冷蒿种群在不同放牧强度胁迫下构件的变化规律  

Variation of module of Artemisia frigida population under different grazing intensities

作　　者：杨持[1] 宝音陶格涛[1] 李良[1] 

机构地区：[1]内蒙古大学生态与环境科学系,呼和浩特010021

出　　处：《生态学报》2001年第3期405-408,共4页Acta Ecologica Sinica

基　　金：国家自然科学基金!资助项目 ( 39760 0 2 0 )

摘　　要：在中国科学院草原生态系统定位研究站的羊草草原放牧退化系列上 ,选定无放牧 (已围栏保护了 2 0 a的羊草样地 )、轻度放牧、中度放牧、重度放牧的不同牧压梯度地段 ,采用样方法调查冷蒿的构件数量特征。结果表明 :冷蒿的营养枝数、不定根数、匍匐茎长在 4个梯度上均有显著差异 ,而且都随牧压增大而增加 ,但不定根间的平均距离 (匍匐茎长 /不定根数 )与营养枝数 /不定根数两项却不随牧压变化而变化。就生物量而言 ,各构件干重在 4个梯度间也有显著差异 ,而且随牧压增大而增加。在相应梯度上所做的 2 5cm× 2 5cm× 1 0 cm土体根量数据亦有相似的规律。The quantities of modulus of Artemisia frigida populations were sampled in the series of grazing gradient with no grazing (having been protected for twenty years by pen), mild grazing , moderate grazing , and heavy grazing in a Leymus chinensis grassland near the Inner Mongolia Grassland Ecosystem Research Station. The results are as follows: along this gradient, Artemisia frigida individuals hada significant difference in quantities of vegetative tillers , quantities of adventitious roots and length of stolen, and increased with grazing pressure increase. In contrast, the average distance between adventitious roots (length of stolen/number of adventitious roots) and the ratio of number of vegetative tillers to the number of adventitious roots did not change with a grazing pressure. As biomass was concerned, dry weight of modules of individuals were significantly different along the gradient, and biomass increased with grazing pressure too. The biomass wich was sampled from 25cm×25cm×10cm soil under four different grazing intensities rose with grazing pressure in the same way.

关 键 词：冷蒿 构件 牧压梯度 菊科 放牧强度 种群 

分 类 号：Q945.78[生物学—植物学]