若尔盖国家自然公园四川片区不同生境下土壤细菌群落结构及多样性分析

Soil bacterial community structure and diversity under different habitats in Sichuan area of Zoige National Natural Park

[目的]揭示若尔盖国家自然公园四川片区不同生境下土壤细菌的群落结构及物种多样性。[方法]以若尔盖国家公园四川片区不同生境下的5种土壤(沼泽土、亚高山草甸土、草甸土、褐土和风沙土)为研究对象,借助高通量测序技术对土壤细菌多样性和群落结构进行分析,并讨论土壤理化性质与菌群结构的关系。[结果](1)在土壤细菌分类研究中,共鉴定出36个门,其中优势菌群为放线菌门(Actinobacteriota)、变形菌门(Proteobacteria)、厚壁菌门(Firmicutes)、酸杆菌门(Acidobacteriota)和绿弯菌门(Chloroflexi)。(2)在不同土壤细菌α-多样性分析中,亚高山草甸土(YGS)的Chao1、Observed Species、Shannon和Simpson指数均为最高,表明该土壤中细菌群落数量和多样性最高。(3)在不同土壤细菌β-多样性分析中,褐土(HT)、沼泽土(ZZT)、亚高山草甸土(YGS)以及风沙土(ST)相互高度重叠,表明该地区这4种土壤细菌群落结构组成相似,而草甸土(CD)土壤细菌群落具有显著差异(P<0.05)。(4)对不同生境的RDA冗余分析中,放线菌门与土壤pH呈正相关;变形菌门与土壤pH和全钾(TK)呈正相关;厚壁菌门与有机质(SOM)、全氮(TN)、全磷(TP)和含水量(MC)显著正相关。[结论]本研究揭示了若尔盖自然公园四川片区不同生境下土壤细菌群落组成结构的差异性和多样性,以及这些差异与环境因子的强相关性。该结果不仅有助于深化对土壤微生物生态学的理解,而且为土壤生态系统的管理提供了科学依据。

[Objective]The paper aimed to reveal the community structure and species diversity of soil bacteria in different habitats of the Si-chuan section of Zoige National Natural Park.[Method]The study employed high-throughput sequencing technology to study the diversity and community structure of soil bacteria in the soils from five dfferent habitats(subalpine meadow soil,cinnamon soils,bog soils,aeolian soils and meadow soils)in the Sichuan section of Zoige National Park and discussed the relationship between soil physicochemical properties and microbial community structure.[Result](i)Thetaxonomic analysisof soil bacteriarevealed theidentification of 36phyla,withthedomi-nant bacteria encompassing Actinobacteriota,Proteobacteria,Firmicutes,Acidobacteriota and Chloroflexi.(i)Inα-diversity analysis,sub-alpine meadow soils(YGS)showed the highest Chaol,Observed Species,Shannon and Simpson index,indicating the highest bacterial community richness and diversity in soil.(ii)Inβ-diversity analysis,the high overlap among cinnamon soils(HT),bog soils(ZZT),YGS and aeolian soils(ST)suggested a similar composition of bacterial communities among these four soil types in the region,while meadow soils(CD)bacteria community showed significant differences(P<0.05).(iv)In RDA redundancy analysis of different habitats,Acti-nobacteriota showed a positive correlation with soil pH;Proteobacteria showed a positive correlation with soil pH and total potassium(TK);Firmicutes showed significant positive correlations with soil organic matter(SOM),total nitrogen(TN),total phosphorus(TP)and mois-ture content(MC).[Conclusion]The research results reveal that the differences in the composition and diversity of soil bacterial communi-ties in different habitats of the Sichuan section of Zoige National Natural Park,as well as the strong correlation of these differences with envi-ronmental factors.The finding not only contributes to a deeper understanding of soil microbial ecology but also provides a scientific basis for the management of soil ecosystems.