放牧对伊犁绢蒿种群有性繁殖特性的影响

Sexual productive characteristic of Seriphidium transiliense community under grazing conditions

以蒿类荒漠草地建群种伊犁绢蒿(Seriphidium transiliense)为对象,研究了放牧对伊犁绢蒿的构件数量特征、形态、生物量及其分配格局的影响。结果表明,与封育相比,放牧条件下伊犁绢蒿个体植株高度下降,丛幅径减小,地上生物量(茎、叶、花/种子)下降;放牧促进伊犁绢蒿生物量向茎的分配比例增加,减少了向叶、花/种子的分配,生物量分配趋势为茎>叶>花/种子;伊犁绢蒿种群结实率、单株结实率、花序长、小花数都呈下降趋势。

A study was conducted to investigate the influence of grazing on representative plant Seriphidi- umt ransiliense in Xinjiang desert grassland. The number of components of S. transiliense and other char- acteristics such as morphology, biomass and their distribution pattern under grazing condition were ana- lyzed. The results showed that individual plant height, bundle of diameter and the ground biomass [inclu- ding stem, leaf, and flower （seeds）] of S. transiliense decreased under grazing condition compared with the enclosed condition. The distribution ration of stem biomass increased and the distribution ration of leaf and flower （seeds） biomass decreased under grazing condition. The ratio of stem biomass was higher, which induced to lower ratio of flower seeds biomass. The seed setting rate, seed rate per plant, spike length, number of florets of S. transiliense decreased with condition.