盐碱土旱田改水田后其理化性质与微生物多样性差异

Difference of Physicochemical Properties and Microbial Diversity to Dryland being Reclaimed into Paddy Soil

黑龙江省有大面积的旱田改为水田种植水稻。为了探明盐碱土耕地旱田改水田后土壤理化性质和微生物多样性的差异,进而为盐碱土旱改水提供理论依据。以大庆地区旱田改水田3年后的盐碱土耕地作为研究对象,以土壤的pH、水溶性盐、有机质、全氮、有效磷、速效钾作为理化指标,利用16S rRNA基因扩增子高通量测序技术研究微生物多样性,结合土壤理化性质进行冗余分析。结果表明,盐碱土旱田改水田后,土壤pH由8.12显著上升至8.47,有效磷含量由3 mg·kg^-1显著上升至8.73 mg·kg^-1;细菌群落多样性降低,古菌群落多样性升高,其中变形菌门和泉古菌门为主要的优势菌门,贪噬菌属和Methanocella为主要的优势菌属;在旱田改水田过程中,pH是对微生物群落结构影响作用最大的环境因素,全氮含量与古菌群落结构变化相关性最大。

There is large area dry land changed to paddy fields for rice in Heilongjiang province.In order to find out the difference soil physical and chemical properties and microbial diversity after dry land changed to paddy fields in saline-alkali soil and provide the theoretical basis for improvement of saline-alkali soil,the physical and chemical indicators were detected such as pH value,water-soluble salt,organic matter,total nitrogen,available phosphorus,and available potassium in the saline-alkali soil that dry land changed to paddy fields after 3 years in Daqing area,and using 16S rRNA gene amplicon high-throughput sequencing technology to study microbial diversity,combined with soil physical and chemical properties for redundancy analysis.The results showed that,the soil pH value was increased from 8.12 to 8.47,the effective phosphorus content was increased from 3 mg·kg^-1 to 8.73 mg·kg^-1.The diversity of bacterial community decreased,and the diversity of archaea community increased.The Proteobacteria and Parvarchaeota were major dominant bacterium,and the Variovora and Methanocella were major dominant genus.The pH value is the most important environmental factor affecting the microbial community structure,and the total nitrogen content is the most relevant to the changes in the archaeal community structure.