Life Sciences Commons^™

Beech Bark Disease Distribution And Resistance In Michigan And Fungal Endophyte Ecology Of Resistant And Susceptible Beech (Fagus Grandifolia Ehrh.), Rachel E. Griesmer-Zakhar

Dissertations, Master's Theses and Master's Reports - Open

Beech bark disease (BBD), a non-native association of the fungal pathogen Neonectria faginata and the beech scale insect Cryptococcus fagisuga, has dramatically affected American beech within North American forests. To monitor the spread and effects of BBD in Michigan, a network of forest health monitoring plots was established in 2001 following the disease discovery in Ludington State Park (Mason County). Forest health canopy condition and basic forestry measurements including basal area were reassessed on beech trees in these plots in 2011 and 2012. The influence of bark-inhabiting fungal endophytes on BBD resistance was investigated by collecting cambium tissue from …

Verifying Success Of Artificial Reefs In The Huron-Erie Corridor For Lake Sturgeon, Emily K. Bouckaert

Dissertations, Master's Theses and Master's Reports - Open

Lake sturgeon (Acipenser fulvescens) were historically abundant in the Huron-Erie Corridor (HEC), a 160 km river/channel network composed of the St. Clair River, Lake St. Clair, and the Detroit River that connects Lake Huron to Lake Erie. In the HEC, most natural lake sturgeon spawning substrates have been eliminated or degraded as a result of channelization and dredging. To address significant habitat loss in HEC, multi-agency restoration efforts are underway to restore spawning substrate by constructing artificial spawning reefs. The main objective of this study was to conduct post-construction monitoring of lake sturgeon egg deposition and larval emergence near two …

The Role Of Ectomycorrhizal Fungi On Fertilized And Unfertilized Nursery Grown White Spruce, Alistair James Henry Smith Ii

Dissertations, Master's Theses and Master's Reports - Open

Nursery grown seedlings are an essential part of the forestry industry. These seedlings are grown under high nutrient conditions caused by fertilization. Though grown in a controlled environment, symbionts such as ectomycorrhizal fungi (EcMF) are often found in these conditions. To examine the effects of EcMF in these conditions, colonized Picea glauca seedlings were collected from Toumey Nursery in Watersmeet, MI. After collection, the EcMF present were morphotyped, and seedlings with different morphotypes were divided equally into two treatment types- fertilized and unfertilized. Seedlings received treatment for one growing season. After that time, seedlings were collected, ectomycorrhizas identified using morphotyping …

Effects Of Ethylene On Secondary Xylem Formation In Arabidopsis Thaliana, Haley M. Rupp

Dissertations, Master's Theses and Master's Reports - Open

Ethylene has myriad roles as a plant hormone, ranging from senescence and defending against pathogen attacks to fruit ripening and interactions with other hormones. It has been shown to increase cambial activity in poplar, but the effect on wood formation in Arabidopsis hypocotyl has not previously been studied. The Auxin-Regulated Gene involved in Organ Size (ARGOS), which increases organ size by lengthening the time for cell division, was found to be upregulated by ethylene. We tested the effect of ethylene treatment at 10 and 100 µM ACC on three genotypes of Arabidopsis, Col0 (wild-type), an ARGOS deficient mutant (argos), and …

Biochemical And Cellular Mechanisms Of Retina And Retinal Pigment Epithelium Apoptosis, Srinivasa Rao Sripathi

Dissertations, Master's Theses and Master's Reports - Open

Oxidative stress, intense light exposure and oxygen imbalances such as hypoxic or hyperoxic conditions perturb mitochondria, nuclear function and further lead to cellular damage of retina and retinal pigment epithelial (RPE) cells. Our major aim is to understand the various biochemical and proteomic events that occur during the progression of retina and RPE cell death. The comprehensive objectives of this dissertation are to understand the functional aspects of protein expression, posttranslational modifications, protein or lipid binding changes, phenotypic, morphological alterations and their regulation during the retina and RPE apoptosis under oxidative stress. The entire study is divided into four chapters …

