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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.
231

Exploring the impact of end-user engagement on the diffusion and adoption of a climate resilience tool in the Gulf of Mexico

Collini, Renee C 13 May 2022 (has links)
Climate change-related hazards negatively impact ecosystems, economies, and quality of life. Significant resources have been invested in data collection and research with the goal of enhanced understanding and capacity to predict future conditions in order to mitigate or adapt to intensifying hazard risk. The expansive production of climate science has generated a necessary complimentary enterprise dedicated to enhancing decision-makers’ understanding of and access to climate science as it is essential for future societal and ecological well-being. Though the aim of these many tools is to support resilient decision-making in the face of climate change, professionals report an underutilization of climate resilience tools. It has been suggested that stakeholder engagement during climate resilience tool development will improve the rates of use; however, there have been no studies to explore if the findings from tool diffusion and adoption studies in other sectors translate to climate resilience tools. An end-user engagement process for the development of a climate resilience tool was established and implemented. The process itself and the outcomes of the process, in this case an online climate decision-support tool called Gulf TREE (www.GulfTREE.org), were studied. Findings included documenting that end-user engagement during climate resilience tool development, while more costly and time intensive, does lead to increased rates of diffusion and adoption of a climate resilience tool through both direct and indirect means. This work demonstrated that pre-development engagement to scope tool development is critical for maximizing relative benefit of a climate resilience tool. Additionally, all phases of engagement are necessary for both a useable and useful tool because each phase contributes to different attributes of the tool. Further research areas identified include understanding how much and what kind of stakeholder engagement is necessary to support continued diffusion and adoption after a tool is released, the role that mandates in climate resilience has on the adoption and diffusion of climate resilience tools, and how to define if a climate resilience tool has been successful.
232

The role of tourism in natural resource management in the Okavango Delta, Botswana.

Harrison, Phillipa Anne. January 2006 (has links)
In recent years the use of tourism as a development strategy by Third World governments has increased, resulting in the intersection of international tourism and local resource utilisation patterns. The aim of this thesis is to critically assess the impact of tourism in the utilisation and management of natural resources in the Okavango Delta in Botswana. More specifically, the study appraises the current state of tourism and natural resource utilisation and management in the Okavango Delta; assesses the past and present forms of resource utilisation practised by the local inhabitants scattered throughout the Delta area; focuses on the implementation of government policy regarding resource use; highlights past and present relationships between tourism and resource utilisation; and examines the impact of tourism on the areas resources, environment and local inhabitants. Research has shown that the Okavango Delta, which is Botswana's primary tourism area, is faced with a number of social, economic and environmental challenges. These include extreme levels of poverty, especially in the rural areas; lack of infrastructure; competition over land and resources; growing regional inequality; social degradation; increased imports leading to foreign exchange leakages; changes in subsistence strategies and increased 'rural-urban' .migration; and the loss of control of the region by the local population to the global tourism system. The Okavango Delta is in the process of undergoing a change from traditional, rural, subsistence economies and livelihoods to capitalist, commercial-driven economic structures. In the Okavango Delta, as in many places around the world, people are in the process of being integrated into national level political, social and economic institutions, both within and outside of their control. The creation of employment for the local population, the sustainable use of the Delta and its resources, the development of the local agricultural industry, the continued growth of the tourism industry, and striking a balance between the conservation/preservation of the Okavango and meeting the water requirement needs of Angola, Namibia, and Botswana's growing populations are amongst the key concerns present in the area. 11 Tourism in the Okavango Delta is directly dependent upon the utilisation of the region's natural resources of wildlife, water and natural vegetation areas for the industry. As such, tourism has increasingly impacted upon the way, and degree to which, these resources are managed and utilised, hence being identified as a key factor effecting the resource sector. If the Government of Botswana is to develop a tourism industry which fosters environmental and natural resource preservation, rather than maintaining a heavy dependence on limited and fragile resources, a better understanding of the relationship between the two sectors is necessary. Enhancing the positive linkages between tourism and natural resource utilisation in the Okavango Delta region represents an important means to stimulate increased natural resource and environmental protection, and improve the distribution of tourism benefits to rural communities. amongst the key concerns present in the area. Tourism in the Okavango Delta is directly dependent upon the utilisation of the region's natural resources of wildlife, water and natural vegetation areas for the industry. As such, tourism has increasingly impacted upon the way, and degree to which, these resources are managed and utilised, hence being identified as a key factor effecting the resource sector. If the Government of Botswana is to develop a tourism industry which fosters environmental and natural resource preservation, rather than maintaining a heavy dependence on limited and fragile resources, a better understanding of the relationship between the two sectors is necessary. Enhancing the positive linkages between tourism and natural resource utilisation in the Okavango Delta region represents an important means to stimulate increased natural resource and environmental protection, and improve the distribution of tourism benefits to rural communities. / Thesis (Ph.D.)-University of KwaZulu-Natal, Pietermaritzburg, 2006
233

