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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.
361

Arable plant diversity in conventionally managed farmland of Northwest Germany - Current state and a participative approach to increase farmland biodiversity

Wietzke, Alexander 12 August 2020 (has links)
No description available.
362

Collaborative GIS process modelling using the Delphi method, systems theory and the unified modelling language (UML)

Balram, Shivanand January 2005 (has links)
No description available.
363

Response of endangered bird species to land‑use changes in an agricultural landscape in Germany

Jungandreas, Anne, Roilo, Stephanie, Strauch, Michael, Václavík, Tomáš, Volk, Martin, Cord, Anna F. 02 February 2024 (has links)
Land-use intensification in agroecosystems has led to population declines in many taxonomic groups, especially farmland birds. Two contrasting conservation strategies have therefore been proposed: land sharing (the integration of biodiversity conservation in low-intensity agriculture) and land sparing (the spatial separation of high-yielding agriculture and areas for conservation). Despite the large academic interest in this field, only few studies have taken into account stakeholders’ perspectives of these strategies when assessing conservation implications. We modeled the effects of three land-use scenarios (a business-as-usual, a land-sharing, and a land-sparing scenario), developed together with regional stakeholders, on the habitat area of 13 regionally endangered bird species in the Middle Mulde River Basin (Saxony, Germany). We used random forest models based on environmental variables relating to land-use/cover, climate and soil characteristics, occurrence of linear landscape elements (hedges and tree rows), and distance to water and major roads. Responses to the three land-use scenarios were species-specific, but extensively managed permanent grassland and the density of forest edges were positively associated with the occurrence of most bird species. Overall, the land-sharing scenario provided the largest breeding habitat area: 76% of the species had a significant (p < 0.05) increase in breeding habitat, and none showed a significant decrease. Our findings confirm that balancing the different, often contrasting habitat requirements of multiple species is a key challenge in conservation and landscape management. Land sharing, which local stakeholders identified as the most desirable scenario, is a promising strategy for the conservation of endangered birds in agricultural landscapes like our study region.
364

Herbarium Collections Management Internship

Harmon, Amanda Lauren Leslie 26 April 2018 (has links)
No description available.
365

An exploration of the impacts of socio-economic activities on the loss of biodiversity in the Maseru and Berea districts of Lesotho

Sekamane, Thabang 01 1900 (has links)
Text in English / Biodiversity is a fundamental characteristic of life on Earth and encompasses the whole range of variation in living organisms. Lesotho has been subjected to tremendous biodiversity change over the last two centuries, primarily due to socio-economic activities. A number of socio-economic factors have contributed to the loss of biodiversity. However, worldwide experience has shown that, the consequences emanating from loss of biodiversity are sometimes irreversible as some species are threatened by extinction. The study aimed at exploring the impacts of socio-economic activities that result in loss of large game animals, predators and indigenous plants species in Lesotho. To serve this objective, both quantitative and qualitative research methodologies were used to collect data. Quantitative research method was used in pre-post tests whilst qualitative research method was used in interviews and focus group discussions to collect data. The finding and results of the study show that, impacts of human vectors such as immigration, migration, settlement, economic and recreation activities in Lesotho have the impacts to the loss of large game animals, predators and indigenous plants. It is imperative therefore, for Lesotho to find ways to establish more parks and botanic gardens that could offer opportunities for re-introduction of species in Lesotho, thus, adding value to the existing parks. / Environmental Sciences / M. Sc. (Environmental Management)
366

