Life Sciences Commons^™

Do Heat Waves Drive Natural Selection In Damselflies?, Adam Baranyk

Biological Sciences Undergraduate Honors Theses

Climate change has led to changes in both mean temperatures and temperature extremes over the recent years. These changes have had differential effects on animals throughout the world. Ectotherms depend on their external environment for thermal regulation, making them especially susceptible to temperature extremes. It is not yet clear whether there is a relationship between physical traits in ectotherms, and survivorship throughout a heat wave. That is, whether or not temperature extremes driven survival selection. In this study, a heat wave was simulated artificially using thermally regulated mesocosms at different temperatures (18°C, 22° C, 26° C, 30° C) with a …

Environmental And Agronomic Evaluation Of Struvite In Rice Production Systems, Diego Della Lunga

Graduate Theses and Dissertations

Furrow-irrigation constitutes an alternative water regime that has been increasingly adopted in Arkansas. Among the management of nutrients in furrow-irrigated systems, phosphorus (P) represents a substantial challenge. The environmental sustainability of rice (Oryza sativa) production systems needs to be evaluated across different water regimes and fertilizer-P sources. Therefore, the objectives of the following studies were to: i) evaluate season-long carbon dioxide (CO2) and methane (CH4) emissions and global warming potential (GWP) under different tillage treatments [i.e., conventional tillage (CT) and no-tillage (NT)] and at different site positions (i.e., up-, mid-, down-slope) along the predominant slope of a production-scale, furrow-irrigated rice …

Patterns In Winter Stonefly Distribution Along A River Continuum And Land-Use Gradient In Northwest Arkansas Streams, Zachary Tipton

Graduate Theses and Dissertations

Freshwater ecosystems are facing a crisis with extinction rates of aquatic species exceeding those of their terrestrial counterparts by up to fivefold. This decline is predominantly attributed to evolving land use patterns within watersheds, leading to chemical and physical transformations in freshwater habitats. Northwest Arkansas (NWA) represents one of the fastest-growing regions in the United States, undergoing substantial shifts in land use. Consequently, the status of aquatic life in this region remains uncertain. Addressing this concern, the latest Arkansas Wildlife Action Plan emphasizes the necessity of distribution and population data to guide conservation efforts for Species of Greatest Conservation Need …

Assessing The Evaporation Method For Soil-Water Retention Curve Development And Comparison Of Soil-Water Characteristics Across Different Tillage Practices In A Furrow-Irrigated Corn (Zea Mays L.) System, Jeferson Prass Pimentel

Graduate Theses and Dissertations

The thesis comprises three studies. The first study in this thesis (Chapter I) focused on a six-year corn field experiment to assess the influence of conservation agricultural practices on soil properties and their long-term effects on water-use efficiency and yield. Non-tillage management did not significantly reduce soil bulk density compared to conventional tillage, as no differences were observed between non-tillage and tillage systems throughout the 6-year experiment. There was no difference in total water-use efficiency among soil management practices in 2018, 2019, 2020, and 2021. Even though in one year of the study, a significant 24 kg ha-1 mm-1 improvement …

Analyzing The Adoption, Cropping Rotation, And Impact Of Winter Cover Crops In The Mississippi Alluvial Plain (Map) Region Through Remote Sensing Technologies, Zobaer Ahmed

Graduate Theses and Dissertations

This dissertation explores the application of remote sensing technologies in conservation agriculture, specifically focusing on identifying and mapping winter cover crops and assessing voluntary cover crop adoption and cropping patterns in the Arkansas portion of the Mississippi Alluvial Plain (MAP). In the first chapter, a systematic review using the PRISMA methodology examines the last 30 years of thematic research, development, and trends in remote sensing applied to conservation agriculture from a global perspective. The review uncovers a growing interest in remote sensing-based research in conservation agriculture and emphasizes the necessity for further studies dedicated to conservation practices. Among the 68 …

Evaluation Of Biochar Rate And Hemp Cultivar For The Phytoremediation Of Heavy-Metal-Contaminated Soil From The Tar Creek Superfund Site, Dietrich Thurston

