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Full-Text Articles in Life Sciences

Near-Surface Soil Property Change Over Time In Two Native Tallgrass Prairies In The Arkansas River Valley, Katie Jansson May 2024

Near-Surface Soil Property Change Over Time In Two Native Tallgrass Prairies In The Arkansas River Valley, Katie Jansson

Crop, Soil and Environmental Sciences Undergraduate Honors Theses

One climate-change mitigation pathway is soil carbon (C) sequestration, which removes carbon dioxide from the atmosphere and stores C in various forms in the soil. Native prairie soils have long been known for their soil C sequestration abilities, but the full extent of their sequestration capacity is not completely understood. This study evaluated the effect of soil depth and soil map unit/prairie combination on changes in various soil properties over time from 2018 to 2022 in the top 20 cm of two native tallgrass prairie soils in the Arkansas River Valley in west-central Arkansas. Soil samples were collected from the …


Examination Of Greenhouse Conditions That Influence Scale Infestation Rates On Begonia, Madeline M. Cusick Apr 2024

Examination Of Greenhouse Conditions That Influence Scale Infestation Rates On Begonia, Madeline M. Cusick

Honors College Theses

Scale insects are common pests within greenhouse and agricultural settings. I quantified scale infestation on Begonia x Richmondensis, also known as the Dragon Wing begonia, within the Armstrong Campus Greenhouse from March to November of 2023. Six different treatments accounted for variations in sunlight, humidity, and temperature within the greenhouse with the goal of determining the insect’s preferred environmental conditions. Morphological comparisons were also made between host plant Dragon Wing begonia and other begonias present within the greenhouse. Analysis indicated a significant difference in scale presence on replicate plants by zone and sunlight treatments, with more plants hosting at least …


Machine Learning-Based Soybean Yield Prediction And Optimizing Lidar-Mounted Uav Efficiency, Leticia Santos Jan 2024

Machine Learning-Based Soybean Yield Prediction And Optimizing Lidar-Mounted Uav Efficiency, Leticia Santos

LSU Master's Theses

The first chapter of this thesis explores the predictive capabilities of random forests algorithm on datasets obtained from field plot experiments on crop management systems in soybean. Furthermore, the chapter presents a complementary analysis of model performance according to dataset sizes and two techniques on how to impute and deal with missing data. Random forests are being compared with standard statistical techniques such as linear regression on a well-structured, information-rich agronomic experiment. The key findings of this chapter includes the best hyperparameters adjustment and the identification of the dataset threshold for optimal algorithms performance. The second chapter has a research …


Assessing Endophyte Frequency Distributions And The Effect Of Epichloë Brachyelytri In The Chemotypic And Genotypic Diversity Of Brachyelytrum Erectum, Rachel Ann Sneed Jan 2024

Assessing Endophyte Frequency Distributions And The Effect Of Epichloë Brachyelytri In The Chemotypic And Genotypic Diversity Of Brachyelytrum Erectum, Rachel Ann Sneed

Theses and Dissertations--Plant Pathology

Seed-transmissible epichloid fungal endophytes are best known for their roles as defensive mutualists in cool-season grasses. Historically, the discovery of fungal endophytes was driven by investigations of plant toxicity to livestock, followed by extensive study of their alkaloids and protection against insects and nematodes. Epichloae can produce four classes of alkaloids: ergot alkaloids, lolines (saturated aminopyrrolizidines), indole–diterpenes, and peramine. It is increasingly evident that these hereditary symbionts have much more diverse chemical profiles both in individual populations and between them. To this end, differences in chemotypic profiles of these symbionts may translate to different evolutionary and environmental advantages across plant …


Environmental Biology Masters Capstone, Antonio Gonzalez-Pita Jan 2024

Environmental Biology Masters Capstone, Antonio Gonzalez-Pita

Regis University Student Publications (comprehensive collection)

Human wildlife interactions (HWI) pose a complex challenge for wildlife managers. Human encroachment into wildlife habitat and the growing number of outdoor recreationists are increasing the frequency of contact and conflict, especially in regions such as the Front Range of Colorado. Geographic information systems (GIS), which use a combination of remote sensing and environmental survey data, allow for predictive spatial analyses of where human wildlife interactions are likely to occur. I used publicly reported observations of moose to create spatial predictive maps in a species distribution model framework. Slope and elevation were shown to be the strongest predictors of HWI, …


