森林母土异地迁播后的土壤真菌和细菌变化

【背景】森林土壤中携带了大量种子和微生物,已经被广泛用于各种退化生态系统的植被恢复。但是,关于土壤迁播到退化生态系统后的真菌和细菌群落变化研究较少。【目的】研究土壤迁播后真菌和细菌的组成和多样性,比对其与森林母土和受体土壤之间的物种组成与群落差异。【方法】通过Illumina HiSeq高通量测序,获取迁播15个月的土壤、森林母土及受体土壤中真菌和细菌特征值,比对其多样性和丰富度。【结果】3类样地真菌优势菌门为担子菌门和子囊菌门,细菌优势菌门为酸杆菌门、变形菌门、放线菌门和绿弯菌门,土壤迁播后显著改变了真菌和细菌优势菌门的相对丰度。主成分分析表明3类样地真菌和细菌群落组成存在显著差异。聚类分析表明迁播土壤与受体土壤聚类距离更近,物种组成更相似,真菌和细菌优势属与受体土壤无显著差异。迁播土壤的真菌和细菌丰富度和多样性与森林母土差异显著(P0.05)。【结论】森林土壤迁播15月后,其细菌和真菌物种组成逐步趋同于受体土壤。该结果为进一步研究石漠化微生物生态系统、改善和提升土壤迁播技术提供支撑。

Changes of soil fungi and bacteria after forest mother soil transplantation

Background] Forest topsoil transplantation has been widely used in the restoration of degraded ecosystems because it carries a large number of seed banks and microbial communities. However, there are few studies had been carried out on the changes of fungi and bacteria communities after soil transplantation. Objective] This study compared the composition and diversity of fungi and bacteria of transplanted soil to its mother soil and receptor soil. Methods] Using Illumina HiSeq high-throughput sequencing technology, the characteristics of fungi and bacteria of mother soil, 15 months of transplanted soil and receptor soil were obtained, and their diversity and richness were compared. Results] Basidiomycota and Ascomycota were the dominant fungi in the three soil types; Acidobacteria, Proteobacteria, Actinobacteria and Chloroflexi were the dominant bacteria, the relative abundance of dominant fungi and bacteria changed significantly after soil transplantion. PCA analysis showed that there were significant differences in community structure of fungi and bacteria among the three soil types. UPGMA analysis showed that the distance between the transplanted soil and the receptor soil was closer, the species composition of the transplanted soil was more similar to the receptor soil, and there was no significant difference between the dominant genera of fungi and bacteria in the transplanted soil and the receptor soil. After transplantion, the abundance and diversity of fungi and bacteria were significantly different from its mother soil. Conclusion] The composition and diversity of bacteria and fungi of transplanted soil turned toward the receptor soil after 15 months. The findings provide a theoretical reference for further study of microbial ecosystem on rocky desertification environment, and provide a scientific base for the improvement of soil translocation technology.