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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.
211

Modeling the impact of buffer strips on phosphorus concentration in Buck Creek Watershed, Indiana : a GIS approach

Gopinath, Raju 29 June 2011 (has links)
This study has attempted to model and quantify the impacts of Beneficial Management Practices (BMP) like buffer strips on the phosphorus concentration and loading in the Buck Creek Watershed of Central Indiana. The GIS based modeling was done using the Soil and Water Assessment Tool (SWAT) developed by the U.S. Department of Agriculture-Agricultural Research Services (USDA-ARS). The results from the EPA funded two year (2002-2004) Upper White River Watershed Project (UWRWP) for the Buck Creek Watershed were used as the measured base data for the modeling evaluation. These measured data were compared against the data generated out of the model simulation based on two different scenarios which took into consideration the combinations of land use, agricultural management practices, point source pollutions and BMPs. Scenario-1 simulated all the aspects of land use intensity, moderate agricultural management practices and moderate point source pollutions taking place in the Buck Creek watershed. While running the model in scenario-1, there was a noticeable increase in the phosphorus loading to the sub-watersheds ranging from 10% in the lowland sub-watershed of BC-4 to 39% in the highland sub-watershed of BC-7. In scenario-2, BMPs were implemented in the model which added 100 acres of vegetated buffer strips uniformly in all sub-watersheds and 3 acres of grassed buffers along the streams except BC-3. On re-running the model in scenario-2, there was a drastic decline in the phosphorus loading to the stream. It has been noted that there was at least 15% reduction in the loading of phosphorus to the stream where buffer strips were implemented. The present GIS modeling study helped to quantify the changes in the loading of sediments and nutrients which are induced by any parametric changes in the watershed including soil, slope, land use, agricultural management practices and BMPs. / Department of Geography
212

Assessment of the long-term response to rehabilitation of two wetlands in KwaZulu-Natal, South Africa

Cowden, Craig January 2018 (has links)
Assessing the outputs and outcomes of wetland rehabilitation activities is recognised by the 'Working for Wetlands' programme in South Africa as important, but to date has been limited. An assessment of the ecological outcomes and the structural outputs of the Working for Wetlands rehabilitation implemented in the Killarney and Kruisfontein wetlands, KwaZulu-Natal, in 2005 was undertaken. The assessment of outcomes included an evaluation of the changes in terms of ecological integrity and the supply of ecosystem services, using WET-Health and WET- EcoServices assessment techniques respectively, and vegetation composition. Improvements in hydrological and geomorphic integrity were recorded in both wetlands, resulting in improved ecosystem services delivery. However, investigation of vegetation composition using the Wetland Index Value and Floristic Quality Assessment Index showed that, seven years after rehabilitation, KiNamey's vegetation composition had improved, but Kruisfontein's vegetation was still largely dominated by pioneer species and appeared to be stable, but in a severely transformed state. The response of these wetlands has shown that sites for rehabilitation should be screened before work begins, and wetlands requiring intensive management of vegetation recovery should be assessed in terms of the objectives and the anticipated benefits of the project. The assessment of the outputs included an evaluation of structural integrity, survival and cost- effectiveness. Limited issues, mostly relating to deviations from the designs during construction, were identified with regards to the structural outputs at each of the wetlands. However, the spreader canals at both Killarney and Kruisfontein wetlands were not functioning as intended and concentrated flows from the spreader canals were evident in both wetlands. The use of spreader canals should therefore be carefully planned and implemented for future wetland rehabilitation projects. Consideration of ZAR per hectare equivalent re-instated/secured provided a useful initial means of determining the cost-effectiveness of the wetland rehabilitation. However, additional factors need to be considered, such as, the nature of the rehabilitation activities, the type and size of the problem being addressed, rehabilitation of priority wetlands, limitations imposed by funders, and risks that need to be addressed by the rehabilitation strategy. Furthermore, the evaluation of the Killarney and Kruisfontein wetlands highlighted the need to revise the Water Research Commission's Wetland Management Series, especially those documents or guidelines relating to rehabilitation planning (WET-RehabPlan), interventions (WET-RehabMethods), and monitoring and evaluation (WET-RehabEvaluate).
213