Graduate Theses and Dissertations

Soil contamination by cadmium (Cd), lead (Pb), and zinc (Zn) at the Tar Creek Superfund site in Northeast Oklahoma remains a threat to the environment and local ecosystem. Phytoremediation by industrial hemp (Cannabis sativa L.) and the use of biochar (BC) have been independently shown to be effective methods to remediate heavy-metal-contaminated soils. The objective of this greenhouse study was to evaluate the effects of industrial hemp cultivar (‘Carmagnola’ and ‘Jinma’), BC rate (0, 2, 5, and 10% by volume), soil contamination level (low, medium, and high), and their interactions on above- and belowground (AG and BG, respectively) plant dry …

Understanding The Operations And Decision-Making Of Cow-Calf Farmers In Northwest Arkansas, Clayton Weyl

Agricultural Economics and Agribusiness Undergraduate Honors Theses

Societal pressure on farmers has become a more central part of the rhetoric surrounding livestock production. This study includes farmers in the discourse on the rhetoric surrounding climate change via interviews and simulations tailored to their operation. Previous research has addressed regenerative agricultural practices and conditions that influence farmer decision-making, but little research has analyzed decision-making in tandem with environmental practices. The literature reveals that cow-calf producer decision-making is influenced by their reliance on cattle as an income source, and farmers overall choose climate-friendly practices based on their perceptions about climate change. The goal of this research was to gather …

Effects Of Landscape And Yard Features On Mammals In Residential Yards In Northwest Arkansas, Emily Johansson

Graduate Theses and Dissertations

The human footprint is rapidly expanding, and wildlife habitat is continuously being converted to human residential properties. Most wildlife residing in developing areas are displaced to nearby undeveloped areas. However, some animals can coexist with humans and acquire the necessary resources (food, water, shelter) within the human environment. This may be particularly true when development is low intensity, as in suburban yards. Due to the wide variety in how homeowners utilize their yards, they can be considered individually managed “greenspaces.” These yards can provide a range of food (e.g., bird feeders, compost, gardens), water (bird baths and garden ponds), and …

An Overview Of Serial Depletions Of Global Marine Fisheries 1950 To 2019, Alison Follmer

Biological Sciences Undergraduate Honors Theses

Overfishing is a global issue that poses a significant risk to the entire ocean ecosystem in diminishing biodiversity and ecosystem function. This thesis examined the pattern and pace of fisheries depletions due to commercial fishing during the past 70 years. The Food and Agriculture Organization of the United Nations (FAO) Division of Fisheries and Aquaculture maintains a database of global hauls of marine taxa (reported in metric tonnes) from 1950 – 2019. These data were queried to determine the total number and sequence of fisheries depletions documented by the historic record. Analysis of this database showed progressive, linearly-increasing exploitation of …

Potential Control Of Invasive Mesquite Through Improving The Consumer’S Understanding Of Liquid Smoke Applications., Seth W. Ellsworth

Graduate Theses and Dissertations

Mesquite trees continue to invade forests and range lands in many countries across the world. The cost to remove these trees is staggering. In Texas, landowners spent $25 million over a 10- year period to clear 300,000 ha of mesquite trees, a fraction of the 22 million ha of Texas land affected by this invasion. Estimates are that the mesquite continues to negatively impact one to two percent of additional land in selected counties each year in Texas. However, the problem is not unique to Texas, but rather to the 44 species of mesquite trees, belonging to the genus Prosopis …

Sustainability And Health Impacts Of Pulse Crops In The United States Using Life Cycle Assessment, Prathamesh A. Bandekar

Graduate Theses and Dissertations

Environmental sustainability and human health impact of pulses produced and consumed in the United States was assessed using life cycle assessment (LCA). The study included three objectives 1) to estimate environmental impact of current production and consumption practices in the United States using attributional LCA; 2) to estimate environmental and human health impact of iso-caloric diets containing varying amounts of pulses using Hybrid-LCA and Combined Nutritional and Environmental-LCA (CONE-LCA); and 3) to estimate environmental impact of increased demand for pulses using consequential LCA. Scope of the study varied for each objective with system boundary encompassing cradle-to-grave activities for objective 1 …

Assessment Of Novel Protein Ingredient Arthrospira Platensis (Microalgae) And Soybean Genotype Amino Acid And Oil Selection Improvements On Broiler Performance, Savannah Wells Crafton

Graduate Theses and Dissertations

Two experiments were conducted to assess the efficiency of including novel protein ingredient Arthrospira platensis or improved soybean meal in a broiler diet. The first experiment aimed to determine the feeding value of soybean meal produced from varieties of soybeans bred for increased amino acid content (SBAA) improved oil content (SBO) compared to a conventional soybean variety in an ANOVA design fed to Cobb 500 female broilers for 28-42d of age. The SBAA and SBO soybeans contained overall higher amino acid content and lower oligosaccharide content compared to the conventional soybean variety in addition to improved oil quality. The second …

