新疆沙冬青AM真菌物种多样性空间异质性研究

Diversity and Spatial Heterogeneity of Arbuscular Mycorrhizal Fungi in the Rhizosphere of Ammopiptanthus nanus

2012年6月选取新疆乌恰县康苏、膘尔托阔依（阴阳面）和上阿图什4个样地，分别采集新疆沙冬青（Arnmopiptanthus nanus）根嗣0～50cm土层土壤样品，研究了新疆沙冬青AM真菌物种多样性空间变化规律。共分离鉴定AM真菌4属44种，其中球囊霉属（Glomus）28种，无梗囊霉属（Acaulospora）11种，盾巨孢囊霉属（Scutellospora）4种，巨孢囊霉属（Gigaspora）1种，优势菌种为网状球囊霉（G．reticulatum）。AM真菌孢子密度低、体积小、孢壁厚、整体形态不饱满，表现出明显的旱生特征。膘尔托阔依（阴）样地的孢子密度最大，显著高于上阿图什样地（Pd0．05），极显著高于与膘尔托阔依（阳）和康苏样地（_Pd0．01）；康苏、膘尔托阔依和上阿图什样地的种丰度依次升高且差异显著；康苏、膘尔托阔依（阳）和上阿图什样地的Simpson多样性指数无显著差异（P〉0．05），却显著高于膘尔托阔依（阴）样地；膘尔托阔依（阴）和上阿图什样地的Shannon-wiener多样性指数显著高于其他样地（Pd0．05）；膘尔托阔依（阳）、膘尔托阔依（阴）和康苏、上阿图什样地的均匀度指数依次显著升高（P〈0．05）。土壤因子中速效磷与种丰度有极显著负相关，pH值与种丰度、Shannonwiener多样性指数和均匀度指数极显著正相关，水溶性全盐与Shannon-wiener多样性指数和均匀度极显著负相关，全氮与种丰度极显著负相关。结果表明，新疆沙冬青AM真菌物种多样性具有明显的空间异质性，与其土壤环境密切相关，pH值是影响新疆沙冬青AM真菌多样性的最主要土壤因子。

The study was used to discuss the change law of diversity and spatial heterogeneity of AM fun- gi in the Arnmopiptanthus nanus. Four genera and 44 species of AM fungi were isolated and determined from the soil samples of four different sites,which there were Glomus 28 species,Acaulosporall species, Scutellospora4 species,Gigaspora 1 species, G. reticulatum was the predominant species. The spore was characterized by its low density,small shape,thick wall and un-full overall shape,that indicated AM fungal spore had the obvious ecological adaptability.The highest spore density of AM fungi was at Biaoertuokuoyi （yin） site,and was significantly higher than other sites.The species richness of Kangsu,Biaoertuokuoyi and Shangatushi sites increased successively and had significant difference. The Simpson＇s diversity index at Kangsu,Biaoertuokuoyi（yang） and Shangatushi sites hadn＇t significant difference.The Shannon-wiener di- versity index at Bieoertuokuoyi（yin） and Shangatushi sites were significantly higher than others.The even- ness at Biaoertuokuoyi（yang）, Biaoertuokuoyi（yin）, Kangsu and Shangatushi sites increased significantly in turns. Available P had significantly negative correlations with species richness. Soil pH had significantly positive correlations with species richness.Soluble salt had significant negative correlations with Shannon diversity and Evenness indices.Total N had significant negative correlations with species richness. Our re- sults suggest that the species diversity of AM fungi in the rhizosphere of A.nanus had obvious spatial het- erogeneity and had close correlations with its soil environment, so that pH was the most important, and pH was the most important soil factor that affect the species diversity of AM fungi in the rhizosphere of A. ganus .