Characterization Of Lignin Structural Variability And The Associated Application In Genome Wide Association Studies, Nathan D. Bryant Dec 2023

Characterization Of Lignin Structural Variability And The Associated Application In Genome Wide Association Studies, Nathan D. Bryant

Doctoral Dissertations

Poplar (Populus sp.) is a promising biofuel feedstock due to advantageous features such as fast growth, the ability to grow on marginal land, and relatively low lignin content. However, there is tremendous variability associated with the composition of biomass. Understanding this variability, especially in lignin, is crucial to developing and implementing financially viable, integrated biorefineries. Although lignin is typically described as being comprised of three primary monolignols (syringyl, guaiacyl, p-hydroxyphenyl), it is a highly irregular biopolymer that can incorporate non-canonical monolignols. It is also connected by a variety of interunit linkages, adding to its complexity. Secondary cell wall …


Cellular Control Of Proteostasis, Cytoskeleton Organization, And Polarity Remodeling During Infection-Related Development By The Rice Blast Fungus, Audra Rogers Dec 2023

Cellular Control Of Proteostasis, Cytoskeleton Organization, And Polarity Remodeling During Infection-Related Development By The Rice Blast Fungus, Audra Rogers

Graduate Theses and Dissertations

Understanding the intricate processes underlying fungal infection-related development is crucial for combating plant pathogens. In this study, we investigate the coordination of morphogenetic transitions during plant infection by Magnaporthe oryzae, the blast fungus. We focus on three key aspects: protein quality control, cytoplasmic microtubule organization, and cell-end marker proteins. M. oryzae forms a specialized infection cell known as an appressorium. The proper formation of this cell is crucial for the pathogen to infect a susceptible host. First, we investigate protein quality control mechanisms during infection-related development. Our findings demonstrate that aggregated proteins are sequestered into quality control compartments within conidia …


Evaluation Of Water Hardness And Ph On Soybean And Cotton Insecticide Efficacy, Taylor Davis Dec 2023

Evaluation Of Water Hardness And Ph On Soybean And Cotton Insecticide Efficacy, Taylor Davis

Graduate Theses and Dissertations

Insecticide efficacy often varies by location and year. Many factors can influence an insecticide’s efficacy, but an often-overlooked factor is the quality of water in a carrier solution. Water quality includes many parameters, but two important ones are water hardness and pH. Research has shown that water hardness and pH can affect some pesticides. Multiple experiments were conducted to evaluate the impact of water hardness and pH on insecticide efficacy. Experiments were conducted to evaluate the impact of water hardness and pH on the efficacy and residual control of chlorantraniliprole for the control of corn earworm, Helicoverpa zea (Boddie). Leaf …


Environmental And Agronomic Evaluation Of Struvite In Rice Production Systems, Diego Della Lunga Dec 2023

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 …


Evaluation Of Weed Control Efficacy And Crop Tolerance To Florpyrauxifen-Benzyl Coated Onto Urea, Bodie Lyn Cotter Dec 2023

Evaluation Of Weed Control Efficacy And Crop Tolerance To Florpyrauxifen-Benzyl Coated Onto Urea, Bodie Lyn Cotter

Graduate Theses and Dissertations

Frequent off-target movement occurrences to soybean [Glycine max (L.) Merr.], rice (Oryza sativa L.) injury, and a lack of barnyardgrass [Echinochloa crus-galli (L.) P. Beauv.] control followed the commercial launch of florpyrauxifen-benzyl in 2018. Florpyrauxifen-benzyl is a synthetic auxin, Herbicide Resistance Action Committee (HRAC)/Weed Science Society of America (WSSA) Group 4 herbicide used for postemergence weed control in rice and labeled for application at 30 g ae ha-1. Previous research documented that soybean was susceptible to injury following spray applications of florpyrauxifen-benzyl at less-than-labeled rates, and certain varieties of rice are less tolerant to spray-applied florpyrauxifen-benzyl at 30 g ae …


Management Zone Delineation For Variable-Rate Seeding In Production Soybeans, Ujjwal Sigdel Dec 2023