Seasonal Patterns In Activity And Occupancy Dynamics Of The Imperiled Spotted Turtle (Clemmys Guttata), Ellery Vaughn Lassiter

Graduate Theses and Dissertations

Wetland ecosystems are often spatially patchy across a landscape and exhibit seasonal patterns in water levels, resulting in the need for aquatic wildlife to use several different wetland patches across a season. The ecology of semi-aquatic freshwater turtles is especially complex because individuals often move among a variety of habitats to meet life history needs and these habitat requirements often differ across a season. Understanding the temporal and spatial scale in which turtles move and distribute across the landscape is vital for effective management, especially in the face of continued habitat fragmentation and climate change. Thus, we sought to understand …

Societal Sustainability: Projects To Address The Three Dimensions Of A Sustainable Future, Braden K. Bateman

Graduate Theses and Dissertations

Sustainability is an important, commonly discussed societal goal regarding assurance of resources for the world to be able to enjoy a prosperous future. Three primary dimensions of sustainability include environmental, economic, and social sustainability, and objectives for various projects can be aimed at any of the three dimensions to pursue societal sustainability. Solar installations, which can be used to pursue environmental and economic sustainability, convert abundant sunlight to electricity, displacing fossil fuel use that contributes harmful greenhouse gases to the atmosphere. The regulatory environment at the state level has a significant impact on the feasibility of solar projects. At present, …

Competing Behaviors Of Thermoregulation And Ambush Foraging In The Timber Rattlesnake (Crotalus Horridus Horridus): A Mechanistic Assessment Of Thermal Conduction, Larry K. Kamees

Graduate Theses and Dissertations

The interaction between the biophysical environment and ectotherm morphology elicits behaviors designed to maintain internal body temperature (Tb) within a range that promotes physiological functions. The short-term requirements of mass (energy requirements) and heat balance are subject to tradeoffs imposed by the organisms current physiological (heat and mass budgets) and environmental (biophysical, demographic, social, and predation) constraints and available resources. In temperate forests, extreme temperatures are common in summer even with intermittent sun exposure due to dense canopy cover. In Spring and Fall, temperatures can range from below freezing to 35 ℃ in 24 hrs. An ambush predator like the …

Assessing Consumer Demand, Producer Profitability, And The Environmental Impacts Of Conservation Agriculture Adoption In Sub-Saharan Africa, Willy Byamungu Mulimbi

Graduate Theses and Dissertations

This dissertation explores three aspects of conservation agriculture (CA) in the Sub-Saharan African region (SSA). The first article examines the demand side of CA and explores whether urban maize (Zea mays L.) consumers in the Democratic Republic of the Congo (DRC) would be willing to pay a premium for CA-produced maize flour. The second article estimates the effects CA provides to adopters and their farms in smallholder farming systems in the DRC, focusing on changes in soil properties and cowpea (Vigna unguiculata) yields. The final article uses a Life Cycle Assessment (LCA) approach to monetize the environmental impacts of adopting …

The Effect Of Water Management And Ratoon Rice Cropping On Methane Emissions And Harvest Yield In Arkansas, Marguerita Leavitt

Graduate Theses and Dissertations

Sustainable intensification of rice farming is crucial to meeting human food needs while reducing environmental impacts. Rice produces 8% of all anthropogenic CH4, which is a potent greenhouse gas. CH4 emissions can potentially be reduced by cultivation practices that minimize the number of days the fields are saturated, such as dry-seeding instead of water-seeding and irrigation using the alternate wetting and drying (AWD) technique instead of delayed, continuous flooding (DF). Ratoon cropping, wherein a second crop of rice is grown from the harvested stubble of the first crop, can be used to produce additional yield with minimal labor, but may …

Conservation Of Open-Canopy-Associated Wildlife: Multi-Scale Management Impacts On Imperiled Herpetofauna, Ethan Joseph Royal

Graduate Theses and Dissertations

The loss of open-canopy ecosystems throughout North America has precipitated declines in reptile and amphibian species associated with these habitat types. Current efforts to restore open-canopy ecosystems are underway in many areas, but the local distributions of, habitat characteristics required by and the effects of management actions on many herpetofauna species are poorly understood or entirely unknown. Research examining relationships among herpetofauna and their environments is often complicated by the extremely low detectability seen in many studies. We used landscape-scale, assemblage-level surveys to investigate the occupancy patterns and habitat associations of open-canopy-associated herpetofauna in two regions, as well as gain …

