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An Analysis Of Technical Assistance Providers In Copanch'orti' Guatemala, Victoria Lebeaux Jan 2013

An Analysis Of Technical Assistance Providers In Copanch'orti' Guatemala, Victoria Lebeaux

Graduate Theses and Dissertations

Guatemala has the fourth highest rate of chronic under-nutrition for children under five in the world. One region particularly impacted is the Copanch'orti' area of eastern Guatemala where chronic under-nutrition affected 61% of the population in 2008. Although efforts to solve the malnutrition problem have been underway for several decades, there is a persistent need for greater and better coordination and integration of food security programming, within and across sectors (agriculture, education, environment, health, etc.), as well as across local, regional, and national platforms. In this dissertation I addressed the question of how the actions of development practitioners can ...


Techno-Economic Analysis And Life Cycle Assessment Of The Corn Stover Biomass Feedstock Supply Chain System For A Midwest-Based First-Generation Cellulosic Biorefinery, Ajay Shah Jan 2013

Techno-Economic Analysis And Life Cycle Assessment Of The Corn Stover Biomass Feedstock Supply Chain System For A Midwest-Based First-Generation Cellulosic Biorefinery, Ajay Shah

Graduate Theses and Dissertations

Corn stover is the primary feedstock choice for most of the first-generation cellulosic biorefineries in the Midwest, and their rated capacities are in between 76 and 114 million liters per year (MLPY) (i.e., 20 and 30 million gallons per year (MGPY)). For the uninterrupted operation of these plants, a year-round supply of corn stover needs to be secured, which will require a robust, efficient, cost-effective and environmentally-balanced feedstock supply chain. However, there is limited techno-economic and environmental know-how in this area. Thus, the main objective of this dissertation is to stochastically analyze the technoeconomics, life-cycle energy use, and greenhouse ...


White-Faced Capuchins (Cebus Capucinus) Of Cahuita National Park, Costa Rica: Human Foods And Human Interactions, Jennifer Christine Campbell Jan 2013

White-Faced Capuchins (Cebus Capucinus) Of Cahuita National Park, Costa Rica: Human Foods And Human Interactions, Jennifer Christine Campbell

Graduate Theses and Dissertations

Cahuita National Park is an ecotourist destination in southeast Costa Rica. A troop of white-faced capuchins (Cebus capucinus) living in the park was reported by park officials as being problematic due to their food-raiding behavior. In May-June 2012 and again in December 2012-January 2013 I collected behavioral information in the form of scan samples and human-monkey interactions to assess the frequency and severity of these interactions. Type of food consumed was also noted, as consumption of human foods has been shown to cause both demographic and behavioral changes in non-human primate populations. Anthropogenic food sources accounted for 18% for the ...


Net Effects Of Batrachochytrium Dendrobatidis (Bd) And Fungicides On Anurans Across Life Stages, Jenise Brown Jan 2013

Net Effects Of Batrachochytrium Dendrobatidis (Bd) And Fungicides On Anurans Across Life Stages, Jenise Brown

Graduate Theses and Dissertations

Amphibians are declining at alarming rates globally. Multiple factors contribute to these declines, including chemical contaminants and emergent diseases. In recent years, agrochemical use, especially fungicide applications, has increased considerably. Previous studies have demonstrated that these agrochemicals leave application sites and enter wetlands via runoff and have detrimental effects on non-target organisms. For example, exposure to contaminants can have multifarious effects on amphibians, such as reducing their ability to deal with a secondary stressor, such as disease.

A pathogen that is found concomitant with chemical contaminants in aquatic systems is Batrachochytrium dendrobatidis (Bd). Bd has decimated amphibian populations worldwide. Susceptibility ...


