Indicatory bacteria and chemical composition related to sulfur distribution in the river-lake systems

Sulfate related water quality and trophic status are crucial to operation of water diversion. Though the sulfur geochemistry in the lake sediment have well studied, the effective indicator of surrounding environment conditions related to sulfur in river-lake systems are still unknown. In this study, Dongping Lake (DPH), Weishan Lake (WSH), and Hanzhuang trunk canal (HZQ) were selected as the typical river-lake systems in the eastern of China. Different spatial variations in sedimentary sulfate, total sulfur, and elemental composition of sediments were investigated in these areas. The relatively high sulfate in surface water and sediments appeared in portions of WSH. The biodiversity of HZQ and WSH surface sediments was much higher than that of DPH. Pseudomonas, Acinetobacter, and Thiobacillus were the dominant genera of the river-lake systems. Among the different genera in distribution, genera such as Malikia, Sulfurovum and Lysinibacillus were significantly negatively correlated with sulfur related environmental factors. While the genera such as Pseudomonas, Vogesella and Acinetobacter were significantly positively correlated with these factors. Compared with connectivity in the largest interaction network, bacteria such as Proteus, Acidobacter and Chlorobacteria were identified as indicatory taxa to infer sulfate related conditions in the river-lake systems.

硫酸盐相关水质与营养状态对调水工程的运行至关重要。尽管湖泊沉积物中的硫地球化学过程已得到充分研究，但河湖系统中与硫相关的周边环境有效指示因子仍不明晰。本研究选取中国东部典型河湖系统——东平湖（DPH）、微山湖（WSH）与韩庄干渠（HZQ）作为研究对象，对上述区域沉积物中的沉积硫酸盐、总硫及元素组成的空间分异特征展开了调查。微山湖部分区域的地表水与沉积物中硫酸盐含量相对较高。韩庄干渠与微山湖表层沉积物的生物多样性显著高于东平湖。假单胞菌属（Pseudomonas）、不动杆菌属（Acinetobacter）、硫杆菌属（Thiobacillus）为该河湖系统的优势菌属。在分布存在差异的菌属中，马里克氏菌属（Malikia）、硫还原杆菌属（Sulfurovum）、赖氨酸芽孢杆菌属（Lysinibacillus）等与硫相关环境因子呈显著负相关；而假单胞菌属（Pseudomonas）、沃斯氏菌属（Vogesella）、不动杆菌属（Acinetobacter）等则与上述因子呈显著正相关。与最大互作网络的连通性特征相比，变形杆菌属（Proteus）、酸杆菌属（Acidobacter）及绿菌门（Chlorobacteria）等被鉴定为可用于推断河湖系统硫酸盐相关环境状态的指示类群。