中文摘要：

研究对象为内蒙古赤峰市克什克腾旗达里诺尔自然保护区境内的羊草草原，以植物群落为特征，应用逐步聚类分析方法定量划分出了不同退化程度的草地，并且对区分不同退化程度的草地植被指标选择做了初步的尝试，为牧民合理利用当地家庭牧场提供决策依据。聚类结果为从对照区（冬季打草场）出发到居民点附近存在三段不同退化程度的草地，依次为0～1700m、1700～2700m和2700～4100m范围内的区域；通过测定生长盛期主要伴生植物种糙隐子草、星毛委陵菜及群落建群种羊草的地上现存量这3项敏感的植被指标，可以实现羊草草原退化程度的定量判定。

英文摘要：

An experiment was carried out on a Leymus chinensis steppe in the Keshiketeng Banner of Chifeng, Inner Mongolia, in a research site located east of the Dalinuoer natural reserve area. The steppe was classified quantitatively according to the different degrees of degradation and the plant community characteristics, based on the quantitative indicators primarily suggested for identifying the grassland degradation degree, and for the local herders to use their family grazing land more reasonably. The experimental results show that by the distinct degree of degradation the semiarid grassland can be classified into three zones： they were within 0～1700 m,1700～2700 m, and 2700～4100 m between the hay cutting pasture and the residential area. The standing crops of Cleistogenes squarosa, Patentilla acaulis, and L. chinensis during their flourishing growth period were the most sensitive indications for an easy judgment of the degree of grassland degradation on the L. chinensis steppe.