南黄海有色可溶有机物日变化分析

Diurnal variation of colored dissolved organic matter in the South Yellow Sea

用高时间分辨率的韩国静止海洋水色仪(GOCI)影像,分析了2015年10月2日及2016年9月22日南黄海有色可溶有机物(CDOM)的时空分布特征及影响因素。结果表明,南黄海近岸CDOM浓度高于中央海域,江苏沿岸含量最高;近岸水体以陆源输入为主,远岸水体以微生物现场生产为主。结合叶绿素(chl-a)浓度采样数据分析发现,CDOM日变化时间、空间特征与chl-a日变化一致,回归分析的R2高于0.88,验证了二者时空变化的正相关关系。在深水区,CDOM随悬浮物浓度增加而增加,且线性趋势明显。与提取的潮汐、潮流数据的对比分析发现,潮流是近岸水体(山东半岛南岸与江苏沿岸)表层CDOM变化的主要动力因素。

The temporal-spatial distribution of the colored dissolved organic matter （ to it in the South Yellow Sea on October 2,2015 and September 22,2016 were CDOM） and the influencing factors analyzed based on the high temporal resolution images of Geostationary Ocean Color Imager （GOCI）. The analyzing results indicate that the CDOM concentration in the nearshore area is higher than that of the central area of the sea, and the maximum value is located in the coastal area of Jiangsu Province. The nearshore water is dominated by terrestrial input, while offshore water is mainly dominated by microbial production. Given the existence of oceanic fronts, the boundary between areas with high value and low value range is obvious. The temporal and spatial characters of CDOM are found to coincide with that of chlorophyll-a. The regression analysis shows that the fitting coefficient is higher than 0.88, which verifies the positive correlation between CDOM and chlorophyll-a. In deep water, CDOM increases with total suspended matter, of which the linear trend is significant. A contrastive analysis of tide and tidal current finds that tide-driven sub-surface water substance changes little on surface CDOM. Tidal current is a main dynamic factor of CDOM varia- tion in coastal waters （Shandong peninsula south coast and Jiangsu coast）.