条子泥垦区养殖尾水净化河道的细菌群落结构及其与环境因子的关系

监测条子泥垦区养殖尾水净化河道内的水体和沉积物,以探究河道内的细菌群落结构及与环境因子的关系。结果表明,河道内水质在不同月份间的差异显著,沉积物的理化性质在不同位点间的差异显著。依总氮(TN)和总磷(TP)判断,河道水体处于富营养化水平,但满足江苏省池塘养殖尾水排放二级标准。碳酸氢钠可提取磷(Olsen-P)表明沉积物不处于高营养水平。水体和沉积物中细菌群落组成的变化同理化性质一致,两环境中细菌群落的多样性、丰富度和组成均存在显著差异。蓝细菌门(Cyanobacteria)是水中的优势菌门之一,在9月份水体中的相对丰度高达39.33%。蓝细菌属(Cyanobium_PCC-6307)在水体(13.34%)和沉积物(8.15%)中均占据最高丰度,对细菌群落的影响最大。水体中水温(T)、TN、可溶性活性磷酸盐(SRP)和高锰酸盐指数(COD_Mn)与细菌群落显著相关(P<0.05)。除TN外,其余3项指标均与蓝细菌属呈正相关。沉积物中水溶性磷(WSP)、易解析磷(RDP)和总碳(TC)与细菌群落显著相关,WSP和RDP与蓝细菌属呈正相关。应加强对养殖尾水中磷的控制,以限制蓝细菌属在河道中的富集。本研究为沿海垦区水产养殖的尾水调控和健康发展提供了参考。

Bacterial community structure and its relationship with environmental factors in the purification channel of aquaculture Tailwater in Tiaozini Reclamation Area

To explore the bacterial community structure and its relationship with environmental factors, the water and sediment in the purification channel of aquaculture tailwater in the Tiaozini reclamation area were monitored. The results showed that there were significant differences in water quality between different months and physicochemical properties of sediments at different sites. Judging by the total nitrogen (TN) and total phosphorus (TP), the river water was at a level of eutrophication, but it met the second-level discharge standard of water from aquaculture ponds in Jiangsu Province. Olsen-P indicated that the sediments were not at a high nutrient level. The changes of bacterial community composition in water and sediments were consistent with physicochemical properties, and significant differences were found in the diversity, richness, and composition of bacterial communities in the two environments. Cyanobacteria was one of the dominant bacteria in water, with a relative abundance of 39.33% in September. Cyanobium_PCC-6307 occupied the highest abundance in both water (13.34%) and sediments (8.15%) and had the greatest effect on bacterial communities. Water temperature (T), TN, soluble active phosphate (SRP), and permanganate index (COD_Mn) were significantly correlated with bacterial communities. Except TN, the other 3 indicators were positively correlated with Cyanobium_PCC-6307. Water soluble phosphorus (WSP), readily desorbable phosphate (RDP), and total carbon (TC) in the sediments were significantly correlated with bacterial communities, and WSP and RDP were positively correlated with Cyanobium_PCC-6307. To limit the accumulation of Cyanobium_PCC-6307 in the channels, the control of phosphorus in aquaculture tailwater should be strengthened. This study provides a reference for the regulation of tailwater and healthy development of aquaculture in coastal reclamation areas.