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How Are Agricultural Research Projects Conceiving Innovation? An Assessment Of The European Union Multi-Actor Projects, Samuel Brea Martinez-Collado Dec 2021

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 Dec 2021

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 …


The Electrification Of The Kitchen: On The Energy Consumption Of Common Electric Cooking Appliances, Hozen Ricchie Rose Asok Rose Dec 2021

The Electrification Of The Kitchen: On The Energy Consumption Of Common Electric Cooking Appliances, Hozen Ricchie Rose Asok Rose

Graduate Theses and Dissertations

In developed countries, electricity has been gaining popularity as a source of energy for meal preparation. Utilizing electricity produced from renewable resources along with efficient electrical cooking appliances could result in sustainable clean cooking. The first objective of this research was to study the efficiency of common electrical cooking appliances—namely induction, resistance plate, resistance coil, infrared, and electric pot— by the water boiling test and the simmering test. The induction and electric pot were observed as the most efficient devices for the water boiling test. For simmering, which mimics many cooking processes, the electric pot and resistance coil were the …


Optimization Of Nitrogen Removal Rate In One-Stage Reactor Through Partial Nitrification Anammox Process During Direct Treatment Of Poultry Litter Wastewater, Yiting Xiao Dec 2021

Optimization Of Nitrogen Removal Rate In One-Stage Reactor Through Partial Nitrification Anammox Process During Direct Treatment Of Poultry Litter Wastewater, Yiting Xiao

Graduate Theses and Dissertations

Anammox is an increasingly common process used for the treatment of reject water and even mainstream wastewater due to its low oxygen demand. However, anammox is not commonly utilized in the direct treatment of poultry litter because of the high organic content, which would inhibit the anammox process. Thus, this project is aimed at optimizing the nitrogen removal rate through partial nitrification anammox process (PN/A) to treat synthetic poultry litter wastewater. Nitrogen removal efficiencies will therefore be improved through optimizing the combination of three operating parameters including hydraulic retention time (HRT), dissolved oxygen (DO) concentration, and carbon to nitrogen (C/N) …


A 60- Year Record Of The Demotechnic Index Of States, 1960-2019, Gavin James Kellough Dec 2021

A 60- Year Record Of The Demotechnic Index Of States, 1960-2019, Gavin James Kellough

Graduate Theses and Dissertations

A country’s dependency on energy resources can be interpreted through the calculation of energy indices. The Demotechnic Index (DI) was used to determine the trajectory of energy efficiency of each state in the United States over the period 1960-2019. The DI serves as a measure of the energy intensity of states and a proxy for energy sustainability of each state.The DI is the ratio of total energy use to total metabolic energy demand of a population. Mathematically, DI = (E_T-E_M)/E_M E_T represents the total energy used (metabolic energy + technological energy in kilojoules annually, kJ/y), while EM represents the basic …


Body Mass And Body Condition Variation Of Mallards (Anas Platyrhynchos) Within And Among Winters Within The Lower Mississippi Alluvial Valley, John Thompson Veon Dec 2021

Body Mass And Body Condition Variation Of Mallards (Anas Platyrhynchos) Within And Among Winters Within The Lower Mississippi Alluvial Valley, John Thompson Veon

Graduate Theses and Dissertations

Most North American waterfowl overwinter in southern North America before migrating back to breeding grounds in the northern US and Canada. These species face the challenge of needing to maintain or increase their body mass during an environmentally difficult winter period. Successful body mass maintenance during the winter period has major ramifications not only for their winter survival but for their fitness across the entire year. Recent research in Europe and the western United States suggests that the body mass of mallards (Anas platyrhynchos) has increased from the late 1960s to early 2000s. However, the factors responsible for increases in …


Use Patterns And Influencing Factors Of Irrigation Best Management Practices In The Lower Mississippi River Basin, Merri E. Day Dec 2021

Use Patterns And Influencing Factors Of Irrigation Best Management Practices In The Lower Mississippi River Basin, Merri E. Day