Biodiversity enhancement in Cape Flats urban habitats

Faul, Andre Karel 12 1900 (has links)
Thesis (MSc (Conservation Ecology and Entomology))--University of Stellenbosc, 2005. / Biodiversity is under enormous pressure from an increasing human population. Urbanisation, agriculture, and mining are just some of the factors responsible for the continuous degradation of the natural environment. Of these, urbanisation is one of the leading factors of diversity loss. To address this problem, it is necessary to understand the relationship between biodiversity and urban areas, as well as the relationship between society and biodiversity. This study focuses on these relationships and suggest ways in which urban biodiversity can be maximised without compromising on development. In order to create an urban environment that successfully supports maximised biodiversity, new methods and ideas must be developed to promote the protection of urban ecosystems. The Cape Floristic Region in South Africa is a good example of an area that requires immediate action in order to prevent enormous losses in biodiversity. Data have shown drastic decreases in natural vegetation cover in this area, and with its close to 9000 species, of which approximately 60% occurs nowhere else in the world. This state of affairs should be regarded as a serious crisis. This study consists of three main parts, the first being a literature review on the current relationships between the urban environment, society, and biodiversity. The second and third parts report on two empirical investigations on the campus of the Faculty of Health Sciences at the University of Stellenbosch in the City of Cape Town. The first of these investigates the possibility of using spirituality connected to nature as a promotional tool for conservation through rehabilitation or restoration of damaged urban vegetation habitats. For this purpose students’ and staff members’ opinions of the urban nature at the campus were tested. In the second investigation the options of restoring biodiversity to the campus was considered by exploring the best options available for rehabilitation while taking the current biodiversity status on and around the premises into account. This was carried out through three smaller projects that included the physical reintroduction of plant species, vegetation analysis, and bird identification and attraction. The response of employees and students at the Faculty of Health Sciences was found to be in favour of restoring vegetation and animal life to the campus. This is supported by a belief that their attitude towards their work would improve with improved natural surroundings. Initial rehabilitation attempts highlighted the complexity of rehabilitation practices by bringing forward challenges and problems experienced with the reintroduction of plant species. Despite these problems, increased plant diversity in experimental areas showed the possibility of successfully completing the project. Biodiversity analysis showed that methods of controlling vegetation used by the university are doing more harm than good, as it results in indigenous vegetation being displaced by exotic vegetation. This study introduces a number of questions regarding the relationship between urbanisation and biodiversity and to what extent the two should be linked. Hopefully it is a step in the direction towards marrying the urban and natural environment, and to create a sustainable urban environment where society no longer sees nature as something outside the city boundaries.
367

An exploration of the impacts of socio-economic activities on the loss of biodiversity in the Maseru and Berea districts of Lesotho

Sekamane, Thabang 01 1900 (has links)
Text in English / Biodiversity is a fundamental characteristic of life on Earth and encompasses the whole range of variation in living organisms. Lesotho has been subjected to tremendous biodiversity change over the last two centuries, primarily due to socio-economic activities. A number of socio-economic factors have contributed to the loss of biodiversity. However, worldwide experience has shown that, the consequences emanating from loss of biodiversity are sometimes irreversible as some species are threatened by extinction. The study aimed at exploring the impacts of socio-economic activities that result in loss of large game animals, predators and indigenous plants species in Lesotho. To serve this objective, both quantitative and qualitative research methodologies were used to collect data. Quantitative research method was used in pre-post tests whilst qualitative research method was used in interviews and focus group discussions to collect data. The finding and results of the study show that, impacts of human vectors such as immigration, migration, settlement, economic and recreation activities in Lesotho have the impacts to the loss of large game animals, predators and indigenous plants. It is imperative therefore, for Lesotho to find ways to establish more parks and botanic gardens that could offer opportunities for re-introduction of species in Lesotho, thus, adding value to the existing parks. / Environmental Sciences / M. Sc. (Environmental Management)
368

Biogeografia da conservação frente à expansão agrícola: conflitos e prioridades / Conservation Biogeography faced with agricultural expansion: conflicts and priorities

