新疆霍城假苇拂子茅种群构件的年龄结构

通过生长季末期单位面积取样的方法，对新疆霍城县沟谷中不同生境的假苇拂子茅(Calamagrostis pseudophragmits)种群构件的组成及其年龄结构进行了研究。结果表明，3个生境的假苇拂子茅分蘖节的存活年限最长为6 a，分蘖株在数量上均由5个龄级组成，属稳定型年龄结构。就单株生产力的整体水平而言，3个生境的生产力水平表现为生境H2>生境H3>生境H1，且各生境间存在显著差异(P<0.05)，反映了单株生产力在不同生境间具有一定的差异。根茎的存活年限最长为5 a，根茎的生产力则以1 a或2 a龄级最高，各生境根茎长与根茎生物量均以1 a或2 a龄级所占比例最高，且随龄级的增加而递减，反映出潮湿、疏松的沙质土壤有利于假苇拂子茅根茎的生长和物质储存。

Age structure of modules on Calamagrostis pseudophragmits population in Huocheng County

Calamagrostis pseudophragmits is a perennial, rhizomatic and typical clone grass. Components and age structure of modules of C.pseudophragmites populations were studied at the end of growth season in different habitats in the Gully Mountains in Huocheng County of Xinjiang, China. It was found that the tiller nodes of C.pseudophragmits in three habitats kept alive as long as for 6 year, and there were five age classes of tillers which showed a stable age structure. Viewing the general conclusions as a whole, the productivity of per tillers in the second habitat (H2) was significantly higher than those of the third habitat (H3), the least was 2nd (H1), and there were significant difference among different habitats which showed that some difference of productivity per tiller occurred in different vegetations (P<0.05). The cumulate length of rhizomes and its biomass was the highest for the one year old class, and it decreased with an increased age, the storage of dry matter within per meter rhizome was the highest for the 1st (in H1) or 2nd (in H2 and H3) age class. The results showed that loosen and damp sandy soil was advantageous to the growth and storage of dry matter in rhizomes.