Assessment Of A Modified Double Agar Layer Method To Detect Bacteriophage For Assessing The Potential Of Wastewater Reuse In Rural Bolivia, Sakira N. Hadley Jan 2013

Assessment Of A Modified Double Agar Layer Method To Detect Bacteriophage For Assessing The Potential Of Wastewater Reuse In Rural Bolivia, Sakira N. Hadley

Graduate Theses and Dissertations

Water scarcity is a global concern that impacts many developing countries, forcing people to depend on unclean water sources for domestic, agricultural, and industrial needs. Wastewater is an alternative water source that contains nutrients needed for crop growth. Wastewater reuse for agriculture can cause public health problems because of human exposure to pathogens. Pathogen monitoring is essential to evaluate the compliance of wastewater with established World Health Organization (WHO) and U.S. Environmental Protection Agency (EPA) wastewater reuse guidelines. Indicator organisms are commonly used to detect pathogens in water and wastewater because they are quick and easy to measure, non-pathogenic ...


Relative Survival Of Gags Mycteroperca Microlepis Released Within A Recreational Hook-And-Line Fishery: Application Of The Cox Regression Model To Control For Heterogeneity In A Large-Scale Mark-Recapture Study, Beverly J. Sauls Jan 2013

Relative Survival Of Gags Mycteroperca Microlepis Released Within A Recreational Hook-And-Line Fishery: Application Of The Cox Regression Model To Control For Heterogeneity In A Large-Scale Mark-Recapture Study, Beverly J. Sauls

Graduate Theses and Dissertations

The objectives of this study were to measure injuries and impairments directly observed from gags Mycteroperca microlepis caught and released within a large-scale recreational fishery, develop methods that may be used to rapidly assess the condition of reef fish discards, and estimate the total portion of discards in the fishery that suffer latent mortality. Fishery observers were placed on for-hire charter and headboat vessels operating in the Gulf of Mexico from June 2009 through December 2012 to directly observe reef fishes as they were caught by recreational anglers fishing with hook-and-line gear. Fish that were not retained by anglers were ...


The Influence Of Propagation Method And Stand Age On Miscanthus X Giganteus Performance In Iowa, Usa, Nicholas Boersma Jan 2013

The Influence Of Propagation Method And Stand Age On Miscanthus X Giganteus Performance In Iowa, Usa, Nicholas Boersma

Graduate Theses and Dissertations

Climate change and a desire for oil independency have stimulated interest in dedicated biomass crops for domestic biofuels production. Miscanthus × giganteus Greef et Deu., an exceptionally productive crop in the Midwestern USA, exhibits many ideal biomass crop traits, notably sterility which decreases invasive potential. Although a labor intensive process, rhizome propagation is the most common method for vegetatively propagating M. × giganteus. Stem propagation, investigated here, alleviates many challenges associated with rhizome production. Utilizing 30 °C soil and the first five nodal stem segments increased M. × giganteus propagation rates 12 fold of reported rhizome multiplication rates. Stem propagated plants (SPs) were ...


Development And Optimization Of Algal Cultivation Systems, Martin Gross Jan 2013

Development And Optimization Of Algal Cultivation Systems, Martin Gross

Graduate Theses and Dissertations

This thesis describes research done on two novel algae cultivation systems. The first system was an attached algal growth system to facilitate biomass harvest with improved biomass yield. In the attached system, algal cells were grown on the surface of a material rotating between the nutrient-rich liquid phase and the carbon dioxide-rich gaseous phase. The algal cells from the attached growth system were harvested by simply scraping off the algal biofilm. The operation conditions of the attached growth system were optimized to improve biomass productivity. A harvesting frequency of 7 days with a rotational speed of 4 rpm resulted in ...


