不同土壤类型下AM 真菌分布多样性及与土壤因子的关系

以禾本科植物群落为研究对象, 研究了宁夏六盘山林地、银川农耕地、暖泉农耕地、固原农耕地、盐池沙地、灵武沙地6 个采样地点5 种土壤类型(黑垆土、灌淤土、黄绵土、灰钙土、风沙土)下AM 真菌物种多样性及其与土壤因子的关系。结果表明: 5 种土壤类型采样点的植被根际土壤中共鉴定出5 属48 种AM真菌, 其中, 无梗囊霉属(Acaulospora)1 种, 巨孢囊霉属(Gigaspora)3 种, 球囊霉属(Glomus)37 种, 类球囊霉属(Paraglomus)1 种, 盾巨孢囊霉属(Scutellospora)6 种, 各采样点土壤均以球囊霉属为优势属。地球囊霉(G.geosporum)和木薯球囊霉(G. manihotis)是6 个采样地点中的优势种。不同土壤类型各采样点AM 真菌各属的频度存在明显差异, 球囊霉属在各点均有出现, 频度值最高。具有较高植被多样性的暖泉样点, AM 真菌的种属数量较多。土壤环境因子对AM 真菌孢子密度的影响因所处土壤、植被类型不同而异。pH、全盐、速效钾、速效磷等土壤肥力因子, 在PCA 轴上能最大程度地解释AM 真菌孢子密度与土壤环境因子之间相互关系的大部分信息。宁夏不同土壤类型区域中AM 真菌种类及分布一定程度上与该采样点的植被类型、植物多样性和土壤肥力特征相对应。

Arbuscular mycorrhizal fungi diversity and its relationship with soil environmental factors in different soil types

Rhizospheric soil samples were collected from 5 soil types (dark loessial soil, cumulated irrigated soil, cultivated loessial soil, sierozems and aeolian soil) in 6 sampling sites (Liupanshan Mountain forest land, Yinchuan farmland, Nuanquan farmland, Guyuan farmland, Yanchi desert and Lingwu desert) with gramineae vegetation communities. Then the relationship between Arbuscular mycorrhizal Fungi (AMF) diversity and soil environmental factors was investigated. Based on spore morphological characteristics, a total of 5 genera and 48 species of AMF were found in five soil types. Specifically, there were 1 Acaulospora, 3 Gigaspora, 37 Glomus, 1 Paraglomus and 6 Scutellospora species. From the 6 sampling sites, Glomus was the most dominant genera and G. geosporum and G. manihotis were the most dominant species. Obviously differences were noted in AMF genus frquencies at each sampling site. Glomus was found at every site, its frequency was the highest. Nuanquan farmlands with high plant diversities had relatively high AMF species abundance and diversity. The effects of soil environmental factors on AMF spore density changed with soil and vegetation type. Based on axial principal analysis, total salt, pH, available potassium and available phosphorus mostly explained the relationship between AMF spore density and soil fertility. To a certain degree, the species and distribution of AMF corresponded with vegetation type, plant diversity and soil fertility at the various sampling sites.