DOBROVOLSKI, Ricardo 10 April 2012 (has links)
Made available in DSpace on 2014-07-29T16:23:34Z (GMT). No. of bitstreams: 1 Tese Ricardo Dobrovolski.pdf: 1981880 bytes, checksum: 8c60352c3d999171ab957f065b32a9db (MD5) Previous issue date: 2012-04-10 / Agriculture is the human activity with the greatest impact on the environment. Specifically, it represents the greatest threat to biodiversity. In the future, this activity should expand due to population growth, increased consumption and production of biofuels from food. To understand the possible impacts of this expansion on biodiversity, we used scenarios of land use change between 1970 and 2100 from IMAGE (Integrated Model to Access Global Environment) to test the following hypotheses: (i) areas considered as global priorities for conservation by international NGOs will be preferentially impacted by agricultural expansion in the XXI century, (ii) there is a conflict between the priority areas for carnivores conservation and agricultural expansion, and this conflict can be reduced by incorporating information on agricultural expansion in the prioritization process, (iii) the integration among countries for conservation planning may benefit both biodiversity and agricultural productivity, (iv) Brazilian protected areas will be impacted by agricultural expansion in the future and this impact will differ between protected areas of integral protection and those of sustainable use. We found that: (i) the impact on priority areas for conservation depends on the criteria by which they were set, so that areas defined by its high vulnerability are currently most affected than those of low vulnerability. Throughout the XXI century this impact is expected to increase, although the difference between the two types of priorities remains, except for High Biodiversity Wilderness Areas, defined by their low vulnerability in current time, but for which most pessimistic scenarios forecast an impact similar to priority areas of high vulnerability, (ii) there is a high spatial congruence between areas with high agricultural use in the future and priority areas for conservation of carnivores. This conflict can be reduced if the prioritization process include information on agricultural expansion; this incorporation, however, causes a profound change in the distribution of priority areas and reduces the number of protected carnivore populations, (iii) the integration of countries to create a set of priority areas for conservation that represents 17% of the land surface can protect 19% more mammal populations without reducing food production, compared to a strategy in which each country seeks to protect its territory independently, and (iv) the impact of agriculture in Brazil is expected to increase until the end of the century, threatening even the protected areas and their surroundings. This impact, however, should not be different between areas of sustainable use and those of integral protection. We conclude that agricultural expansion should remain a major threat to biodiversity in the future, even in areas of special interest for conservation. Conservation actions should be planned taking into account this threat in order to reduce their potential impacts. For this, countries like Brazil should strengthen its surveillance on agricultural expansion and on how this activity is developed. Furthermore, the integration of international conservation efforts should be pursued, given its benefits for biodiversity and food production. Finally, humanity must choose methods of agricultural production that reduce its impacts, including avoiding its future expansion, so as to meet the increasing needs of a human population globally. / A agricultura é a atividade humana com maior impacto sobre o ambiente. Particularmente, ela representa a maior ameaça à biodiversidade. No futuro, essa atividade deve expandir-se com o aumento populacional humano, o aumento do consumo e a produção de biocombustíveis a partir dos alimentos. Para entender os possíveis impactos dessa expansão sobre a biodiversidade, nós utilizamos cenários de mudança de uso do solo entre 2000 e 2100 do IMAGE (Integrated Model to Access Global Environment) para testar as seguintes hipóteses: (i) as áreas consideradas como prioridades globais de conservação pelas ONGs internacionais serão preferencialmente impactadas pela expansão agrícola no século XXI; (ii) há um conflito entre áreas prioritárias para a conservação de carnívoros e a expansão agrícola e esse conflito pode ser reduzido com a incorporação da informação sobre expansão agrícola no processo de priorização; (iii) a integração entre os países para o planejamento da conservação pode ser favorável à proteção da biodiversidade e à produção agrícola; (iv) no Brasil, as áreas protegidas serão impactadas pela expansão agrícola no futuro e esse impacto será diferente entre áreas de proteção integral e áreas de uso sustentável. Nós encontramos os seguintes resultados: (i) o impacto sobre as áreas prioritárias para a conservação depende dos critérios pelos quais elas foram definidas, assim, as áreas definidas por sua alta vulnerabilidade estão atualmente mais impactadas do que áreas de baixa vulnerabilidade. Ao longo do século XXI, o impacto geral da agricultura deve aumentar, mas a diferença entre os dois tipos de prioridades se mantém, exceto para as High Biodiversity Wilderness Areas, definidas por sua baixa vulnerabilidade, mas que nos cenários mais pessimistas podem ter um impacto agrícola semelhante ao das áreas de alta vulnerabilidade; (ii) há uma alta congruência espacial entre áreas com elevado uso agrícola no futuro e áreas prioritárias para a conservação de carnívoros; esse conflito pode ser reduzido se o processo de priorização incluir as informações sobre a expansão agrícola; a incorporação dessa informação, entretanto, provoca uma profunda alteração na distribuição das áreas prioritárias e reduz o número de populações de carnívoros protegidas; (iii) a integração entre os países para a criação de um conjunto de áreas prioritárias para conservação que represente 17% da superfície terrestre pode proteger 19% mais populações de mamíferos sem reduzir a produção de alimentos, se comparada a uma estratégia em que cada país busque proteger seu território independentemente; (iv) o impacto da agricultura no Brasil deve aumentar até o fim do século XXI, ameaçando inclusive as áreas protegidas e o seu entorno. Esse impacto, porém, não deve ser diferente entre as áreas de uso sustentável e aquelas de proteção integral. Assim, a expansão agrícola deve continuar a ser uma importante ameaça à biodiversidade no futuro, atingindo inclusive áreas de especial interesse para a conservação. As ações de conservação devem ser planejadas levando em consideração essa ameaça, a fim de reduzir seus impactos potenciais. Para isso, países como o Brasil devem reforçar sua vigilância sobre a expansão agrícola e a maneira como essa atividade é desenvolvida. Além disso, a integração internacional dos esforços de conservação deve ser buscada, dados seus benefícios para a biodiversidade e para a produção de alimentos. E por fim, a humanidade deve optar por formas de produção agrícola que reduzam seus impactos, inclusive evitando sua expansão futura, mas que possam satisfazer as necessidades da população humana globalmente.
369

