青藏高原东缘异针茅草地群落组成及生产力研究

于2002-2004年对青藏高原东缘异针茅草地群落植被结构特征(植物种群优势度和群落物种数与生态优势度)、种群和群落生物量及其构成进行了系统研究。结果表明,异针茅草地植被组成复杂,主要由中旱生和耐寒中生植物组成,以异针茅为优势种,羊茅为亚优势种;草地中平均优势度大于0.150的植物有12种,伴生种种类多。草地植物种群和群落地上植物量月动态变化均呈先增加后降低的单峰曲线变化模式,生物量峰值出现于7-9月,种群生物量月动态存在植物种间分异。随利用年限的增加,草地群落植物组成逐渐由复杂群落向简单群落演替,群落生产力逐渐降低。

Studies community composition and productivity in eastern edge of Qinghai-Tibetan Stipa aliena grassland

Vegetative structure(population dominance,community species and ecological dominance),biomass,its composition of population and plant community of Qinghai-Tibetan Stipa aliena grassland were studied.The results showed that plant species of S.aliena grassland were mesoxerophtyes and cold-resistant mesophytes,dominant and sub-dominant species were S.aliena and Festuca ovina respectively.There were many kinds of companion species and the dominance of 12 species were >0.150.Above-ground biomass dynamic of main species and plant community appeared a single-peaked curve along with growth stage,and existed different among different species.There appeared the highest values in bloom growth stage(from July to September).With the number of utilizing years increased,grassland plant composition succeeded from complex community to simple community,and grassland productivity decreased.