Reconstructing Bison And Mammoth Migration During The Late Pleistocene And Early Holocene Of Central Texas Using Strontium Isotopes, Joshua John Porter

Graduate Theses and Dissertations

During the Late Pleistocene (LP; past 130,000 years), over two-thirds of large mammal (>45kg) species went extinct globally. While the role of humans is hotly debated, the effect of these extinctions is growing clearer; the extinctions resulted in widespread and lasting faunal community reorganization. However, the impact of these extinctions on dietary and migratory behavior within faunal communities is unknown. Our study examines the impact of the megafaunal extinctions on the dietary and migratory behavior of surviving Bison individuals in Texas using carbon, oxygen, and strontium isotopes. Strontium isotopes are incorporated into mammalian enamel during their tooth development and …

Root Phenotyping Of Peptide-Treated Glycine Max, Salem Jackson

Biological Sciences Undergraduate Honors Theses

Plant elicitor peptides (Peps) – endogenous chains of amino acids involved in natural plant defense – have been shown to decrease damage from herbivores and pathogens by inducing an immune response, increasing the emission of volatile organic compounds (VOCS), transcripts, and metabolites. Exogenous treatment of soybean seeds with plant elicitor peptide GmPep3 has been shown to induce these broad-spectrum defenses and offers a new method for increasing crop yield. However, the effects of GmPep3 on indicators of soybean health – root characteristics, growth stages, etc. – have not been fully realized.

Using the root-phenotyping platform RhizoVision Explorer, several root traits …

Rodent Dental Microwear Texture Analysis As A Proxy For Fine-Scale Paleoenvironment Reconstruction, Jenny H. E. Burgman

Graduate Theses and Dissertations

Dental microwear texture analysis (DMTA) of fossil fauna has become a valuable tool for dietary inference and paleoenvironment reconstruction. Most of this work has utilized larger taxa with larger home ranges. These studies may result in broader-scale habitat inferences that could mask the details of complex mosaic habitats. Rodent DMTA offers an opportunity to work at finer spatial scales because most species have smaller home ranges. Rodents are also keystone species within their ecosystems, abundant, ubiquitous, and found in many fossil deposits. These attributes make them excellent proxies for environmental reconstructions. However, the application of DMTA to rodents remains relatively …

Comparison Of Carbon Footprints Of School Lunches In Dangriga, Belize, And Northwest Arkansas, Lauren Greenwood

Crop, Soil and Environmental Sciences Undergraduate Honors Theses

The original purpose of this study was to investigate differences in carbon footprints of school lunches by comparing a school in Arkansas, USA, and a school in Belize. Due to complications imposed by the COVID-19 pandemic, the purpose was revised to gathering preliminary data about the school lunch program at a school in Northwest Arkansas; data were to be used to estimate CO2-equivalent emissions for cafeteria energy use, meal ingredients from the two most popular meals served, and food transportation at the last point in the supply chain (food service delivery to school). This study highlights the intersection of food …

Potato Processing In The Home: Sustainability And Nutritional Impacts, Aubin Payne

Biological and Agricultural Engineering Undergraduate Honors Theses

Potatoes are the world's fourth most consumed crop. Their versatility and long shelf-life make them a staple food for millions of people worldwide. Still, the increasing consumption of highly processed potato products in developed countries has damaged the public's appreciation of potatoes as a valuable source of essential nutrients. Additionally, as public awareness of environmental sustainability increases, the average consumer is more likely to value processing methods that mitigate environmental damage.