A comparison of ecosystem health and services provided by subtropical thicket in and around the Bathurst commonage

Stickler, Meredith Mercedes January 2010 (has links)
Municipal commonage in South Africa offers previously disadvantaged, landless residents access to both direct ecosystem goods and services (EGS) that provide additional income options and indirect social and cultural services. Given that EGS production is a function of ecosystem health, it is imperative that commonage land be managed to maximize current local benefit streams while ensuring future options through the maintenance of natural ecosystem functions. The payments for ecosystem services (PES) model potentially offers an opportunity for contributing to local economic development while providing fiscal incentives for environmentally sustainable natural resource management. PES depends on the demonstration of quantifiable changes in EGS delivery due to improvement in or maintenance of high ecosystem health that are a verifiable result of modifications in management behavior. This thesis therefore compared spatial variations in (i) ecosystem health and (ii) nine direct and indirect EGS values derived from natural resources on the Bathurst municipal commonage and neighboring Waters Meeting Nature Reserve (NR) to explore how different land use intensities affect ecosystem health and the resulting provision of EGS. The results indicate that the total economic value of annually produced EGS on the study site is nearly R 9.8 million (US$ 1.2 million), with a standing stock of natural capital worth some R 28 million (US$ 3.4 million). Nearly 45% of the total annual production is attributed to Waters Meeting NR, with roughly 34% from the low use zone of the commonage and the remaining 22% from the high use zone. Of the total annual production value on the study site, roughly 59% is derived from indirect (non-consumptive) uses of wildlife for the study site as a whole, though this proportion varies from 25% in the high use zone of the commonage to 94% on Waters Meeting NR. The two largest annual production values on the study site derive from ecotourism (R 3.5 million, US$ 0.4 million) and livestock production (R 2.6 million, US$ 0.3 million), suggesting that while increased production of indirect EGS could generate significant additional revenues, especially on Waters Meeting NR and in the low use zone of the commonage, direct (consumptive) EGS will likely remain an important component of land use on the commonage. A PES project to support the adoption of silvo-pastoral practices could provide positive incentives for improved land use practices on the commonage and potentially be financed by conservation-friendly residents of the Kowie River catchment and/or increased ecotourism revenues from Waters Meeting NR. Allowing carefully designed and monitored local access to natural resources within Waters Meeting NR could also reduce pressure on commonage resources. Together, these approaches could lead to a more sustainable subtropical thicket landscape and ensure that critical natural resources remain available to support local livelihoods in the long-term.
214

Análise bioeconômica do seqüestro florestal de carbono e da dívida ecológica: uma aplicação ao caso do Rio Grande do Sul / .

