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Effects Of Management On Native And Exotic Plant Communities In Pictured Rocks National Lakeshore In The Upper Peninsula Of Michigan, Michelle Elise Latsch Jan 2011

Effects Of Management On Native And Exotic Plant Communities In Pictured Rocks National Lakeshore In The Upper Peninsula Of Michigan, Michelle Elise Latsch

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

Ecological disturbances may be caused by a range of biotic and abiotic factors. Among these are disturbances that result from human activities such as the introduction of exotic plants and land management activities. This dissertation addresses both of these types of disturbance in ecosystems in the Upper Peninsula of Michigan.

Invasive plants are a significant cause of disturbance at Pictured Rocks Natural Lakeshore. Management of invasive plants is dependent on understanding what areas are at risk of being invaded, what the consequences of an invasion are on native plant communities and how effective different tools are for managing the invasive …


An Ethnobotanical Survey Of The Economic And Cultural Significance Of Non-Timber Forest Products In The Southwest Rhodope Mountain Region Of Bulgaria, Callie A. Bertsch Jan 2011

An Ethnobotanical Survey Of The Economic And Cultural Significance Of Non-Timber Forest Products In The Southwest Rhodope Mountain Region Of Bulgaria, Callie A. Bertsch

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

The people of the southwestern Rhodope Mountains of Bulgaria live in small, mountainous villages and rural areas. They rely on berries, herbs, and mushrooms provided by the forest and maintain a lifestyle and culture of gathering them. This study determined the economic and landscape concentration of Non-Timber Forest Products (NTFPs) and how this has changed in the past twenty years in the region of Garmen. The objective was to gauge the cultural and economic significance of NTFPs in the lives of the people who live there. Data was collected using informal, open-ended interviews and through participant observation. Results indicate that …


Modeling And Classifying Variable Width Riparian Zones Utilizing Digital Elevation Models, Flood Height Data, Digital Soil Data And National Wetlands Inventory : A New Approach For Riparian Zone Delineation, Sinan A. Abood Jan 2011

Modeling And Classifying Variable Width Riparian Zones Utilizing Digital Elevation Models, Flood Height Data, Digital Soil Data And National Wetlands Inventory : A New Approach For Riparian Zone Delineation, Sinan A. Abood

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

Riparian zones are dynamic, transitional ecosystems between aquatic and terrestrial ecosystems with well defined vegetation and soil characteristics. Development of an all-encompassing definition for riparian ecotones, because of their high variability, is challenging. However, there are two primary factors that all riparian ecotones are dependent on: the watercourse and its associated floodplain. Previous approaches to riparian boundary delineation have utilized fixed width buffers, but this methodology has proven to be inadequate as it only takes the watercourse into consideration and ignores critical geomorphology, associated vegetation and soil characteristics. Our approach offers advantages over other previously used methods by utilizing: the …


Characterisation Of The Metacaspase Gene Family In Arabidopsis Thaliana, Paige N. Cox Jan 2011

Characterisation Of The Metacaspase Gene Family In Arabidopsis Thaliana, Paige N. Cox

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

Caspases are known to be involved in animal programmed cell death (PCD). The objective of this thesis was to use gene expression analysis and reverse genetics to determine if Arabidopsis metacaspase (AtMC) genes play a role in plant PCD. The majority of AtMC genes were found to be expressed nearly constitutively in various tissues, developmental stages, and under various inductive treatments. Transgenic Arabidopsis plants generated with AtMCpromoter::AtMCgene::GUS fusions showed expression of the reporter gene in leaves, vasculature, trichomes, siliques, anthers, and during embryo development. Preliminary phenotypic characterization of single and double Arabidopsis AtMC loss-of-function mutants suggested that the …


Warming Alters Photosynthetic Rates Of Sub-Boreal Peatland Vegetation, Arvo Aljaste Jan 2011

Warming Alters Photosynthetic Rates Of Sub-Boreal Peatland Vegetation, Arvo Aljaste

