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Comparing Macroinvertebrate Total Abundance And Total Biomass On Five Substrate Types From Upstream To Downstream On The North Branch Of The Au Sable River, Paul David Dingman

Masters Theses

The North Branch of the Au Sable River is located in the northern lower peninsula of Michigan and is known for prolific hatches of Ephemeroptera (mayflies), Trichoptera (caddisflies), and Plecoptera (stoneflies). Macroinvertebrates play an important role in processing and recycling organic material in rivers and are a valuable food source for trout. In 2018, anglers were reporting catching fewer numbers of brook and brown trout (Salmo trutta and Salvelinus fontinalis). The Michigan Department of Natural Resources (MDNR) determined significantly lower abundance than the historical average. We hypothesized that trout abundances were lower due to a lack of prey …

Mutable Landscapes: Diversity Through The Lens Of The Earth's Biomass, Ilya Iskhakov

Masters Theses

This thesis explores conditions of mutability in the landscape through the lens of the Earth’s biomass, particularly the living beings whose systemic, functional and aesthetic values are misrepresented or undervalued. Relegated to the abandoned, derelict and forgotten landscapes, the presence of these living things has often come to represent decay, blight, lack of resources, and care. However, in the light of the global environmental crisis and in search of viable solutions to clean up the environment and curb greenhouse gas emissions, it has become apparent that the spontaneous, opportunistic qualities of these living beings can provide unparalleled opportunities to do …

The Gene Expression Patterns Of Phanerochaete Chrysosporium And Trametes Versicolor On Diverse Lignocellulosic Feedstocks, Noor Osama Alabbasi

Masters Theses

Plant biomass is considered to be an important future starting material for fuels and chemicals, thereby decreasing our reliance on fossil fuels. While direct combustion continues to be a source of fuel, the generation of liquid fuels from plant biomass for transportation has proven to be challenging. Among the limiting factors for conversion of this material to biofuels is the recalcitrant nature of lignocellulose, the primary component of non-starch plant biomass. A strategy to overcome this dilemma is to directly or indirectly use the enzymes from white-rot fungi, which have evolved a unique ability to deconstruct lignocellulose. However, the biochemical …

A Cloning Strategy For Expression Of Fungal Hemicellulases In Plant Systems, Amer Alrudayan

Masters Theses

Lignocellulosic biomass is notoriously difficult to deconstruct into lignin, hemicellulose, and cellulose fractions without the use of biochemical, chemical, and/or mechanical pretreatments. These pretreatment strategies add operational cost and in some cases produce hazardous waste that poses health and safety risks. Direct biological pretreatment from biomass-degrading bacteria and fungi may significantly reduce the costs and risks associated with these traditional strategies due to the innate ability of these organisms to modify plant cell walls. An additional measure that could further reduce the expenses associated with lignocellulosic biomass fractionation is genetic modification of the lignocellulosic feedstocks, which can be accomplished by …

Computational Fluid Dynamic Modeling Of Catalytic Hydrous Pyrolysis Of Biomass To Produce Refinery-Ready Bio-Crude Oil, Ross Wesley Houston

Masters Theses

The growing world population continually increases the demand for energy. Currently, the main source of energy production is fossil fuels, which are harmful to the environment and are finite. An exploration of renewable energy to supplement or replace fossil fuels is of great importance. Modern techniques for producing renewable bio-oil consist of converting biomass into bio-oil through pyrolysis, but unfortunately, pyrolysis oil has quality issues (e.g., high oxygen content, viscosity, chemical instability). Therefore, upgrading is necessary to improve quality. Hydropyrolysis is a state of the art technique to deoxygenate bio-oil during pyrolysis to produce petroleum quality bio-oil. A major issue …

A Quantitative Analysis For Improving Harvest Productivity For Biomass Crops, Magen Elizabeth Shedden

Masters Theses

Harvest cost is a major concern for making biomass a viable option. Unproductive time in-field significantly contributes to this cost. Variability of harvest timeliness is largely due to maneuvering equipment in-field, operator experience, equipment failures, and field and crop conditions, among other reasons. These are particularly important for farm management to know how to best handle interruptions during harvest. Consequently, there is a serious need to better account for harvest untimeliness. For this research, the crops of interest are Miscanthus and shrub willow. These crops are attractive for several reasons. They do not compete with cash crops because they grow …

An Economic Evaluation Of A Biofuel Supply Chain Utilizing Multiple Feedstocks, Huaqi Zhang