Assessment Of Aspen And Northern Hardwoods Extent In Thirty Three Counties Of Upper/Lower Michigan, Sara Alian

Dissertations, Master's Theses and Master's Reports - Open

The importance of the United States' wood and wood byproducts as biomass feedstocks is increasing as the concern about security and sustainability of global energy production continues to rise. Thus, second generation woody feedstock sources in Michigan, e.g., hybrid poplar and hybrid willow (Populus spp.), are viewed as a potential source of biomass for the proposed biofuel ethanol production plant in Kinross, MI. It is important to gain an understanding of the spatial distribution of current feedstock sources, harvesting accessibility via the transportation infrastructure and land ownerships in order to ensure long-term feedstock extent. This research provides insights …

Factors Affecting Diporeia Growth Rates In Lake Superior, Miles J. Corcoran

Dissertations, Master's Theses and Master's Reports - Open

An ability to predict population dynamics of the amphipod Diporeia is important in understanding how energy pathways in the Lake Superior food web might be altered by disturbances to the ecosystem. Estimating growth rates for this prominent prey item for fish requires information on the physiological effects of changes to its environment. These effects have been investigated for Diporeia in other Great Lakes, but little is known about Lake Superior populations. The primary objective of this study is to obtain quantitative data for rates of Diporeia respiration and consumption that can be incorporated into a bioenergetics model for Lake Superior. …

Influence Of Vegetation Removal And Altering Water Levels On Co2 Flux Rates Of A Northern Bog, Laura M. Matkala

Dissertations, Master's Theses and Master's Reports - Open

Boreal peatlands contain approximately one third of the global soil carbon and are considered net sinks of atmospheric CO2. Water level position is one of the main regulators of CO2 fluxes in northern peatlands because it controls both the thickness of the aerobic layer in peat and plant communities. However, little is known about the role of different plant functional groups and their possible interaction with changing water level in boreal peatlands with regard to CO2 cycling. Climate change may also accelerate changes in hydrological conditions, changing both aerobic conditions and plant communities. To help answer these questions, this study …

Biomass Fuel-Briquettes And Improved Stoves In Dinsho, Ethiopia, Brian W. Barbre

Dissertations, Master's Theses and Master's Reports - Open

This report is a study of the development and implementation of a biomass fuel briquette and improved stove project in the highlands of Ethiopia. The primary goal of the project was to determine if the introduction of an improved stove would affect the acceptability of fuel briquettes. The secondary goal was to establish briquette and improved stove manufacturing associations in Dinsho and Rira towns. Two problems encountered during the project were cultural differences in material valuation, and difficulty working with local administrative frameworks and multi-organization communication difficulties. Both briquettes and improved stoves received positive feedback from respondents. Survey data indicated …

The Effects Of Black Locust (Robinia Pseudoacacia L.) On Understory Vegetation And Soils In A Northern Hardwood Forest, Keri A. Deneau

Dissertations, Master's Theses and Master's Reports - Open

No abstract provided.

Carbon In The Peatlands In The Great Lakes Region, Cassandra A. Ott

Dissertations, Master's Theses and Master's Reports - Open

Peatlands cover only ~3% of the global land area, but store ~30% of the worlds' soil carbon. There are many different peat types that store different amounts of carbon. Most inventories of carbon storage in northern peatlands have been conducted in the expansive Sphagnum dominated peatlands. Although, northern white cedar peatlands (NW cedar, Thuja occidentalis L.) are also one of the most common peatland types in the Great Lakes Region, occupying more than 2 million hectares. NW cedar swamps are understudied, due in part to the difficulties in collection methods. General lack of rapid and consistent sampling methods has also …

Plant-Mediated Effects On Microbial Diversity In Mesocosms Of An Oligotrophic Bog, Karl J. Romanowicz Iv

