The dissertation focuses on the influence of landscape matrix heterogeneity on: (a) model suitability of black grouse habitat and dispersion characteristics of the habitat patches in the mid-altitude and mountain landscape of the North-Eastern Slovenia at the altitude of over 1000 m above the sea level, with the total area of 42.071 hectares in the period between 1824/27 up to present, (b) presence and spatial distribution of the key variables in the wider display habitat of black grouse in 2006/07 in five areas. Habitat suitability was analysed in the area of 249 hectares, comprising 3979, 25 m2 plots, at seven active leks of black grouse. Status anddynamics of land use changes in five areas in the periods 1824/27, 1900, 1937, and 2005 was studied with the GIS spatial analysis. The key findings andconclusions are: 1) The process of forestation within the cadastral municipalities took place throughout the studied time series. Temporally certain shifts towards more equalised/similar ratios in land use are noticeable to the areas at lower altitude and of smaller size than the areas which are limited by substantial mid-altitudes and mountain ranges, where nowadays forest is the prevalent landscape feature. 2) In the 1824/27 period 76,3 % of the studied area was covered by forests, 16,1 % was covered by pastures, 2,9 % by grassland, 2,7 % of the area was represented by arable land, 1,6 % was barren land, and 0,4 % other land use. The largest proportion of non-forest land, mostly pastures, was found in the eastern Karawanken and Savinja Alps (KSAK) - 28,4 %, while elsewhere it amounted to significantly less. The share of grassland increases with the altitude, but the trend is cyclical. 3) The forest category represented/covered more than half (57 %) of the area in all the four time periods. The lowest share was measured in the regions of Pohorje (69 %) and KSAK (45 %), as a consequence of clearcutting management. Between 1937 and 2005 forestation process was the most extensive in the area of KSAK with 19,9 % of the total area being forested, and in the Pohorje area (14,5 %). 4) The number of non-forest patches indicated constant growth throughout the total studied period of 180 years; at the same time the non-forest surface was more fragmented and decreased in size. 5) The size of suitable model habitat of black grouse changed in relation with forestation and deforestation of the area. The suitable areas are those of KSAK, Pohorje and Kobansko hilltops, by their size and time especially KSAK in Pohorje between 1900 and 1937. By 2005, the Pohorje model habitat was reduced for 46 %, while the KSAK area habitat decreased for 21 %. The model habitat patches within the area, considering the fact that the maximum distance which still allows optimum migration of the species is 6000 m, were well connected in all of the four observed time series. 6) Distribution and abundance of dietary important herbal species in the wider lek areas are affected by the spatial structure, especially by the vegetation types. Abundance of bilberry, as the most important species for the non-winter diet of black grouse, is the higheston the overgrowing grasslands and grasslands, whereas it is the lowest in forests - similar is true for the majority of dietary important species. The central part of leks is significantly different from the wider surroundingarea. 7) The wider area of black grouse leks are not homogenous units; there are differences between the display grounds structure in silicateareas and those in calcite areas.
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