Management Zone Delineation For Variable-Rate Seeding In Production Soybeans, Ujjwal Sigdel

Graduate Theses and Dissertations

Soybean seeding rate (SR) is selected according to planting date, maturity group, soil properties, and yield goal. Even though one SR is applied in most fields, site-specific adjustments with variable-rate seeding (VRS) technology can help optimize production. The project goal was to determine if VRS could be beneficial to soybean producers in Arkansas. The project objectives were to i) assess planter performance and soybean yield response to five seeding rate treatments, ii) characterize the drivers of yield variability, and iii) create a-posteriori prescription maps for VRS. Five SR treatments (185,000, 247,000, 309,000, 370,000 and 432,000 seeds ha-1) were applied using …


Evaluation Of Oxyfluorfen For Use In Roxy Rice, Casey Hunter Arnold Dec 2023

Evaluation Of Oxyfluorfen For Use In Roxy Rice, Casey Hunter Arnold

Graduate Theses and Dissertations

Mid-southern U.S. rice (Oryza sativa L.) producers are challenged every year to control problematic barnyardgrass [Echinochloa crus-galli (L.) Beauv.] and weedy rice (Oryza sativa L.) because they have evolved resistance to most labeled herbicides. Oxyfluorfen is a Herbicide Resistance Action Committee (HRAC)/Weed Science Society of America (WSSA) Group 14 herbicide that inhibits protoporphyrinogen oxidase within the plant. Currently, there are no HRAC/WSSA Group 14 herbicides labeled for barnyardgrass or weedy rice control in midsouthern rice production. Therefore, oxyfluorfen is being evaluated for barnyardgrass and weedy rice control. Plant breeders at the University of California – Davis were able to breed …


Effect Of Cultural Strategies And Application Technologies On Weed Control In Flooded And Furrow-Irrigated Rice, Noah Hunter Reed Dec 2023

Effect Of Cultural Strategies And Application Technologies On Weed Control In Flooded And Furrow-Irrigated Rice, Noah Hunter Reed

Graduate Theses and Dissertations

Weed control is a major problem that rice (Oryza sativa L.) producers face in the Mid-south every growing season. Restricted use of some rice herbicides has also highlighted the need for more research to be conducted on cultural weed control strategies and application technologies in rice. The aim of these studies was to evaluate rice weed control using various rice row widths, bed widths (irrigation-furrow spacing), rice cultivar selection, and nozzle type selection. Three field experiments were conducted in 2021 and 2022 across four sites at Lonoke, AR, Pine Tree, AR, Rohwer, AR, and Stoneville, MS. In experiment one, as …


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 Dec 2023

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 …


Effects Of Fertigation Versus Palletized Fertilizer On Height And Caliper Growth In Oaks, Zachary M. Davis Oct 2023

Effects Of Fertigation Versus Palletized Fertilizer On Height And Caliper Growth In Oaks, Zachary M. Davis

LSU Master's Theses

The Covid-19 pandemic and ensuing lockdowns led to an increase in revenue and production for green industry products in early 2020. In Study 1. an evaluation of fertigation (liquid feed, quick release) and controlled release fertilizers (CRFs, slow release) were applied to container-grown (7 gallon) live oak (Quercus virginiana) and Nutall oak (Quercus nuttallii) trees (100% Liquid feed, 0% CRF, 67% Liquid feed, 33% CRF, 33% Liquid feed, 67% CRF, 100% Liquid feed, 0% CRF). Live oak trees fertilized with CRFs had increased stem calipers (>30%). Nuttall stem caliper and height were significantly increased by …


Investigating Soil Microbiome Changes During Panax Quinquefolius Cultivation In New Gardens, Pok Man Paul Wan Oct 2023

Investigating Soil Microbiome Changes During Panax Quinquefolius Cultivation In New Gardens, Pok Man Paul Wan

Electronic Thesis and Dissertation Repository

Ginseng (Panax quinquefolius) is susceptible to ginseng replant disease (GRD), resulting in root rot and decreased yield when ginseng is grown in soils previously used for ginseng crops. Although fungal and oomycete pathogens are implicated, GRD is a complex disease and the changes in the soil when initially cultivating ginseng that lead to GRD remain unclear. This thesis reported changes in the soil microbiome from three new gardens in Norfolk County, Ontario over three years starting from seeding with ginseng. Over this period of cultivation, metabarcoding of the V4 region of the 16S ribosomal RNA gene clearly showed …