Evaluation of the performance of community-based natural resources management (CBNRM) projects along an aridity gradient in Botswana

Mpofu, Khulekani January 2013 (has links)
The Botswana Community Based Natural Resources Management (CBNRM) programme started in 1989. Its aims were to promote sustainable development through sustainable natural resources management and utilisation to improve rural livelihoods. The country CBNRM programme has recorded mixed outcomes and this has raised questions on the programme performance throughout the country. Since the programme has been recognised as one of the eight main livelihood strategies for rural communities in Botswana, there was a need to evaluate the programme performance and determine the factors that influence it. This thesis therefore evaluated the performance of CBNRM projects along an aridity gradient in Botswana and by so doing answered the two research questions of: (1) What factors influence the performance of CBNRM? And (2) how does aridity influence the performance of CBNRM programmes? Performance was determined in terms of financial benefits generated by CBNRM projects and the projects adherence to the CBNRM principles. Data were collected from seven selected CBNRM projects covering three aridity zones (wet, medium rainfall and dry areas) in the country. Data were also collected from key informants and community based organisations (CBO) project managers. Research findings have indicated differences in the performance of CBNRM projects across the identified three aridity zones. Factors that influenced the performance of CBNRM projects varied among the three aridity zones. These factors included: existence of complimentary rules and regulations for managing CBNRM projects; literacy levels of communities involved in CBNRM; ethnic composition of the project communities; historic and current socio-economic trends within communities; collaboration between CBNRM institutions and other local level institutes; amount of benefits generated through the projects; ability of institutions to resolve outstanding issues in time and type of CBNRM project. Research results also indicated that there was variation in the performance of CBNRM projects across the three aridity zones. Aridity was found to directly influence the performance of CBNRM projects through its influence on the amount of revenues that projects generated.
234

