7 resultados para Semi-transparent

em Helda - Digital Repository of University of Helsinki


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This study Contested Lands: Land disputes in semi-arid parts of northern Tanzania. Case Studies of the Loliondo and Sale Division in the Ngorongoro District concentrates on describing the specific land disputes which took place in the 1990s in the Loliondo and Sale Divisions of the Ngorongoro District in northern Tanzania. The study shows the territorial and historical transformation of territories and property and their relation to the land disputes of the 1990s'. It was assumed that land disputes have been firstly linked to changing spatiality due to the zoning policies of the State territoriality and, secondly, they can be related to the State control of property where the ownership of land property has been redefined through statutory laws. In the analysis of the land disputes issues such as use of territoriality, boundary construction and property claims, in geographical space, are highlighted. Generally, from the 1980s onwards, increases in human population within both Divisions have put pressure on land/resources. This has led to the increased control of land/resource, to the construction of boundaries and finally to formalized land rights on village lands of the Loliondo Division. The land disputes have thus been linked to the use of legal power and to the re-creation of the boundary (informal or formal) either by the Maasai or the Sonjo on the Loliondo and Sale village lands. In Loliondo Division land disputes have been resource-based and related to multiple allocations of land or game resource concessions. Land disputes became clearly political and legal struggles with an ecological reference.Land disputes were stimulated when the common land/resource rights on village lands of the Maasai pastoralists became regulated and insecure. The analysis of past land disputes showed that space-place tensions on village lands can be presented as a platform on which spatial and property issues with complex power relations have been debated. The reduction of future land disputes will succeed only when/if local property rights to land and resources are acknowledged, especially in rural lands of the Tanzanian State.

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Semi-natural grasslands are the most important agricultural areas for biodiversity. The present study investigates the effects of traditional livestock grazing and mowing on plant species richness, the main emphasis being on cattle grazing in mesic semi-natural grasslands. The two reviews provide a thorough assessment of the multifaceted impacts and importance of grazing and mowing management to plant species richness. It is emphasized that livestock grazing and mowing have partially compensated the suppression of major natural disturbances by humans and mitigated the negative effects of eutrophication. This hypothesis has important consequences for nature conservation: A large proportion of European species originally adapted to natural disturbances may be at present dependent on livestock grazing and / or mowing. Furthermore, grazing and mowing are key management methods to mitigate effects of nutrient-enrichment. The species composition and richness in old (continuously grazed), new (grazing restarting 3-8 years ago) and abandoned (over 10 years) pastures differed consistently across a range of spatial scales, and was intermediate in new pastures compared to old and abandoned pastures. In mesic grasslands most plant species were shown to benefit from cattle grazing. Indicator species of biologically valuable grasslands and rare species were more abundant in grazed than in abandoned grasslands. Steep S-SW-facing slopes are the most suitable sites for many grassland plants and should be prioritized in grassland restoration. The proportion of species trait groups benefiting from grazing was higher in mesic semi-natural grasslands than in dry and wet grasslands. Consequently, species trait responses to grazing and the effectiveness of the natural factors limiting plant growth may be intimately linked High plant species richness of traditionally mowed and grazed areas is explained by numerous factors which operate on different spatial scales. Particularly important for maintaining large scale plant species richness are evolutionary and mitigation factors. Grazing and mowing cause a shift towards the conditions that have occurred during the evolutionary history of European plant species by modifying key ecological factors (nutrients, pH and light). The results of this Dissertation suggest that restoration of semi-natural grasslands by private farmers is potentially a useful method to manage biodiversity in the agricultural landscape. However, the quality of management is commonly improper, particularly due to financial constraints. For enhanced success of restoration, management regulations in the agri-environment scheme need to be defined more explicitly and the scheme should be revised to encourage management of biodiversity.

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This work focuses on the factors affecting species richness, abundance and species composition of butterflies and moths in Finnish semi-natural grasslands, with a special interest in the effects of grazing management. In addition, an aim was set at evaluating the effectiveness of the support for livestock grazing in semi-natural grasslands, which is included in the Finnish agri-environment scheme. In the first field study, butterfly and moth communities in resumed semi-natural pastures were com-pared to old, annually grazed and abandoned previous pastures. Butterfly and moth species compo-sition in restored pastures resembled the compositions observed in old pastures after circa five years of resumed cattle grazing, but diversity of butterflies and moths in resumed pastures remained at a lower level compared with old pastures. None of the butterfly and moth species typical of old pas-tures had become more abundant in restored pastures compared with abandoned pastures. There-fore, it appears that restoration of butterfly and moth communities inhabiting semi-natural grass-lands requires a longer time that was available for monitoring in this study. In the second study, it was shown that local habitat quality has the largest impact on the occurrence and abundance of butterflies and moths compared to the effects of grassland patch area and connec-tivity of the regional grassland network. This emphasizes the importance of current and historical management of semi-natural grasslands on butterfly and moth communities. A positive effect of habitat connectivity was observed on total abundance of the declining butterflies and moths, sug-gesting that these species have strongest populations in well-connected habitat networks. Highest species richness and peak abundance of most individual species of butterflies and moths were generally observed in taller grassland vegetation compared with vascular plants, suggesting a preference towards less intensive management in insects. These differences between plants and their insect herbivores may be understood in the light of both (1) the higher structural diversity of tall vegetation and (2) weaker tolerance of disturbances by herbivorous insects due to their higher trophic level compared to plants. The ecological requirements of all species and species groups inhabiting semi-natural grasslands are probably never met at single restricted sites. Therefore, regional implementation of management to create differently managed areas is imperative for the conservation of different species and species groups dependent on semi-natural grasslands. With limited resources it might be reasonable to focus much of the management efforts in the densest networks of suitable habitat to minimise the risk of extinction of the declining species.

