长期稻虾轮作对稻田土壤细菌群落的影响

Effects of long-term rice-crayfish rotation on soil bacterial community structure

为探究长期稻虾轮作对稻田土壤理化性质及细菌群落结构的影响,基于化学分析方法和16S rRNA扩增子高通量测序技术,研究了水稻单作与4、8和21年稻虾轮作稻田土壤理化性质及细菌群落结构,并分析了细菌群落结构与土壤理化性质之间的关系。结果显示,相较于水稻单作模式,稻虾轮作稻田土壤总磷含量提高37.01%~54.33%(P<0.05),但土壤速效磷含量降低60.21%~61.10%(P<0.05)。主坐标分析和置换多元方差分析结果显示,不同年限稻虾轮作稻田土壤细菌的群落结构差异显著(P=0.004)。长期稻虾轮作显著增加了稻田土壤Aminicenantia(纲、目、科、属)和Sva0485(纲、目、科、属)的相对丰度。冗余分析表明,有机质和碱解氮是影响稻田土壤细菌群落结构的关键环境因子。研究表明,稻虾轮作增加了稻田土壤总磷含量,降低了土壤速效磷含量,长期稻虾轮作没有改变土壤细菌群落的多样性,但却改变了细菌不同门类的相对丰度。本研究可为阐释稻虾轮作模式对稻田土壤细菌群落的影响机制提供科学依据。

We investigated the impacts of long-term rice-crayfish rotation on physicochemical properties and bacterial community structure in paddy soils.Chemical analysis methods and high-throughput sequencing of 16S rRNA amplicons were employed to examine the soil physicochemical properties and bacteria community structures in rice monoculture and rice-crayfish rotation systems with durations of 4,8,and 21 years.Results showed that rice-crayfish rotation significantly increased total phosphorus content by 37.01%-54.33%(P<0.05),but decreased available phosphorus content by 60.21%-61.10%(P<0.05)compared to rice monoculture.Results of principal coordinate analysis and multivariate analysis of variance showed significant differences in soil bacteria community structure across systems with different rotation years(P=0.004).Long-term rice-crayfish rotation increased the relative abundance of Aminicenantia(family,order,class,genus)and Sva0485(family,order,class,genus)in paddy soil.Redundancy analysis(RDA)results identified organic matter and available nitrogen as key factors influencing bacterial community structure.Overall,rice-crayfish rotation affected soil phosphorus levels and altered the abundance of bacterial phyla,without impacting community diversity in soil bacteria.Our results provide valuable insights into the impact of rice-crayfish rotation on paddy soil bacterial communities.