青藏高原东北边缘地区高寒草甸群落特征对封育的响应

封育是退牧还草恢复退化草地的主要措施,而封育的时效限制着该措施的实施年限。本研究连续6年监测了青藏高原东北边缘天祝县高寒草甸群落特征对封育的响应。结果表明,高寒草甸群落盖度、高度、物种多样性及生物量均随着封育年限增加表现为先显著降低,后显著升高,再显著降低(P<0.05),第4年时群落高度和盖度最高,物种多样性和生物量最大,说明高寒草甸适宜封育时间是4年。

Influence of enclosure on community characteristics of alpine meadow in the northeastern edge region of the Qinghai-Tibetan Plateau

Enclosures are one of the measures to restore degraded grassland by turning grazing grasslands into protected grasslands but the period of fencing is the key to influencing the plant community.A six year field experiment was conducted to determine the responses of community features of alpine meadow to enclosure at Tianzhu Autonomous County on the northeastern edge of the Qinghai-Tibetan Plateau.The cover,height,species diversity and biomass of the alpine meadow first increased,then decreased,and finally decreased again as the enclosure was prolonged,peaking at the fourth year.These results suggest that a 4-year enclosure is suitable for alpine meadows in the study region.