School of Geography Science, Nanjing Normal University, Nanjing, China.
Jiangsu Provincial Key Laboratory of Materials Cycling and Pollution Control, Nanjing, China.
Environ Sci Pollut Res Int. 2020 Jun;27(17):21517-21532. doi: 10.1007/s11356-020-08629-z. Epub 2020 Apr 11.
Coastal wetland vegetation plays an important role in maintaining ecological function and is a key factor affecting the soil bacterial community. Spartina alterniflora was introduced to the Yancheng tidal marsh to stabilize the sediments and gradually replaced the native plants. However, the changes in the soil bacterial community profile caused by S. alterniflora invasion are poorly characterized. Here, we used MiSeq sequencing to compare the composition of the bacterial community in soil at different depths under exotic S. alterniflora (SA), native Phragmites australis (PA), and native Suaeda salsa (SS). The results showed that the pH value was lower, but the salinity, soil organic carbon, total nitrogen, and number of 16S rRNA genes were higher in SA soils than in PA and SS soils. Overall, Proteobacteria was the dominant bacterial phylum, followed by Chloroflexi, Acidobacteria, Planctomycetes, Gemmatimonadetes, and Nitrospirae. Anaerolineae in the Chloroflexi phylum showed the greatest difference based on vegetation, accounting for 14.4% of the overall bacterial community in SA soils but only about 3.8% of those in PA and SS soils. The composition, interaction, and predicted functional profiles of the bacterial community in SA soils were significantly different from those in PA and SS soils, especially for functions related to the sulfur and nitrogen cycles. Salinity was negatively correlated with the Shannon index and accounted for 37.7% of the total variation in the bacterial community, making it the most important environmental factor. Our results showed the differences in bacterial community composition among different vegetation types and soil depths in the Yancheng tidal marsh, which provides a microbial basis for a better understanding of the ecological functions in this ecosystem.
滨海湿地植被在维持生态功能方面发挥着重要作用，是影响土壤细菌群落的关键因素。互花米草（ Spartina alterniflora ）被引入盐城潮滩以稳定沉积物，并逐渐取代了本地植物。然而，互花米草入侵引起的土壤细菌群落组成的变化特征还知之甚少。在这里，我们使用 MiSeq 测序比较了不同深度下外来互花米草（ SA ）、本地芦苇（ PA ）和本地碱蓬（ SS ）土壤中细菌群落的组成。结果表明，SA 土壤的 pH 值较低，但盐度、土壤有机碳、总氮和 16S rRNA 基因数较高。总体而言，变形菌门是优势细菌门，其次是绿弯菌门、酸杆菌门、浮霉菌门、芽单胞菌门和硝化螺旋菌门。绿弯菌门中的 Anaerolineae 基于植被差异最大，在 SA 土壤中占整个细菌群落的 14.4%，而在 PA 和 SS 土壤中仅占约 3.8%。SA 土壤中细菌群落的组成、相互作用和预测功能谱与 PA 和 SS 土壤中的明显不同，特别是与硫和氮循环相关的功能。盐度与 Shannon 指数呈负相关，占细菌群落总变异的 37.7%，是最重要的环境因素。我们的研究结果表明，盐城潮滩不同植被类型和土壤深度的细菌群落组成存在差异，为更好地理解该生态系统的生态功能提供了微生物基础。
