Investigation of Exclosure effects in composition & density of vegetation and soil conditions in forest region Baft-Kerman

Arid & semi arid forests are complicated ecosystems which play an integral part by not only protecting soil and water and sequestrating carbon but also by producing byproducts and economically supporting the life of most inhabitants. Regrettably, the excessive and inefficient exploitation of such valuable resources namely by overgrazing, cutting top branches of trees, developing new dry farming places and cutting down trees for fuelwood have inflicted irreversible damage upon the vegetation cover and soil.Thus, exclosure is considered as one of the effective methods for improving the damaged plants. The current study aims to investigate the effects of the 15- year exclosure on the changes in the vegetation cover for Amygdalus forests studied in Sechah - Baft region. Here, the random systematic sampling method was applied ( the mesh with the dimensions 100m2 *100m2 ); for this reason, 50 plat (with the dimensions 20m2 *20 m2 ) for tree cover & 50 plat(with the dimensions 10m2 *10 m2 ) for understory cover in the exclosure area & the same numbers of plats with the above-mentioned specifications have been pitched in the nearby field. In the present study, the SPSS, which is a statistical software, has been used to compare the means. Similarly, in order to investigate the physical and chemical condition of the soil, some samples of the region under study (in exclosure & nearby) were selected so that characteristics of the soil, namely, structure, acidity, electric conductivity, organic substance, lime, plaster, potassium, sodium, calcium, sulfate & bicarbonate can be measured. Findings suggest that canopy covers of species, density and diversity of species (forest & understory) in the exclosure is more than those outside the exclosure. Also, the organic substance percentage and soil depth in exclosure- mananged region are more desirable, and the physical characteristics of soil have a significant impact on the changes in the vegetation cover of the region. (The fact that the soil nearby the exclosure was beaten due to cattle grazing made it difficult for seeds to be germinated). It is also worth noting that the exclosure led to an increase in the number of herbaceous species & A.scoparia in the region and as a result it can be considered as a leading method pioneered for pitching of vegetation.