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

Boreal peatlands are important in the global carbon cycle. Despite covering only 3% of the global land area, peatlands store approximately one third of all soil carbon. Temperature is one of the major drivers in peatland carbon cycling as it affects both plant production and CO2 fluxes from soils. However, it is relatively unknown how boreal peatland plant photosynthesis is affected by higher temperatures. Therefore, we measured plant photosynthetic rates under two different warming treatments in a poor fen in Northern Michigan. Eighteen plots were established that were divided into three treatments: control, open-top chamber (OTC) warming and infrared …


Assessing Visual Disturbance Conditions On The Custer National Forest, Scott B. Robinson Jan 2011

Assessing Visual Disturbance Conditions On The Custer National Forest, Scott B. Robinson

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

Assessment of soil disturbance on the Custer National Forest was conducted during two summers to determine if the U.S. Forest Service Forest Soil Disturbance Monitoring Protocol (FSDMP) was able to distinguish post-harvest soil conditions in a chronological sequence of sites harvested using different ground-based logging systems. Results from the first year of sampling suggested that the FSDMP point sampling method may not be sensitive enough to measure post-harvest disturbance in stands with low levels of disturbance. Therefore, a revised random transect method was used during the second sampling season to determine the actual extent of soil disturbance in these cutting …


Open Top Chambers And Infrared Lamps : A Comparison Of Heating Efficacy And Co₂/Ch₄ Dynamics In A Lake Superior Coastal Peatland, Christopher P. Johnson Jan 2011

Open Top Chambers And Infrared Lamps : A Comparison Of Heating Efficacy And Co₂/Ch₄ Dynamics In A Lake Superior Coastal Peatland, Christopher P. Johnson

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

Experimental warming provides a method to determine how an ecosystem will respond to increased temperatures. Northern peatland ecosystems, sensitive to changing climates, provide an excellent setting for experimental warming. Storing great quantities of carbon, northern peatlands play a critical role in regulating global temperatures. Two of the most common methods of experimental warming include open top chambers (OTCs) and infrared (IR) lamps. These warming systems have been used in many ecosystems throughout the world, yet their efficacy to create a warmer environment is variable and has not been widely studied. To date, there has not been a direct, experimentally controlled …


Tracing The Source Of Groundwater For Three Different Coastal Peatlands Along Lake Superior, Margus Paesalu Jan 2011

Tracing The Source Of Groundwater For Three Different Coastal Peatlands Along Lake Superior, Margus Paesalu

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

The goal of this project was to investigate the influence of a large inland lake on adjacent coastal freshwater peatlands. The specific aim was to determine the source of groundwater for three differently formed peatlands located on the southern shore of Lake Superior. The groundwater study was conducted at Bete Grise, a peatland complex in a dune-swale system; Pequaming, a peatland developed in the swale of a tombolo; and Lightfoot Bay, a peatland developed in a barrier beach wetland complex.

To determine the source of groundwater in the peatlands, transects of six groundwater monitoring wells were established at each study …


The Spatial Distribution Of Copernicia Alba (Morong) In The District Of Bahia Negra, Paraguay, Michelle E. Cisz Jan 2011

The Spatial Distribution Of Copernicia Alba (Morong) In The District Of Bahia Negra, Paraguay, Michelle E. Cisz

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

The Humid Chaco of Northeast Paraguay harbors monoculture palm savannas in which Copernicia alba is the only dominant overstory species. The study’s objective was to provide the complete spatial distribution of a simple ecosystem lacking confounding factors of overstory competition and changes in slope. Palms within six, 50 x 50m plots were marked by their GPS location and measured for dbh and total stem height. The spatial distribution was individually analyzed for each plot at the local scale up to 12 m using Ripley’s K test. For the total population including juvenile and adult plants, the sample plots contained both …


Understanding Michigan Nonindustrial Private Forest Landowners Attitudes And Knowledge About Forest Management, Tõnis Tõnisson Jan 2011

Understanding Michigan Nonindustrial Private Forest Landowners Attitudes And Knowledge About Forest Management, Tõnis Tõnisson

