Life Sciences Commons^™

New York City’S Rising Sea Level And Coastal Erosion: Approaches To Resiliency, Ryder D. Isidro

Student Theses 2015-Present

No abstract provided.

Techniques And Trials In Pteridophyte Conservation And Cultivation, Jessica Bartel

Senior Theses and Projects

With the progressive nature of climate change conditions globally over the past century, there has been increasing focus on conservation of all species, but particularly those already endangered. Over 12,000 species of ferns live on Earth, and they do not produce seeds, so an investigation into their spores and how they reach maturity will allow us to preserve more genetic material in the future for these species. As a result, we investigated ex situ conservation and survivability of in vitro cultured gametophytes of within the genus Dryopteridaceae through herbarium sample germination rates across samples representing a wide age range ( …

Determining The Sap Yield Of Three Maple Species And The Viability Of A Maple Syrup Industry In Northern Utah, Jesse Mathews

All Graduate Theses and Dissertations, Fall 2023 to Present

Maple syrup is an agricultural product produced from the sap exuded by maple trees. All maples can produce sap, and in Utah, the maples include the two native species bigtooth maple (Acer grandidentatum) and boxelder (Acer negundo), and the introduced species Norway maple (Acer platanoides). Little is known about the sap production of these species, and this research aims to examine the volume of sap yield and sugar content of these maples, evaluate the performance of bucket and tubing collection systems, and explore the potential economics of a maple industry in the state. Research …

Processes For Improved Variable Rate Irrigation And Nitrogen Within Potato-Wheat-Wheat Cropping Systems, Elisa A. Flint

All Graduate Theses and Dissertations, Fall 2023 to Present

Proper irrigation and nutrient management are vital for optimal crop production within agricultural fields. Improving irrigation and nutrient application through precision agriculture is necessary to conserve the limited resources available, while improving yield and quality of crops produced through such a system. Variable rate irrigation (VRI) and variable rate nitrogen are systems used to apply water and nitrogen more precisely to agricultural fields to reduce runoff, deep percolation, leaching, and other negative impacts of over application, while providing the optimal rates to produce maximum yields. However, the processes to utilize these systems have proven to be more difficult than expected, …

Clonal Growth And Trait Variation In The Colorado Front Range: The Influence Of Elevation And Ecosystem, Jordan Conley

Master's Theses

Amid global climate change, exploring adaptive strategies among alpine flora, particularly through clonal growth, becomes critical for biodiversity conservation. This study aims to explore the patterns of dominance and distributions among clonal species across environmental gradients in the Colorado Front Range, employing a trait-based comparative analysis to understand the adaptive strategies of alpine flora and their implications for conservation amid rapid climate change. We focused on two species, studying traits like lateral spread, bud count, and bulbil numbers. Advanced statistical methods such as Permutational Multivariate Analysis of Variance (PerMANOVA) and Multi-Response Permutation Procedures (MRPP) were used to evaluate community compositions …

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 …

Comparison Of Private And Public Lab Fertilizer Recommendation Impacts On Field Crop Production And Soil Test Results, Megan Baker

All Graduate Theses and Dissertations, Fall 2023 to Present

There are many sources that farmers utilize to determine fertilizer needs for crops such as private and public labs, crop advisors, and fertilizer dealers. In many cases, these sources provide recommendations for a specific crop that can vary greatly, which can lead to large differences in cost. An experiment was established in 2021 with 12 sites across the state of Utah in alfalfa, small grains, and corn to test and compare fertilizer recommendations from five labs. The recommendations tested were from two public labs (Utah State University and the University of Idaho) and three commercial labs located in the Western …

How Is International Orchid Trade Regulated, And How Effective Are Those Regulations?, Madeline Roubik

Mary Ann Bolton Undergraduate Research Award

When investigating the trafficking of wild species, animals are often considered before plants (Phelps et al. 2015). This is especially detrimental to members of the orchidaceae family, which are victims of an extensive illegal trade. It spans the entire globe but is especially concentrated in Southeastern Asia (Phelps et al. 2015). When regarding legislation, however, orchidaceae species are some of the most protected in the world. International legislation such as CITES restricts the movement of endangered orchidaceae across borders (Hinsley 2018). The 1992 Convention on Biodiversity (Lawson et al. 2019) also has policies regarding international orchid trade. National laws regulate …

Contrasting Nitrogen Sources Impact Nitrogen Use Efficiency And Soil Health Under Silage Corn Production In A Semi-Arid Environment, Phearen Kit Miller

