黄河三角洲滨海湿地生态修复区春季土壤古菌和细菌群落结构探究

Study on the soil archaea and bacterial community structure in ecological restoration area of Yellow River Delta coastal wetland in spring

盐地碱蓬是黄河三角洲滨海湿地生态功能的起点和核心,其原生修复在土壤改良和微生物功能恢复方面的作用仍未可知。因此,本研究开展了盐地碱蓬修复土壤的细菌和古菌群落结构分析,借助理化性质检测和高通量手段进行了样品实验室检测。结果发现,滨海湿地土壤均呈碱性(pH=7.92~8.45),盐度含量较高(>30.98‰)且非植被区土壤有明显的结晶盐(>45.26‰)。细菌方面,岸边碱蓬以Muribaculaceae(14.81%)和Helicobacter(8.00%)为主,盐土碱蓬以Marinobacter(20.19%)和Halomonas(7.15%)为主,核心修复土壤以Muribaculaceae(9.37%)、Inhella(8.61%)和Halanaerobium(8.25%)为主;非植被覆盖的高盐土、近岸河边与河边过渡区主要以Marinobacter(5.75%~17.91%)、Halomonas(9.01%~10.92%)、Muribaculaceae(5.91%~10.26%)为主;植被覆盖导致细菌Shannon指数差异显著(P=0.05)。古菌方面,植被区主要以Salinigranum(10.00%~34.17%)、Halorubrum(12.1%~29.33%)和Halogranum(1.42%~7.70%)为主;非植被区主要以Halolamina(6.97%~20.25%)、Halogranum(2.06%~26.86%)和Halorubrum(12.54%~21.54%)为主。借助CCA、PCoA、韦恩图和功能预测发现,盐地碱蓬定植导致细菌(22.6%)、古菌(29.5%)组成存在差异,盐分是导致差异的重要原因之一。植被根植后菌群更加多样且元素循环出现,非植被区中微生物组成相近但存在潜在竞争。所以,植被修复能有效实现土壤生态功能恢复,而修复前的土壤中微生物却为污染物降解和抗菌素开发提供了种质资源。

The Suaeda salsa is the starting point and core for ecological function of coastal wetland in Yellow River Delta,while the role of their in-situ remediation in soil reclamation and microbial function recovery is still unknown.Therefore,the analysis for bacterial and archaea community structure of soil restored by Suaeda salsa were carried out in this study,among which the samples were tested in laboratory by physical and chemical properties detection and high throughput methods.The results showed that all the coastal wetland soil samples were alkaline with pH of 7.92-8.45and high salinity(>30.98‰),and the soil in unvegetated area possessed obvious crystalline salts(>45.26‰).In terms of bacteria,Muribaculaceae(14.81%)and Helicobacter(8.00%)were the main species of shoreside suaeda.Marinobacter(20.19%)and Halomonas(7.15%)were the main species of Suaeda salsa,among which Muribaculaceae(9.37%),Inhella(8.61%)and Halanaerobium(8.25%)dominated in the riverside vegetation zone(RG).The Marinobacter(5.75%-17.91%),Halomonas(9.01%-10.92%)and Muribaculaceae(5.91%-10.26%)were the main bacteria in high saline soil zone,riverside and transition zone without vegetation.There was a significant difference in the Shannon index(P=0.05)between vegetation and non-vegetation areas in bacteria.In terms of archaea,Salinigranum(10.00%-34.17%),Halorubrum(12.1%-29.33%)and Halogranum(1.42%-7.70%)were the predominant species in vegetation areas.And Halolamina(6.97%-20.25%),Halogranum(2.06%-26.86%)and Halorubrum(12.54%-21.54%)were widespread in non-vegetation areas.Based on CCA,PCoA,Venn diagram and functional prediction,it was found that the composition of bacteria(22.6%)and archaea(29.5%)were different between the rooted and unrooted soils caused by Suaeda salsa plantation.Besides,salinity also gave rise to this difference.After vegetation plantation,the flora was more diverse and element cycling appeared.The composition of microorganisms in non-vegetation areas was similar while there was potential competition.As a result,vegetation recultivation could effectively restore soil ecological functions,while the microorganisms in soil before restoration provided germplasm resources for pollutant degradation and antibiotic development.