Giacomelli Sobrinho, Valny 03 December 2007 (has links)
Though heavily criticized, the Kyoto Protocol has stood out as the key political tool in addressing climate change. However the only of its instruments (IET, JI, CDM) that allows industrialized and developing countries to cooperate towards mitigation of GHGs is CDM. The underlying assumption of forestry CDM is that forest plantations (afforestation/ reforestation) might help to remove carbon dioxide (the most representative GHG) emissions. This assumption takes for granted that forest plantations might compensate for the loss of natural forests. Therefore this alleged trade-off constitutes the very focus of this study. Due to high monetary price instability in brand new markets, like the carbon offset one, the analysis abstracts out money variables. Additionally, this engine helps overcome the trap set up by monetary prices as scarcity indicators. Thus, to go along with the bioeconomic analysis, a Gordon-Schaefer fishery-like model is applied to carbon forest sequestration in Rio Grande do Sul. This state is thought of bringing an interesting picture to the analysis of the claimed trade-off between natural and planted forests. This owes both to Rio Grande do Sul s unworthy deforestation rates and to its high natural-to-planted forest ratio. This land use assortment is thought of as if there were two countries or regions: a forest-rich one, where natural forests still remain, and a forest-poor one, where afforestation and/or reforestation takes place. Only physical units (MtC) are used to calculate exchange and interest rates as well as non-monetary prices. Next, a function that assigns the land use to natural and planted forests is arrived at. As such, it works as the emission removal demand. On the other hand, the emission supply function depends on the economic growth rates. The results show that, eventually, the sustainability of economic growth hinges on a region s or country s ecological situation namely, equilibrium, credit or debt. The economic and environmental advantages of each mitigation strategy CDM and natural forest conservation are crosschecked. A nearly 40-year long overshoot rate is, after all, estimated for the forest sector in Rio Grande do Sul. The estimates suggest that CDM might help relieve environmental stress only where ecological credit is reported. Where ecological debt is already on, CDM was found unable to compensate for conservation disregard. / Apesar das críticas que tem sofrido, o Protocolo de Kyoto tem-se constituído na principal ferramenta política para enfrentar a mudança climática. No entanto o único de seus instrumentos (comércio internacional de emissões, implementação conjunta e MDL) que prevê a cooperação entre países industrializados e em desenvolvimento para mitigar as emissões de GEE é o MDL. A modalidade florestal do MDL pressupõe que as plantações florestais (florestamento/reflorestamento) podem ajudar na remoção das emissões de dióxido de carbono (o GEE mais representativo). Esse pressuposto aceita que as plantações florestais podem compensar a perda de florestas naturais. Por isso esse proclamado trade-off constitui o foco principal deste estudo. Devido à grande instabilidade dos preços monetários em mercados incipientes como o do carbono, a análise abstém-se de utilizar variáveis monetárias. De resto, esse artifício ajuda a contornar certas dificuldades decorrentes da utilização dos preços monetários como indicadores de escassez. Assim, a análise bioeconômica prossegue com a aplicação, ao seqüestro florestal de carbono no Rio Grande do Sul, de um modelo similar ao de Gordon-Schaefer, tradicionalmente empregado na gestão da pesca. Por duas razões principais, o caso do Rio Grande do Sul contribui para a análise do suposto trade-off entre florestas naturais e plantadas. Em primeiro lugar, por não se registrarem taxas de desmatamento pronunciadas no estado. Em segundo lugar, pela elevada proporção de florestas naturais em relação às florestas plantadas em seu território. A repartição do uso do solo entre as florestas é utilizada para estudá-las como se representassem nações ou regiões diferentes: uma, rica em florestas, onde as formações florestais nativas permanecem em pé; outra, pobre em florestas, onde as plantações florestais se estabelecem através de florestamento e/ou reflorestamento. Apenas unidades físicas (MtC) são utilizadas para calcular taxas de câmbio, taxas de juro e preços não-monetários. A seguir, deduz-se uma função que reparte o uso da terra entre florestas naturais e plantadas. Essa função equivale à demanda por remoção de emissões. Sua contraparte é a função oferta de emissões, que depende das taxas de crescimento econômico. Os resultados mostram como, em última análise, a sustentação do crescimento econômico está condicionada à situação ecológica (dívida, crédito ou equilíbrio) de um país ou região. Em cada cenário, confrontam-se as vantagens econômicas e ambientais das estratégias do MDL e da conservação de florestas naturais. Além disso, estima-se uma taxa de overshoot para a atividade florestal no Rio Grande do Sul ao longo dos últimos 40 anos aproximadamente. As estimativas sugerem que o MDL pode aliviar pressões ambientais somente onde se registre crédito ecológico. Onde o endividamento ecológico já esteja em curso, o MDL não substitui a conservação.
215

The role of acute toxicity data for South African freshwater macroinvertebrates in the derivation of water quality guidelines for salinity

Browne, Samantha January 2005 (has links)
Water resources are under ever-increasing pressure to meet the demands of various water users both nationally and internationally. The process of anthropogenically-induced salinisation serves to exacerbate this pressure by limiting the quantity and quality of water available for future use. Water quality guidelines provide the numerical goals which water resource managers can use to adequately manage and protect aquatic ecosystems. Various methods which have been developed and used internationally to derive such guidelines are discussed. Acute toxicity tests were conducted using two inorganic salts, NaCl and Na₂SO₄. Field collected, indigenous, freshwater macroinvertebrates were used as tests organisms. Data generated from these tests contributed to the expansion of the currently limited toxicological database of response data for indigenous organisms and the suitability of using such organisms for future testing was discussed. Salt sensitivities of indigenous freshwater invertebrates were compared those of species sourced from an international toxicological database and were found to have similar ranges of tolerances to NaCl and Na₂SO₄. Species sensitivity distributions (SSDs), a method of data extrapolation, were derived using different types of toxicological data, and hence different guideline values or protective concentrations were derived. These concentrations were equated to boundary values for South Africa’s ecological Reserve categories, which are used to describe degrees of health for aquatic ecosystems. Provisional results suggest that using only acute toxicity data in guideline derivation provides ecosystem protection that is under-protective. Chronic toxicity data, which include endpoints other than mortality, provide the most realistic environmental protection but lack data confidence due to small sample sizes (acute tests are more readily conducted than chronic tests). The potential contribution of sub-chronic data to guideline derivation is highlighted as these data are more readily extrapolated to chronic endpoints than acute data and sub-chronic tests are not as complex and demanding to conduct as chronic tests.
216