Biophysical Interactions In Prairie Pothole Wetlands Of Iowa: Consequences For Macroinvertebrate Assemblages And Ecosystem Condition, Kristine Maurer Jan 2013

Biophysical Interactions In Prairie Pothole Wetlands Of Iowa: Consequences For Macroinvertebrate Assemblages And Ecosystem Condition, Kristine Maurer

Graduate Theses and Dissertations

Wetlands are capable of supporting diverse assemblages of plants and animals, and performing various ecosystem services (e.g., waterfowl production, flood mitigation). However, the capacity of a wetland to perform these functions is dependent upon its condition (i.e., ecosystem condition, integrity, or health). Wetland condition is affected and reflected by internal (within-system) biophysical features, and interactions among these features. To protect and effectively manage wetlands, it is essential that we identify reliable determinants and indicators of wetland condition. As a result of the inherent complexity of wetland ecosystem interactions, this knowledge is difficult to obtain. The objectives of this ...


Reproductive Decisions Of Mountain Plovers In Southern Phillips County, Montana, Paul Daniel Blom Skrade Jan 2013

Reproductive Decisions Of Mountain Plovers In Southern Phillips County, Montana, Paul Daniel Blom Skrade

Graduate Theses and Dissertations

The Mountain Plover (Charadrius montanus) is a shorebird of conservation concern that breeds in the Great Plains and the Great Basin. They have an uncommon uniparental care system where males and females tend separate nests. Although males and females have similar incubation and chick-rearing responsibilities, it is thought that the males arrive first to the breeding grounds in early to mid-April, establish loose territories, and compete for females. Long-term monitoring of this species in north-central Montana has allowed for studies comparing the effectiveness of the two sexes at separately raising young, showing evidence for differences in nest and brood survival ...


Hybrid Striped Bass: Culture And Use In Midwestern Waters, James Wamboldt Jan 2013

Hybrid Striped Bass: Culture And Use In Midwestern Waters, James Wamboldt

Graduate Theses and Dissertations

In response to increased demand from fisheries managers, the Iowa Department of Natural Resources and Iowa State University worked to produce standard operating procedures for pond culture of hybrid striped bass Morone saxatilis × M. chrysops in Iowa. In 2011 we evaluated an organic fertilization regime in nutrient rich earthen ponds. In addition to pond fertilization, the role of offering a supplemental commercial feed during phase I culture was also investigated within plastic-lined ponds. With greater utilization and stocking of hybrid striped bass fingerlings in local waters, we also sought to evaluate the effects that introductions have on the trophic dynamics ...


Development Of Best-Practices For Conserving Beneficial Insects Within Iowa's Agricultural Landscape, Kelly Ann Gill Jan 2013

Development Of Best-Practices For Conserving Beneficial Insects Within Iowa's Agricultural Landscape, Kelly Ann Gill

Graduate Theses and Dissertations

The annual value of crop pollination and biological control of plant pests provided by beneficial insects is estimated to be worth at least $22 billion to United States crop production. Beneficial insects that supply these services to agricultural lands are threatened by limited or suboptimal resources due to the loss of biodiversity in agroecosystems, which is a growing concern in agricultural states like Iowa. Conservation practices are recommended to address a multitude of conservation concerns related to Iowa's declining natural resources; however, guidelines for best practices that conserve beneficial insects are not well defined. Due to the valuable relationship ...


Effects Of Perennial And Cover Crops On Hydrology In Iowa, Ryan Goeken Jan 2013

Effects Of Perennial And Cover Crops On Hydrology In Iowa, Ryan Goeken

Graduate Theses and Dissertations

Since European settlement, and beginning in the 1940's, two dramatic shifts in land use have occurred in Iowa - the first from prairie and forest to tile-drained farmland, and the second from diverse rotations to a heavier concentration of corn-soybean rotations and continuous corn. These shifts in land use and management have altered hydrological and biogeochemical cycles in the Upper Midwest, but perennial and cover crops have the potential to assist in mediating changes in these cycles.

The first study in this thesis examines how the perennial forage (PF) crop orchardgrass (Dactylis glomerata) affects subsurface drainage as compared to a ...


