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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.
21

Det svenska områdesskyddet : Ett samspel mellan diskurs och institutioner

Farzin, Maziar January 2010 (has links)
Sweden has had laws protecting nature for about a hundred years. In this paper the views of nature and the values that serve as a rationale for protective measures are analyzed as results of a social process characterized by the dialectic relationship between institutions and discourse. Critical discourse analysis (CDA) is used to study this relationship and the discursive practices used by institutions, which reproduce or reshape views of nature that define the relationship between society and nature. Institutional design contributes to shaping discourse in the field of nature protection, while being originally shaped by discourse. In Sweden, the national park is an institution that reproduces a view of nature as the wild and untamed opposite of society, and the natural reserves reproduce a view of nature as holder of a multi-faceted set of values intertwined with society. However, the most recently formed national park, the marine national park of the Koster sea includes resource values that threaten the hegemony of arcadian discourse within the institution and indicates social change.
22

Effekter av upphörd hävd i Lurö skärgård : Har diversiteten av kärlväxtarter förändrats? / Effects of abandoned management in the Lurö archipelago : Are there any changes in the diversity of plants?

Thor, Annelie January 2008 (has links)
One of the main reasons for the massive loss in plant species diversity is the fragmentation of habitats. In Europe, open pastures and meadows are the habitats going through the most changes during the 20th century, according to the agricultural changes. In this study vascular plants were invented at five different islands in the Lurö archipelago, Vänern, Sweden. The aim of the study was to sort out whether the diversity of plants has gone through any changes in abandoned managed grasslands compared to continuous managed grasslands. The aim was also to study if a change in the landscape has made any differences for the species development or decline. The results indicate that the number of vascular plants were significantly lower in the abandoned areas than the still managed areas. Results, only from the field layer, showed same results. There was a significant difference between the number of indicators in managed lands than lands that were abandoned for 30-40 and 100 years ago. A comparison from earlier study, from a time when grazing had just ceased at some islands, showed a significant difference in plant species diversity between the years. Just a few decades can impoverish a plant community that might have taken hundreds or even thousands of years to build up. To preserve the biological diversity formed by human impact, one must continue managing the lands. / En av de största orsakerna till den massiva förlusten av växtarter, är fragmenteringen av habitat. I Europa är öppna naturbetesmarker och ängar de habitat som genomgått de största förändringarna i och med jordbrukslandskapets omstruktureringar under 1900-talet. I den här studien inventerades kärlväxter på 5 olika öar i kulturlandskapet Lurö skärgårds naturreservat. Syftet var att ta reda på hur diversiteten bland kärlväxtarter skiljer sig mellan hävdade gräsmarker och f.d. gräsmarker där hävd upphört och hur ett förändrat landskap spelat roll för artantalets utveckling eller tillbakagång. Resultat visade att antalet kärlväxter var signifikant lägre i marker som slutat hävdas, än marker som fortfarande hävdas. Även jämförelser i enbart fältskiktet visade ett signifikant högre artantal hos välhävdade marker än marker där hävd upphört. Det fanns en signifikant skillnad mellan antalet indikatorarter i marker som var under hävd och marker som slutat hävdas för 30-40 år sedan, kontra 100 år sedan. Vid jämförelser med en tidigare studie, som ägt rum precis efter att hävden upphört på ett flertal lokaler visade resultat att det fanns en signifikant skillnad i artantal mellan de båda åren. På några få decennier kan ett helt växtsamhälle som byggts upp under hundratals eller kanske till och med tusentals år utarmas. För att bevara den biologiska mångfald som formas av en störningsregim beroende av människans inverkan, måste hävd fortsätta kontinuerligt.
23

Kommunalt naturskydd som en del av markanvändningsplaneringen : en fallstudie av olika synsätt i samband med upphävande av naturreservat