Organisasie-innovasie vir omgewingsbestuur

Ward, Willie (Willem Jacobus) 12 1900 (has links)
Thesis (MA)--University of Stellenbosch, 2002. / ENGLISH ABSTRACT: The complexity of environmental problems and the demands that these make on organisations to create integrated management outcomes in a participative way in a multilevel context with many role-players, have highlighted the search for new innovative organisational forms. Organisations have specific structural characteristics with regard to complexity, formalisation and (de)centralisation, that correspond with their core activities and their external circumstances. The traditional bureaucracy, as an organisational structure, is a rigid and hierarchical system that is based on formal rules, complex management systems and centralised decision-making. The spread of postmodernism highlighted the restrictions of bureaucracies and started a process, throughout the world, that is transforming organisations into flatter, less formal structures. The focus of this study was to determine to which extent organisations in the field of sustainable development adapt to new realities and experiment with innovative organisational forms. Greenpeace, as an international environmental organisation, a Representative Forum, as an Agenda 21 type institutional mechanism for interest groups in the integrated development planning processes at local government level, and Water Catchment Management Agencies, as organisational institutional form for the integrated management of all aspects with regard to water resources, were analysed as case studies. The case studies confirm the increase in and application of multilevel network type organisational forms in the field of natural resources management. It highlights a common vision, processes that work towards reaching consensus and the forming of partnerships. The rise of the network organisation, its advantages and potential problems, are finally discussed with a view to the future. / AFRIKAANSE OPSOMMING: Die kompleksiteit van omgewingprobleme en die vereistes wat dit stel aan organisasies om op 'n deelnemende wyse in 'n multivlak en multi-rolspeler konteks ge·'ntegreerde bestuursuitkomste te bewerkstellig, het die fokus op die soeke na nuwe innoverende organisasievorme laat val. Organisasies het bepaalde strukturele eienskappe in terme van kompleksiteit, formalisasie en (de)sentralisasie wat grootliks aanpas by hulle kernbedrywighede en die eksterne omstandighede waarin hulle hulself bevind. Die tradisionele burokrasie as organisasievorm is 'n rigiede en hierarqiese sisteem wat geskoei is op sentrale besluitneming, formele reels en komplekse bestuurstelsels. Met die koms van postmodernisme het die beperkinge van die reuse burokrasiee aan die lig gekom en is daar, regoor die wereld, 'n proses aan die gang gesit wat talle organisasies in platter, minder formele en losser strukture verander. In die studie is ondersoek ingestel tot watter mate organisasies in die veld van volhoubare omgewingsbestuur by die nuwe realiteite aanpas en met nuwe innoverende organisasievorme eksperimenteer. Greenpeace, as internasionale omgewingsorganisasie, 'n Verteenwoordige Forum as Agenda 21-tipe institusionele meganisme vir belangegroepe in die geYntegreerde ontwikkelingsbeplanningsprosesse op plaaslike regeringsvlak, en Wateropvanggebied-bestuursagentskappe as organisatoriese institusionele vorm vir die qemteqreerde bestuur van aile aspekte wat met waterhulpbronne te make het, is as gevallestudies ontleed. Die gevallestudies bevestig die toenemde voorkoms en aanwending van multivlak netwerk-tipe organisasievorme op die gebied van natuurlike hulpbronbestuur wat die klem laat val op 'n samebindende visie, konsensus-soekende prosesse en venootskapsvorming. Die opkoms van die netwerkorganisasie met sy voordele sowel as die potensiele probleme, word ten slotte in 'n toekomsblik beskou.
235

The values of recycling, resources and risk management in Hong Kong

Wong, Wai-han, Mimi., 黃惠嫻. January 1998 (has links)
published_or_final_version / Environmental Management / Master / Master of Science in Environmental Management
236

Factors Affecting Wood Fuel Consumption and Environmental Impacts in Warren County, Kentucky

Vann, Barry 01 August 1990 (has links)
The purpose of this research is to identify factors that contribute to wood fuel consumption as a space heating source and estimate a county-wide proportion for wood fuel consuming households. In addition, environmental problems associated with deforestation such as erosion and loss of wildlife habitat are delineated; moreover, air pollution resulting from wood fuel emissions are discussed. An exhaustive literature review provided the basis for the study. Data on Warren County wood fuel consumption patterns were derived from a mail survey. Proportion estimates were tested by using a classical two-tail test of hypothesis. Subsequently, factors were identified and used in a multiple regression analysis. The study found that low income households equipped with electric space heating systems located in rural areas are the most wood intensive. Unlike homes equipped with other alternate heating systems, electric space heat equipped households tend to consume wood fuel proportionally to income. The study also found that 26.3 percent of single family residences in the county use wood for space heating.
237

