[Distribution characteristics of COD and DO and its influencing factors in the Daliaohe Estuary].
摘要
The concentrations of COD and DO were measured in the Daliaohe Estuary in April, July and November of 2010, and their distribution characteristics and influencing factors were discussed. The results showed that the concentrations of COD were 12.10, 4.42 and 4.38 mg · L(-1) in April, July and November of 2010, respectively. They were mainly influenced by rainfall, runoff and municipal sewage. COD values decreased with the increasing DO from the inner of Daliaohe Estuary to adjacent waters. Spatial distribution of COD was mainly controlled by agriculture and urban sewage and tides. The concentrations of DO were 8.46, 4.23 and 10.30 mg · L(-1) in April, July and November of 2010, respectively, and were mainly influenced by temperature and oxygen consumption of organic matter. Hypoxic zone was found in the low-salinity area in summer, which was mainly controlled by excessive emission of organic matter and nutrients in Yingkou, tidal effects and long residence time of water in the estuary.