Isolation And Culture Of Epichloё For Reinfection Of Endophyte-Free Southeastern Wildrye (Elymus Glabriflorus), Bryna Joann Haile Aug 2023

Isolation And Culture Of Epichloё For Reinfection Of Endophyte-Free Southeastern Wildrye (Elymus Glabriflorus), Bryna Joann Haile

Theses and Dissertations

Mutualistic relationships between endophytic fungi and grasses have shown to improve the hardiness of the host. This relationship is common in grasses, including North American native grasses that are important in both forage and grassland ecosystems. Elymus species, such as Canada wildrye (CWR), commonly host the endophytic fungi, Epichloё, while southeastern wildrye (SEWR) may not. In this study, seed of CWR and seed and leaves from local SEWR were assessed for endophyte infection. Infection status was confirmed via histological analysis of seed squashes and leaf peels. Presence/absence of endophyte was determined by scanning for mycelia within seed and between leaf …


Development Of New Cotton Defoliation Sprayer Using Unmanned Ground Vehicle And Pulse Width Modulation Technology, Jyoti Neupane Aug 2023

Development Of New Cotton Defoliation Sprayer Using Unmanned Ground Vehicle And Pulse Width Modulation Technology, Jyoti Neupane

All Theses

Chemical spraying is one of the most important and frequently performed intercultural agriculture operations. It is imperative to utilize appropriate spraying technology as a selection of ineffective one leads to waste of agrochemicals to the non‐target area. Several precision technologies have been developed in the past few decades, such as image processing based on real‐time variable‐rate chemical spraying systems, autonomous chemical sprayers using machine vision and nozzle control, and use of unmanned aerial and ground vehicles. Cotton (Gossypium hirsutum L.) is an important industrial crop. It is a perennial crop with indeterminate growth habit; however, in most parts of the …


Measuring The Physiological Effects Of Methylobacterium Oryzae Foliar Inoculation Onto Salt-Stressed Tomatoes Grown In A Greenhouse Semi-Hydroponic System, Collin Dice Jun 2023

Measuring The Physiological Effects Of Methylobacterium Oryzae Foliar Inoculation Onto Salt-Stressed Tomatoes Grown In A Greenhouse Semi-Hydroponic System, Collin Dice

Master of Science in Integrative Biology Theses

Salinity stress has been shown to improve hydroponic produce quality such as that of tomato but at the trade-off of produce yield. In order to improve demand for hydroponic produce, techniques that improve salinity tolerance could offset declines in yield without altering the improved quality of produce. In two separate trials, we tested whether foliar inoculation of the ACC deaminase-producing bacteria Methylobacterium oryzae CBMB20 improved salt tolerance in tomatoes grown in a semi-hydroponic system using an indeterminate variety exposed to 26mM NaCl (Trial 1) and a determinate variety exposed to 17mM NaCl (Trial 2). We also tested how salinity and …


Biochemical Characterization Of Date Palm (Phoniex Dactylifera L) Seeds Maintained At Microgravity In Outer Space Iss, Shamma Khalid Aldhaheri Jun 2023

Biochemical Characterization Of Date Palm (Phoniex Dactylifera L) Seeds Maintained At Microgravity In Outer Space Iss, Shamma Khalid Aldhaheri

Theses

The UAE’s vision to reach space dates to 1976 when Sheikh Zayed Bin Sultan Al Nahyan met with the National Aeronautics and Space Administration (NASA) Apollo group; this meeting marked the first attempt of UAE to enter the field of space science. The UAE is currently one of the top countries executing space missions and research. This research focuses on the biochemical characterization of date palm seeds that are sent to the International Space Station (ISS) in outer space. The research methodology involves biochemical analysis of seeds maintained under two different environmental conditions-microgravity and standard gravity. In total, 30–45 seeds …


Identification And Quantification Of Allelochemicals Associated With Weed Suppression In Sweetpotato, Varsha Varsha May 2023

