Plant Sciences Commons^™

Reintroducing Hemp (Rongony) In The Material Palette Of Madagascar: A Study On The Potential Of Hemp Clay Components And Its Impact On Social And Ecological Communities., Henintsoa Thierry Andrianambinina

Masters Theses

When mentioning the word hemp, especially in the local language of Madagascar, the literal translation does not set it apart from marijuana, as they are both called “rongony” - creating the stigma around hemp as the negative stereotype of marijuana. However, the material has been used by the ancestors of Madagascar, as well as across cultures, in its fibrous form to produce fabrication like textile goods and packaging. During colonization, the prohibition of hemp intensified, and since then, any activity related to either of these plants is prohibited and will end in severe punitive measures. This thesis explores the strengths …

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

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 …

Does Invasion Science Encompass The Invaded Range? A Comparison Of The Geographies Of Invasion Science Versus Management In The U.S., Lara Munro

Masters Theses

Biases in invasion science lead to a taxonomic focus on plants, particularly a subset of well-studied plants, and a geographic focus on invasions in Europe and North America. Geographic biases could also cause some branches of invasion science to focus on a subset of environmental conditions in the invaded range, potentially leading to an incomplete understanding of the ecology and management of plant invasions. While broader, country-level geographic biases are well known, it is unclear whether these biases extend to a finer scale and thus affect research within the invaded range. This study assessed whether research sites for ten well-studied …

Influence Of Living Plant Roots And Mycorrhizal Hyphae On Soil Hydraulic Properties, Katelyn M. Marcacci

Masters Theses

The interrelationships between vegetation, soil, and water are fundamental in evaluating the projected impacts of global climate change. Many predictive models require soil hydraulic parameters as inputs. As most hydraulic parameter datasets are for repacked soil, the influence of vegetation on hydraulic parameters is not thoroughly understood. Living roots and mycorrhizal fungi cause physicochemical alterations in soils. Quantifying how vegetation influences soil hydraulic parameters is necessary to more accurately simulate soil water dynamics in climate models.

Laboratory experiments were conducted to test if the presence of roots and roots inoculated with mycorrhizal fungi have a significant effect on the saturated …

Processes, Patterns, And Predictions Of Soil Moisture Variation In Upland And Peatland Cranberry Farms In Massachusetts, Rebecca Brennan

Masters Theses

The American Cranberry (Vaccinium macrocarpon Ait.) represents a vital sector of the economy of southeastern Massachusetts. Due to the hydrogeological and edaphic characteristics of peatlands, variations in soil drainage and soil moisture represent major management challenges for growers in Massachusetts. An emerging trend of upland (mineral soil) cranberry farms planted with new hybrid cultivars has the potential to enhance the profitability and long-term viability of cranberry production in Massachusetts. However, sparse data exist on soil moisture characteristics of peatland and upland cranberry farms. The purpose of this research was to elucidate the differences in soil moisture between upland and …

Evaluation Of The Symbiotic Relation Between Endophyte And Poplar Trees Exposed To Landfill Leachate, Catalina Vega Hurtado

Masters Theses

“The contamination of soil and groundwater from leachate leakage from landfill has turned, nowadays, into a global public issue. One of the main concerns about this pollutant is the potential threat to human and ecosystem health. The current research studied endophyte bacteria in association with poplar trees (Populus sp.), as a method of bioremediation of landfill leachates. The objective of the project was to identify treatment strategies that may improve plant performance (survival rates, plant fitness, and degradation efficacy) with the purpose of being implemented in phytoremediation plots, aimed to intercept and treat landfill leachate, before the contamination of watershed. …

Arboriculture Safety Around The World, Jamie Lim

Masters Theses

Arboricultural work is inherently dangerous, with more serious injuries and fatalities than most other professions. Safety standards exist in some jurisdictions, but it is unclear how many standards exist, how they compare to one another, and whether (and how many) jurisdictions share standards. To establish a baseline understanding of these issues, my objectives were to (i) develop a database of existing standards, (ii) identify the most frequently occurring safety topics and (iii) describe similarities and differences in safety topics among standards from different countries. I worked with a variety of contacts and traditional university library resources to identify, obtain, analyze, …

Variation In Leaf Morphology Of An Alpine Shrub Community Along Environmental Gradients, Abdulssalam Khafsha

