Response of soil bacterial community structure and function under two salt-tolerant plants in a coastal saline soil area of eastern Hebei province of China

Novelty statement This study investigated the changes of soil bacterial alpha-diversity and community structures in coastal saline soil after planting the medicinal and edible plants coastal feicai (Sedum aizoon L.)and dandelion "Binpu No. 1" (Taraxacum mongolicum Hand.-Mazz.). It also identified the biomarkers and differential metabolic functions of soils among different plots. Our findings revealed that planting S. aizoon and T. mongolicum significantly improved bacterial diversity, and altered composition and metabolic function in coastal saline soils. This study makes a significant contribution to the literature because it offers an insight into novel strategies for vegetation restoration and ecological reconstruction of saline soils. The plants Feicai (Sedum aizoon L.) and dandelion(Taraxacum mongolicum Hand.-Mazz.) have good salt tolerance, and can improve soil quality and the micro-ecological environment. Coastal saline-soil plots planted with S. aizoon and T. mongolicum and bare plots were used to explore their effects on the microbial community structure of coastal saline soil. The diversity and function of soil bacterial communities were analyzed using Illumina MiSeq high-throughput sequencing technology. The results showed that the alpha-diversity of soil bacterial communities were higher in planted than in bare plots, in the following order: T. mongolicum plot > S. aizoon plot > bare plot. The soil bacterial communities also changed after planting S. aizoon and T. mongolicum. The LDA effect size analysis showed that there were 37 indicator species among the three plot types. Correlation analysis of environmental factors showed that EC, AP, and OM were the main factors influencing bacterial community composition in this coastal saline soil. The PICRUSt functional prediction showed that the numbers of metabolic functions of bacterial communities were in the following order: T. mongolicum plot > S. aizoon plot > bare plot. The results provide a theoretical basis and plant species for developing salt-tolerant bacterial resources and phytoremediation of coastal saline soil.