施肥旱作农田土壤中人类病原菌群落组成及动态变化特征

Composition and dynamic change characteristics of human pathogenic communities in dryland farmland with manure application

采集浙江省杭州、嘉兴、衢州、金华、龙游5个地区长期施用鸡粪、猪粪或化肥的农田土壤进行室内培养实验,然后采用高通量测序及序列比对方法分析供试土壤细菌和人类病原菌(human pathogenic bacteria,HPB)群落组成,旨在进一步探究施用粪肥后土壤中HPB群落组成差异及动态变化特征。结果表明:在160个供试土壤样品和2种粪肥样品中共比对到75种HPB,其中优势HPB为巨大芽孢杆菌(Bacillus_megaterium_QM_B1551,24.2%)和拜氏梭菌(Clostridium_beijerinckii_NCIMB_8052,23.1%);施用猪粪处理的土壤中细菌和HPB的香农(Shannon)指数均有所降低,而施用鸡粪或化肥处理的土壤中细菌和HPB多样性无明显变化。主坐标分析结果表明,施用粪肥处理的土壤细菌群落组成与未施肥对照之间具有显著差异,尤其是施用猪粪处理差异最显著(P<0.001);土壤样品间共有HPB占所有HPB的22.7%;施用粪肥处理的土壤中大部分HPB的相对丰度高于未施肥对照,并随培养时间的延长而不断下降。方差分解分析结果表明,土壤理化性质、细菌群落及两者交互作用是土壤中HPB变异的重要因素。综上所述,施用粪肥处理的土壤中HPB的变化特征主要受肥料类型、土壤类型、土壤理化性质及固有细菌群落的影响。

To understand the community structure composition and dynamic change characteristics of human pathogenic bacteria(HPB)in soils after manure application,laboratory cultivation experiments were conducted on agricultural soils with long-term application of chicken manure,pig manure,or chemical fertilizer in five regions of Hangzhou,Jiaxing,Quzhou,Jinhua,and Longyou in Zhejiang Province,and the community compositions of the soil bacteria and HPB were analyzed by high-throughput sequencing and sequence alignment methods.The results showed that a total of 75 HPB were detected in 160 soil samples and two manure samples,and the dominant HPB were Bacillus_megaterium_QM_B1551(24.2%)and Clostridium_beijerinckii_NCIMB_8052(23.1%).The Shannon indexes of bacteria and HPB in the soils decreased after the application of pig manure,while the diversities of bacteria and HPB in the soils with the application of chicken manure or chemical fertilizer had no significant changes.The results of the principal coordinate analysis showed that there was a significant difference in the bacterial community composition of soils between the manure treatment and the unfertilized control,especially in the pig manure treatment(P<0.001);22.7%of all HPB were shared among the soil samples;and the relative abundance of most HPB in the soils treated with manure was higher than that in the unfertilized control,and it decreased continuously with the extension of cultivation time.The results of the variance partitioning analysis showed that soil physicochemical properties,bacterial communities,and their interactions were important factors contributing to the variation of HPB in the soils.In summary,the HPB variation characteristics in soils treated with manure are influenced mainly by manure types,soil types,soil physicochemical properties,and inherent bacterial communities.