Masters Theses

Mountains represent complex environment gradients which strongly affect local temperature regimes and rainfall. These changes in climate conditions drive a diversity of plant responses. As alpine environments are expected to change dramatically in response to climate change, understanding plant responses to environmental variation is critical in these environments. Although they are a critical component of alpine communities, the environmental responses of shrubs have been much less examined than trees, representing an important knowledge gap. Leaves, as the primary photosynthetic organs on plants, would be expected to respond strongly to local climate conditions. In this study, I documented how the leaf …

Impacts Of Plant-Microbe Interactions On Seedling Performance In A Riparian Forest Invaded By Lonicera Maackii, Taylor E. K. Strehl

Masters Theses

Soil microbes have profound impacts on plant growth and survival and can either promote or inhibit plant dominance. Exotic plants are often strongly invasive because they have escaped their natural enemies, potentially including antagonistic soil microbes. I examined how the invasive shrub Lonicera maackii and a common native tree, Acer negundo, responded to soil microbial communities to determine the role of soil microbes in regulating invasion success. This was done by growing both species with microbes from invaded (L. maackii) and uninvaded (A. negundo) soils collected from three locations within a riparian forest. Seedlings were …

Plants, Parasites, And Pollinators: The Effects Of Medicinal Pollens On A Common Gut Parasite In Bumble Bees, George Locascio

Masters Theses

Declines in several pollinator species are due to a variety of factors, including pathogens. Incorporating pollinator-friendly plant species into wild and agricultural habitats could reduce the stress of pathogens if food sources act medicinally against pathogens. Previous research demonstrated one domesticated sunflower cultivar (Helianthus annuus) can dramatically reduce a gut pathogen (Crithidia bombi) of the common eastern bumble bee, Bombus impatiens. To ascertain the breadth of this medicinal trait, we tested whether pollen from several H. annuus cultivars and four relatives could also reduce C. bombi infections in B. impatiens. We also investigated whether …

Co-Product Potential Of Algae Biocake, Elizabeth J. Nixon

Masters Theses

Society needs to find replacements for fossil fuels, which are finite resources that may be fully depleted within a few generations. While solar and wind have great potential as alternative energy sources, they are unlikely to completely replace all of the current fuel sources, particularly liquid fuels. Plant biomass has great potential for this market, and is already used in many forms for heat energy (e.g. direct combustion). However, the bulk density of important bioenergy crops, particularly grasses, is often low, which necessitates the use of binders in densification strategies. In the present study, waste algae biocake from a proprietary …

Testing The Temporal Stability Of The Climate Response Of Tree Species At Norris Dam State Park, Tennessee, U.S.A., Allison Elizabeth Ingram

Masters Theses

Temporal stability of the climate-tree growth relationship means that over time, tree species were responding to a specific climate variable and continue to respond to that variable into the present. The stability of this response is important to test prior to attempting to reconstruct past climate. In this study, I sampled oaks (white oak = Quercus alba L. and chestnut oak = Quercus montana Willd.) and pines (Virginia pine = Pinus virginiana Mill. and shortleaf pine = Pinus echinata Mill.) growing in Norris Dam State Park in eastern Tennessee and tested the temporal stability of these species and their potential …

Impacts Of Biofumigation And Anaerobic Soil Disinfestation On Strawberry Production, Jennifer Renee’ Wheeler

Masters Theses

Due to the phase-out of methyl bromide, there is a need for alternative, nonchemical fumigation treatments in strawberry production. Anaerobic soil disinfestation and biofumigation are two non-chemical methods for controlling soilborne plant pathogens of strawberry. This study was designed to observe strawberry fruit nutrition and soil volatiles of a strawberry field being treated with biofumigation treatments, anaerobic soil disinfestation treatments, and a combination of the two alternative methods. A trial was conducted with 11 pre-plant soil-incorporated treatments arranged in a randomized complete block design with 6 rows (blocks). Biofumigation treatments consisted of deactivated mustard meal, deoiled mustard meal, mustard pellets, …

Rare Occurrences Of Free-Living Bacteria Belonging To Sedimenticola From Subtidal Seagrass Beds Associated With The Lucinid Clam, Stewartia Floridana, Aaron M. Goemann

