Effectiveness of Exclosures on Restoration of Degraded Alpine Meadow in the Eastern Tibetan Plateau

摘要

Restoration of degraded alpine meadow caused by overgrazing is directly related to land sustainable and economical development in the Tibetan Plateau. The objective of this study was to evaluate changes in vegetation and soil characteristics in areas under overgrazing and exclosed for 5 to 10 years for grazing in a degraded alpine meadow on the eastern Tibetan Plateau. Results showed that excluding livestock grazing resulted in significant increases in vegetation coverage and plant biomass by enhancing development of perennial grasses and sedges. Soil organic carbon and total nitrogen in the 0-10Â cm soil layer increased significantly with increasing exclosure time. Soil clay and water contents were higher in the exclosed sites than in the grazed site. The results suggested that the degraded alpine meadow due to overgrazing in this region can be reversed and significant increases in soil fertility, vegetation diversity, cover, and biomass can be achieved by implementing adequate protecting practices.