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In this thesis a manifold learning method is applied to the problem of WLAN positioning and automatic radio map creation. Due to the nature of WLAN signal strength measurements, a signal map created from raw measurements results in non-linear distance relations between measurement points. These signal strength vectors reside in a high-dimensioned coordinate system. With the help of the so called Isomap-algorithm the dimensionality of this map can be reduced, and thus more easily processed. By embedding position-labeled strategic key points, we can automatically adjust the mapping to match the surveyed environment. The environment is thus learned in a semi-supervised way; gathering training points and embedding them in a two-dimensional manifold gives us a rough mapping of the measured environment. After a calibration phase, where the labeled key points in the training data are used to associate coordinates in the manifold representation with geographical locations, we can perform positioning using the adjusted map. This can be achieved through a traditional supervised learning process, which in our case is a simple nearest neighbors matching of a sampled signal strength vector. We deployed this system in two locations in the Kumpula campus in Helsinki, Finland. Results indicate that positioning based on the learned radio map can achieve good accuracy, especially in hallways or other areas in the environment where the WLAN signal is constrained by obstacles such as walls.

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Corporate Social Responsibility (CSR) has become increasingly important topic in forest industries, and other global companies, in recent years. Globalisation, faster information delivery and demand for sustainable development have set new challenges for global companies in their business operations. Also the importance of stakeholder relations, and pressure to become more transparent has increased in the forest industries. Three dimensions of corporate responsibility economic, environmental and social, are often included in the concept of CSR. Global companies mostly claim that these dimensions are equally important. This study analyses CSR in forest industry and has focus on reporting and implementation of social responsibility in three international companies. These case-companies are Stora Enso, SCA and Sappi, and they have different geographical base, product portfolios and therefore present interesting differences about forest industry strategy and CSR. Global Reporting Initiative (GRI) has created the most known and used reporting framework in CSR reporting. GRI Guidelines have made CSR reporting a uniform function, which can also be measured between companies and different sectors. GRI Guidelines have also made it possible to record and control CSR data in the companies. In recent years the use of GRI Guidelines has increased substantially. Typically CSR reporting on economic and environmental responsibility have been systematic in the global companies and often driven by legistlation and other regulations. However the social responsibility has been less regulated and more difficult to compare. Therefore it has previously been often less focused in the CSR reporting of the global companies. The implementation and use of GRI Guidelines have also increased dialogue on social responsibility issues and stakeholder management in global companies. This study analyses the use of GRI´s framework in the forest industry companies´ CSR reporting. This is a qualitative study and the disclosure of data is empricially analysed using content analysis. Content analysis has been selected as a method for this study because it makes it possible to use different sources of information. The data of this study consists of existing academic literature of CSR, sustainability reports of thecase-companies during 2005-2009, and the semi-structured interviews with company representatives. Different sources provide the possibility to look at specific subject from more than one viewpoint. The results of the study show that all case-companies have relatively common themes in their CSR disclosure, and the differences rise mainly from their product-portfolios, and geographic base. Social impacts to local communities, in the CSR of the companies, were mainly dominated by issues concerning creating wealth to the society and impacting communities through creation of work. The comparability of the CSR reporting, and especially social indicators increased significally from 2007 onwards in all case-companies. Even though the companies claim that three dimensions of CSR economic, environmental and social are equally important economic issues and profit improvement still seem to drive most of the operations in the global companies. Many issues that are covered by laws and regulations are still essentially presented as social responsibility in CSR. However often the unwelcome issues in companies like closing operations are covered just briefly, and without adequate explanation. To make social responsibility equally important in the CSR it would demand more emphasis from all the case-companies. A lot of emphasis should be put especially on the detail and extensiveness of the social reponsibility content in the CSR.

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Many Finnish municipalities need to control their growth. In this research growth is understood as developments of land utilisation and also as a wide range of other changes that have mainly ap-peared as a result of a long term growth in population. The development growth control contains four areas: 1. adequate productivity of town planning, 2. stationing the growth to needs led and for sustainable developments, 3. quality of the developing environment, and 4. producing growth with communicative and transparent process. The aim of the research is to represent connection between town planning and development growth control. Research defines the role of town planning in the municipalities development growth control. In addition research focuses on links between town planning and development growth control in history, present and in the development work for the future. According to the hypothesis the extensive examination of town planning enables better growth control and promotes appropriate response to municipal changes regarding housing delivery. As an example there are five outskirt municipalities in the Helsinki region. They are called Kirkkonummi, Vihti, Nurmijärvi, Tuusula and Sipoo. The decision was to use examples based on a contingence theory. According to the theory there is no one correct way to operate. Therefore development should be based on individual municipal needs. In the research, municipality s needs were collected by 20 semi- structured interviews from municipal officials. In addition there were group interviews in Uusimaa Regional Council and in Uusimaa Regional Environmental Centre. There was also secondary material collected from official papers and statistics. Operationalisation was the analysis tool between empiric and literature reviews. The role of town planning has evolved during the 20th century from a more simple town plan level to operative stage in town planning hierarchy. Outskirt municipalities town planning was established during the 1960s. Since then one of the most important aims in the town planning has been to produce growth and building possibilities. Currently the challenge is to reach the satisfying rate of productivity and to meet increased housing demand. Other challenges include locating the appropriate geographical areas for growth; and the balance between required developments and planning permission decisions. Findings concluded that town planning should be more viable and it should have better ability to co-operate and operate in the changing operational environment. Municipality s ability to receive growth can increase and growth control can advance by planned and workable town planning. It is essential to take wide perspective of the each municipality's unique needs to improve productivity rather than to focus simply on productivity.