Masters Theses

Lucinid clams and their sulfur-oxidizing endosymbionts comprise two compartments of a three-stage, biogeochemical relationship among the clams, seagrasses, and microbial communities in marine sediments. A population of the lucinid clam, Stewartia floridana, was sampled from a subtidal seagrass bed at Bokeelia Island Seaport in Florida to test the hypotheses: (1) S. floridana, like other lucinids, are more abundant in seagrass beds than bare sediments; (2) S. floridana gill microbiomes are dominated by one bacterial operational taxonomic unit (OTU) at a sequence similarity threshold level of 97% (a common cutoff for species level taxonomy) from 16S rRNA genes; …

Long-Term Impacts Of Conservation Management Practices On Soil Carbon Storage, Stability, And Utilization Under Cotton Production In West Tennessee, Candace Brooke Wilson

Masters Theses

Biogeochemical cycling of soil carbon (C) is heavily influenced by conservation agricultural (CA) practices. This study examined SOC stability under three CA practices: reduced nitrogen (N) fertilizer application rate, cover cropping, and zero-tillage implemented for 31 years. Respiration rates measured from a 602-day incubation period were fitted to a double-pool first order exponential model of SOC decomposition. The active [respired] SOC pool showed distinct differences between applications of reduced (34N kg ha^-1 [-1]) and high fertilization rates (101N kg ha^-1) combined with tillage, and suggest that high fertilizer applications with conventional tillage allocated more C into a …

Volatile Profiles And Resistance To Herbivory In Eastern Hemlock, Elizabeth A. Mckenzie

Masters Theses

Eastern hemlock hosts the hemlock woolly adelgid, an introduced sap-feeding insect that causes rapid deterioration of the host. Like most conifers, eastern hemlock produces a variety of constitutive and induced defenses, primarily terpenoids. To explore the relationship of terpenoid defenses with adelgid infestations, we artificially infested hemlocks at a forest site and a plantation site, and compared their terpenoid concentrations to those in control trees. Infested trees showed lower terpenoid concentrations than control trees, suggesting that eastern hemlock not only fails to induce production of terpenoids in response to adelgid infestation, but becomes less able to produce carbon-based defenses due …

A Vegetation History From Emerald Pond, Great Abaco Island, The Bahamas, Based On Pollen Analysis, Ian Arthur Slayton

Masters Theses

Emerald Pond (26° 32' 12" N, 77° 06' 32" W) is a vertical-walled solution hole in the pine rocklands of Great Abaco Island, The Bahamas. In 2006, Sally Horn, Ken Orvis, and students recovered an 8.7 m-long sediment core from the center of the pond using a Colinvaux-Vohnout locking piston corer. AMS radiocarbon dates on macrofossils are in stratigraphic order and indicate that the sequence extends to ca. 8400 cal yr BP. Basal deposits consist of aeolian sands topped by a soil and then pond sediment, suggesting that the site began as a sheltered, dry hole during a Late Pleistocene …

Comparative Ecophysiology Of American Chestnut Under Different Planting Treatments On Reclaimed Mine Sites, Christopher Ryan Miller

Masters Theses

American chestnut was once an abundant species that dominated the Eastern U.S. deciduous forests. Although this species is currently functionally extinct due to the chestnut blight, researchers are working on blight-resistant hybrids in hopes of restoring the species. As one potential vector for chestnut reintroduction and dispersal, the reclamation of mine sites are being considered. Recent research has found that reforestation efforts on these reclaimed mine sites provide productive tree growth while also complying with mine-reclamation laws. Understanding how American chestnut performs physiologically on mine sites will aid in the restoration of this species and reclamation of mine sites.

The …

Classification And Fertility Of Soils In The Big South Fork National River And Recreation Area Based On Landscape Position And Geology, Ryan H. Blair

Masters Theses

The Big South Fork National River and Recreation Area encompasses more than 50,585 hectares (125,000 acres) of the Cumberland Plateau along the border of Tennessee and Kentucky. Highly dissected and steep terrain have made accessibility to much of the park limited, thus little work has been done to investigate the formation of these soils. Seven native soil profiles were selected for chemical and physical analysis representing Pennsylvanian-aged acidic sandstone and shale geology and landforms. The objectives of this study included the characterization of selected native profiles by physical and chemical analysis, as well as classification using US Soil Taxonomy, to …

Vegetation And Tree Survival In A Savanna Restoration Project, Vermilion County, Illinois, Mary Claire Hruska

Masters Theses

This study involved pre-burn and post-burn inventories of herbaceous and woody vegetation, a post-burn tree survival survey, the development and implementation of a management plan for the savanna restoration site and the development of general guidelines for savanna restoration. An herbarium collection was made, 242 species representing 64 families were found on the site.