The implication of fuel-wood use and governance to the local environment: a case study of Ward Seven of Port St Johns Municipality in the Eastern Cape

Ndamase, Zola January 2012 (has links)
The importance of ecological systems in supporting social systems has been identified as one of the most important facets of sustainable development. Consequently, a number of international and local laws and policy interventions have been established to ensure that natural resource use remains sustainable. In rural areas, overdependence on fuel wood has commonly been identified as one of the biggest threat to forestry ecosystems. This in turn has led to environmental degradation that includes among others species depletion, soil erosion and decline in water and air quality. Based on the myriad problems caused by over-reliance on fuel wood, this study sought to identify usage, management and perceived implication of woodland exploitation in Port St Johns local municipality in the Eastern Cape, South Africa. Using interviews and questionnaires for key respondents in the local community, the study identified two key threats to socio-ecological stability resulting from wood fuel exploitation namely; high poverty levels and lack of coordination in the management of wood fuel resources. Apart from using fuel wood for domestic use, local fuel wood exploitation has been commercialized to augment household incomes. Lack of coordination in the management of natural resources has also created a vacuum in the exploitation and management of fuel wood resources. The study did not have inclination towards statistics such as chi-square and t-tests since the research questions and objectives did not refer to any relationship or significance level. The study recommends non-wood based alternative sources of energy, improved coordination and harmonization of functions among different stakeholders and emphasis on collaboration between traditional and local governance in the management fuel wood and the local physical environment. The study further recommends resuscitation of indigenous knowledge and socio-ecological stability
217

Conhecimento ecológico caiçara sobre animais silvestres como aporte para um manejo de base ecossistêmica / Caiçara's ecological knowledge about wild animals as input to an ecosystem-based management