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

Approximately one-fourth of the non-industrial private forestland (NIPF) owners in the state of Michigan, who collectively own approximately 50% of the private forested land, have conducted commercial timber harvest in recent years. Previous studies indicated that NIPFs preferred to manage their forest for a sustained yield of high-quality timber, but were limited to even-aged regeneration treatments or conversion for uneven-aged silviculture due to previous cuttings. Improved knowledge about NIPF’s intentions and forest management behavior could be useful for successful implementation of sustained yield management. This study’s objective was to identify more active NIPF’s attitudes towards timber management, their forest management …


The Effects Of Soil Moisture, Field-Scale Toposequential Position, And Slope On Yields In Irrigated Upland Rice Fields In Flores, Comayagua, Honduras, Kyle M. Earnshaw Jan 2011

The Effects Of Soil Moisture, Field-Scale Toposequential Position, And Slope On Yields In Irrigated Upland Rice Fields In Flores, Comayagua, Honduras, Kyle M. Earnshaw

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

Rice (Oryza sativa L.) is an important cash crop in Honduras because of the rice lobby’s size, willingness to protest, and ability to negotiate favorable price guarantees on a year-to-year basis. Despite the availability of inexpensive irrigation in the study area in Flores, La Villa de San Antonio, Comayagua, the rice farmers do not cultivate the crop using prescribed methods such as land leveling, puddling, and water conservation structures. Soil moisture (Volumetric Water Content) was measured using a soil moisture probe after the termination of the first irrigation within the tillering/vegetative, panicle emergence/flowering, post-flowering/pre-maturation and maturation stages. Yield data …


The Growth Response Of Planted Red Pine (Pinus Resinosa Ait.) To Alternative Thinning Regimes, Jolanta Agnieszka Len Jan 2011

The Growth Response Of Planted Red Pine (Pinus Resinosa Ait.) To Alternative Thinning Regimes, Jolanta Agnieszka Len

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

Red pine (Pinus resinosa Ait.) plantations have been established in Michigan with expectations of mixed final product goals: pulpwood, boltwood and possibly sawlogs. The effects of alternative treatments on tree and stand attributes were examined in: the Atlantic Mine trial, thinned in spring 2006 with three alternatives: (1) every fifth row removal plus crown thinning, (2) every third row removal plus crown thinning and (3) every third row removal plus thinning from below; the Crane Lake trial, thinned in fall 2004 with two alternatives: (1) every third row removal and (2) every third row removal plus thinning from above; …


Farmer Land Allocation For Maize, Groundnut And Cotton Production In Chipata District, Eastern Province, Zambia, Kristina M. Denison Jan 2011

Farmer Land Allocation For Maize, Groundnut And Cotton Production In Chipata District, Eastern Province, Zambia, Kristina M. Denison

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

Small-scale farmers in the Chipata District of Zambia rely on their farm fields to grow maize and groundnuts for food security. Cotton production and surplus food security crops are used to generate income to provide for their families. With increasing population pressure, available land has decreased and farmers struggle to provide the necessary food requirements and income to meet their family’s needs. The purpose of the study was to determine how a farmer can best allocate his land to produce maize, groundnuts and cotton when constrained by labor and capital resources to generate the highest potential for food security and …


The Effects Of A Changing Climate On Root Respiration Of Woody Plants In Sugar Maple Forests And Northern Peatlands, Mickey P. Jarvi Jan 2011

The Effects Of A Changing Climate On Root Respiration Of Woody Plants In Sugar Maple Forests And Northern Peatlands, Mickey P. Jarvi

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

Global climate change might significantly impact future ecosystems. The purpose of this thesis was to investigate potential changes in woody plant fine root respiration in response to a changing climate. In a sugar maple dominated northern hardwood forest, the soil was experimentally warmed (+4 °C) to determine if the tree roots could metabolically acclimate to warmer soil conditions. After one and a half years of soil warming, there was an indication of slight acclimation in the fine roots of sugar maple, helping the ecosystem avoid excessive C loss to the atmosphere. In a poor fen northern peatland in northern Michigan, …