All Graduate Theses and Dissertations, Fall 2023 to Present

Silage corn production challenges sustainable intensification and soil health in semi-arid environments because the entire aboveground biomass is harvested and removed from the field. An irrigated silage corn field study was conducted over a decade comparing nitrogen fertility sources using a complete randomized block design with four treatments: control with no nitrogen fertilizer (control), low ammonium sulfate at 112 kg N ha⁻¹ (AS100), high ammonium sulfate at 224 kg N ha⁻¹ (AS200), and steer manure compost at 224 kg total N ha⁻¹ (compost). Research focused on the impact of these contrasting nitrogen sources on silage corn production, …

Soil Reclamation Strategies In Construction Disturbed Soil, Alexis Koelling

All Graduate Reports and Creative Projects, Fall 2023 to Present

The rapid urbanization occurring in arid environments like the Intermountain West region of the U.S. significantly alters soil conditions. Construction of roads, buildings, and other infrastructure leads to the disturbance of soil structure, nutrient depletion, and reduced fertility. This research addresses the need for sustainable soil management practices that may restore soil health post-construction. In this study, the effectiveness of various soil amendments and application methods on specific soil parameters and turfgrass establishment in construction-disturbed soils was evaluated. The study highlights the critical role of soil amendments, particularly municipal solid waste (MSW) compost, in improving soil quality and plant growth. …

Sustainable Fertilizer Management Practices For Container Nursery Production, Saroj Burlakoti

All Graduate Theses and Dissertations, Fall 2023 to Present

Growing nursery plants in containers requires a timely supply of mineral nutrients for optimum growth. However, there is a misconception among growers that the application of higher doses of fertilizers hastens plant growth; instead, it can lead to runoff and leaching loss of nutrients. Reducing fertilizer application while sustaining healthy plants can not only negate environmental consequences but also save fertilizer costs. For example, two ground covers, Lysimachia nummularia (creeping jenny, moneywort) and Vinca minor 'Bowles' (periwinkle), can be grown for three months by applying 6 mg/L of phosphorus (P) as reduction of P to single application of 6 mg/L …

Nutrient Management Of Cannabis In Controlled Environments, Julie A. Hershkowitz

All Graduate Theses and Dissertations, Fall 2023 to Present

Cannabis has been cultivated for millennia as a multipurpose crop for food, fiber, and medicine. Secondary metabolites called cannabinoids, including cannabidiol (CBD) and the psychoactive Δ-9 tetrahydrocannabinol (Δ-9 THC), are responsible for the medicinal properties of cannabis. The intoxicating nature of THC resulted in legislation prohibiting the possession and production of cannabis within the United States during the 20^th century. As a result, research programs on cannabis production were halted at most institutions. In recent years, cannabis production has become widespread within the US as a result of increasing legalization. However, modern cannabis production nutrient management programs often include …

Morphological And Physio-Biochemical Responses And Gene Expression Analyses Of Landscape Plants Under Salinity Stress, Asmita Paudel

All Graduate Theses and Dissertations, Fall 2023 to Present

Soil salinity is a significant global issue that adversely impacts the growth and development of landscape plants. One of the effective strategies to prevent salinity damage to landscape plants is to cultivate species that are tolerant to the prevailing salinity levels. Salinity tolerance varies among plant species and cultivars. Therefore, this research aimed to investigate the salinity tolerance of nine landscape plants [Albizia julibrissin (mimosa tree), Arctostaphylos uva-ursi (kinnikinnick), Cercocarpus ledifolius (curl-leaf mountain mahogany), Cercocarpus montanus ‘Coy’ (alder-leaf mountain mahogany), Penstemon barbatus ‘Novapenblu’ (rock candy blue^® penstemon), Penstemon strictus ‘Rocky Mountain’ (rocky mountain beardtongue), Punica granatum ‘Wonderful’ (pomegranate), …

What's In A Name? Plant Naming As Cultural Artifact And Story In The Midwestern United States, Sophie Wesseler

Undergraduate Theses

This project sought to collect and contextualize the historical and contemporary names given to plants by inhabitants of the Midwestern United States, understanding plant names as cultural artifacts that can offer insight into the communities in which they were created and evolved. Formatted as a series of entries, this collection gathered these names and contextualized them within other artifacts of cultural significance, such as art or poetry, and alongside historical research on their origins and cultural environments. Examining plant names through the fields of linguistics, semiology, anthropology, cultural studies, taxonomy, and ethnobotany, this work traces the names of various plants …

Clonal Plants' Traits And Responses Following Fire Disturbance In Ponderosa Pine Ecosystems In The Colorado Front Range, Raymond Erskine

Master's Theses

Mountain ecosystems are currently experiencing increasing impacts of disturbances (e.g., wildfire) due to global changes in climate and land use, leading to significant changes in vegetation composition and landscape dynamics. Clonal plants, characterized by their vegetative reproduction strategies, offer a range of ecologically important traits to cope with disturbances. However, clonality is often excluded in studies of post-fire vegetation dynamics in mountain ecosystems, and our knowledge of the ability of clonal plants to respond to differing disturbance regimes is limited. Therefore, I examined the response of understory vegetation following fire disturbance in burned and unburned ponderosa pine stands of the …

