| 摘要: |
| 【目的】研究秦岭山地5种典型亚高山草甸物种的多样性，为该区域亚高山草甸的保护提供依据。【方法】以分布在秦岭火地塘林区、佛坪自然保护区、太白山自然保护区的野青茅(Deyeuxia arundinacea)、赖草(Leymus secalinus)、长穗苔草(Carex dolichostachya)、早熟禾(Poa annua)、细叶苔草(Carex rigescens)等5种亚高山草甸群落为研究对象，采用样方法进行调查取样，记录5种典型亚高山草甸群落的物种名称、高度、盖度、株数、海拔高度等相关数据，对5种草甸群落的物种组成及其重要值、丰富度、多样性指数和均匀度指数进行对比分析，并进行草甸群落植物物种组成的相似性分析；在太白山自然保护区不同海拔（1 700，2 000，2 300，2 600和2 900 m）高度设置样方，调查分析5种草甸群落的物种丰富度及物种多样性随海拔变化的规律。【结果】野青茅、赖草、长穗苔草、早熟禾、细叶苔草5种草甸群落的建群种分别为野青茅、赖草、长穗苔草、早熟禾、细叶苔草。5种亚高山草甸群落的物种丰富度分别为早熟禾草甸（18种）＞细叶苔草草甸（15种）＞赖草草甸（10种）＞长穂苔草草甸（8种）＞野青茅草甸（6种），Shannon-Wiener多样性指数H′和Simpson多样性指数D大小依次均为细叶苔草草甸（3.567，0.724）＞早熟禾草甸（3.321，0.653）＞长穗苔草草甸（2.365，0.584）＞赖草草甸（2.247，0.513）＞野青茅草甸（1.487，0.456），Pielou均匀度指数J为细叶苔草草甸（0.798）＞长穗苔草草甸（0.617）＞早熟禾草甸（0.513）＞赖草草甸（0.487）＞野青茅草甸（0.454）。5种草甸群落中长穗苔草草甸与早熟禾草甸的相似度最高，相似系数为0.222；早熟禾草甸与赖草草甸的相似度最低，相似系数为0.071。随着海拔高度的升高，物种丰富度呈现出先增高再降低的趋势，物种多样性指数变化趋势与之类似。【结论】5种秦岭山地亚高山草甸中，灌木和乔木物种相对较少，其对草甸物种丰富度的影响也相对较小,可以采用人工干预的方法增加物种丰富度，以维持并提高草甸资源的生产力和稳定性。 |
| 关键词: 秦岭 亚高山草甸 生物多样性 物种丰富度 多样性指数 |
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| Diversity of five mountain subalpine meadows in Qinling Mountains |
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DOU Quan-hu
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| Abstract: |
| 【Objective】The species diversity of five typical subalpine meadows in Qinling Mountains was studied to provide basis for regional protection of subalpine meadows.【Method】Investigation was conducted on five subalpine meadows including Deyeuxia arundinacea,Leymus secalinus,Carex dolichostachya,Poa annua,and Carex rigescens in Huoditang forest zone,Foping Nature Reserve and Taibai Mountain Nature Reserve of Qinling Mountain.Sample survey method was used to record species name,height,cover,number,altitude and other relevant data in the five subalpine meadows.Then,the species composition,important value,richness,diversity index and evenness index were analyzed and compared,and the similarity of species composition was analyzed.The change of species richness and diversity of meadow community along with elevation was also investigated by setting elevation plots at different altitudes (1 700,2 000,2 300,2 600,and 2 900 m).【Result】D.arundinacea,L.secalinus,C.dolichostachya,P.annua and C.rigescens were the constructive species of D.arundinacea meadow,L.secalinus meadow,C.dolichostachya meadow,P.annua meadow and C.rigescens meadow,respectively.The order of species richness was P.annua meadow（18）＞C.rigescens meadow（15）＞L.secalinus meadow（10）＞C.dolichostachya meadow（8）＞D.arundinacea meadow（6）,the order of Shannon-Wiener index H′ and Simpson index D was C.rigescens meadow（3.567,0.724）＞P.annua meadow（3.321,0.653）＞C.dolichostachya meadow（2.365,0.584）＞L.secalinus meadow（2.247,0.513）＞D.arundinacea meadow（1.487,0.456）,and the order of Evenness index J was C.rigescens meadow（0.798）＞C.dolichostachya meadow（0.617）＞P.annua meadow（0.513）＞L.secalinus meadow（0.487）＞D.arundinacea meadow (0.454).C.dolichostachya meadow and P.annua meadow had the highest siimilarity of 0.222,while P.annua meadow and L.secalinus meadow had the lowest similarity coefficient of 0.071.As the increase of altitude,species richness and diversity index increased firstly followed by decrease.【Conclusion】Among the five studied subalpine meadows,shrubs and trees were relatively less and the impact on species richness was also small.Manual intervention could increase the species richness and improve the stability and productivity of meadow resource. |
| Key words: Qinling subalpine meadow biological diversity species richness species diversity index |