Short-term Effects of Nutrients on a Barrier Island Grassland Community

Moulton, Ashley 01 January 2017 (has links)
Increased nutrient availability globally has the potential to affect community functional composition of plants in nutrient limited environments, such as coastal grassland systems. Stability of these systems are threatened worldwide by urbanization, as well as effects of sea level rise and increased frequency and intensity of storms, and atmospheric N deposition, associated with climate change. Annual net primary productivity (ANPP), species composition, and functional traits (community weighted specific leaf area (CWSLA), leaf area index (LAI), growth form and photosynthetic pathway) were measured across four treatments to assess multiple resource limitation of nitrogen (N) and phosphorus (P) and functional community response in a coastal grassland on Hog Island, VA within the Virginia Coast Reserve, Long Term Ecological Research Network (LTER) applied at a rate of 10 g m-2 yr-1 Nutrient enrichment did not alter species diversity or richness. ANPP was highest in plots receiving any type of nitrogen enrichment, and was higher than expected of low nutrient systems. CWSLA was significantly higher in NP plots, and was lower than other grasslands. P treatments were not significantly different from controls. Graminoid species, specifically C4 species responded with higher ANPP than C3 forbs or graminoids within treatments. Evidence of synergistic NP effects were seen on community level resource allocation and leaf construction, but no significant species changes occurred over a 1-year time span. These results have expanded the knowledge of functional response to increased nutrient availability in an understudied, coastal grassland, which are at high risk to being lost to sea level rise and anthropogenic development and inform community assembly processes in stressful environments.
238

Connecting Landscapes to People: Assessing the Distribution of Ecosystem Service Flows Using the SPAN Approach

Johnson, Gary Wayne 01 January 2014 (has links)
The Service Path Attribution Network (SPAN) framework provides a novel, user-centric, connectivity-based approach to ecosystem service assessment and valuation (ESAV). Ecosystem services are delivered to users through the simulated flow of some service medium (i.e., matter, energy, or information) from the ecosystems in which it originates (sources) to the people or assets which it affects (users). Along the way, the service medium may be absorbed by intervening landscape features (sinks) or captured by rival users. Crucially, the service medium is not itself an ecosystem service or benefit but rather an agnostic transport mechanism which establishes connectivity between sources, sinks, rival users, and nonrival users within a delimited study region. Each user then receives benefits or harm from the encountered service medium depending on their specific relationship with it. For example, if surface water is the simulated service medium, it may increase productivity at a hydropower plant but damage farmers in floodplains by drowning their crops. In the SPAN terminology, sources provide provisioning ecosystem services to users with a beneficial relationship with the service medium. Similarly, sinks provide preventive ecosystem services to users with a detrimental relationship with the service medium by reducing the amount flowing to their locations. Notably, within a single SPAN analysis, both sources and sinks may provide ecosystem services given a sufficiently heterogeneous pool of users. The results of a SPAN ESAV analysis are myriad, totalling up to 30 output maps for some services. Taken together, these maps tell the story of which sources provide services to which users, which sinks protect users from harm, which users compete for the same resources (and who wins), and how all of the sources, sinks, rival users, and nonrival users affect one another. Additionally, a SPAN simulation produces maps of the flow paths taken by the service medium from sources to users as well as where and by how much the flow strength is reduced by sinks. Studying these flow paths can help decision makers identify those locations at which management actions would be maximized or minimized depending on their specific development goals. A crowning achievement of this work is that for most ecosystem services the SPAN algorithm's complexity is guaranteed to be linear O(n) in both time and space with respect to the number of discrete locations analyzed. This makes it a viable option for high resolution landscape level ESAV studies using no more than commodity hardware. This dissertation explores the SPAN framework in depth, from its novel conceptual terminology and computational algorithms through to the intended interpretation of its results. In addition to describing the conceptual and mathematical components of this system in detail, this work also provides a complete Literate Program demonstrating the application of the SPAN framework to an assessment of the scenic beauty ecosystem service in Chittenden County, Vermont.
239

Long-term forest carbon storage and structural development as influenced by land-use history and reforestation approach

