as a Biologically-Unique Landscape in 2005 with the state’s wildlife action …

Identification Of Phosphorous Loading Point Source Facilities To 303(D) Listed Nutrient Impaired Waters Through Watershed Delineation Using Arcgis For Life Cycle Assessment Applications, John Zimmerman

Chemical Engineering Undergraduate Honors Theses

The work done for this project is part of a larger “life cycle assessment (LCA) of novel electrochemical phosphorus recovery technology at the wastewater treatment plant and U.S. watershed scales” (Morrissey 2019). The goal of that LCA is to determine “environmental impacts of implementing electrochemical struvite recovery at the wastewater treatment plant, U.S watershed, and global scales” (Morrissey 2019). This project’s goal is to identify locations deemed more sensitive to eutrophication impacts. The results will be used as part of the life cycle inventory (LCI) accounting for geographically explicit phosphorus flows. The waters identified as impaired were sourced from the …

Ecological Factors Influencing Population Dynamics Of The Mississippi Sandhill Crane, Grus Canadensis Pulla, Henry W. Woolley

LSU New Orleans Theses and Dissertations

My dissertation encompasses three studies involving ecological factors influencing the Mississippi sandhill crane (Grus canadensis pulla) population at Mississippi Sandhill National Wildlife Refuge. To examine influences on the historical population I studied trends in nesting, number of chicks fledged annually, and their environmental and biotic drivers during 1991-2018. I expected precipitation to be positively associated with population measures and drought, extreme heat, and predation to be inversely related to population measures. To examine the influence of current habitat food production on the crane population I quantified measures of production in 2018 and 2019 and their relationship to time …

Data Analytics For Sustainable Food And Agriculture Systems, Megan Lord Reavis

Graduate Theses and Dissertations

The increasing concentration of anthropogenic greenhouse gases in the atmosphere is altering the climate, posing a serious threat to global agriculture and food security. Agriculture and food production contribute a quarter of all GHG emissions produced, so there is a critical need to limit emissions in this area while increasing food production to feed the anticipated 10 billion people by 2050. To address the needs of the future, data-driven solutions are needed to guide decision-making and provide support for actionable climate mitigation and survival strategies. Research efforts must be focused on analyzing problems on multiple scales, identifying new ways to …

Economic Estimates Of Wild Hog (Sus Scrofa) Damage And Control Among Young Forest Plantations In Alabama, Micah Fern, Rebecca Barlow, Chris Slootmaker, John Kush, Stephanie Shwiff, Larry Teeter, Jim Armstrong

United States Department of Agriculture Wildlife Services: Staff Publications

Operating as ecological engineers, the increased distribution and abundance of wild hogs (Sus scrofa) has caused considerable socio-economic impacts. The international scope of economic research providing wild hog damage estimates are often confined to agricultural crops, while damage estimates among forest plantations are lacking. In Alabama, private landowners hold the majority of timberland acreage and are less equipped to absorb financial losses from wild hog damage than their industrial counterparts. A survey was conducted to estimate the economic impact of wild hogs, namely costs of damage and control, to privately owned forestlands. The survey was distributed in the …