A plant ecological study and management plan for Mogale's Gate Biodiversity Centre, Gauteng

Tuckett, Alistair Sean 12 1900 (has links)
The Mogale’s Gate Biodiversity Centre is a 3 060 ha reserve located within the Gauteng province. The area comprises grassland with woodland patches in valleys and lower-lying areas. To develop a scientifically based management plan a detailed vegetation study was undertaken to identify and describe the different ecosystems present. From a TWINSPAN classification twelve plant communities, which can be grouped into nine major communities, were identified. A classification and description of the plant communities, as well as, a management plan are presented. The area comprises 80% grassland and 20% woodland with 109 different plant families. The centre has a grazing capacity of 5.7 ha/LSU with a moderate to good veld condition. From the results of this study it is clear that the area makes a significant contribution towards carbon storage with a total of 0.520 tC/ha/yr stored in all the plant communities. / Environmental Sciences / M.Sc. (Environmental Management)
370

Disturbance, recovery and resilience in tropical forests : a focus on the coastal peat swamp forests of Malaysian Borneo

Cole, Lydia Eve Spencer January 2013 (has links)
Tropical forests have existed for up to one hundred million years, and today provide many ecosystem services vital for human well-being. They also harbour great biodiversity, which, in addition to its intrinsic value, plays a key role in the functioning of these ecosystems. Despite their local to global significance, there are still many knowledge gaps concerning the dynamic processes that govern the functioning of tropical forests. Rapid rates of deforestation and landscape conversion, predominantly for logging and industrial agriculture, are limiting the time and opportunity available to collect the information needed to fill these gaps. This research aims to shed light on the long-term ecological functioning of tropical forests, specifically investigating the history of disturbance in these ecosystems and the response of forest vegetation to past perturbations. The carbon-rich tropical peat swamp forests found along the coast of Sarawak, Malaysian Borneo, are a central focus of this study. For these forests in particular, a large deficit of knowledge surrounding their history and unique ecological functioning is coupled with some of the highest conversion rates of all tropical forest ecosystems across the world. In this thesis, palaeoecological data has been used to reconstruct temporal variability in forest vegetation coincident with external perturbations in order to identify changes in the resilience of these ecosystems through time, via indicators such as slowing rates of recovery and reduced regeneration of forest vegetation. Results suggest that tropical forest ecosystems have, for the most part, shown resilience to natural disturbances in the past, ranging from instantaneous localised tree-fall to longer-term regional climatic change; but that recent anthropogenic disturbances, of novel forms and greater intensities, are jeopardizing the potential for forest recovery and thus compromising ecosystem resilience. These findings enhance our understanding of the ecology of tropical peat swamp forests, and tropical forests more broadly. They also provide a context for contemporary tropical forest management, allowing for predictions on future responses to disturbance and enabling more ecologically sustainable landscape planning.

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