Recreational use impact on soil and vegetation at picnic sites in Aleppo pine forests onMount Carmel, Israel

Abstract

Natural Aleppo pine (Pinus halepensis Mill.) forests in Israel are scarce and their conservation value and interest lie in their species richness. The aim of this study was to describe the magnitude and the spatial variation of the impact of picnic sites on the vegetation and soil of natural Eastern Mediterranean Aleppo pine forests in the Mt. Carmel National Park, Israel. The resistance to recreational impacts was studied. Vegetation (total and relative cover, number of species, and composition) and soil characteristics (penetration depth, litter biomass, organic matter, soil moisture, aggregate stability, and distribution) were monitored at four picnic sites established 20 years ago. The impact on soil is expressed by an increase in compaction, a decrease in litter biomass, and in increase of spatial homogeneity of these two characteristics. The under story vegetation cover and its height are significantly lower at the picnic sites than at the periphery and in the adjacent undisturbed forest. Herbaceous species composition at the picnic sites differs from that at the periphery and in the adjacent undisturbed forest. The impacts on vegetation and soil at the picnic sites are highly localized. It is concluded that the picnic sites in the Aleppopine forests in Israel demonstrate a high resistance to trampling impacts. Their relatively high species richness and diversity, together with the high soil organic matter and aggregate stability found in the most heavily used areas, ensure high ecosystem rehabilitation of sites used for recreation.