松嫩平原假苇拂子茅无性系种群的年龄结构

假苇拂子茅是典型的无性系禾草，分蘖节存活时间最多为４年，根茎存活的时间最多为３年；１龄级分蘖株生产力最高，１龄级 物质贮存能力最大，放牧场和割草场假苇拂子茅无性系种群的分蘖株均为增长型的年龄级蘖的物质生产；放牧扰动对假苇拂子茅无性系种群各龄级要茎的养分贮藏均有不利影响。割草场和放牧场假苇拂子茅潜在无性系种群均属于增长型的年龄结构。

Age structure of clone population of Calamagrostis pseudophragmites in songnen plain of China

Calamagrostis pseudophragmites is a species of typical clone grass. The oldest tiller nodes could live for four years, while the oldest rhizome for three years. Among the three age classes of the clone population the productivity of the 1 st class tillers and the capacity of storage of the 1 st class rhizomes were the largest. The age structure of tillers was of expanding type on both pastures for haymaking and that for grazing. Grazing could promote the development and survival of plants in the 2 nd and the 3 rd classes. The storage of nutrients in rhizomes was determined by the productivity of tillers in the same age class. Grazing would have negative effect on the storage of nutrients in rhizomes of all age classes. On both pastures for haymaking and that for grazing the age structure of potential clone population was of expanding type.