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在退化羊草草原上耕翻播种羊草（Ｌｅｙｍｕｓｃｈｉｎｅｎｓｉｓ）后，植物群落演替动态与群落特征变化规律的研究结果进行了报导．通过对１９８４～１９９５年野外实地观测所得数据进行分析，结果如下：羊草人工草地经过１３年的演替群落丰富度（ｒｉｃｈ－ｎｅｓｓ）有所增加，种类组成出现差异．群落密度和地上生物量都为中期较高的峰型变化规律．群落的多样性指数和均匀性指数在后期有明显增加．羊草的重要值为前期迅速增加，中期相对稳定和后期下降的变化规律．１３年的演替过程可划分为三个阶段：前３年（１９８３～１９８５）为羊草种群的增长阶段，群落组成为羊草十一、二年生杂类草群落；随后５年羊草种群处于绝对优势且相对稳定的地位，群落组成为羊草＋冰草（Ａｇｒｏｐｙｒｏｎｍｉｃｈｎｏｉ）＋多年生杂类草群落，此阶段也是羊草草地的最佳阶段；第三个阶段为后５年（１９９１～１９９５）此阶段羊草在群落中的作用减弱，多年生植物种类和数量有所增加，群落组成为羊草＋冰草、变蒿（Ａｒｔｅｍｉｓｉａｃｏｍｍｕｔａｔａ）、阿尔泰狗娃花（Ｈｅｔｅｒｏｐａｐｕｓａｌｔａｉｃｕｓ）＋丛生小禾草群落．羊草人工草地正向天然羊草草原群落演变，演替过程将继续进行
The results of researches on the changes of plant community succession and community characteristics after sowing Leymus chinensis in the degraded Leymus chinensis steppe were reported. The results obtained from field observations in 1984-1995 were as follows: The rich-ness of the succession population of Leymus chinensis grassland increased after 13 years and the species composition was different. Community density and aboveground biomass were both higher peak-type changes in the middle period. The community diversity index and evenness index increased significantly in the later period. Leymus important value for the rapid increase in the early, mid-term relative stability and decline in the late changes. The 13 years of succession process can be divided into three stages: the first three years (1983 ~ 1985) for the growth stage of the population of Leymus chinensis, the community composition of Leymus chinensis eleven, two-year-old hybrid grass community; Absolute and relatively stable position, the community composition of the grass + Agropyron michnoi + perennial miscellaneous grass community, this stage is also the best stage of Leymus chinensis grassland; the third stage for the next 5 years (1991 ~ 1995) At this stage, the role of Leymus chinensis in the community weakened, and the species and number of perennial plants increased. The community composition was Leymus chinensis + Artemisia annatum, Heteropapusaltaicus + Cong grassland community. Leymus chinensis artificial grassland is evolving towards natural Leymus chinensis steppe community, the succession process will continue