东乌珠穆沁旗草地地上现存量与物种多样性的变化关系

Relationship between Aboveground StandingCrop and Species Diversity in East Ujimuqin Banner Grassland

为探究东乌珠穆沁旗(简称东乌旗)草地生产力与物种多样性的关系,掌握草地植物群落的稳定性,以东乌旗草地为研究对象,结合33个家庭牧场天然草地,共计168个样地数据,分析了地上现存量与群落密度、物种数、Margalef指数和Shannon-Wiener指数关系,计算植物群落稳定性,探讨其变化规律及变化趋势。研究表明:伴随地上现存量增加,东乌旗草地植物群落密度呈下降趋势;物种数、Margalef指数和Shannon-Wiener指数均呈先增加后平稳的变化趋势。东乌旗草地地上现存量大于37 g·m^(-2)时,植物群落的稳定状态基本不变。东乌旗草地植物群落物种多样性与生产力符合单调假说,草地植物群落空间异质性、物种间的竞争强度较弱。

In order to clarify the relationship between grassland productivity and species diversity in East Ujimqin Banner and grasp the ecology stability of grassland plant communities,the study took East Ujimqin Banner grassland as the research object,combined with data from 168 samples in 33 family pastures,analyzed the relationship between standing crop and community density,species number,Margalef index and Shannon Wiener index,calculated the plant community stability,and explored their variation trends and rules.The results showed that w ith the increasing of aboveground standing crop,the plant communities density in East Ujimqin Banner grassland presented a downtrend,the species number,Margalef index and Shannon-Wiener index presented a trend of increasing first and then stabilizing.When the aboveground standing crop in East Ujimqin Banner grassland exceeded 37 g·m^(-2),the stable state of plant community remained essentially constant.The species diversity and productivity of plant communities in East Ujimqin Banner grassland conformed to the monotonic hypothesis,with weak spatial heterogeneity and intensity of competition among species.