Dissertations, Master's Theses and Master's Reports - Open

Globally, peatlands occupy a small portion of terrestrial land area but contain up to one-third of all soil organic carbon. This carbon pool is vulnerable to increased decomposition under projected climate change scenarios but little is known about how plant functional groups will influence microbial communities responsible for regulating carbon cycling processes. Here we examined initial shifts in microbial community structure within two sampling depths under plant functional group manipulations in mesocosms of an oligotrophic bog. Microbial community composition for bacteria and archaea was characterized using targeted 16S rRNA Illumina gene sequencing. We found statistically distinct spatial patterns between the …

Spatial And Temporal Patterns In Ungulate-Ecosystem Interactions, Bryan D. Murray

Dissertations, Master's Theses and Master's Reports - Open

Ungulates are important components of a variety of ecosystems worldwide. This dissertation integrates aspects of ungulate and forest ecology to increase our understanding of how they work together in ways that are of interest to natural resource managers, educators, and those who are simply curious about nature. Although animal ecology and ecosystem ecology are often studied separately, one of the general goals of this dissertation is to examine how they interact across spatial and temporal scales. Forest ecosystems are heterogeneous across a range of scales. Spatial and temporal habitat use patterns of forest ungulates tend to be congregated in patches …

Local Use And Management Of Tasba (Senna Obtusifolia) In The Traditional Food System Of Sanguere Paul, North Cameroon, Mary E. Snyder

Dissertations, Master's Theses and Master's Reports - Open

The purpose of this study is to examine the importance of the wild edible weed tasba (Senna obtusifolia) in Sanguéré Paul, Cameroon by examining how households use and manage the plant. This study found that local management of tasba is minimal compared to other traditional vegetables. Tasba was collected most frequently from en brousse or the communal, fallowed land which is often too degraded for traditional field crops to grow. Women subsistence farmers were closely involved with tasba as they are the ones responsible for food production within the family. Socioeconomic differences between women affects how they manage tasba and …

Interactive Controls Of Water Table Position And Plant Functional Types On Peat Porewater Character In Northern Bog Ecosystems: Implications For Carbon Cycling Dynamics, Aleta L. Daniels

Dissertations, Master's Theses and Master's Reports - Open

Northern wetlands, and particularly peatlands, have been shown to store around 30% of the world's soil carbon and thus play a significant role in the carbon cycle of our planet. Changes in climate are altering peatland hydrology and vegetation communities. These changes are possibly resulting in declines in the ability of peatlands to sequester carbon because losses through carbon oxidation and mineralization are likely to increase relative to C inputs from net primary production in a warmer, drier climate. However, the consequences of interactive effects of altered hydrology and vegetation on carbon storage are not well understood. This research evaluated …

Application Of Remote Sensing In Aquatic Ecosystems, Foad Yousef

Dissertations, Master's Theses and Master's Reports - Open

I utilized state the art remote sensing and GIS (Geographical Information System) techniques to study large scale biological, physical and ecological processes of coastal, nearshore, and offshore waters of Lake Michigan and Lake Superior. These processes ranged from chlorophyll a and primary production time series analysies in Lake Michigan to coastal stamp sand threats on Buffalo Reef in Lake Superior. I used SeaWiFS (Sea-viewing Wide Field-of-view Sensor) satellite imagery to trace various biological, chemical and optical water properties of Lake Michigan during the past decade and to investigate the collapse of early spring primary production. Using spatial analysis techniques, I …

Evaluation Of Sugar Maple Dieback In The Upper Great Lakes Region And Development Of A Forest Health Youth Education Program, Tara L. Bal

Dissertations, Master's Theses and Master's Reports - Open

Acer saccharum Marsh., is one of the most valuable trees in the northern hardwood forests. Severe dieback was recently reported by area foresters in the western Upper Great Lakes Region. Sugar Maple has had a history of dieback over the last 100 years throughout its range and different variables have been identified as being the predisposing and inciting factors in different regions at different times. Some of the most common factors attributed to previous maple dieback episodes were insect defoliation outbreaks, inadequate precipitation, poor soils, atmospheric deposition, fungal pathogens, poor management, or a combination of these. The current sugar maple …

