半干旱黄土高原生态区不同土地利用类型土壤可培养微生物群落分析

Analysis of culturable microbial communities in different land utilization types in semi-arid loess plateau ecological zones

对半干旱黄土高原生态区山地干草原、耕地和河谷荒地等不同利用类型土壤可培养微生物进行了研究,结果发现山地干草原土壤可培养细菌、放线菌、真菌数量分别为6.43×10~6cfu·g^(-1)、2.68×10~6cfu·g^(-1)和0.11×10~6cfu·g^(-1),耕地分别为9.27×10~6cfu·g^(-1)、5.33×10~6cfu·g^(-1)和0.07×10~6cfu·g^(-1),河谷荒地分别为2.35×10~6cfu·g^(-1)、2.36×10~6cfu·g^(-1)和0.08×10~6cfu·g^(-1)。山地干草原可培养细菌包括厚壁菌门(Firmicutes)、放线菌门(Actinobacteria)和α变形菌纲(Alphaproteobacteria)的芽孢杆菌属(Bacillus)、微杆菌属(Microbacterium)、节杆菌属(Arthrobacter)和农杆菌属(Agrobacterium),优势菌属为芽孢杆菌属(69.23%),耕地为厚壁菌门、放线菌门、α变形菌纲和γ变形菌纲(Gammaproteobacteria)的芽孢杆菌属、农杆菌属、葡萄球菌属(Staphylococcus)、节杆菌属、假单胞菌属(Peseudomonas),河谷荒地包括厚壁菌门和放线菌门的节杆菌属、葡萄球菌属和类芽孢杆菌属(Paenibacillus),以葡萄球菌属为主(50.00%)。不同类型土壤放线菌以链霉菌属(Atreptomyces)为主,其余包括链孢囊菌属(Streptosporangium)、链轮丝菌属(Streptoverticillium)和小单孢菌属(Micromonspora)。霉菌以青霉属(Penicillium)为主,其余包括曲霉属(Aspergillus)、芽枝霉属(Cladosporium)、毛霉属(Mucor)、镰孢霉属(Coniothecium)和交链孢霉属(Alternaria)。

The quantity and community distributions of the cultivable microorganisms in soils of different land uti- lization types （ upland meadow, cultivated land and river valley land） in typical semi - arid loess plateau biota in Northwest China were studied. The results showed that soil microbial populations are significantly different among various lands. The numbers of cuhurable bacteria, actinomycetes and fungi in the upland meadow were 6.43 × 10^6cfu · g^-1, 2.68 × 10^6cfu · g^-1 and 0.11 × 10^6cfu · g^-1, respectively. The numbers in cultivated land were 9.27 × 10^6cfu · g^-1, 5.33× 10^6cfu · g^-1 and 0.07 × 10^6cfu · g^-1 , respectively. In the river valley land the numbers of culturable bacteria, actinomycetes and fungi were 2.35 × 10^6cfu · g^-1 , 2.36× 10^6cfu · g^-1 and 0. 08 × 10^6cfu · g^-1, respectively. The cultivable bacteria of upland meadow belonged to three phylogenetic groups of Firrnieutes, Actinobacteria and Alphaproteobacteria, including Bacillus, Microbacterium, Arthrobacter and Agrobacterium, with the main genus being Bacillus （69.23 % ）. The bacteria from the cultivated land were affili- ated with Firmicutes, Actinobacteria, Alphaproteobacteria and Gammaproteobacteria, including Bacillus, Agrobacterium, Staphylococcus, Arthrobacter and Peseudomonas. The isolates from the river valley land belonged to Firmicutes and Actinobacteria including Arthrobacter, Staphylococcus and Paenibacillus, with the main genus being Staphylococcus （50.00%）. The isolated actinomycetes belonged to the following four genera ： Streptospor- angium, Atreptomyces, Streptoverticillium and Micromonspora, with the main genus being Atreptomyces. The cul- turable fungi were placed in six main groups including Penicilliurn, Aspergillus, Cladosporium, Mucor, Coniothe- cium and Alternaria, with the main genus being Penicillium.