城市内河强还原性沉积物耗氧及相关因素研究

2009年7—8月间选择浙江省宁波市4条污染程度不同的内河，采集沉积物和水质样品. 采用自制的多管、多电极沉积物耗氧研究装置测得沉积物耗氧(SOD)值高达13.8～9.4×104 mg/(m2·h)，其中张桂河路林市场段(ST2站)SOD为87.0 mg/(kg·h)；同时测定了各站水质、沉积物理化指标. 结果表明:水体水温和沉积物w(氨氮)与SOD有较高的相关性，而有机质、底层ρ(DO)和ρ(COD_Cr)与SOD的相关性较差.表观污染严重的站位其沉积物表现出强烈的“瞬时耗氧”现象，这很可能是造成水体缺氧的主要原因之一. 

Research on Sediment Oxygen Demand and Related Factors for Strong Reductive Sediments in Urban River

Water and sediment samples were collected from urban rivers of four different pollution levels in the city of Ningbo during July to August, 2009. SOD (sediment oxygen demand) for each sample was tested using a homemade SOD device equipped with multi-electrodes and tubes. Water quality and physical-chemical index of the sediments from all stations were also analyzed. The SOD per area unit were between 13.8 mg/(m2·h) and 9.4×104 mg/(m2·h), and SOD per mass unit was 87.0 mg/(kg·h) in Station 2 (ST2). It was clearly shown that there was a significant correlation between water temperature and the concentration of ammonia nitrogen in the sediment with SOD. However, there was no significant correlation between organic matter, DO (dissolved oxygen) and COD_in in bottom-layer water with SOD. It was found that sediments from apparently heavily polluted stations appeared to have a strong “instantaneous oxygen consumption” phenomenon, which might be one of the main factors causing anoxia in the waters.