Graduate Theses and Dissertations

This study uses the 2016 Irrigation Survey from Arkansas, Louisiana, and Mississippi to document the use of irrigation best management practices (IBMPs), analyze use patterns, and use quantitative methods to determine factors that influence producers’ decisions regarding IBMPs. IBMPs included in the survey can be grouped as: field management practices (zero-grade leveling, precision-grade leveling, end blocking, warped surface, and deep tillage), water flow control practices (computerized pipe-hole selection, multiple-inlet irrigation, surge irrigation, alternate wetting and drying, cutback irrigation, flow meters, and pump timers), water recovery/storage practices (tail-water recovery system and on-farm storage reservoir), and advanced irrigation scheduling practices (soil moisture …


Data Analytics For Sustainable Food And Agriculture Systems, Megan Lord Reavis Dec 2021

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 …


Community Perceptions And Aesthetic Valuation Of Remediation Gardens, Rachel Bechtold Dec 2021

Community Perceptions And Aesthetic Valuation Of Remediation Gardens, Rachel Bechtold

Graduate Theses and Dissertations

Creating successfully remediated landscapes may rely on both natural resources and human perception in landscape design. Urban areas present a dynamic environment wherein communities and nature compete for resources and space. This dissertation study was designed to better understand aesthetic perceptions of native plants capable of land remediation in midwestern communities. Findings from this study show the importance of aesthetic perceptions of stakeholders towards rehabilitated landscapes and the importance of organizing indicators for future design decisions in an interdisciplinary fashion. Recommendations include continued evaluation of aesthetic perceptions for plant species in urban landscapes and modeling a more consistent framework for …


Cover Crop Effects On Infiltration, Aggregate Stability, And Water Retention On Loessial And Alluvial Soils Of The Lower Mississippi River Valley, Shelby G. Lebeau Dec 2021

Cover Crop Effects On Infiltration, Aggregate Stability, And Water Retention On Loessial And Alluvial Soils Of The Lower Mississippi River Valley, Shelby G. Lebeau

Graduate Theses and Dissertations

Cover crops are a widely considered practice to improve soil health in the form of erosion control, organic matter additions, and improving water-holding capacity. Despite the well-documented benefits, little is known about the effect of cover crops on soils in the Lower Mississippi River Valley (LMRV), an area historically dominated by intensive cultivated agriculture, with soils prone to erosion, and unsustainable aquifer withdrawals for irrigation. The main objective of this study was to evaluate the effects of cover crops [with cover crops (CC) and without cover crops (NCC)] on near-surface soil physical/chemical- and infiltration-related properties, aggregate stability, and water retention. …


Forced And Unforced Permafrost Changes In The Northern Hemisphere During 1901-2100, Hong Guo Dec 2021

Forced And Unforced Permafrost Changes In The Northern Hemisphere During 1901-2100, Hong Guo

Graduate Theses and Dissertations

Permafrost regions are very sensitive to rapid changes in climate and environment. In recent decades, there has been growing interest to better understand the permafrost degradation over the Northern Hemisphere in the context of human-induced climate change. Understanding permafrost dynamics is not only important for infrastructure but also for environmental protection in cold regions. In-situ permafrost measurements are important for assessing permafrost conditions. However, direct permafrost observations are sparse and asymmetrical in both spatial and temporal coverage. Active layer thickness (ALT) modeling is another approach that can overcome many of these limitations, but the models have large uncertainty in predicting …


Assimilation Of Seasonal Moisture Variability In North America And Asia For The Last Millennium, Chang Liu Jul 2021

Assimilation Of Seasonal Moisture Variability In North America And Asia For The Last Millennium, Chang Liu

Graduate Theses and Dissertations

The seasonal tree-ring chronologies that recorded discrete moisture signal for warm and cool season have been used to reconstruct the North America Seasonal Precipitation Atlas (NASPA) by the point-by-point regression method, and the results indicated that they can fairly reproduce the seasonal precipitation variability in the past. Compared with reconstructions using only paleoclimate proxy data, the paleoclimate data assimilation (PDA) considers both proxy data and climate model output, so the PDA reconstructions are consistent with both the climate signals reflected by the proxy data and the physical mechanisms represented by climate models. Based on the tree rings with discrete seasonal …


