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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
351

Urban Agriculture Stormwater Management in California Cities

Cohen, Rachel L 01 June 2013 (has links) (PDF)
Cities within California are beginning to incorporate urban agriculture into their land use designations. Prompted by residents and local organizations, cities are hoping to capture the benefits that urban agriculture provides. Research has shown that urban agriculture renews and beautifies neighborhoods, provides healthy food choices, increases public health, has the potential to help with stormwater runoff, creates jobs, and fosters community. In the last few years, several California cities have made headlines as they have adopted new zoning codes that include urban agriculture. In reviewing these new zoning codes and exploring the topic of urban agriculture, it became evident that just because an urban farm was small, organic and provided certain benefits that it was not free from impacting its surroundings. As more urban agricultural ventures are established within cities, planners have to carefully consider their effect. One such impact could be stormwater pollution. There is insufficient research to determine whether there is a relationship between urban agriculture and stormwater, however, studies on conventional agriculture and urban landscaping (mainly urban lawns) show that each of these areas pollute the local water bodies with sediment, chemicals, and nutrients. Is urban agriculture different? This thesis utilizes two case studies within California, the City of Oakland and the City of San Diego, to examine the similarities and differences between each city’s urban agriculture ordinances and evaluate whether or not the cities have adjusted stormwater requirements in parallel with these ordinances. Interview responses and site visits in each city were analyzed and compared to expound upon the approaches each city engaged. Using the collected data and analysis as a base, a set of guidelines was created for managing stormwater runoff from urban agriculture.
352

Ecological Consequences of Lost Anadromous Forage Fish in Freshwater Ecosystems

Mattocks, Steven R 07 November 2016 (has links)
Beginning in the early 1600s, dam construction in New England obstructed anadromous fish access to spawning grounds during migration. As a result, anadromous forage fish populations have declined, which has impacted freshwater, marine, and terrestrial ecosystems. To determine the impacts of dams on anadromous forage fish and freshwater ecosystems, I used historical and current data to estimate population changes in alewives (Alosa pseudoharengus) from 1600-1900. A significant reduction in spawning habitat occurred in New England as a result of 1,642 dams constructed between 1600 and 1900, resulting in 14.8% and 16.6% lake and stream habitat remaining by 1900, respectively. In eight New England watersheds, this translates to an estimated cumulative annual loss of 30 B juvenile alewives available as freshwater forage and 538 M year 1, 2 and 3 alewives available as marine forage. The cumulative annual lost number of adult return spawners was conservatively 17 M fish, or 3,642 metric tons. Lost marine-derived nutrients from adult return spawners were 11 T phosphorus, 64 T nitrogen, and 410 T carbon. A comparison of predator fish growth and condition in alewife and non-alewife lakes showed that white perch (Morone Americana) and yellow perch (Perca flavescens) have higher condition in early summer in lakes with alewives. Predator growth rates (length-at-age) were significantly higher in early life stages (ages 1 and 2) when alewives were present, but significantly lower in late life stages (ages 3 and older). Results indicate a greater maximum length obtained by mature fish when alewives are absent, and an earlier age and length at maturity when alewives are present. These results indicate significant ecosystem impacts of lost anadromous forage fish, with bottom-up trophic effects across multiple time scales and biological processes. An ecosystem-based management approach should be used by inland and marine aquatic managers, and ecosystem connectivity and trophic interactions should be considered when managing migratory fish and prioritizing restoration goals.
353

Climate Adaptation and Water Conservation Decision-Making in Paso Robles, California Vineyards

Klier, Christopher R 01 August 2021 (has links) (PDF)
This paper examines vineyard perceptions and adoption of climate change adaptation and water conservation measures in the Paso Robles American Viticultural Area (AVA). A survey was distributed to all 220 vineyards and vineyard management companies that operate in the AVA, with a 53.64% response rate. The objective of the survey was to determine vineyard manager and owner attitudes towards climate change and adaptation, as well as their perceptions of how these threats would impact their operation. A second objective was to document the current level of water conservation and climate adaptation while identifying the barriers and opportunities for further adoption of these practices. The third objective was to share a climate projection to assess perceived impacts, attitudes, and perceptions of the projection and capacity to adapt. The final objective was to develop a typology to assist targeted outreach of vineyards. Our results showed that the most important current climate impact is heat, with water regulations and supply being the biggest concern in the future. Vineyards were also found to be relatively unsure about their capability to further implement adaptation measures, with relatively low adoption of most practices already. Decision support tools, like the climate projection, were found to be useful and desired by vineyards for management. Results of our study showed that trust in the information source can be a barrier to use of these tools. We identified further barriers to adoption of practices and identified an outreach strategy using a typology of vineyards, which focused on smaller vineyards and those without wineries. These results can be used to increase efficacy of government and NGO programs that aim to support climate adaptation and water conservation in the region.
354

