中文摘要：

2010年天祝县天然草地退化面积为23．00万hm^2，占草地面积的58．76％，目前仍以每年1．33万hm^2的速度退化。草地退化是自然因素和人为因素共同作用的结果。但超载过牧是主要原因，它引起天然草地由轻度退化向中度和重度退化演变。因此，本研究以控制栽畜量、解决草畜矛盾为核心措施，提出天然草地综合治理对策，以促进天祝县天然草地走上可持续发展的道路，为祁连山草地资源合理利用和草地退化防治提供技术参考。

英文摘要：

230 000 ha grassland accounted for 58.76%of the total grassland area have degraded at Tianzhu County in 2010. At present, the county＇s natural grassland is still degrading by a rate of 13 300 ha per year. The grassland degradation was caused by both natural factors and human activities. However, over- grazing was a main reason for natural grassland degradation from light to heavy. Therefore, comprehen sive countermeasures based on controlling grazing capacity and resolving conflicts between grass and live- stock were put forward for natural grassland in the paper, which can help sustainable development of Tianzhu natural grassland and offer technical references for areas of Qilian Mountains on rational utilization of grassland resources and control of degradation.