The thesis discusses conservation of natural vegetation in agricultural landscapes which is under strong pressure from intensive agriculture and the spread of urbanization. With spatial analysis of forest patches and trees outside the forest we have got an insight into the current state of natural vegetation. Then, using methods derived from graph theory we examined connectivity between forest patches. The nodes of the graph represent forest patches, links between them least-cost paths, which were calculated on the basis of cost surface containing resistance value of each land use. The contribution of each forest patch to overall habitat connectivity and accessibility was than calculated using selected indicators. Based on indicators we identified, for selected dispersal distance values, the most important connecting patches that contribute most to maintain the connectivity between forest patches. We found that the largest forest patches represent the backbone for connectivity, complemented by smaller patches that cover other strategic points for connectivity. The biggest limitations for connectivity represented areas with the highest costs. On the basis of selected methods we did not find any major impact on connectivity for trees outside the forest, nevertheless they have proved to be an important element to prevent the occurrence of areas without natural vegetations, despite their modest size they occupied. We created a map with a network of the most important forest patches, that act as connecting patches, and other forest patches that preserve landscape heterogeneity. Finally we have given guidelines for directing and mitigating the effects of further reducing of natural vegetation remains.
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