新疆部分地区盐碱荒漠化土壤养分及放线菌区系组成

Nutrient Contents and Actinomycetes Populations of Desert Saline-alkali Soil in Parts Regions of Xinjiang

采用常规方法研究了新疆部分地区盐碱荒漠化土壤的养分状况及放线菌区系组成,结果表明:有机质平均含量中等偏低,并按碱土、砾石质碱土、沙壤盐土、沙土顺序依次递减;全氮平均含量按照碱土>砾石质碱土>沙土>沙壤盐土排列;其速效养分变化无明显规律;pH值均在8左右;水溶性总盐平均含量以沙壤盐土最高,分别为碱土、砾石质碱土、沙土的17.5、58.0、30.1倍。在碱土、砾石质碱土、沙土中,GA培养基分离的放线菌数量要大于GA′培养基所分离的放线菌数量,而在沙壤盐土中则相反;供试土样的链霉菌共可分为12个类群,其中优势类群为烬灰类群,每一类群在不同供试土样中的分离率也不同,白孢类群的分离率最高。土壤速效磷的含量与放线菌的数量和种类之间呈显著正相关,土壤速效氮的含量与放线菌的数量之间呈正相关,总盐的含量与放线菌的数量和种类之间呈负相关;通径分析表明:速效磷对GA′培养基上放线菌的数量及放线菌的种类分布影响最大,有机质对GA培养基上放线菌的数量分布影响最大。

The study on the in parts regions of Xinjiang level and decreased gradual nutrient contents and actinomycetes populations of desert saline-alkali soils showed that soil organic matter average contents were lower than middle ly in this order： solonetz soils, gravel solonetz soils, sand saline soils and sand soils; Soil total nitrogenous average contents increased in this order： solonetz soils〉gravel solonetz soils〉sand soils〉sand saline soils, while available nutrients contents varied slightly. Soil pH value varied around 8; Soil total salt average contents were highest in sand saline soils, being 17.5, 58.0 and 30.1 times higher in sand saline soils than in solonetz, gravel solonetz and sand soils,respectively. The quantities of soil actinomycetes isolated from GA medium were higher than from GA＇medium in solonetz, gravel solonetz and sand soils,but in sand saline soils, the quantities of soil actinomycetes isolated from two mediums were contrary. The main isolated actinomycetes were Streptomyces, Streptomyces could be classified into 12 kinds and Cinerogriseus was the dominant group. Isolation rate of each group was different in different soil samples, and Albosporus was the highest. In additiom, The positively significant correlation were found out between the contents of soil available phosphorus and the quantities and species of soil actinomycetes, the contents of soil available nitrogenous were correlated with the quantities of soil actinomycetes isolated from GA＇medium positively, the contents of soil total salt were correlated with the the quantities and species of soil actinomycetes negatively;soil available phosphorus had most effect on the quantities of soil actinomycetes isolated from GA′medium and the species of soil actinomycetes, soil organic matter had most effect on the the quantities of soil actinomycetes isolated from GA medium.