Shrub encroachment in a wooded-steppe mosaic: Combining gis methods with landscape historical analysis

Abstract

Shrub encroachment at the expense of grasslands is a world-wide phenomenon, which has considerable nature conservation consequences. On the southern slope of Mt Szársomlyó, one of Hungary's most unique nature reserves, shrubforest cover has been rapidly increasing in the past few decades. Our aim was to quantify this process and to give a comprehensive analysis of the landscape history of the area. Moreover, we compared Mt Szársomlyó to two nearby and similar mountains with a slightly different land-use history. It is almost certain that both shrubforests and grasslands were present on Mt Szársomlyó before human influence, although their original proportion is unknown. Southern slope was used as a pasture for centuries, maybe even for millennia. After grazing had come to an end during the 1970's, shrubforests began to expand rapidly: their cover increased from 9.83 % in 1964 to 21.7 % in 2005. In the case of the other two mountains, where grazing stopped earlier, forest cover is considerably higher than on Mt Szársomlyó, but this is partly due to the afforestation. It can be concluded that grazing of south-exposed rock swards should be regarded as a traditional land-use in the region. Further studies are needed to support nature conservation decisions. © 2013, ALÖKI Kft., Budapest, Hungary.