Impact of Transhumant Livestock Grazing Abandonment on Pseudo-Alpine Grasslands in Greece in the Context of Climatic Change

Pseudo-alpine grassland ecosystems have started to decline during the past few decades. According to many studies, climate change and abandonment of traditional anthropogenic activities are directly linked to this phenomenon. However, the interaction of these two factors with pseudo-alpine grasslands has not been studied in Greece. The aim of this study was to assess the impact of climatic change and abandonment of transhumant livestock grazing on pseudo-alpine grassland ecosystems structure and stability in Mt Vermio and Mt Zireia. Geographic Information System data on land use/land cover from 1945 and 2020, as well as climatological and livestock data, have been examined and presented. Landscape metrics were also used to quantify landscape structure changes. Although both mountains’ pseudo-alpine grasslands have reduced in size, Mt Zireia has experienced an upward treeline shift, which seems to be the result of climate change, while in Mt Vermio, the more severe transhumance abandonment caused horizontal tree expansion. There are strong indications that a rise in temperature is the main driver for the upward increase in treeline