浙江近岸海域春季表层溶解氧饱和度分布及影响因素

Distribution and Main Influencing Factors of the Surface Dissolved Oxygen Saturation of Zhejiang Offshore in Spring

根据2014年春季对浙江省近岸海域溶解氧的调查结果,结合现场的温度和盐度,得出溶解氧饱和度的平面分布,并在此基础上探讨了饱和度与温度、盐度、化学需氧量、浮游植物丰度之间的关系。结果显示,浙江省近岸海域溶解氧饱和度范围为92.1%-120%,均值为100%。总体呈西部沿岸低,东部外海高的平面分布趋势。溶解氧饱和度高值区与浮游植物丰度的高值区一致。低饱和区域化学需氧量含量基本高于1 mg/L。陆源径流和有机物质耗氧分解是沿岸低饱和区域主要控制因素,外海水和浮游植物光合作用是高饱和区域主要控制因素。径流和外海水对有机物质分解和浮游植物光合作用有一定的调控作用。

According to the data collected in the 2014 Zhejiang offshore spring survey, the surface dissolved oxygen （DO） saturation distributions were analyzed. On this basis, the relationships between DO saturation and temperature, salinity, chemical oxygen demand （COD） and phytoplankton density were preliminarily explored. The results showed that： The Zhejiang offshore DO saturation was in the range of 92.1% to 120% , averaged at 100% , lower in coastal area and higher in outside area. The high values area of DO saturation is quite consistent with phytoplankton density. In the low DO saturation area,the COD concentrations are above 1 mg/L mostly. In the low DO saturation area,terrestrial runoff and organic matter oxidation are the main influencing factors. In the high DO saturation area,outer seawaters and phytoplankton photosynthesis are the dominant factors. Runoff and outer seawaters also have a certain regulating effect on organic matter oxidation and phytoplankton photosynthesis.