Nutrient Sources, Loads And Trends Vary Spatially And Temporally Within The Poteau River Watershed And Lake Wister, Oklahoma, Abbie Lasater Jul 2021

Nutrient Sources, Loads And Trends Vary Spatially And Temporally Within The Poteau River Watershed And Lake Wister, Oklahoma, Abbie Lasater

Graduate Theses and Dissertations

Excess inputs of nutrients and sediments jeopardize drinking water sources, aquatic life habitats, and aesthetic quality of freshwater resources for recreation. The purpose of this dissertation was to analyze long-term water quality trends and loads in the Upper Poteau River Watershed (UPRW) and the Lake Wister Watershed (LWW), and analyze internal phosphorus (P) loads in Lake Wister, Oklahoma. Additionally, this dissertation sought to review the literature for methods of prioritizing subwatersheds for watershed management using watershed models, implement a cost efficient method to remotely monitor streamflow and estimate constituent loads in small-scale watersheds, and finally, to validate the Soil Water …


Investigative Study Of Microalgal And Electrochemical Wastewater Treatment Systems And Modeling Of The Wafer-Enhanced Electrodeionization Using Supervised Learning, Humeyra Betul Ulusoy Erol May 2021

Investigative Study Of Microalgal And Electrochemical Wastewater Treatment Systems And Modeling Of The Wafer-Enhanced Electrodeionization Using Supervised Learning, Humeyra Betul Ulusoy Erol

Graduate Theses and Dissertations

Wastewater has a serious impact on environment and public health due to its high concentration of nutrients and toxic contaminants. Without proper treatment, excess nutrients discharged in wastewater can cause a damage to the ecosystem such as undesirable pH shifts, cyanotoxin production, and low dissolved oxygen concentrations.

Main objectives of this dissertation work were to investigate i) the biofuel potential of P. cruentum when grown in swine wastewater, ii) the influence of four most commonly used ion exchange resins on the system efficiency and selectivity for the removal of sodium, calcium, and magnesium ions, and iii) the modeling of wafer-enhanced …


The Influence Of Peer Irrigators On The Extensive And Intensive Margin Of Irrigation Techniques, Victoria Bailey May 2021

The Influence Of Peer Irrigators On The Extensive And Intensive Margin Of Irrigation Techniques, Victoria Bailey

Graduate Theses and Dissertations

We examine how irrigation techniques in use by family and friends influence the use and share of land utilizing different irrigation techniques by Arkansas producers. A bivariate sample selection model simultaneously estimates how farm characteristics determine the use and explain the share of a farm that utilizes an irrigation technique. We find that the irrigation techniques in use by family and friends do affect the irrigation techniques a producer uses and the share of acres utilizing different irrigation techniques. A producer with a family or friend that uses end-blocking irrigation is 41% more likely to use end-blocking themselves. Having a …


Economic And Ecosystem Impacts Of Gm Maize In South Africa, Kristiina Ala-Kokko May 2021

Economic And Ecosystem Impacts Of Gm Maize In South Africa, Kristiina Ala-Kokko

Graduate Theses and Dissertations

White maize in South Africa is the only staple crop produced on a widespread commercial basis for direct human consumption using genetically modified (GM) cultivars. Using a combined economic and environmental approach, we estimate the total welfare benefits attributable to GM white maize in South Africa for 2001-2018 are $694.7 million. Food security benefits attributable to GM white maize in South Africa also manifest through an average of 4.6 million additional white maize rations annually. To achieve these additional annual rations using conventional hybrid maize, the additional land required would range from 1,088 hectares in 2001 to 217,788 hectares in …


Climate-Driven Impacts On Himalayan Aquatic Biodiversity: A Case Study Involving Snowtrout (Cyprinidae: Schizothorax), Riri Wiyanti Retnaningtyas May 2021

Climate-Driven Impacts On Himalayan Aquatic Biodiversity: A Case Study Involving Snowtrout (Cyprinidae: Schizothorax), Riri Wiyanti Retnaningtyas

Graduate Theses and Dissertations

Monitoring biodiversity, to include its relative dispersal and contraction, has become a conservation task of great importance, particularly given the catastrophic and ongoing loss of habitat due to climate change. However, the timing, direction, and magnitude of these rates vary across taxa and ecosystems. Predicting specific impacts of climate change can thus be difficult and this, in turn, hampers management action. Metrics are needed to not only quantify contemporary requirements of species, but also predict potential distributions that fluctuate in lockstep with climate.