Identification And Quantification Of Allelochemicals Associated With Weed Suppression In Sweetpotato, Varsha Varsha

Theses and Dissertations

Mississippi ranks among the leading states in sweetpotato production in the US. However, managing weeds in sweetpotato fields presents a significant challenge, and the limited availability of herbicides labeled for use in sweetpotato makes it even more challenging. The widespread and repeated use of herbicides has led to the development of weed resistance. In addition, herbicides are incompatible with the organic production system. Finding sustainable weed management strategies to provide weed control options for organic cultivation and detain the development of herbicide-resistant weeds under conventional crop production is imperative. The natural chemicals released by the plants, also called allelochemicals, can …


Soil Respiration Measurements Reveal High Retention Of Organic Carbon From Corn Residue Derived High-Lignin Fermentation Byproduct Enabling Sustainable Lignocellulosic Biofuel Production, Michelle Sun Wang May 2023

Soil Respiration Measurements Reveal High Retention Of Organic Carbon From Corn Residue Derived High-Lignin Fermentation Byproduct Enabling Sustainable Lignocellulosic Biofuel Production, Michelle Sun Wang

Dartmouth College Master’s Theses

While 2G biofuel production can utilize non-edible, lignocellulosic feedstocks such as agricultural residues to produce liquid fuel, harvesting crop residues is unsustainable without careful management of the soil underneath. By harvesting a fraction of the crop residues left in the field after harvest, soil health can diminish and critically, the soil organic carbon (SOC) stored in agricultural fields can decrease. Currently, in the most popular 2G process models published, the issue of soil degradation remains unresolved with residue harvest strategies receiving considerable attention in the literature and other SOC management strategies receiving far less. Specifically, the strategy of returning the …


Pasturelands As Natural Climate Solutions: A Socioecological Study Of Tree Carbon And Beef Production Trade-Offs, Bela Starinchak May 2023

Pasturelands As Natural Climate Solutions: A Socioecological Study Of Tree Carbon And Beef Production Trade-Offs, Bela Starinchak

Masters Theses, 2020-current

Forest restoration is the most effective natural climate solution, with the potential to sequester 37% of the carbon dioxide (CO2) needed to reach the Paris climate mitigation goal. Cattle pastures offer an underutilized opportunity to increase global forest restoration efforts, improve biodiversity, and maximize carbon storage through the adoption of management strategies that prioritize the incorporation of trees into pasturelands. However, remote estimations of tree carbon storage in pastoral systems have never been field-verified and their accuracy is unclear. Furthermore, the effect of increased trees on cattle production is understudied across biomes. Lastly, the restoration potential of these …


Deconstructing The Art Of Physical Weed Control, Jordan W. Parks May 2023

Deconstructing The Art Of Physical Weed Control, Jordan W. Parks

Electronic Theses and Dissertations

Farmers adjust physical weed control (PWC) tools to optimize efficacy based on observations of weeds, the crop, and soil conditions. These many variables make PWC research challenging. To study PWC tool settings more closely, we constructed a soil bin with a mobile tool carriage inside of a heated glasshouse. The soil bin was 2 m wide by 12 m long by 1 m high, with a tool carriage that can operate at 0.4 to 19.0 km h-1. Tool angle, spacing, depth, and speed can all be precisely adjusted from the tool carriage and control panel. The goal of …


Influence Of Biochar As A Soil Amendment On Soil Water Content And Wild Blueberry Physiology, Abigayl Novak May 2023

Influence Of Biochar As A Soil Amendment On Soil Water Content And Wild Blueberry Physiology, Abigayl Novak

Electronic Theses and Dissertations

Maine wild (or lowbush) blueberries (Vaccinium angustifolium Ait.) continue to face challenges imposed by climate change. Reduced frequency of precipitation and increased drought conditions have negatively impacted this crop since it resides in sandy soils with limited retention of water and nutrients. The wild blueberry plants growing in water- and nutrient-poor sandy soils are likely to have poor resilience to drought, resulting in a decline in berry yield during drought years. Thus, there is an urgent need to find a drought management solution for wild blueberries. Compared with other drought management practices, such as irrigation systems, mulching, and adopting drought-resistant …


Meta-Analysis Of The Effects Of Endophytes And Their Secondary Metabolites On Herbivory From Insects, Derrick Taylor May 2023