Urbano, Andrea Rose 01 January 2016 (has links)
Temperate forests are an important carbon sink, yet there is uncertainty regarding land-use history effects on biomass accumulation and carbon storage potential in secondary forests. Understanding long-term biomass dynamics is important for managing forests as carbon sinks and for co-benefits such as watershed protection and biodiversity. However there are many unanswered questions regarding these dynamics in northeastern U.S. forests: How have secondary forests of the U.S. Northeast recovered post nineteenth century agricultural abandonment? How has the region's extensive land-use history influenced long-term structural development and aboveground carbon storage? To answer these questions, we employed a longitudinal study based on twelve years of empirical data (2001-2013) from the Marsh-Billings-Rockefeller (MBR) National Historical Park in Woodstock, VT. MBR Park was the first parcel of land to actively be reforested in the eastern U.S., and as such, its diverse forest mosaic reflects a history of alternate reforestation approaches and varied successional trajectories indicative of secondary forest recovery occurring across the broader northeastern forest landscape. We also used 150 years of documentary data from park management records. This research evaluates the effects of reforestation approaches (planting vs. natural regeneration), management regimes (long-term low-to-intermediate harvest intensities at varied harvest frequencies), and stand development pathways on biomass outcomes. We generated biometrics representative of stand structural complexity, including the H' structural diversity index, and aboveground biomass (live trees, snags, and downed coarse woody debris pools) estimates. Multivariate analyses evaluated the predictive strength of reforestation approach, management history, and site characteristics relative to aboveground carbon pools and stand structural complexity. Classification and Regression Tree (CART) analysis ranked reforestation approach (plantation or natural regeneration) as the strongest predictor of long-term mean total aboveground carbon storage, while harvest frequency, and stand age were selected as secondary variables. CART ranked forest percent conifer (a metric closely associated with reforestation approach) as the strongest predictor of H' index, while harvest intensity, and harvest frequency were selected as secondary variables. Increases in harvest intensity can significantly reduce aboveground carbon storage. Our results suggest that a variety of long-term recovery pathways converge on high levels of aboveground carbon storage, including both conifer plantations and naturally regenerated hardwood stands, but choice of silvicultural management approach can dramatically alter those trajectories. Importantly, total aboveground biomass (i.e., carbon) co-varied with H' (r2 = 0.25), and thus, our dataset showed a positive relationship between forest carbon storage and structural complexity, supporting the concept of multifunctional forestry emphasizing late-successional habitats.
240

Phosphate Removal and Recovery from Wastewater by Natural Materials for Ecologically Engineered Wastewater Treatment Systems

Curran, Daniel Thomas 01 January 2015 (has links)
Eutrophication due to excess loading of phosphorus (P) is a leading cause of water quality degradation within the United States. The aim of this study was to investigate P removal and recovery with 12 materials (four calcite varieties, wollastonite, dolomite, hydroxylapatite, eggshells, coral sands, biochar, and activated carbon. This was accomplished through a series of batch experiments with synthetic wastewater solutions ranging from 10-100 mg PO₄-P/ L. The results of this study were used to establish large-scale, calcite-based column filter experiments located in the Rubenstein School of Environment and Natural Resources' Eco-Machine. Influent and effluent wastewater samples were routinely collected for 64 days. Measures of filter performance included changes in pH, percent reduction and mass adsorbed of P. After the columns reached saturation, filter media was analyzed for the mineralogical content by X-ray powder diffraction (XRD). In the batch experiments, P removal and recovery varied among the media and across treatments. The best performing minerals were calcite, wollastonite, and hydroxylapatite. Eggshells, activated carbon, and coral sands also reduced and adsorbed P. The remaining materials had the lowest reductions and adsorption of P. Results from batch experiments informed the design of large column filters within the Rubenstein School of the Environment and Natural Resources' Eco-Machine. Removal and adsorption rates of P by the three column filters were similar. The columns achieved an average P reduction of 12.53% (se = 0.98) and an average P adsorption of 0.649 mg PO₄-P/ kg media (se = 0.03) over a 4-h hydraulic retention time. Paired T-tests showed that P reductions were statistically significant (p-value < 0.05) on the majority of sampling dates until the columns reached saturation. Saturation was reached after 31 days for two of the columns and 36 days for the third column. The filter media consistently buffered the pH of the wastewater to approximately 6.0-7.0 with no indication of diminishing buffer capacity after saturation. XRD analysis was not able to detect any P species within the crystalline structure of the filter media. This research contributes to the understanding of how the selected media perform during P removal and recovery programs, while providing information on the performance of large column filters operating within advanced, ecologically engineered wastewater treatment systems.

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