Volume XI |

Trends in land cover change in abandoned mountain pastures. A case study: Măgura Marga Massif (the Southern Carpathians)

Abstract: Grazing was the main activity of the inhabitants of the region, so that on an area of only 750 hectares, 16 sheepfolds existed simultaneously. In the last 20 years, mountain pastures were gradually abandoned a fact which led to some changes in land cover, mainly close to timberline. The aim of this paper is to identify general trend of land cover change using change – detection methods based on Landsat TM imagery for 1988 – 2011 time interval. Detailed analysis based on field research and high resolution air photos was also made for the areas with highest land cover changes. The analysis of the historical maps allowed a better understanding of the land cover transformations in the last 70 years. The results showed that the general trend in pastures area for the last 23 years is the biomass gain. Even if this phenomenon has a low and medium magnitude, it is a dominant one, appearing on more than 88% of the pastures area. Moderate intensity changes are explained due to the relatively short time interval since pastures were abandoned. Major changes occurred in some areas: on the southern slopes, because of the specific topoclimate, in areas where the anthropogenic timberline was lowered at very low altitudes and in the areas near the spruce timberline. There are also areas where there are no obvious changes of the timberline. These occur more frequently on the northern and western slopes, near the beech forest timberline. In the study area, the timberline is still anthropogenic, but if the current trend of forest regeneration continues, the timberline will change to a climatic one.