塔里木盆地北缘绿洲-荒漠过渡带典型植物群落物种多样性分析

摘要

[目的]本文探索了绿洲-荒漠过渡带典型植物群落空间格局分布及其土壤环境特征,揭示二者之间的响应关系,为保证绿洲的稳定发展与区域水土资源的可持续发展提供理论指导.[方法]以塔里木盆地北缘绿洲-荒漠过渡带典型植物群落作为研究对象,通过野外调查、样品采集和室内分析,运用丰富度指数、多样性指数、均匀度指数以及优势度指数,对典型植物群落物种多样性进行统计分析.[结果]①典型植物群落的物种多样性在不同区域上,按低盐区＞中盐区＞高盐区的顺序依次递减.②柽柳、盐节木和盐穗木等乔灌木群落的丰富度指数、多样性高于芦苇、骆驼刺等草本植物群落;对于均匀度指数和优势度指数,柽柳、盐节木和盐穗木群落在不同区域上均呈现出相同的变化规律,而芦苇和骆驼刺群落在不同区域上的变化较为复杂.这一现象说明乔、灌木群落的生物多样性特征更加稳定,草本群落则受生境的影响显著.③柽柳、盐穗木与盐节木植物群落是该绿洲-荒漠过渡带的原生植物群落,芦苇、骆驼刺为次生植物群落,另外还伴有少量的白刺、花柴等物种.[结论]典型植物群落物种多样性受研究区域土壤含盐量、含水量等环境因子的影响,乔灌木特征较稳定,草本群落易受环境的影响.研究结果可为绿洲的稳定发展与区域水土资源的可持续发展提供理论指导.%[Objective] This paper aimed to explore the spatial pattern distribution of typical plant communities and soil environmental characteristics,revealed the response relationship between them in oasis desert transitional zone and provide a theoretical guidance for the stable development of oasis and the sustainable development of regional water and soil resources.[Method] Typical plant communities in the oasis-desert transition zone of the northern Tarim basin were used as tested objects,based on field investigation,sample collection and indoor analysis,the species diversity of typical plant communities by the species richness index,diversity index,evenness index and dominance index were analyzed.[Result] (i) The species diversity of typical plant communities in different areas decreased in accordance with the order:low salinity area ＞ moderate salinity area ＞ higher salinity area.(ii) Through the comprehensive analysis of five typical plant species diversity,the richness index,diversity of the arbor and shrub communities such as Tamarix ramosissima,Halocnemum strobilaceum and Halostachys caspica were higher than those of the herbaceous plants such as Phragmites australis and Alhagi sparsifdia.For the evenness index and dominance index,the shrub community such as Tamarix ramosissima,Halocnemum strobilaceum and Halostachys caspica showed the same change pattern on the different areas,while the Phragmites australis and Alhagi sparsifdia communities were more complicated on the different areas.This phenomenon showed that the biodiversity characteristics of arbor and shrub communities were more stable,and herbaceous communities were affected significantly by habitat.(iii) The dominance of Tamarix ramosissima,Halocnemum strobilaceum and Halostachys caspica communities were the primary plant communities in the oasis-desert transitional zone,Phragmites australis and Alhagi sparsifdia as secondary plant community,also accompanied by a small amount of Nitraria tangutorum Bobr.and Karelinia caspia (Pall.) Less.,et al.[Conclusion]The species diversities of typical plant communities were affected by environmental factors such as the salt content,water content and other environmental factors of soil in the study area.The characteristics of arbor were stable,and the herbaceous communities were susceptible to the environment.The research results would be provided a theoretical guidance for the stable development of oasis and the sustainable development of water and soil resources in the region.