Variation In Carbon Content Of Tropical Tree Species From Ghana, Daniel Yeboah Jan 2011

Variation In Carbon Content Of Tropical Tree Species From Ghana, Daniel Yeboah

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

Most research on carbon content of trees has focused on temperate tree species with little information existing on the carbon content of tropical tree species. This study investigated the variation in carbon content of selected tropical tree species and compared carbon content of Khaya spp from two ecozones in Ghana. Allometric equations developed for mixed-plantation stands for wet evergreen forest verified the expected strong relationship between tree volumes and dbh (r2>0.93) and volume and dbh2×height (r2>0.97). Carbon concentration, wood density and carbon content differed significantly among species. Volume at age 12 ranged from 0.01 …


Planting And Production Of Switchgrass (Panicum Virgatum L.) As A Bioenergy Crop In Michigan's Upper Peninsula, Kassidy Nikole Yatso Jan 2011

Planting And Production Of Switchgrass (Panicum Virgatum L.) As A Bioenergy Crop In Michigan's Upper Peninsula, Kassidy Nikole Yatso

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

Switchgrass (Panicum virgatum L.) is a perennial grass holding great promise as a biofuel resource. While Michigan’s Upper Peninsula has an appropriate land base and climatic conditions, there is little research exploring the possibilities of switchgrass production. The overall objectives of this research were to investigate switchgrass establishment in the northern edge of its distribution through: investigating the effects of competition on the germination and establishment of switchgrass through the developmental and competitive characteristics of Cave-in-Rock switchgrass and large crabgrass (Digitaria sanguinalis L.) in Michigan’s Upper Peninsula; and, determining the optimum planting depths and timing for switchgrass in …


Estimation Of Scots Pine Defoliation By The Common Pine Sawfly (Diprion Pini L.) Using Multi-Temporal Radar Data, Petri T. Latva-Käyrä Jan 2011

Estimation Of Scots Pine Defoliation By The Common Pine Sawfly (Diprion Pini L.) Using Multi-Temporal Radar Data, Petri T. Latva-Käyrä

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

In 1998-2001 Finland suffered the most severe insect outbreak ever recorded, over 500,000 hectares. The outbreak was caused by the common pine sawfly (Diprion pini L.). The outbreak has continued in the study area, Palokangas, ever since. To find a good method to monitor this type of outbreaks, the purpose of this study was to examine the efficacy of multi-temporal ERS-2 and ENVISAT SAR imagery for estimating Scots pine (Pinus sylvestris L.) defoliation. Three methods were tested: unsupervised k-means clustering, supervised linear discriminant analysis (LDA) and logistic regression. In addition, I assessed if harvested areas could be differentiated …


Will Whole-Tree Harvest Of Jack Pine (Pinus Banksiana) Deplete Soil Nutrients In Low-Productivity Sand Soils?, Victoria L. Veach Jan 2011

Will Whole-Tree Harvest Of Jack Pine (Pinus Banksiana) Deplete Soil Nutrients In Low-Productivity Sand Soils?, Victoria L. Veach

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

In 2009 and 2010 a study was conducted on the Hiawatha National Forest (HNF) to determine if whole-tree harvest (WTH) of jack pine would deplete the soil nutrients in the very coarse-textured Rubicon soil. WTH is restricted on Rubicon sand in order to preserve the soil fertility, but the increasing construction of biomass-fueled power plants is expected to increase the demand for forest biomass. The specific objectives of this study were to estimate biomass and nutrient content of above- and below-ground tree components in mature jack pine (Pinus banksiana) stands growing on a coarse-textured, low-productivity soil, determine pools …


Impact Of Copper Mine Tailings (Stamp Sand) On Survival And Development Of Aquatic Organisms Near Gay, Michigan, Danielle M. Haak Jan 2011