Adoption of sustainable forestry practices by Non-Industrial Private Forest owners in Virginia

Rasamoelina, Maminiaina Solonirina 01 July 2008 (has links)
The concept of Sustainable Forest Management (SFM) has been promoted in the past few decades all over the world. Non-industrial private forest (NIPF) owners play an important role in that aspect in the U.S. because of their number (about 16 millions), the size of forest land under their control (about half of all forest land in the continental US), and the dynamism of their population (increasing number of new owners). This study sought to better understand how NIPF owners come to a decision for adoption (or non-adoption) of SFM practices. We developed a theoretical model combining four theories (the Value-Belief-Norm theory, the Theory of Planned Behavior, the Elaboration Likelihood Model, and the Innovation-Diffusion Process) to explain NIPF's decision making. Using multivariate analyses, we determined which elements of the developed theoretical model were significant in explaining adoption of eight groups of practices. Overall, some of the most significant predictors of adoption we identified were technical assistance, motivations for owning land and the use of a written management plan. Particular attention was also directed toward the eventual relationship between education and adoption of SFM practices and it was found that NIPF owners who attended educational programs tended to be likely adopters compared to those who did not attend any educational program. Since SFM was not limited to the US, we also analyzed the concept of SFM with the same goals as in the US, but under a completely different context (socio-cultural, economic and ecologic) in Africa, through the community-based natural resource management (CBNRM) system. We used four case studies and focused on criteria such as participation, equity (both procedural and distributive, power devolution, trust, etc) to analyze how CBNRM works on the field, what lessons to take from the cases to better ensure the goal of sustainability of the resources. / Ph. D.
355

Evaluating soil health changes following cover crop and no-till integration into a soybean (Glycine max) cropping system in the Mississippi Alluvial Valley

Firth, Alexandra Gwin 13 May 2022 (has links)
The transition of natural landscapes to intensive agricultural uses has resulted in severe loss of soil organic carbon (SOC), increased CO₂ emissions, river depletion, and groundwater overdraft. Despite negative documented effects of agricultural land use (i.e., soil erosion, nutrient runoff) on critical natural resources (i.e., water, soil), food production must increase to meet the demands of a rising human population. Given the environmental and agricultural productivity concerns of intensely managed soils, it is critical to implement conservation practices that mitigate the negative effects of crop production and enhance environmental integrity. In the Mississippi Alluvial Valley (MAV) region of Mississippi, USA, the adoption of cover crop (CC) and no-tillage (NT) management practices has been low because of a lack of research specific to the regional nuances. Therefore, this study assessed the long-term soil physiochemical and biological responses from integrating CC and NT management to agricultural soils of the region. Research plots were established in a split-block design with two tillage treatments: NT and reduced tillage (RT) and three CC treatments: no cover (NC), rye (RY) and a rye+clover (RC) mix. Soil samples were taken during the growing season of 2019 and 2020. Bulk density was found to be significantly lower in NT plots and aggregate stability was greatest in plots with a single CC species. Moisture retention increased in NT.. Soil organic carbon was greater in NT and CC treatments and there was no difference in CO₂ flux. Bacterial abundance had a positive effect on SOC but a negative effect on CO₂. The rate of proportional change and pattern of variability in C pools suggested loss of SOC in reduced tillage (RT) treatments. Microbial abundance, functional genes and enzyme activity was greater in NT with CC, but diversity was greater in RT. No-tillage practices lower diversity and influence long-term community changes while CC practices enact a seasonal response to environmental conditions. I conclude that in heavy clay soils of the mid-South region of the MAV, RT with a CC is optimal for soil health traits associated with crop sustainability, however the management will still contribute to increased CO₂ emissions.
356