Meta-Analysis Of The Effects Of Endophytes And Their Secondary Metabolites On Herbivory From Insects, Derrick Taylor

All Theses

Endophyte-infected plants have reduced the level of herbivory. The defense to herbivory can vary due to the metabolites in the plant and the method of feeding from the pest. Secondary metabolites produced by the endophytes are mainly alkaloids. The associations between endophytes and some alkaloid groups are studied in greater detail. The lack of research of certain alkaloid groups ultimately means that some alkaloids had more data that could be analyzed. As a result, the alkaloid groups were not evenly represented in the meta-analysis. The meta-analysis analyzed the relative effectiveness of the metabolites or endophytes in each of the articles …


Effect Of Nanobubble-Oxygenated Water For Irrigation Of Sand-Based Golf Course Putting Greens, Eric Deboer May 2023

Effect Of Nanobubble-Oxygenated Water For Irrigation Of Sand-Based Golf Course Putting Greens, Eric Deboer

Graduate Theses and Dissertations

Nanobubbles (NBs) are sub-micron, stable cavities of gas. The properties of NBs theoretically allow long bubble residence times and high gas dissolution rates resulting in the supersaturation of oxygen in water. Adequate soil aeration is a constant concern for producers of agricultural and horticultural crops. Because of their unique properties, NBs have been investigated for oxygenating water used in the irrigation of various agricultural and horticultural crops to increase soil oxygen concentration. Creeping bentgrass (Agrostis stolonifera L.) is the most widely used turfgrass for golf course putting green surfaces. Golf course superintendents use various methods to increase soil oxygen in …


Investigating Effect Of Seed Source And Developing Germination Protocols To Improve Success In Restoration Of Arkansas Tallgrass Prairies, Rhiannon Spencerosa May 2023

Investigating Effect Of Seed Source And Developing Germination Protocols To Improve Success In Restoration Of Arkansas Tallgrass Prairies, Rhiannon Spencerosa

Graduate Theses and Dissertations

American tallgrass prairie has faced losses estimated at 87-98% of original land area since European settlement. Native seeds are often used to supplement struggling or extinct plant populations in tallgrass prairie restoration and establishment sites. Two main considerations in restoration and establishment are from where to source seed and how to obtain high germination rates. In order to determine the effect of seed source, a common garden experiment was performed in Fayetteville, Arkansas in 2022 with five prairie species: Andropogon gerardii (big bluestem), Bouteloua curtipendula (sideoats grama), Panicum virgatum (switchgrass), Schizachyrium scoparium (little bluestem), and Sorghastrum nutans (Indiangrass). Seed was …


Impact Of Cover Crop Species Diversity On Soil Nutrient Availability And Crop Productivity, Amanda Kramer May 2023

Impact Of Cover Crop Species Diversity On Soil Nutrient Availability And Crop Productivity, Amanda Kramer

Masters Theses

Cover crops provide multiple environmental benefits that improve both soil and water quality; however, farmers only utilize them on approximately 5% of harvested U.S. cropland. Low adoption rates are attributed to yield impact concerns, seed and planting costs, and lack of advocacy. This study, which began in October 2019, assessed the effects of nitrogen rate and cover crop diversity on weed biomass, soil coverage, in-situ residue decomposition, soil nitrogen and phosphorus availability, and cash crop yield to better understand the costs and benefits of cover crop adoption at two locations in Tennessee (Milan and Spring Hill). Treatments were replicated 4 …


The Use Of Biological Soil Health Indicators To Quantify The Benefits Of Cover Crops, Alexander Wu Apr 2023

The Use Of Biological Soil Health Indicators To Quantify The Benefits Of Cover Crops, Alexander Wu

Masters Theses

Soils provide many essential functions that support the world. With a decline in soil health, these functions also decrease in efficiency, and can threaten the health of billions of people around the world. Typically, soil health tests do not use biological indicators, however microbes drive and perform vital functions to increase soil health. One way to increase soil health is through the use of cover crops to reduce soil erosion during fallow periods, increasing soil organic matter, as well as collecting nutrients from soil into their biomass. These cover crops are then terminated through various methods such as herbicides, disk …