Effects Of Uv Filter Pollutants On The Growth Of Cucurbits And Possible Implications For Humans, Leia Staples

Undergraduate Theses

One main area of concern is the use of personal care products and pharmaceuticals in society and their long-term persistence when released into the environment (Chaturvedi et al. 2021). Cucurbits, however, are well-known for taking up pollutants (Namiki et al. 2013, Christou et al. 2019, Komives et al. 2009), so it essential to ensure that these pollutants do not negatively affect growth or productivity of plants. These plants are particularly useful in society because they have many health benefits and are consumed regularly by humans. While much research has been done on how much of the pollutant travels throughout the …

Ammonium Chemotaxis In Chlamydomonas Reinhardtii, Gabela Nelson

LSU Doctoral Dissertations

Analysis of ammonium chemotaxis in Chlamydomonas reinhardtii is largely hindered, compared to that of phototaxis, despite equal importance on flagellated microalgal physiology. A major contribution of this shortfall is the lack of proper assay method. We developed a simple Petri dish assay method in which light is homogenously exposed while patterns of the cellular migration are tracked with a function of time. Using the method, new findings were revealed. First, this research presented that a strain lacking the eyespot organelle required for light gradient-sensing exhibits similar chemotactic behavior compared to a wild-type strain, suggesting Chlamydomonas sense an ammonium gradient not …

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 …

The Evolution And Development Of Awns In The Grass Subfamily Pooideae, Erin L. Patterson

Doctoral Dissertations

This research focuses on a specific example of replicated evolution: the grass awn. Awns are typically extensions of the lemma, but may also appear on glumes or paleas. The lemma is a leaf-like organ on the exterior of the grass flower, the glumes are a pair of bracts subtending the basic unit of grass inflorescences, the spikelet, and the palea is the floral organ opposite the lemma. Awns are often described as "hair-" or "bristle-" like, but appear in many different shapes. Many awns are “twisted & geniculate", in which the awn has two sections, a lower twisted column, and …

Identification And Characterization Of Isoflavone Reductase Family Members In Soybean, Negin Azizkhani

Electronic Thesis and Dissertation Repository

Soybean’s yield is threatened by Phytophthora sojae, a pathogen responsible for stem and root rot disease. Glyceollins, unique antimicrobial agents specific to soybeans in partially preventing P. sojae infection, are derived from the isoflavonoid branch of the general phenylpropanoid pathway. One pivotal enzyme exclusively involved in glyceollin synthesis in soybean is the isoflavone reductase (GmIFR), which catalyzes the 2'-hydroxydaidzein conversion to 2'-hydroxy-2,3-dihydrodaidzein as a precursor for glyceollin biosynthesis. To comprehensively identify all members of the GmIFR gene family within the soybean genome, keyword and blast protein searches were conducted, identifying 98 putative GmIFRs. Among these candidates, …

Halosulfuron Plus Prosulfuron And Propanil Interactions For Weed Control In Louisiana Rice Production, John A. Williams

LSU Master's Theses

A greenhouse study was conducted on November 18, and December 2, 2020 at Louisiana State University in Baton Rouge, Louisiana to evaluate the interaction between a pre-packaged mixture of halosulfuron plus prosulfuron mixed with propanil for alligatorweed control. Antagonism occurred when halosulfuron plus prosulfuron at 55 g ha-1 was mixed with propanil at 2,242 g ha-1 at all evaluation dates and antagonism was also observed with halosulfuron plus prosulfuron at 83 g ha-1 mixed with propanil at 2,242 g ha-1 at all evaluation dates except 14 DAT with observed controls of 69 to 77% compared with expected controls of 94 …

Automated Tree Mortality Detection Using Ubiquitously Available Public Data, Michael T. Huggins

Master's Theses

Understanding the dynamic interplay between fire severity, topography, and tree mortality, is crucial for predicting future forest dynamics and enhancing resilience against climate change-induced wildfire regimes. This thesis develops a multi-sensor approach for automated estimation of tree mortality, then applies it to examine trends in tree mortality over a six-year period across a fire affected study site in the Trinity River basin in Northern California. The Random Forest model uses publicly available USGS 3D Elevation Program Lidar (3DEP) and NAIP imagery as inputs and is likely to be easily adaptable to other landscapes. The model had a Receiver Operating Characteristic …

Applicability Of Using Bio-Receptive Concrete For Building Facades In Egypt, Gina Roupheil

Theses and Dissertations

The significant increase in carbon dioxide emissions caused by the construction industry is detrimental to our planet. This is rapidly increasing with the urbanization of cities that is gradually taking its toll on the available green spaces, which help in balancing such emissions. Recently, researchers have been trying to make use of bio-receptivity to create biomaterial systems that could be spread on building envelopes and support the growth of small plant species and microorganisms to establish on. Out of those materials, comes the concrete as a promising material for bio-colonization.