Masters Theses

Biomass is considered as one potential feedstock for biofuel production. However, the high cost of biomass-to-biofuel supply chain, attributed to biomass’s low bulk density and resulting harvest, storage, and transportation challenges, has been a major hindrance to the success of biomass-based biofuel industry. In addition, the issue of dry matter losses during storage for a feedstock has affected biomass quantity and quality if the feedstock is stored for several months after a single harvest in a year. One potential way to improve the economics of biomass supply chain is to reduce storage need and enhance the utilization of harvest equipment …

Diallel Analysis Of Biomass And Ethanol Yield In Leaves Versus Stems Of Lowland Switchgrass, Alexandria Christina Desantis

Masters Theses

Switchgrass (Panicum virgatum L.) is a warm season perennial grass used widely as a forage crop. This research seeks to address improving biomass yield and predicted ethanol yield through certain traits by the following objectives: (1) differences in average biomass and predicted ethanol yields from leaves versus stems, (2) genetic variance and heritability estimates of biomass and ethanol yield traits (3) general (GCA) and specific combining ability (SCA) among the five parents for biomass and ethanol yield, and (4) correlations between agronomic and morphological traits. Five parents with varying morphological traits were crossed in a diallel design, excluding selfs. …

Exploring The Potential To Penetrate The Energy Market For Tennessee-Produced Switchgrass, Fnu Shikha

Masters Theses

The need for alternative sources of energy which are renewable and environmentally friendly has focused attention on the development of biomass-based energy sector. Lignocellulosic energy crops such as switchgrass are considered potential feedstock for biomass-based energy because of wide range adaptability in conjunction with lower input requirements. However, the costs of the collection, storage, and transportation of the low density feedstock from farm to conversion facilities in the switchgrass supply chain pose a major barrier to the development of bioenergy sector.

The objective of the present study is to determine the optimal logistics configuration for Tennessee-produced switchgrass to penetrate the …

Genetic Variability For Biomass Yield, Yield Components, And Ethanol Yield Among Half-Sibs Of Switchgrass, Eifion Wyn Hughes

Masters Theses

For bioenergy crops to be an economical alternative to fossil fuels, rapid biological and technological advancements will need to occur. Some advancements can be accomplished by producing new switchgrass (Panicum virgatum L.) varieties with higher biomass and ethanol yields. The objective of this research was to quantify biomass and ethanol yield potential of four F₁ [F1] half-sib populations for future variety development as a bioenergy crop.

The four parental lines were PI 421999 (AR), PI 607837 (TX), PI 421552 (Cimarron), and Exp. # NSL-2001-1 (OK). Seed for one hundred and forty F₁ [F1] half-sib progeny were produced …

Forage And Biomass Dual-Purpose Harvest System Using Native Warm-Season Grasses, David Weston Mcintosh

Masters Theses

There has been increasing interest in utilizing native warm-season grasses (NWSGs), especially switchgrass, as a biomass feedstock for cellulosic ethanol production. Millions of hectares of crop and pasture in the mid-South are forecast to potentially be planted with switchgrass for biomass feedstock production. This could have a substantial impact on the region’s cattle industry, reducing forage production hectares. This study was conducted to determine the effect of early season harvest timing on forage and biomass of NWSGs designed for use in cellulosic ethanol production. The over-all hypothesis was to determine if an early forage harvest can be included in a …

Drought Response Of Populus Transformed With Stress Response Transcription Factors, Alina S. Campbell

Masters Theses

The economic feasibility of producing biomass-based fuels requires high-yielding feedstocks to supply biomass to biorefineries. Populus trees are a potential biomass feedstock due to their high yield, but their high water requirement limits productivity under drought conditions.

The number of genes controlling drought tolerance, and the long generation time for perennial species, slows cultivar development. Accelerated domestication proposes using the sequenced Populus genome to quickly incorporate target traits into productive clones by transgenesis.

Six putative drought tolerance transcription factors: DREB2A, DREB2B, AtMYB, AREB1/ABF2, MYB, and NAC, had been previously identified and manipulated in eastern cottonwood (Populus deltoides). Three …

The Study Of Plant Cell Walls Deconstruction Using Electron Beams Irradiation, Jetana Kittisenee

Masters Theses

Plant cell walls compose the largest source of sugars on earth and are a potential source after conversion for liquid transportation fuels. However, the crystalline region of cellulose and the lignin that incases it present significant obstacles for enzymes to digest. This lowers the sugar yield, which ultimately decreases the production efficiency of bioethanol. A pretreatment that could help lowering the amount of crystallinity; meanwhile, breakdown the matrix of lignin and polysaccharides that cover cellulose fibers would be ideal. Here we propose a physical pretreatment strategy of electron beam irradiation that could potentially decrease cellulose crystallinity as well as unzip …