Ecological Forestry To Enhance Stand Complexity: Songbird Community Response In A Red Pine (Pinus Resinosa) Forest, Eddie Lee Shea Jan 2013

Ecological Forestry To Enhance Stand Complexity: Songbird Community Response In A Red Pine (Pinus Resinosa) Forest, Eddie Lee Shea

Graduate Theses and Dissertations

Structural complexity has long been recognized as important for maintaining songbird diversity. In recognition of the simplified condition of many managed forests, forest scientists have initiated efforts aimed at increasing the structural and compositional complexity of forest stands. Songbird community assemblage following timber harvest has been studied to assess these enhancement efforts, though current literature is largely limited to short-term responses and may not reflect longer-term patterns in response. Through a designed, replicated (n = 4) experiment located in northern Minnesota, we evaluated bird community response to differences in forest structure created through retention harvesting over a ten-year period. Treatments include ...


The Influence Of Hydrologic And Riparian Factors On Stream Channel Stability In A Central Iowa Stream, Nicholas Slattery Leete Jan 2013

The Influence Of Hydrologic And Riparian Factors On Stream Channel Stability In A Central Iowa Stream, Nicholas Slattery Leete

Graduate Theses and Dissertations

Onion Creek, a 2nd order stream in central Iowa, is the focus of research on stream channel stability and sediment movement. A field survey of Onion Creek (Chapter 2) found 24.5% of the total streambank length was severely eroding and some reaches of the stream had up to 50% severely eroding streambanks. Hydrologic factors such as watershed size, stream channelization, and flow restrictions were more significant than riparian land use in explaining the incidence of severely eroding streambanks.

An analysis of channel movement on Onion Creek from 1939 to 2009 (Chapter 3) found significant local changes, with landowners straightening ...


Cultivating Local: Building A Local Food System In Western North Carolina, Allison S. Perrett Jan 2013

Cultivating Local: Building A Local Food System In Western North Carolina, Allison S. Perrett

Graduate Theses and Dissertations

This dissertation examines a movement in Western North Carolina to build a local food system, one grounded in the conditions and relationships of place. In 2000, Mountain Family Farms launched the Local Food Campaign to raise public awareness about the region's farms and farming heritage, to educate consumers about the benefits of buying food grown by local farms, and, ultimately, to build markets for locally grown food to sustain the region's farms. The campaign sparked a social movement and over a decade later local farms and locally grown food are a palpable feature of life in the mountains ...


Agricultural And Domestic Waste Contamination In Chilibre Panama And Potential Low-Cost Best Managament Practices, Christopher Etienne Weekes Jan 2013

Agricultural And Domestic Waste Contamination In Chilibre Panama And Potential Low-Cost Best Managament Practices, Christopher Etienne Weekes

Graduate Theses and Dissertations

Abstract

Sanitation coverage in the Republic of Panama is 5 to 10 percent below the Millennium Development Goals targets set for the country. Population growth, urbanization, unplanned development and waste mismanagement have resulted in improvised trash sites and waste discharges into river systems that are important components of the biologically diverse natural environment of Panama. The study sought to investigate and estimate the burden of waste from domestic and agricultural sources in three regions of the Chilibre corrigimiento (district). It was hypothesized that the water quality and land cover data would reflect that the most populated region in the study ...


Evaluating Habitat Vulnerability And Sustainability Of Urban Seagrass Resources To Sea Level Rise, Cynthia A. Meyer Jan 2013

Evaluating Habitat Vulnerability And Sustainability Of Urban Seagrass Resources To Sea Level Rise, Cynthia A. Meyer

Graduate Theses and Dissertations

The seagrass resource provides essential ecosystem functions for many marine species. This research evaluated the vulnerability and sustainability of the seagrass resource in an urbanized area to the effects of sea level rise. The assessment required analysis of information regarding the biogeography of the seagrass resource, and developing a method to model the spatial extent of the suitable habitat for seagrass, and applying the model to predict the implications of simulated sea level rise scenarios on the seagrass resource.

Examining the biogeography of the seagrass resource required the development of a seagrass monitoring and assessment field survey and a comprehensive ...