Capturing Critical Institutionalism: A Synthesis of Key Themes and Debates

Hall, Kurt V., Cleaver, Frances D., Franks, Tom R., Maganga, F. January 2014 (has links)
No / The article aims to provide a synthesis of key discussions within scholarship that is critical of Mainstream Institutionalism. It adopts a thematic approach to chart debate and areas of convergence about key issues. The first section of the article briefly charts the rise to prominence of the mainstream 'collective action' school. Each of the themes identified as central to the alternative critical approach is then examined in turn. These are the 'homogenous community' critique, the avoidance of politics critique (further divided into ideational politics and politics of local empowerment) and the sociological critique. The article concludes by reflecting on the challenge of 'making complexity legible' that faces the nascent critical tradition in institutional analysis.
357

A review of lessons learned to inform capacity-building for sustainable nature-based tourism development in the European Union funded ʺSupport to the Wild Coast Spatial Development Initiative Pilot Programmeʺ

Wright, Brian Bradley January 2006 (has links)
This case-study establishes the influences of power-knowledge relationships on capacity-building for sustainability in the European Union Funded ‘Wild Coast Spatial Development Initiative Pilot Programme’ (EU Programme). It aims to capture the lessons learned for capacitybuilding to support nature-based tourism initiatives on the Wild Coast. The EU Programme aimed to achieve economic and social development of previously disadvantaged communities through nature-based tourism enterprises, and to develop capacity of local authorities and communities to support environmental management. The study discusses common trends in thematic categories emerging from the research data, and contextualises research findings in a broader development landscape. This study indicates that power-knowledge relations were reflected in the EU Programme’s development ideology by an exclusionary development approach, which lacked a participatory ethos. This exclusionary approach did not support an enabling environment for capacity-building. This development approach, guiding the programme conceptualization, design and implementation processes, resulted in a programme with unrealistic objectives, time-frames and resource allocations; a programme resisted by provincial and local government. The study provides a causal link between participation, programme relevance, programme ownership, commitment of stakeholders, effective management and capacity-building for sustainable programme implementation. The study argues that the underlying motivation for the exclusionary EU development ideology in the programme is driven by a risk management strategy. This approach allows the EU to hold power in the development process, whereas, an inclusionary participative development methodology would require a more in-depth negotiation with stakeholders, thereby requiring the EU to relinquish existing levels of power and control. This may increase the risk of an unexpected programme design outcome and associated exposure to financial risk. It may also have a significant financial effect on donor countries' consultancies and consultants currently driving the development industry. This study recommends an interactive-participative methodology for programme design and implementation, if an enabling environment for capacity-building is to be created. In addition, all programme stakeholders must share contractual accountability for programme outcomes. This requires a paradigm shift in the EU development ideology to an inclusionary methodology. However, this research suggests that the current EU development approach will not voluntarily change. I, therefore, argue that South Africa needs to develop a legislative framework that will guide donor-funded development programme methodology, to support an enabling environment for capacity-building.
358

Gestion des ressources naturelles, dégradation de l’environnement et stratégies de subsistance dans le désert de Thar : étude ethnographique dans la région du Marwar, au Rajasthan en Inde