Researchers simulated several home storage and processing conditions to find out how nutrition and environmental impact are affected by the home processing timeline. Then, a nutrient analysis, life cycle …

Impact Of A Cattle Crossing On Water Quality Along A Tributary Of The Muddy Fork Of The Illinois River, Northwest Arkansas, Nicholas Valentini

Animal Science Undergraduate Honors Theses

Cattle are known to have an effect on water quality in various bodies of water. Studying how cattle impact water quality along various streams and tributaries is important to understanding how certain water parameters may be affected at the individual farm level. It is known that unrestricted access to a cattle crossing has been shown to increase the occurrence of downstream pollutants such as E. coli, ammonium, total kjeldahl nitrogen, total suspended solids, total phosphorus, and turbidity. However, many studies focus on large-scale operations and neglect the individual farm level. In this study, samples were collected twice for each …

Exploring The Effects Of Varied Land Use On Elemental Concentrations Within Streams, Logan Jennings

Biological and Agricultural Engineering Undergraduate Honors Theses

It is well documented that human activity influences the chemistry of surrounding waters. As such, it is possible that there is a link between land use within a watershed and the chemical composition of the stream. The objectives of this study are to determine if varied land use does affect the concentrations of macronutrients and trace elements present in the streams of Northwest Arkansas, and if so, to determine what extent urban and agricultural development are responsible for these changes. Water samples were collected across 19 streams in the Northwest Arkansas region between January and March of 2022. Water samples …

Using Ai To Examine Nocturnal Moth Pollination, Conor Moriarty

Biological Sciences Undergraduate Honors Theses

The importance of insect-mediated agriculture cannot be understated especially in the wake of pollinator population declines. Most research of insect-mediated pollination is focused on diurnal pollinators like the honeybee (Apis mellifera). Deepening our understanding of how other pollinators, such as nocturnal pollinators, can benefit agriculture and ecosystems will be very important as honeybee populations decline. I explored nocturnal moth interactions with flowering apple flowers during their pollination season to better understand how these nocturnal pollinators interact with the plants. To accomplish this, I used a University of Arkansas farm area with a dedicated apple orchard. I gathered my raw data …

Root Phenotyping Of Peptide-Treated Glycine Max, Salem Jackson, Fiona Goggin

Inquiry: The University of Arkansas Undergraduate Research Journal

Plant elicitor peptides (Peps) – endogenous chains of amino acids involved in natural plant defense – have been shown to decrease damage from herbivores and pathogens by inducing an immune response, increasing the emission of volatile organic compounds (VOCS), transcripts, and metabolites. Exogenous treatment of soybean seeds with plant elicitor peptide GmPep3 has been shown to induce these broad-spectrum defenses and offers a new method for increasing crop yield. However, the effects of GmPep3 on indicators of soybean health – root characteristics, growth stages, etc. – have not been fully realized. Using the root-phenotyping platform RhizoVision Explorer, several root traits …

Arkansas Bulletin Of Water Research - Issue 2021-2022, Erin Grantz, Lillie Haddock, Brian E. Haggard

Arkansas Bulletin of Water Research

The Arkansas Bulletin of Water Research (Bulletin) is a publication of the Arkansas Water Resources Center (AWRC). We publish the Bulletin to communicate the major findings of research funded by the Water Resources Research Act Section 104(b) in Arkansas. This research is relevant to Arkansas water stakeholders, and the Bulletin provides an easily searchable and aesthetically engaging access option.

This is the fourth publication of the Bulletin. This issue contains final reports from research projects that were funded by the 104(b) program in fiscal years 2019 and 2020. The articles in this issue can be cited as an AWRC publication. …

How Are Agricultural Research Projects Conceiving Innovation? An Assessment Of The European Union Multi-Actor Projects, Samuel Brea Martinez-Collado

Graduate Theses and Dissertations

Horizon research programs are the European Union’s lighthouse for innovation and research concerning the agri-food chain, the management of natural resources, and the bioeconomy. Their innovation strategy approach is one that pursues the practical application of the research via the collaboration of all actors involved. Such strategy is the reflection of a Multi-Actor Approach as their procedure to enhance innovation. This paper presents the main trends and directions 101 Multi-Actor Projects (MAPs) are following on said approach towards innovation. The analysis is based on the use of well-defined “pathways” and “measures” proposed in the Guidelines for Evaluation of Innovation in …

The Effects Of Commercial Harvest On The Density And Demography Of Aquatic Turtles In Arkansas, Andrhea Darleen Massey

Graduate Theses and Dissertations

The United States is home to the second highest concentration of turtle species in the world, after Asia. As of 2018, there are 57 turtle species recognized within the US, 40% of which are listed as threatened or endangered, with the primary threats to population persistence identified as over-consumption and/or habitat loss. Within the US, the Mississippi Alluvial Valley (MAV) region represents the second highest turtle species richness, after the Mobile River Basin. The MAV region of Arkansas is one of the least regulated in terms of commercial aquatic turtle harvest and has undergone large-scale habitat conversion from bottomland hardwood …