There were several significant changes in the density and frequency of vegetation after the burn. The following herbaceous species increased significantly in frequency: Agalinis tenuifolia (Vahl.) Raf, Ambrosia artemisiifolia L., Carex spp., Cassia fasciculata Michx., Desmodium glabellum (Michx.) DC., Dichanthelium acuminatum (Sw.) Gould & Clark var. …

Effects Of Lake Management On Chemical, Physical, And Phycological Characteristics Of A Hypereutrophic Reservoir, Kaye J. Surratt

Masters Theses

Lake Charleston is a 1.1 billion gallon capacity side channel reservoir which was constructed in 1982 as a public drinking water supply for the City of Charleston in Coles County, Illinois. Past studies of the lake indicated an increase in eutrophication and the capacity to support large algal populations. Recent lake management practices include copper sulfate applications as an algicide and aeration to reduce flavor and odor.

In order to assess present lake status and to evaluate the effectiveness of lake management practices, two lake sites were sampled on a weekly basis from May to October, 1989. Chemical, physical, and …

Vegetation Changes In Four Study Areas At Indiana Dunes National Lakeshore, Kathryn Ann Kerr

Masters Theses

The sampling transects at Indiana Dunes were established to show the pre-burn condition of the vetetation and to monitor the long term effects of burning. However, one year of monitoring showed changes in vetetation that further substantiate the need for the burning program.

Miller Woods (Transect A) has burned frequently in recent years. The one year without fire showed little change in the herbaceous layer. The few notable herbaceous changes might indicate a transition to a more mesic community, but should be viewed skeptically because of the wet season in 1982.

Nearly half of the small shrub species at Miller …

The Effects Of N-Serve On The Availability Of Urea And Ureaformaldehyde Nitrogen On Lolium Perenne L., Ronald E. Schroll

Masters Theses

Laboratory experiments were conducted to determine the effect of "N-Serve" (DOW) on the availability of urea nitrogen and the subsequent greening effect on perennial ryegrass (Lolium perenne L.) seedlings as compared to the availability of nitrogen and subsequent greening from a controlled release ureaformaldehyde fertilizer. A low organic matter sandy loam soil and a high organic matter clay loam soil were used in this study. Soil treatments of urea and ureaformaldehyde fertilizers were applied and incorporated at concentrations of 0, 25, 38, and 50 ppm-N. N-Serve at concentrations of 0.25, 0.50, and 1.0 ppm active ingredient were applied and …

Leaching Of An Acetanilide Herbicide, Cp55097 In Soil Columns, Regina K. Higgins

Masters Theses

The leachability of the acetanilide herbicide, CP55097 was determined using a soil column system. This herbicide, which is used as a preemergent against certain grasses and broadleaf weeds, was leached through four different soils (sandy clay, sandy loam, sandy clay loam and clay loam) using the following procedure. Plastic columns consisting of 8 rings (2 in. dia. x 1 in.) were assembled and their bottoms covered with cheesecloth. They were then filled with soil and prewetted with water to attain field capacity. Herbicide concentrations equalling 0, 1, 3, 6 lb/A were pipetted onto the soil surface and 0, 1, 2, …

The Effects Of Sulphur Dioxide On Selected Hepatics, Steven L. Gatchel

Masters Theses

Extensive studies have been reported on the air pollutant sulphur dioxide (SO₂), and its effects on vascular and nonvascular plants. It has been shown to interrupt normal physiology, metabolism, reproduction, and alter the plant’s morphology.

Of the cryptogams, lichens have been extensively used as biological indicators of air pollution. More recently, bryophytes have been shown to be as sensitive to contaminates as lichens, and may exhibit responses to the pollutant similar to those of vascular and nonvascular plants. The threshold sensitivity of these cryptogams is about 0.5 ppm over a 12 hour period. However no study to date …