Islas, Camila Alvez, 1991- 27 August 2018 (has links)
Orientador: Cristiana Simão Seixas / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-27T06:11:01Z (GMT). No. of bitstreams: 1 Islas_CamilaAlvez_M.pdf: 6133137 bytes, checksum: ebdb2978dff83f18d49a9a85333257f8 (MD5) Previous issue date: 2015 / Resumo: Nesta dissertação investiguei o Conhecimento Ecológico Tradicional (CET) sobre a fauna silvestre em uma comunidade Caiçara, localizada dentro de uma Unidade de Conservação (UC) de proteção integral, para gerar informações para o manejo de fauna dentro da reserva e em Unidades de Conservação brasileiras, incorporando princípios das abordagens de Manejo de Base Ecossistêmica e Ecossystem Stewardship. Este estudo foi realizado na comunidade da Praia do Sono, situada dentro da Reserva Ecológica Estadual da Juatinga (REEJ), no município de Paraty, RJ, que atualmente passa por um processo de recategorização para adequar-se à legislação federal, o que pode modificar a relação das comunidades com os recursos de subsistência, como os animais silvestres. Além disso, teorias e abordagens de manejo de recursos naturais poderão ser incorporadas ao novo plano de manejo. Para a coleta de dados realizei quatro conjuntos de entrevistas: i) entrevista semiestruturada, com 39 unidades familiares da Praia do Sono, para investigação dos usos, interações negativas e conservação da fauna na comunidade; ii) entrevista estruturada, com 7 informantes-chave da comunidade, para correlação entre os nomes populares e científicos iii) entrevista semiestruturada, com 4 informantes-chave da comunidade, para investigação do CET sobre biologia da fauna silvestre; e iv) entrevista semiestruturada, com 10 funcionários da REEJ, para compreender sua visão sobre a gestão de recursos na reserva. Utilizei também conversas não planejadas e observação direta. Na comunidade da Praia do Sono, os animais silvestres são utilizados principalmente como alimento, mas também como remédio e estimação. As interações negativas são motivadas por prejuízos que ocorrem na agricultura, na criação de animais domésticos, à saúde e por lazer. Após análise dos dados, os animais apontados como relevantes para o manejo da reserva, devido a suas características cinegéticas, seu potencial de gerar interações negativas ou por suas flutuações populacionais, são os mamíferos: paca (Cuniculus paca), cutia (Dasyprocta leporina), gambá (Didelphis sp.), tatu (Dasypus sp.), coati (Nasua nasua), veado (Mazama americana), porco-do-mato (Pecari tajacu), macaco-prego (Sapajus nigritus) e jaguatirica (Leopardus sp.); as aves: jacu (Penelope obscura), macuco (Tinamus solitarius), e tucano (Ramphastos sp.); e o réptil lagarto-teiú (Tupinambis merianae). Ainda, foram encontrados apetrechos, técnicas e regras de Caça Caiçara que devem, especialmente, serem considerados na gestão da Reserva. O CET encontrado é bastante robusto e possui potencial para ser utilizado no manejo da UC, pois contém uma gama valiosa de informações sobre os animais silvestres. Nesse contexto, o uso da abordagem Manejo de Base Ecossistêmica para a elaboração de um plano de manejo pode trazer benefícios para a REEJ e para outras UCs brasileiras, devido a proposta de integração do CET as informações técnico-científicas e a visão sistêmica da abordagem. A estratégia Ecosystem Stewardship complementa a abordagem de Manejo de Base Ecossistêmica ao propor uma gestão "de baixo para cima", na qual os usuários dos recursos seriam os maiores responsáveis pelo seu cuidado e garantia de sua sustentabilidade. Afinal, as interações entre a população humana local e a fauna vem se modificando, apresentando distintas formas de compreender a conservação. Ao reconhecer que as populações tradicionais necessitam utilizar os recursos naturais para viabilizarem sua existência serão encontrados usos e interações negativas danosas aos ecossistemas, mas também soluções para o manejo desses recursos. É na construção junto as comunidades que é possível encontrar respostas para a conservação, e o Conhecimento Ecológico Tradicional mostrou-se um valioso aliado nessa caminhada / Abstract: Here I have investigated the Traditional Ecological Knowledge (TEK) on wild animals in a Caiçara community, located within a full protected area (PA), to generate information for the wildlife management in the reserve and in Brazilian protected areas, incorporating principles of Ecosystem-based Management and Ecosystem Stewardship approaches. This study was conducted in Praia do Sono¿s community, located within the Juatinga State Ecological Reserve (JSER) in Paraty municipality, Rio de Janeiro state, which is currently undergoing a re-categorization process to adapt to federal legislation, which may modify the relationship of communities with subsistence resources like wild animals. In addition, theories and management approaches to natural resources could be incorporated into the new management plan. For data collection I conducted four groups of interviews: i) semi-structured with 39 Caiçara family¿s units, to investigate uses, negative interactions and conservation of fauna in the community; ii) structured interviews, with seven key informants of the community, for correlation between popular and scientific names; iii) semi-structured interviews with four key informants of the community, to investigate TEK on biology of wildlife; and iv) semi-structured interviews with 10 JSER employees, to understand their view on resource management in the Reserve. I also used unplanned conversations and direct observation. In Praia do Sono¿s community, wild animals are mainly used as food sources, but also as medicine and pets. Negative interactions occur motivated by losses in agriculture and animal husbandry, as well due to fear of attack and leisure. After analyzing the data, the animals identified as relevant to the management of the Reserve, due to their hunting characteristics, their potential to generate negative interactions or its population fluctuations are the mammals paca (Cuniculus paca), agouti (Dasyprocta leporina), opossum (Didelphis sp.), armadillo (Dasypus sp.), coati (Nasua nasua), brocket deer (Mazama americana), collared peccary (Pecari tajacu), capuchin monkey (Sapajus nigritus) and ocelot (Leopardus sp.); the birds: dusky-legged guan (Penelope obscura), solitary tinamou (Tinamus solitarius), and toucan (Ramphastos sp.); and the reptile: lizard-tegu (Tupinambis merianae). Still, Caiçara¿s hunting traps, techniques and rules were found and should especially be considered in the management of the reserve. The TEK found is robust and has potential to be used in the management of PAs because it contains a valuable range of information about the wildlife. In this context, the use of the Ecosystem Based Management approach for the development of a management plan can benefit the JSER and other Brazilian PAs due to the proposal of integration between TEK and technical and scientific knowledge and the systemic view of the approach. The Ecosystem Stewardship strategy complements Ecosystem-based Management approach whit its proposal of a "bottom-up" management, in which resource users are the most responsible for resource care and its sustainability ensuring. After all, interactions between local human population and fauna has been changing, with different ways of understanding conservation. Recognizing that traditional populations need to use natural resources to ensure their survival will highlight damaging uses and and negative interactions harmful to ecosystems, but may also be found solutions for manage resources. It is in the building with the communities that you can find answers for conservation, and the Traditional Ecological Knowledge proved to be a valuable ally in this journey / Mestrado / Ecologia / Mestra em Ecologia
218