Bergkvist, Tomas January 2007 (has links)
In metropolitan areas where the exploitation pressure increases, also the importance to point out nature areas grows, both for the sake of outdoor life and for biodiversity conservation. Since nature conservancy and spatial planning constitute two different parts of the municipalities land use control, a case study has been carried out in two municipalities in the Stockholm region, Huddinge and Järfälla. Both these municipalities have protected about one third of their land and today there are plans to repeal parts of the reserves to enable exploitation. This thesis shows – from the theoretical concept of sustainable development – officials, politicians and non-governmental organizations perspectives on questions concerning land use together with the work with nature reserves and repeals. The study focuses on how different basic attitudes and paradigms emphasizes different aspects of sustainable development and how this in turn affects the work to repeal nature reserves. Interviews with stakeholders in the municipalities and documents concerning land use and nature reserves demonstrates that there is distinct differences between the planning-paradigm, based on spatial planning, and the environmental-paradigm, based on nature conservation. From the planning-paradigm it is considered that nature reserves had to big impact on the munici­pality's land use and that valuable nature more frequently should be protected by the Swedish planning and building act. From the environmental-paradigms view the nature conservancy is – and should also in the future be – an important tool in the long-term prevention to stop valuable nature from being exploited. The thesis also stresses the importance to in the work with repeals take all effects that this kind of decision can lead to into account – not just in the repealed area but also for the future work with nature reserves on the whole. / I storstadsregioner där exploateringstrycket blir allt större, ökar också vikten av att peka ut naturområden, både för det rörliga friluftslivet samt för bevarande av den biologiska mångfalden. Utifrån det att naturskydd samt fysisk planering utgör varsin del av kommuners styrning av mark­användningen har en fallstudie genomförts i två kommuner i Stockholmsregionen, Huddinge och Järfälla. Båda dessa kommuner har skyddat ungefär en tredjedel av kommunens mark och idag finns planer på att upphäva delar av reservaten för att där möjliggöra exploatering. Uppsatsen visar – utifrån det teoretiska begreppet hållbar utveckling – hur tjänstemän, politiker och intresse­organisationer ser på markanvändningsfrågor samt arbetet med naturreservat och upphävande. Studien fokuserar på hur olika grundinställningar och paradigm lyfter fram olika aspekter av hållbar utveckling samt hur detta i sin tur påverkar arbetet med att upphäva naturreservat. Intervjuer med kommunala aktörer samt dokument rörande markanvändning och naturreservat visar att det finns tydliga skillnader mellan planparadigmet, med grund i den fysiska planeringen, och miljö­paradigmet, med grund i naturvården. Utifrån planparadigmet anser man att naturreservaten har fått för stor inverkan på kommunens markanvändning och att värdefull natur oftare borde skyddas med hjälp av plan- och bygglagens verktyg. Från miljöparadigmets vinkel är naturskyddet – och bör även i fortsättningen vara – ett viktigt verktyg för att långsiktigt förhindra att värdefull natur exploateras. Uppsatsen framhåller också vikten av att man vid upphävande av naturreservat tar hänsyn till alla effekter som ett sådant beslut kan leda till – inte bara i det upphävda området utan även för det fortsatta arbetet med naturreservat i stort.
24

Socio-economic impact of Prunus africana management in the Mount Cameroon region : A case study of the Bokwoango community

Ekane, Bellewang Nelson January 2006 (has links)
<p>In most developing countries, forest resources are a major source of livelihood for forest dwellers. Forests provide fuel wood, farm products, meat, timber and plants of high medicinal value, including Prunus africana. The collection of medicinal plants is also an important source of cash income for some forest communities, and widely relied on to cure illnesses (Poffenberger, 1993). Because of this, the poor forest dwellers in particular are forced to exert pressure on their surrounding environment to make ends meet. Indiscriminate exploitation of forest resources has cost some forest dwellers dearly as they are now experiencing marked reduction of wildlife, forest cover, soil fertility and most importantly water supply, which is a key to life. Prunus africana has a very high economic and medicinal value locally as well as internationally. The exploitation of this species is a very profitable activity in most parts of Africa where it occurs, including the Mount Cameroon region. In recent years, most youths and young men in the Mount Cameroon region have seemingly become less interested in their usual income generating activities (farming, hunting, etc.) because of reduced productivity and have taken up Prunus harvesting as their major source of income. Increase in demand for this species by the French pharmaceutical company (Plantecam), weak institutional capacity to control exploitation, uncontrolled access into the forest, scramble for diminished stock by legal and illegal exploiters, destruction of wild stock by unsustainable practices, and insufficient regeneration of the species in the past have almost driven this species to extinction in certain parts of Cameroon and made it severely threatened in others. Prunus africana is presently threatened with extinction in the entire Mount Cameroon region. In response to this, the Mount Cameroon Project (MCP) and the Ministry of Environment and Forests (MINEF) helped some communities (Bokwoango and Mapanja) in the Mount Cameroon region to form Prunus africana harvesters’ unions with the aim of preserving the resource and improving the socio-economic benefits. The principal aim of the Bokwoango Prunus africana harvesters’ union is to ensure sustainable exploitation of Prunus africana while saving money for important development projects for individual members, their families and the entire community. This piece of work highlights the different facets of Prunus africana management in Cameroon in general and the Bokwoango community in particular. The study examines the socio-economic impact of Prunus africana management in the Bokwoango community and shows specifically the management role played by the Bokwoango Prunus africana harvesters’ union to reduce the rate of exploitation of Prunus africana and also to ensure benefit sharing of the earnings from sales of Prunus bark. It at the same time brings out the constraints encountered by harvesters as well as the opportunities that can make the union become more viable to the socio-economic development of the Bokwoango community. Results of this study show that for the short period that the Bokwoango Prunus africana harvesters’ union has existed, the socio-economic changes in this community are encouraging if one compares the present situation with that before the formation of the union. Most importantly, there has been increased awareness on the great need to conserve not only the threatened Prunus africana species but also other threatened plant and animal species in the region through sustainable hunting, harvesting and regeneration. Some proposals are made for efficient natural resource management and improvements on livelihood through alternative income generating activities. The study ends with recommendations for policy and institutional reforms as well as suggestions for further research in sustainable management of Prunus africana.</p>
25

