渭河流域水体细菌群落的环境响应及生态功能预测

流域水体中细菌群落多样性及其代谢功能研究对流域水污染整治及生态修复和水体健康评价具有重要价值.基于Illumina MiSeq高通量测序技术研究渭河流域陕西境内综合治理后水体中细菌群落分布特性,利用冗余分析(redundancy analysis,RDA)方法分析了水体细菌群落与水环境因子的相关关系,并采用PICRUSt (phylogenetic investigation of communities by reconstruction of unobserved states)方法预测和评价了渭河流域细菌群落生态功能.研究结果显示,变形菌门、放线细菌门、蓝藻门和拟杆菌门细菌是水体细菌群落中的主要菌门,占整个细菌群落的相对丰度高达85%,这类细菌与水体中的TP、NO_2~--N、NO_3~--N和TN呈显著的正相关关系(P=0. 02 0. 05);灞河入渭口下游(S5)细菌群落丰度最高,皂河(S4)细菌群落丰度最低;渭河流域水体致使人类患传染性疾病的可能性较大,且对生物体内分泌系统有较大的影响.本研究成果可为渭河流域水环境健康有序发展提供理论基础.

Environmental Response and Ecological Function Prediction of Aquatic Bacterial Communities in the Weihe River Basin

The diversity of bacterial communities and their metabolic function in the waters of the Weihe River Basin are of great significance for water pollution remediation, ecological restoration, and water quality assessment. Illumina MiSeq high-throughput sequencing technology was applied to study the bacterial community distribution characteristics after the comprehensive treatment of the Shaanxi part of the Weihe River Basin. Furthermore, the correlation between the bacterial communities and environmental factors was analyzed by redundancy analysis (RDA), and the PICRUSt method was adopted to evaluate the ecological function of the bacterial communities. The results showed that Proteobacteria, Actinobacteria, Cyanobacteria, and Bacteroidetes were the main bacterial communities in the water, accounting for 85% of the total microbial community. Additionally, these bacteria showed a significant positive correlation (P=0.02, <0.05) with the TP, NO₂^--N, NO₃^--N, and TN. The bacteria community richness of water samples collected in Zaohe River was the lowest of all samples, while which in the downstream of the junction of Bahe river and Weihe river was the highest. In addition, water in the Weihe River Basin had great impact on the endocrine systems of aquatic organisms, and also had a possibility of infectious diseases for humans. Our research provides a theoretical basis for the safe and sustainable development of the water environment in the Weihe River Basin.