Gagné, Karine 08 1900 (has links)
Cette recherche porte sur les origines et les effets de la dégradation de l’environnement dans le désert de Thar, au Rajasthan en Inde. Elle expose les processus politico-économiques qui conditionnent la gestion des ressources naturelles dans la région du Marwar depuis l’indépendance de l’Inde à aujourd’hui. Les modes de gestion des ressources environnementales et agraires dans le contexte du système jagirdari, un système foncier domanial qui prévalait dans la région avant l’indépendance de l’Inde, sont d’abord présentés. S’en suit une analyse de la manière dont les diverses idéologies liées au développement postcolonial ont reconfiguré le paysage socio-administratif et environnemental de la région. Ces transformations ont engendré des désordres écologiques qui ont donné lieu à une crise environnementale et agraire qui connaît son paroxysme avec les nombreux déficits pluviométriques qui sévissent depuis la dernière décennie dans la région. À partir d’une recherche de terrain effectuée dans la communauté de Givas, l’impact – au plan physique et métaphysique – de ces problèmes environnementaux sur la population locale est examiné. L’étude porte également sur les réponses à ces changements, soit les stratégies de subsistance adoptées par la population locale, de même que les interventions déployées par une organisation non gouvernementale et par l’État indien – à travers le National Rural Employment Guarantee Act (NREGA). L’analyse démontre que l’expérience de la dégradation de l’environnement, à travers ses effets et les stratégies d’adaptation qui s’en suivent, est tributaire de facteurs politiques, économiques et socioculturels et donc différenciée selon le genre, la classe et la caste. / This research focuses on the origins and the consequences of environmental degradation in the Thar Desert in the State of Rajasthan, India. It outlines the political and economic processes that have influenced how natural resources are managed in the region of Marwar since Indian independence. First are presented the modes of agrarian and natural resources management that were current during the jagirdari, the pre-independence land tenure system that prevailed in this region. This is followed by an analysis of how different ideologies of postcolonial development have reshaped the social, administrative and environmental landscape of this region. These changes have led to ecological disruptions which have given rise to an environmental and agrarian crisis that has now reached a critical point with the rainfall deficits of the past decade in this region. Based on field research conducted in the community of Givas, the implications – physical and metaphysical – of these environmental problems are analyzed. The study also looks at the responses generated in order to cope with these changes, namely the livelihood strategies adopted by the local people, as well as the interventions from a non-government organization and the Indian state – through the National Rural Employment Guarantee Act (NREGA). The analysis reveals that the experience of environmental degradation, through its effects and responses, is conditioned by political, economic and sociocultural factors, and thus differentiated by gender, class and caste.
359

PROOF-OF-CONCEPT OF ENVIRONMENTAL DNA TOOLS FOR ATLANTIC STURGEON MANAGEMENT

Hinkle, Jameson 01 January 2015 (has links)
Abstract The Atlantic Sturgeon (Acipenser oxyrinchus oxyrinchus, Mitchell) is an anadromous species that spawns in tidal freshwater rivers from Canada to Florida. Overfishing, river sedimentation and alteration of the river bottom have decreased Atlantic Sturgeon populations, and NOAA lists the species as endangered. Ecologists sometimes find it difficult to locate individuals of a species that is rare, endangered or invasive. The need for methods less invasive that can create more resolution of cryptic species presence is necessary. Environmental DNA (eDNA) is a non-invasive means of detecting rare, endangered, or invasive species by isolating nuclear or mitochondrial DNA (mtDNA) from the water column. We evaluated the potential of eDNA to document the presence of Atlantic Sturgeon in the James River, Virginia. Genetic primers targeted the mitochondrial Cytochrome Oxydase I gene, and a restriction enzyme assay (DraIII) was developed. Positive control mesocosm and James River samples revealed a nonspecific sequence—mostly bacteria commonly seen in environmental waters. Methods more stringent to a single species was necessary. Novel qPCR primers were derived from a second region of Cytochrome Oxydase II, and subject to quantitative PCR. This technique correctly identified Atlantic Sturgeon DNA and differentiated among other fish taxa commonly occurring in the lower James River, Virginia. Quantitative PCR had a biomass detection limit of 32.3 ug/L and subsequent analysis of catchment of Atlantic Sturgeon from the Lower James River, Virginia from the fall of 2013 provided estimates of 264.2 ug/L Atlantic Sturgeon biomass. Quantitative PCR sensitivity analysis and incorporation of studies of the hydrology of the James River should be done to further define habitat utilization by local Atlantic Sturgeon populations. IACUC: AD20127
360

Spatiotemporal Analyses of Recycled Water Production

Archer, Jana E. 01 May 2017 (has links)
Increased demands on water supplies caused by population expansion, saltwater intrusion, and drought have led to water shortages which may be addressed by use of recycled water as recycled water products. Study I investigated recycled water production in Florida and California during 2009 to detect gaps in distribution and identify areas for expansion. Gaps were detected along the panhandle and Miami, Florida, as well as the northern and southwestern regions in California. Study II examined gaps in distribution, identified temporal change, and located areas for expansion for Florida in 2009 and 2015. Production increased in the northern and southern regions of Florida but decreased in Southwest Florida. Recycled water is an essential component water management a broader adoption of recycled water will increase water conservation in water-stressed coastal communities by allocating recycled water for purposes that once used potable freshwater.

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