Within this context, this study aims at investigating the applicability …

The Ecological Responses To Hydroperiod Of Wetland Plant Species Determined By Manipulated Soil Surface Elevation (Marsh Organs), Brandon Wolff

LSU Master's Theses

As sea level rise, subsidence, and abandonment of natural deltaic processes due to a highly engineered Mississippi River continue to threaten Louisiana’s coastal wetlands, the need for a system-wide understanding of natural wetland land-building and preservation processes has never been greater. A key component of any wetland is the ever-changing water environment that periodically floods and dries the marsh platforms. The flooding depth, duration, and frequency, known as the hydroperiod, along with salinity and soil fertility are key determining factors of vegetation and marsh types at a particular location. Different types of vegetation will have different growth characteristics such as …

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 …

Evaluation Of Winter Cereal Cover Crops Across Nitrogen Management Stragies For No-Till Corn Production, Robert Nalley

Theses and Dissertations--Plant and Soil Sciences

Rye (Secale cereale L.) is the most popular winter cereal cover crop utilized before corn, but wheat (Triticum aestivum L.) and barley (Hordeum vulgare L.) may provide a comparable value due to their similar fibrous root systems. Despite the benefits associated with winter cereal cover crops, drawbacks are possible for the subsequent corn crop. A field study was conducted with three site-years in Kentucky to measure the impact of the three winter cereals across nitrogen (N) management strategies. Wheat produced the most biomass compared with barley or rye cover crops. Wheat and rye needed approximately 100 more …

Utilizing Soil Sensors To Assess Soil Health And Investigating Cover Crops Impact On Methane Emission, Shailesh Pandit

Electronic Theses and Dissertations

Soil health is influenced by climate change, cultural practices, topography, crop rotations, cover crops, soil parent materials, and soil biota. Interactions between these factors can improve or reduce soil health. This thesis investigates two topics, using soil sensors to provide a rapid assessment of soil health, and the impact of cover crops on soil biological activity and greenhouse gas emissions. Chapter 1 explores the use of two types of sensors to measure apparent electrical conductivity (ECa) and provides examples on the use of these sensors. Even though both sensors measure ECa using different processes, they provide useful information about temporal …

Integrating Early Season Clover Cover Crops As A Living Mulch In Broccoli And Transitional Organic Winter Squash Production In Eastern South Dakota, Alexis Rose Barnes

Electronic Theses and Dissertations

Managing weeds, improving soil health, and reducing the use of plastic mulch continue to be priorities for South Dakota vegetable farmers. Farmers have expressed an interest in integrating cover crops into their farm systems. Clover cover crops used as a living mulch within and along cash crop rows may aid in weed suppression, nitrogen fixation, and prevent soil erosion. However, prior research has shown challenges of incorporating living mulch due to yield decreases. Research conducted in 2022 and 2023 in eastern South Dakota investigated the effects of four clover and four in-row soil management treatments on broccoli and organic winter …

Nitrogen Application Timing And Cereal Rye (Secale Cereale L.) Cover Crop Influence Greenhouse Gas Emissions, Graig Reicks

Electronic Theses and Dissertations

Dryland contributions to greenhouse gas (GHG) emissions are increased by N fertilizer applications and high soil water contents. Fertilizer timing and spring growth of cover crops prior to cash crop planting were investigated in separate studies to examine impacts on overall GHG emissions using a near continuous measurement system. There was a significant interaction between N fertilizer rate (0 vs. 224 kg N ha-1 surface-applied as urea) and application date (p= 0.01) for CO2 emissions. This interaction occurred because N fertilizer increased CO2 emissions by 35% for the 21 d interval following early spring application. When application was delayed until …

Portable X-Ray Fluorescence Spectrometry For Sensing Salinity And Sodicity In Glacial Northern Great Plains Soils With Machine Learning Models, Adam Devlin

Electronic Theses and Dissertations

Saline and sodic soils are an increasing concern across the Northern Great Plains (NGP) due to factors of climate change and land management that are drawing geologically derived salts to the land surface. Traditional laboratory assessments, such as electrical conductivity (EC) and sodium adsorption ratio (SAR), are time and resource consumptive. Portable X-ray fluorescence (PXRF) may be a viable proximal sensing alternative, as it is able to provide elemental data in minutes, in situ or ex situ, and can directly quantify salinity-associated elements like Ca, Mg, and S. PXRF paired with predictive models has proven useful for a range of …