Montane ecosystems in the Himalayas are highly impacted by climate change, yet remain largely understudied due to …


Managing Climate Change And Weather Extremes For Nature-Based Tourism Organizations In The United States, Siyao Ma May 2021

Managing Climate Change And Weather Extremes For Nature-Based Tourism Organizations In The United States, Siyao Ma

Graduate Theses and Dissertations

Weather and climate serve as profound motivators for tourism travels. Much of the United States (US) has experienced a warming trend as well as higher extreme weather frequency, and the trends are projected to be continued. Consequently, the changing climate is expected to have both direct and indirect impacts on tourism decision-making and travel patterns due to the complex relationship between climate, weather, and outdoor recreation. Climate resources capture the integrated effects of varied meteorological variables that interact with humans in different ways and can be categorized along a spectrum of quantifiable values. This dissertation proposed a Camping Climate Index …


Quantifying The Leaching Of Nutrients And Metals In A Pasture Soil As Affected By Excreta Of Ruminants Fed Alternative Diets, Ian Kennedy May 2021

Quantifying The Leaching Of Nutrients And Metals In A Pasture Soil As Affected By Excreta Of Ruminants Fed Alternative Diets, Ian Kennedy

Graduate Theses and Dissertations

The leaching of nitrate through the soil profile and into adjacent water systems has been a leading cause of water pollution and results in the loss of a valuable nutrient from animal production systems. Forage-based animal production systems may be improved through manipulation of animal diets that incorporate tannins and total polyphenolic compounds with feed, increasing the amount of nitrogen (N) retained by an animal/decreasing rates of digestion and altering the N-containing compounds that are excreted and deposited onto soil. Incorporating the forage legumes sericea lespedeza (Lespedeza cuneate [Dumont de Courset] G. Don) and lablab (Lablab purpurues L.) into the …


Characterization Of Problematic Red Clay Soils In Arkansas For The Purpose Of Onsite Wastewater System Placement, Bailey Darnell May 2021

Characterization Of Problematic Red Clay Soils In Arkansas For The Purpose Of Onsite Wastewater System Placement, Bailey Darnell

Graduate Theses and Dissertations

Distinguishing between red-clay soils that are non-expansive and can reduce and red-clay soils developing in problematic red parent material, which are expansive, but also non-reducing, is key for proper on-site wastewater system placement. The Arkansas Department of Health allows for the placement of on-site wastewater systems in certain red-clay soils that have the potential to reduce, but only in the Ozark Highlands [Major Land Resource Area (MLRA) 116A], which is referred to as the red-soil exception. There is currently little scientific data to support the geographic restriction of the red-soil exception. The objectives of this study were to: i) confirm …


Evaluation Of Nitrous Oxide Emissions From Furrow-Irrigated Rice On A Silt-Loam Soil In Arkansas, Jordan M. Slayden Jan 2021

Evaluation Of Nitrous Oxide Emissions From Furrow-Irrigated Rice On A Silt-Loam Soil In Arkansas, Jordan M. Slayden

Graduate Theses and Dissertations

As the number one rice (Oryza sativa)-producing state in the United States, Arkansas also ranks fourth as the largest user of groundwater. Recently, due to the development of drought- resistant hybrid cultivars, the furrow-irrigated rice production system has become an increasingly popular alternative to traditional flood-irrigated production with respect to conserving groundwater and maintaining yield. However, other environmental parameters, like greenhouse gas emissions, specifically nitrous oxide (N2O), have yet to be evaluated under furrow-irrigated rice. The objectives of this study were to i) evaluate the effects of site position (i.e., up-, mid-, and down-slope) and tillage treatment [i.e., conventional tillage …