Challenges affecting the management of Thulamela wetlands: managers engagement with local communities use of wetlands

Mukhuwana, Onica 10 1900 (has links)
MENVSC / Department of Ecology and Resource Management / Wetlands are amongst the world’s most important ecosystems providing many direct and indirect benefits to local communities. The majority of South Africans residing in rural areas depends mostly on natural resources for their livelihood. However, wetlands in South Africa continue to be the most threatened ecosystems primarily due to unsustainable use and poor resource management. Additionally, the history of South Africa has been characterised by exclusion of local communities in the process of decision-making and general management of natural resources. The aim of the study was to investigate possible challenges affecting the management of Thulamela wetlands by assessing the level of interaction and conflicting interest amongst participating stakeholders, including role of wetlands on local communities for possibly improved management scenarios. The study used questionnaires, interviews and observations to capture data on the local communities and management stakeholders. Seven wetlands within Thulamela were selected as study areas and the study population was selected based on their specialised expertise, involvement, and closeness to wetlands. Data was analysed using SPSS, Microsoft Excel and also using thematic analysis in NVIVO. The results show that selected wetlands are highly beneficial in supporting the local communities. Based on the socio-economic and demographic characteristics (family size, age, gender, and employment status) measured, the study deduced that unemployment rate or low income of the respondents is the main contributor to an increase dependency on wetland utilization. Additionally, the results revealed that unregulated use and excessive agricultural practices such as cultivation and livestock grazing are common in all study areas, hence further degradation of these wetlands. One of the findings from the study was the destruction of wetlands through expansion of human settlement. The population increase in the areas was found to be major drivers of socio-economic challenges causing people to spread through and exploit wetlands. Consequently, human settlement along the wetland area has resulted in the extensive clearance of natural wetland vegetation. Furthermore, the results show that there is poor wetland information transfer to the local communities most likely due to none/or insufficient outreach programmes. The current management arrangements and structures for selected wetlands are not being practiced through the unequal representation amongst management stakeholders and poor inclusion of local communities in management processes. Additionally, there are currently no openly known active platforms provided upon which stakeholders are able to air their views on wetlands management issues. The findings further show differences in perceptions amongst wetlands users, non-users and management stakeholders. The management stakeholders have a relatively strong focus on livelihood and environmental problems, they regard rules and regulations on wetland use’ as a relatively central variable. On the other hand, the local communities are currently more concerned about the benefits they receive from the wetlands than the conservation of those systems. The study also revealed unequal representation amongst participating management stakeholders. The findings show poor interaction between the management stakeholders and the local communities; differences in perceptions amongst resource users, non-users and managers; exploitation of wetlands resources; poor wetlands information transfer. The results suggest that centralised top-down rules and regulations on wetland use are not sufficient for maintaining the wetland ecosystem and this poses a challenge to sustainable wetland management. Therefore, there is a need to develop shared understanding through bottom-up approaches to wetland management that are nested within national regulatory frameworks, ideally combined with awareness building and knowledge sharing on the ecological benefits and management of wetland. / NRF
219

The Kunene River mouth : managing a unique environment.