DETERMINATION OF FREE STAND-ALONE PHOTOVOLTAIC POTENTIAL IN GERMANY BY GIS-BASED SITE RANKING

Shoshtari, Salahaldin January 2010 (has links)
The purpose of this study is to find potential areas suitable for energy production using renewable sources. For this aim, accurate assessments are necessary. The assessments include geographical suitability, closeness of infrastructure and observing local and regional framework concerning the use of renewable sources together with environmental protection. In addition, economical factor is considered in such an assessment. In this study, the Photovoltaic (PV) production potential for Germany is considered. An accurate and complete data set is necessary in order to achieve reliable results. In addition, a powerful database management and strong analysis tools are required. Geographical Information System (GIS) is a tool for finding suitable sites for the photovoltaic production.Using GIS, energy generation planners are able to visualize solar densities throughout the considered area. In addition, they can find the optimal and most economical sites by the combination of solar potential with the information about land. In this study, data sources consist of meteorological and geographical conditions. Furthermore, all analyses have been performed using Arc GIS Desktop. This study demonstrates the possible places for photovoltaic plants and indicates suitable candidates according to weights and factors in multi criteria analysis. The solar radiation data is from year 1995 to 2005. Land cover data is according to Corine 2000 and the more detailed Raumordnungskataster (Rok) for Weser-Ems. Numerical results are reliable from a comparison point of view. This study demonstrates the sensitivity of the defined criteria with respect to electricity production. In particular, this study is useful to see the capabilities of GIS for site selection regarding photovoltaic plants.The purpose of this study is to find potential areas suitable for energy production using renewable sources. For this aim, accurate assessments are necessary. The assessments include geographical suitability, closeness of infrastructure and observing local and regional framework concerning the use of renewable sources together with environmental protection. In addition, economical factor is considered in such an assessment. In this study, the Photovoltaic (PV) production potential for Germany is considered. An accurate and complete data set is necessary in order to achieve reliable results. In addition, a powerful database management and strong analysis tools are required. Geographical Information System (GIS) is a tool for finding suitable sites for the photovoltaic production.Using GIS, energy generation planners are able to visualize solar densities throughout the considered area. In addition, they can find the optimal and most economical sites by the combination of solar potential with the information about land. In this study, data sources consist of meteorological and geographical conditions. Furthermore, all analyses have been performed using Arc GIS Desktop. This study demonstrates the possible places for photovoltaic plants and indicates suitable candidates according to weights and factors in multi criteria analysis. The solar radiation data is from year 1995 to 2005. Land cover data is according to Corine 2000 and the more detailed Raumordnungskataster (Rok) for Weser-Ems. Numerical results are reliable from a comparison point of view. This study demonstrates the sensitivity of the defined criteria with respect to electricity production. In particular, this study is useful to see the capabilities of GIS for site selection regarding photovoltaic plants.
26

Network Based Tools and Indicators for Landscape Ecological Assessments, Planning, and Design

Zetterberg, Andreas January 2009 (has links)
<p>Land use change constitutes a primary driving force in shaping social-ecological systems world wide, and its effects reach far beyond the directly impacted areas. Graph based landscape ecological tools have become established as a promising way to efficiently explore and analyze the complex, spatial systems dynamics of ecological networks in physical landscapes. However, little attention has been paid to making these approaches operational within ecological assessments, physical planning, and design. This thesis presents a network based, landscape-ecological tool that can be implemented for effective use by practitioners within physical planning and design, and ecological assessments related to these activities. The tool is based on an ecological profile system, a common generalized network model of the ecological infrastructure, graph theoretic metrics, and a spatially explicit, geographically defined representation, deployable in a GIS. Graph theoretic metrics and analysis techniques are able to capture the spatio-temporal dynamics of complex systems, and the generalized network model places the graph theoretic toolbox in a geographically defined landscape. This provides completely new insights for physical planning, and environmental assessment activities. The design of the model is based on the experience gained through seven real-world cases, commissioned by different governmental organizations within Stockholm County. A participatory approach was used in these case studies, involving stakeholders of different backgrounds, in which the tool proved to be flexible and effective in the communication and negotiation of indicators, targets, and impacts. In addition to successful impact predictions for alternative planning scenarios, the tool was able to highlight critical ecological structures within the landscape, both from a system-centric, and a site-centric perspective. In already being deployed and used in planning, assessments, inventories, and monitoring by several of the involved organizations, the tool has proved to effectively meet some of the challenges of application in a multidisciplinary landscape.</p>

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