Computational Prediction Of The Sporulation Network In Clostridium Thermocellum, Changyi Jiang

Dissertations, Master's Theses and Master's Reports - Open

Sporulation is a process in which some bacteria divide asymmetrically to form tough protective endospores, which help them to survive in a hazardous environment for a quite long time. The factors which can trigger this process are diverse. Heat, radiation, chemicals and lacking of nutrition can all lead to the formation of endospores. This phenomenon will lead to low productivity during industrial production. However, the sporulation mechanism in a spore-forming bacterium, Clostridium theromcellum, is still unclear. Therefore, if a regulation network of sporulation can be built, we may figure out ways to inhibit this process. In this study, a …

Oligodeoxynucleotide Synthesis Using Protecting Groups And A Linker Cleavable Under Non-Nucleophilic Conditions, Xi Lin

Dissertations, Master's Theses and Master's Reports - Open

Oligodeoxynucleotides (ODNs) containing latent electrophilic groups can be highly useful in antisense drug development and many other applications such as chemical biology and medicine, where covalent cross-linking of ODNs with mRNA, protein and ODN is required. However, such ODN analogues cannot be synthesized using traditional technologies due to the strongly nucleophilic conditions used in traditional deprotection/cleavage process.

To solve this long lasting and highly challenging problem in nucleic acid chemistry, I used the 1,3-dithian-2-yl-methoxycarbonyl (Dmoc) function to protect the exo-amino groups on the nucleobases dA, dC and dG, and to design the linker between the nascent ODN and solid support. …

Evaluating Karner Blue Butterfly (Lycaeides Melissa Samuelis Nabokov) Habitat Selection In The State Of Wisconsin, Usa, Anna Nahuel Hess

Dissertations, Master's Theses and Master's Reports - Open

The federally endangered Karner blue butterfly (Lycaeides melissa samuelis Nabokov) persists in rare oak/pine grassland communities spanning across the Great Lakes region, relying on host plant wild blue lupine (Lupinus perennis). Conservation efforts since 1992 have led to the development of several programs that restore and monitor habitat. This study aims to evaluate Karner blue habitat selection in the state of Wisconsin and develop high-resolution tools for use in conservation efforts. Spatial predictive models developed during this study accurately predicted potential habitat across state properties based on soils and canopy cover, and identified ~51-100% of Karner blue occurrences based on …

Evaluation And Monitoring Of Ash (Fraxinus Spp.) Tolerant To Long-Term Emerald Ash Borer (Agrilus Planipennis [Coleoptera: Buprestidae]) Exposure, Kathryn G. Hietala

Dissertations, Master's Theses and Master's Reports - Open

Invasive insects that successfully establish in introduced areas can significantly alter natural communities. These pests require specific establishment criteria (e.g. host suitability) that, when known, can help quantify potential damage to infested areas. Emerald ash borer (Agrilus planipennis [Coleoptera: Buprestidae]) is an invasive phloem-feeding pest which is responsible for the death of millions of ash trees (Fraxinus spp. L.). Over 200 surviving ash trees were previously identified in the Huron-Clinton Metroparks located in southeast Michigan. Trees were assessed over a four year period and a hierarchical cluster analysis was performed on dieback, vigor, and presence of signs and …

Dissection Of Stress Response Networks Regulating Multiple Stresses In Rice, Rafi Shaik

Dissertations, Master's Theses and Master's Reports - Open

Important food crops like rice are constantly exposed to various stresses that can have devastating effect on their survival and productivity. Being sessile, these highly evolved organisms have developed elaborate molecular machineries to sense a mixture of stress signals and elicit a precise response to minimize the damage. However, recent discoveries revealed that the interplay of these stress regulatory and signaling molecules is highly complex and remains largely unknown. In this work, we conducted large scale analysis of differential gene expression using advanced computational methods to dissect regulation of stress response which is at the heart of all molecular changes …