毛乌素沙地臭柏(Sabina vulgaris)群落生物土壤结皮细菌群落组成及其影响因素  

Composition and influencing factors of the biological soil crust bacterial communities in the Sabina vulgaris community in Mu Us Sandy Land

作　　者：周虹 吴波[1,2] 高莹 成龙[1] 贾晓红[1,2] 庞营军[1] 赵河聚 Zhou Hong;Wu Bo;Gao Ying;Cheng Long;Jia Xiaohong;Pang Yingjun;Zhao Heju(Institute of Desertification Studies,Chinese Academy of Forestry,Beijing 100091,China;Key Laboratory of Desert Ecosystem and Global Change,Chinese Academy of Forestry,Beijing 100091,China)

机构地区：[1]中国林业科学研究院荒漠化研究所,北京100091 [2]中国林业科学研究院荒漠生态系统与全球变化重点实验室,北京100091

出　　处：《中国沙漠》2020年第5期130-141,共12页Journal of Desert Research

基　　金：国家重点研发计划项目(2016YFC0500806,2016YFC0500801);中国林业科学研究院荒漠化所结余资金(IDS2018JY-3,IDS2018JY-9)。

摘　　要：臭柏(Sabina vulgaris)是毛乌素沙地的主要固沙植物。臭柏群落中广泛分布的生物土壤结皮对维持沙地生态系统稳定具有重要意义。细菌是生物土壤结皮的重要组成部分,在维持生物土壤结皮结构和功能方面发挥着重要作用,但细菌群落组成及多样性随生物土壤结皮发育的变化尚不完全清楚。采用Illumina测序技术,分析了毛乌素沙地臭柏群落不同发育阶段生物土壤结皮(微生物结皮、藻结皮、地衣结皮和苔藓结皮)与裸沙的细菌群落组成及多样性,探究影响细菌群落结构的主要环境因子。结果表明:在毛乌素沙地随生物土壤结皮发育,细菌群落的多样性显著增加(P<0.05),苔藓结皮细菌群落多样性最高。生物土壤结皮的细菌群落以变形菌门(Proteobacteria)、放线菌门(Actinobacteria)、蓝藻门(Cyanobacteria)和酸杆菌门(Acidobacteria)为优势菌群,这4个门的相对丰度均占各发育阶段生物土壤结皮细菌总丰度的78%以上。随生物土壤结皮发育,细菌群落组成发生显著变化,抗逆性较强的寡营养类群,如厚壁菌门(Firmicutes)和变形菌门(Proteobacteria)的相对丰度逐渐降低(P<0.05);富营养类群,如放线菌门(Actinobacteria)、酸杆菌门(Acidobacteria)、拟杆菌门(Bacteroidetes)和绿弯菌门(Chloroflexi)的相对丰度逐渐增加(P<0.05);蓝藻门(Cyanobacteria)在藻结皮阶段的相对丰度显著高于其他发育阶段(P<0.05)。群落组成的变化预示着生物土壤结皮细菌群落的生态功能由结皮发育初期通过促进土壤颗粒胶结来增加土壤表面的稳定性,转变为结皮发育后期通过固定碳氮和凋落物分解来促进生态系统的物质循环。细菌群落是生物土壤结皮发育过程中水分和养分变化的敏感指标,结皮层含水量、全碳、有机碳、全氮、硝态氮和全磷含量是促使生物土壤结皮细菌群落组成发生变化的主要环境因子。Sabina vulgaris is the dominant sand-binding shrub species in the Mu Us Sandy Land. The widely distributed biological soil crusts(BSCs)in Sabina vulgaris community are of great significance to maintain the stability of desert ecosystem. Bacteria are an important part and play important roles in maintaining the structure and function of BSCs. However,the changes of diversity and composition of the bacterial communities with the development of BSCs are not fully understood. In this study,Illumina sequencing was used to analyze bacterial communities’ diversity and composition of four different developmental stages of BSCs(microbial,algae,lichen and moss crusts)and bare sand in Sabina vulgaris community in the Mu Us Sandy Land,and to explore the main environmental factors influencing bacterial community structure. Results showed that in the Mu Us Sandy Land,the diversity of bacterial communities significantly increased with the development of BSCs(P<0. 05),and reached the highest value in the moss crusts. Bacterial communities of BSCs were dominated by the phyla of Proteobacteria,Actinobacteria,Cyanobacteria and Acidobacteria,as their relative abundance accounted for more than 78% of the total bacterial abundance in different developmental stages of BSCs. Bacterial community compositions significantly changed with the development of BSCs. In particular,the relative abundance of Proteobacteria and Firmicutes,which belonged to the oligotrophic bacteria in stress resistance,significantly decreased from bare sand to moss crusts,whereas the relative abundance of Actinobacteria,Acidobacteria,Bacteroidetes and Chloroflexi,which belonged to the eutrophic bacteria,significantly increased. The relative abundance of Cyanobacteria in algae crusts was significantly higher than that in other developmental stages(P<0. 05). The change of bacterial community composition indicated that the community ecological function changed with the development of BSCs,from increasing the stability of soil surface by promoting soil particle cemen

关 键 词：生物土壤结皮 发育过程 细菌群落 Illumina测序 毛乌素沙地 

分 类 号：Q938.1[生物学—微生物学]