喀斯特不同植被恢复阶段土壤AMF组成及多样性研究

Composition and Species Diversity of AMF in Different Vegetation Restoration Stages in Karst Region

选择贵州花江、织金、花溪3个典型喀斯特地段的不同恢复阶段(乔木、灌木和草本)土壤丛枝菌根真菌(arbuscular mycorrhizal fungi,AMF)为研究对象,基于AMF孢子的形态鉴定,计算AMF孢子密度、分离频度、物种丰度、重要值、物种均匀度指数及Shannon-Wiener多样性指数,研究喀斯特不同恢复阶段土壤AMF物种组成及多样性。结果表明:3个采样地段共分离AMF菌种4目8科10属68种,其中球囊霉属(Glomus)数量最大达35种,其次是无梗囊霉属(Acaulospora)为17种,巨孢囊霉属(Gigspora)、类球囊霉属(Paraglomus)及原囊霉属(Archaeospora)各1种;不同采样地段各植被恢复阶段的优势种不同,所有样地中层状球囊霉Glomus lamellosum具有最大的相对丰度、分离频度和重要值;AMF种分类水平上,花江样地不同恢复阶段AMF丰度表现为乔木>灌木>草本,织金样地为灌木>草本>乔木,花溪样地为灌木>乔木>草本;不同植被恢复阶段土壤AMF均匀度指数和香农多样性指数在花江和织金多表现为乔木>灌木>草本,花溪样地Shannon-Wineer指数则是灌木显著高于乔木和灌木阶段。研究表明,喀斯特土壤中因异质生境条件的差异AMF菌种组成和物种多样性具有较大的差异。

The arbuscular mycorrhiza fungi（AMF）was researched as an object in karst soil of different vegetation restoration stages（tree,bush and herb）of three typical karst sites（Huajiang,Zhijin and Huaxi）,which were located in Guizhou province.Some indexes such as species abundance,spore density,relative isolation frequency,important value,species evenness index and sample Shannon-Wiener diversity index were calculated after morphological identification,in order to explore the composition features and AMF species diversity in vegetation restoring process.The results showed as follows：The experimental soil totally contained 68 species of 10 genera,8families and 4orders,and Glomus is the biggest genus by 35 species,and the second was Acaulospora（17species）,when Gigspora,Paraglomus and Archaeospora only have 1species respectively in this study.Specially,Glomus lamellosum had biggest species abundance,relative isolation frequency and important value in all AMF species,which it was as an dominant species in three sampling sites.At the AMF species level,the abundance presented TreeBushHerb in Huajiang,BushHerbTree in Zhijing,BushTreeHerb in Huaxi.The evenness index and Shannon-Wiener index of AMF species in different stages presented treeBushHerb in Huajiang and Zhijing sites,however the ShannonWiener index in Huaxi site significantly higher than tree and shrub stages.We suggested that the differences of heterogeneous conditions may affect on composition and diversity of AMF species.