Impact Of Copper Mine Tailings (Stamp Sand) On Survival And Development Of Aquatic Organisms Near Gay, Michigan, Danielle M. Haak

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

Heavy metal-rich copper mine tailings, called stamp sands, were dumped by mining companies directly into streams and along the Lake Superior shoreline, degrading Keweenaw Peninsula waterways. One of the largest disposal sites is near Gay, Michigan, where tailings have been moved along the shoreline by currents since mining ceased. As a result, the smallest sand particles have been washed into deeper water and are filling the interstitial spaces of Buffalo Reef, a critical lake trout spawning site. This research is the first to investigate if stamp sand is detrimental to survival and early development of eggs and larvae of lake …


Relationship Between Instream Habitat Characteristics, Emergent Insects, And Riparian Bird Communities, Kyle D. Forgette Jan 2011

Relationship Between Instream Habitat Characteristics, Emergent Insects, And Riparian Bird Communities, Kyle D. Forgette

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

Streams and riparian areas can be intricately connected via physical and biotic interactions that influence habitat conditions and supply resource subsidies between these ecosystems. Streambed characteristics such as the size of substrate particles influence the composition and the abundance of emergent aquatic insects, which can be an important resource for riparian breeding birds. We predict fine sediment abundance in small headwater streams directly affects the composition and number of emergent insects while it may indirectly affect riparian bird assemblages. Streams with abundant fine sediments that embed larger substrates should have lower emergence of large insects such as phemeroptera, Plecoptera and …


Effects Of Fixed Night Shift Work On 24 Hour Blood Pressure Regulation, State Anxiety Levels And Total Sleep Time, Jennifer L. Witting Jan 2011

Effects Of Fixed Night Shift Work On 24 Hour Blood Pressure Regulation, State Anxiety Levels And Total Sleep Time, Jennifer L. Witting

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

Nearly 22 million Americans operate as shift workers, and shift work has been linked to the development of cardiovascular disease (CVD). This study is aimed at identifying pivotal risk factors of CVD by assessing 24 hour ambulatory blood pressure, state anxiety levels and sleep patterns in 12 hour fixed shift workers. We hypothesized that night shift work would negatively affect blood pressure regulation, anxiety levels and sleep patterns. A total of 28 subjects (ages 22-60) were divided into two groups: 12 hour fixed night shift workers (n=15) and 12 hour fixed day shift workers (n=13). 24 hour ambulatory blood pressure …


Omega-3 Fatty Acids And The Neurovascular Responses To Mental Stress In Humans, Christopher Elmer Schwartz Jan 2011

Omega-3 Fatty Acids And The Neurovascular Responses To Mental Stress In Humans, Christopher Elmer Schwartz

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

Hypertension is the most prevalent form of cardiovascular disease (CVD) in the world, and is known to increase the risk for developing other diseases. Recently, the American Heart Association introduced a new classification of blood pressure, prehypertension (PHT). The criteria for PHT include a systolic of 120-139 mmHg and/or a diastolic blood pressure of 80-89 mmHg. It has been observed that individuals with PHT have a higher risk of developing hypertension later in life. Therefore, it is important to understand the mechanisms contributing to PHT in order to possibly prevent hypertension. Omega-3 fatty acids found in fish oils have been …


Comparing Remote Sensing And Ground-Based Methods Of Quantifying Cover Type And Carbon Storage In An Urban Forest, Christine L. Jones Jan 2011

Comparing Remote Sensing And Ground-Based Methods Of Quantifying Cover Type And Carbon Storage In An Urban Forest, Christine L. Jones

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

Understanding the canopy cover of an urban environment leads to better estimates of carbon storage and more informed management decisions by urban foresters. The most commonly used method for assessing urban forest cover type extent is ground surveys, which can be both timeconsuming and expensive. The analysis of aerial photos is an alternative method that is faster, cheaper, and can cover a larger number of sites, but may be less accurate. The objectives of this paper were (1) to compare three methods of cover type assessment for Los Angeles, CA: handdelineation of aerial photos in ArcMap, supervised classification of aerial …