放牧干扰下两河源牧区草地群落多样性与生物量的关系及变化  

Relationships and Changes of Grassland Community Diversity and Biomass in the Pasture Area of the Two Rivers Under Grazing Disturbance

作　　者：陈维龙 叶茂[1,2] 潘晓婷 李苗苗 曾国燕 贺清智 张西 CHEN Weilong;YE Mao;PAN Xiaoting;LI Miaomiao;ZENG Guoyan;HE Qingzhi;ZHANG Xi(College of Geographical Science and Tourism,Xinjiang Normal University,Urumqi 830054,Xinjiang,China;Xinjiang Lake Environment and Resources Laboratory in Arid Areas,Urumqi 830054,Xinjiang,China)

机构地区：[1]新疆师范大学地理科学与旅游学院,新疆乌鲁木齐830054 [2]新疆干旱区湖泊环境与资源实验室,新疆乌鲁木齐830054

出　　处：《西北林学院学报》2025年第1期198-208,共11页Journal of Northwest Forestry University

基　　金：国家自然科学基金(42161004);NSFC-新疆联合基金项目(U1803245)。

摘　　要：放牧会影响植物群落特征及地上生物量与多样性之间的关系,是近年来草地生态系统研究的热点问题。本研究以两河源牧区草地为例,基于60个采样点,采用样方法对该牧区的草地植被进行调查,使用α-多样性指数测度分析了放牧对植物群落结构特征的影响,探讨植物群落物种多样性与地上生物量之间的关系及变化。结果表明:1)在自然放牧条件下,两河源牧区植物科属种数量降低,植物群落高度和盖度呈下降趋势(P<0.01),密度呈上升趋势(P<0.01)。2)放牧显著降低了植物群落地上生物量(P<0.01)。其中,禾草类植物群落地上生物量降低,杂草类植物群落地上生物量提高,豆科类植物群落地上生物量的变化不大。3)放牧对两河源牧区植物群落产生了显著的影响,导致植物群落物种丰富度、优势度和多样性降低,但群落物种数量的分布更加均匀。4)植物群落地上生物量与Margalef丰富度指数、Shannon-Wiener多样性指数和Alatalo均匀度指数呈极显著正相关关系(P<0.01),与Simpson优势度指数呈极显著负相关关系(P<0.01)。放牧干扰下,植物群落地上生物量与物种多样性之间的关系依然显著。因此,在草地的管理和维护中,应考虑放牧对植物群落结构特征的影响,根据当地实际情况做出合理的应对政策。研究结果为两河源牧区草地维护、管理及生态系统的可持续发展提供理论依据。Grazing affects the characteristics of plant communities and the relationship between aboveground biomass and diversity,which has been become a hot issue in grassland ecosystem research in recent years.In this study,we investigated the grassland vegetation in the pasture area of the two river sources based on the data collected from 60 sampling points,and used the sampling method to analyze the effects of grazing on the structural characteristics of plant communities using theα-diversity index,and to explore the relationship between species diversity and above-ground biomass(AGB)of plant communities and their changes.The results showed that 1)under natural grazing conditions that may result over stocking,the number of plant families and genera in the pasture area of the two river sources decreased,the height and cover of the plant community showed a decreasing trend(P<0.01),and the density showed an increasing trend(P<0.01).2)Grazing significantly reduced the AGB of plant communities(P<0.01).The AGB of the grass community decreased,the AGB of the weed community increased and the AGB of the legume community did not change significantly.3)Grazing had a significant impact on the plant communities in the pastoral areas of the two river sources,resulting in a decrease in species richness,dominance and diversity of the plant communities,but a more even distribution of the number of community species.4)The AGB of plant communities showed highly significant and positive correlations with Margalef's richness index,Shannon-Wiener's diversity index and Alatalo's evenness index(P<0.01),and highly significant and negative correlations with Simpson's dominance index(P<0.01).The relationship between AGB and plant community species diversity remained significant under grazing disturbance.Therefore,in grassland management and conservation,the effect of grazing on the structural characteristics of plant communities should be taken into account,and appropriate response policies should be made according to the actual local situatio

关 键 词：放牧 植物群落结构 多样性指数 地上生物量 两河源牧区 

分 类 号：S812[农业科学—草业科学]