Theses and Dissertations at Montana State University (MSU)
Permanent URI for this communityhttps://scholarworks.montana.edu/handle/1/732
Browse
6 results
Search Results
Item Instrumental design requirements for measurements of electrochemical reduction rates of haloorganics(Montana State University - Bozeman, College of Letters & Science, 1995) Hughes, Richard AllenItem Adult awareness of environmental degradation caused by technology : a component of Technological, Environmental and Agricultural Literacy (TEAL)(Montana State University - Bozeman, College of Education, Health & Human Development, 1997) Hester, Gregory AlanItem Invasiveness of Yellow Toadflax (Linaria Vulgaris) resulting from disturbance and environmental conditions(Montana State University - Bozeman, College of Agriculture, 2008) Lehnhoff, Erik Adam; Chairperson, Graduate Committee: Lisa J. Rew; Bruce D. Maxwell (co-chair)Invasive plant species are considered to be one of the greatest threats to ecosystems and biological diversity throughout the world, and are thus often aggressively managed. The degree of plant invasiveness, however, varies both with environment and with type of landscape disturbance. This research was designed to understand how the factors of environment and disturbance affect the invasiveness of Linaria vulgaris (yellow toadflax) in southwest Montana and to quantify the varying degrees of invasiveness resulting from each factor. Data were obtained through four separate projects. The effects of disturbance size and propagule pressure on L. vulgaris establishment were evaluated through a series of experiments in both disturbed and undisturbed plots. L. vulgaris establishment and survival were low in all plots, but followed the general trend of more successful establishment in larger disturbed plots and in disturbed plots with a higher seeding density. An invasiveness index was developed that quantified invasiveness between -4 and +4 based on changes in population density and plant occupancy within permanent monitoring grids. This index was applied to L. vulgaris populations in three distinct environments, and invasiveness was found to range from -1.9 (declining population) to 1.8 (invasive population), indicating that invasiveness varied widely based on environment. The effects of the disturbances of herbicide, digging, burning and vegetation clipping on established L. vulgaris populations were evaluated in four environments. In the first year after treatment, herbicide reduced invasiveness of L. vulgaris in all environments, while digging and burning increased invasiveness and clipping had no effect. In the second year, herbicide resulted in increased L. vulgaris invasiveness at the three sites dominated by forbs, while it still reduced invasiveness at the grass-dominated site. The other treatments had minimal effects. Finally, effects of the above disturbances on the whole plant community were assessed using relative species abundance, richness and diversity metrics. Treatments generally decreased these metrics initially, but values recovered over time, with the exception of the herbicide treatment. The results demonstrated that L. vulgaris population invasiveness and treatment effectiveness varies with environment, suggesting that prioritizing management on an environment basis may be appropriate.Item Changing soil degradation trends in Senegal with carbon sequestration payments(Montana State University - Bozeman, College of Agriculture, 2005) Gray, Kara Michelle; Chairperson, Graduate Committee: John Antle.In Sudo-Sahelian Africa, erosion and nutrient mining are prominent causes of soil degradation. In Senegal, harvesting grains and crop residue from the land impact heavily on soil carbon content, while the insufficient replacement of soil nutrients with fertilizers contributes to negative nutrient balances. Given the economic perspective of the rational farmer and the dynamic nature of crop and soil management issues, this thesis used a regional case study in the Groundnut Basin of Senegal to do the following: describe and assess economic incentives specific the to the case study region; model the farmer's production and decision making process; design carbon contract policies and model them within the farmer's decision making process; simulate the interaction between the current agricultural marketplace and potential carbon policies; and to assess the role that carbon sequestration could play in helping the region deal with soil degradation problems, if and when international action is taken to reduce greenhouse gas emissions.Item Nitrous oxide emissions from a Northern Great Plains soil as influenced by nitrogen fertilization and cropping systems(Montana State University - Bozeman, College of Agriculture, 2006) Dusenbury, Matthew Paul; Chairperson, Graduate Committee: Richard E. Engel.Agriculture has been identified by the Intergovernmental Panel on Climate Change (IPCC) as the major anthropogenic source of N₂O emissions. Field measurements of N₂O emissions are limited for cropping systems in the semi-arid Northern Great Plains (NGP). The study objectives were to determine temporal N₂O emission patterns for NGP cropping systems, and estimate fertilizer N induced emissions (FIE) and contrast with IPCC default methodology. No-till (NT) wheat (Triticum Aestivum L.)-fallow, wheat-wheat, and wheat-pea (Pisum sativum L.), and a conventional till (CT) wheat-fallow all with three N regimes (200 and 100 kg N ha-1 available N, unfertilized N control); plus a perennial grass system (CRP) were sampled over two years (15 Apr 2004 - 14 Apr 2006) using static chambers. Nitrous oxide emissions over two years were 209 to 1310 g N ha-1 for the cropping systems. Greatest N₂O emission activity occurred following urea-N fertilization (10-wk) and freeze-thaw cycles. The sum for these periods comprised 73-84% of total emissions. Emissions were positively correlated with urea-N fertilization rates and increased rapidly when water-filled pore was > 50%.Item Controlled degradation(Montana State University - Bozeman, College of Arts & Architecture, 2010) Spain, Brock Colter; Chairperson, Graduate Committee: Steven JuroszekOn November 20, 1943 young Higgins landing craft operator Leon Cooper ferried U.S. Marines of the Second Division ashore on the island of Betio, Tarawa Atoll. The Tarawa landing was to be the first American amphibious assault in World War II and at Red Beach it challenged an entrenched force of 5,000 Japanese soldiers. The fighting lasted only seventy-six hours but it remains one of the bloodiest offenses during WWII. Nearly 1,700 Americans died and over 2,000 wounded during the battle at Tarawa. Most of the dead, both American and Japanese alike, were quickly buried in unmarked graves and cemeteries on the island. Since WWII, some American remains have been recovered, accounted for, and returned to the United States. However, the remains of 564 U.S. Marines and countless Japanese soldiers have yet to come home. Several years later... Leon Cooper had returned home and made a life as a computer company executive. Since retiring, the 89 year old Malibu veteran has stumbled upon a new fight in a familiar place. A few years ago he learned of a landfill covering the bodies of his fallen comrades at Red Beach. Outraged he began spending his own money and raising awareness about the build-up of garbage and debris on hallowed ground. His efforts have resulted in nationwide recognition and a documentary, Return to Tarawa: The Leon Cooper Story. However, the ultimate goal has yet to be realized. Leon has made it his last work to clean-up Red Beach. Apart from local and regional governments not cooperating, rising sea levels have also posed a threat to Leon's efforts. With an intending doom dictating the timeline, the clean-up of Red Beach pales in comparison to the relocation of 10,000 natives from their homes in one of the poorest regions on earth. If not addressed the issues at Red Beach will simply be underwater. The moral line made at this juncture divides right from wrong and outlines actions in each. Are mounds of trash atop soldier's remains simply 'out of sight and out of mind'? Or is their trash in our oceans atop forgotten hero's buried at sea? History tells a story of man's inhumanity to man; a tale of war that led men to kill other men for shared principals and the translation of that naivety into a nation dumping trash on a graveyard. It is the goal of this thesis to explore the qualities of humankind that are embodied in a soldiers sacrifice by creating an architecture that controls degrading conditions in spite of certain destruction. This, a municipal waste management facility, chooses to hold the sacrifices of soldiers above their deaths and carries their bodies from the trash into a memoriam that eases trauma into memory while instituting new possibilities, new activities, and new images for a hopeful future.