羊草草原不同退化程度植物群落内地上部分变化对群落根系的影响  

The effects of aboveground biomass variations on root system in in Leymus chinensis Steppe with different degradation degrees

作　　者：梁燕[1] 韩国栋[2] 周禾[1] 

机构地区：[1]中国农业大学动物科技学院,北京100094 [2]内蒙古农业大学生态环境学院,内蒙古呼和浩特010019

出　　处：《草业科学》2008年第4期110-115,共6页Pratacultural Science

基　　金：国家自然科学基金重点项目(30360022);国家自然基金项目(30440051)

摘　　要：应用逐步聚类分析（FASTCLUS）方法,对内蒙古自治区赤峰市克什克腾旗达里诺尔自然保护区境内的羊草Leymus chinensis草原进行定量划分。其结果为,从当地冬季打草场的围栏至居民点附近（由北到南）4100 m的距离范围内,有3段处于不同退化程度的草地植物群落,其距离范围分别为：0-1700 m,1700-2700 m,2700-4100 m。在此基础上,探讨了不同退化程度草地植物群落内地上生物量的变化,这种变化与地下生物量的关系及其对群落根系的影响。结果表明,地下生物量的变化并非随着人为干扰强度的加剧及地上生物量的减少而递减,而是表现为在适度放牧干扰的地段（0-1700 m）出现最大生物量;且地下生物量在不同退化程度草地植物群落内的差异,主要是由聚集于表层土壤中的根量引起的。FASTCLUS method was used to classify Leyrnus chinensis steppe in Dalinuoer natural reserve, Keshiketeng Banner of Chifeng City, Inner Mongolia. The grasslands were classified quantitatively into areas with different degrees of degradation according to plant community characteristics, which indicated there were three different degradation degrees with the distance of 0-1 700 m, 1 700-2 700 m and 2 700-4 100 m respectively. We explored the effects of aboveground biomass variations on root system among different communities. The results showed that underground biomass variations had no relevant decreasing tendencies with more human disturbances and less biomass aboveground. The area under moderate grazing pressures （0-1 700 m） had the maximum underground biomass. The differences of underground biomass among communities with different degradation degrees were mainly caused by root biomass accumulated in the layer of 0-10 cm top soil.

关 键 词：羊草草原 退化程度 群落 植物种类 地上生物量 地下生物量 根系分布 

分 类 号：S812[农业科学—草业科学]