Paterson, John Richard Bernard. January 2007 (has links)
The Kunene River Mouth (KRM) is one of only two river mouths in Namibia. The Kunene river and river mouth is bisected by the international border between Namibia and Angola, and lies between two protected areas, Iona National Park in Angola and Skeleton Coast Park in Namibia. The governments of Namibia and Angola have signed a Memorandum of Understanding (MoU) to link these two parks as a transfrontier park. This study further proposes a transfrontier Marine Protected Area to protect the marine environment surrounding the KRM and the Angola Benguela Front. The KRM is a fluvially dominated freshwater river mouth. The area is a biogeographically important biodiversity hotspot. The remoteness and pristine character contribute to the aesthetic appeal of the area. This study provides a profile of the KRM addressing its conservation value in terms of both biodiversity and aesthetic value, making use of the concept of “sense of place”. An analysis of all current and potential stakeholders is presented and their interests, activities and potential threats are evaluated. The main stakeholders are Government: the Ministry of Environment and Tourism, the Angolan Government, Ministry of Fisheries and Marine Resources, Namwater, Ministry of Mines and Energy, and the Kunene Regional Council. The private sector presently has a small stake in the area, with the exception of the Northern Namibia Development Corporation who is prospecting for diamonds at the KRM. Although the area has great tourism potential there is no tourism development currently underway or planned. The threat analysis suggests that the KRM is under severe threat from inappropriate development, both locally as well as within the catchment. Mining and prospecting were identified as the greatest threat, whereas tourism poses the least threat to the area. It is suggested that appropriate tourism is the most suitable development for this sensitive area. There is currently no coherent management strategy in place for the KRM. The current environmental legislation is ineffective. The need for a stringent adaptive management regime is identified and management goals for the area are suggested. It is further suggested that the concepts of “Thresholds of Potential Concern” and “Limits of Acceptable Change” are useful to monitor indicators for biophysical components and development activities respectively and to maintain a “Desired State” for the area. This “Desired State” must be the result of a participatory process. To be effective stakeholders must reach consensus on the “Desired State”. An eight step participatory process is proposed to develop and implement an adaptive management and development strategy for the KRM. / Thesis (M.Env.Dev.) - University of KwaZulu-Natal, Pietermaritzburg, 2007.
220

Remote sensing of leaf area index in Savannah grass using inversion of radiative transfer model on Landsat 8 imagery: case study Mpumalanga, South Africa

Masemola, Cecilia Ramakgahlele 03 1900 (has links)
Savannahs regulate an agro-ecosystem crucial for the production of domestic livestock, one of the main sources of income worldwide as well as in South African rural communities. Nevertheless, globally these ecosystem functions are threatened by intense human exploitation, inappropriate land use and environmental changes. Leaf area index (LAI) defined as one half the total green leaf area per unit ground surface area, is an inventory of the plant green leaves that defines the actual size of the interface between the vegetation and the atmosphere. Thus, LAI spatial data could serve as an indicator of rangeland productivity. Consequently, the accurate and rapid estimation of LAI is a key requirement for farmers and policy makers to devise sustainable management strategies for rangeland resources. In this study, the main focus was to assess the utility and the accuracy of the PROSAILH radiative transfer model (RTM) to estimate LAI in the South African rangeland on the recently launched Landsat 8 sensor data. The Landsat 8 sensor has been a promising sensor for estimating grassland LAI as compared to its predecessors Landsat 5 to 7 sensors because of its increased radiometric resolution. For this purpose, two PROSAIL inversion methods and semi- empirical methods such as Normalized difference vegetation index (NDVI) were utilized to estimate LAI. The results showed that physically based approaches surpassed empirical approach with highest accuracy yielded by artificial neural network (ANN) inversion approach (RMSE=0.138), in contrast to the Look-Up Table (LUT) approach (RMSE=0.265). In conclusion, the results of this study proved that PROSAIL RTM approach on Landsat 8 data could be utilized to accurately estimate LAI at regional scale which could aid in rapid assessment and monitoring of the rangeland resources. / Environmental Sciences / M. Sc. (Environmental Science)

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