东黄渤海11-12月有色溶解有机质的分布特征

Spatial distribution of colored dissolved organic matter (CDOM) in the Bohai, Yellow and East China Seas in November and December

采集了2016年11-12月期间东、黄、渤海表、中、底海水样品,分析了海水中溶解有机质的紫外-可见光吸收光谱特征,探讨了渤海和黄东海海域秋冬季有色溶解有机物(CDOM)的分布特征、来源和影响因素。结果表明:在渤海和黄东海,表、中、底层CDOM均呈现近岸高、远海低的分布特征,渤海CDOM含量高于黄东海。吸收系数a355和光谱斜率S275-295呈显著负相关。结合CDOM的a355分布和S275-295,表明CDOM受到陆源输入的显著影响。渤海海区黄河口海域由于黄河水的直接输入和在大风影响下黄河口的泥沙再悬浮作用,CDOM含量最高。12月渤海中心存在CDOM和DOC的低值区,位置和夏季渤海双中心冷水团一致。在黄东海海域,高盐度台湾暖流的导致了黄东海DOC低浓度区域的产生,但对CDOM的含量分布没有明显影响。在渤海和黄东海,CDOM和DOC无显著相关性。

UV-Vis spectral data was analyzed for the surface,middle,and bottom layer water samples of the Bohai Sea,Yellow Sea and East China Sea in November and December,2016.The distribution characteristics,sources and influencing factors of CDOM in the study area had been investigated.The results showed that CDOM concentrations in the Bohai Sea were higher than those in the Yellow Sea and the East China Sea.In these three Chinese marginal seas,the CDOM concentration showed a decreased trend from the nearshore to the open sea.Strong correlations were observed between value a355 and spectra slope S275-295.Considering the distribution patterns of a355 and S275-295,a dominant terrestrial source of CDOM was concluded.In the Bohai Sea,the highest concentration of CDOM was detected in the Yellow River estuary,due to the combining effects of the direct riverine discharge and sediment re-suspension by strong wave movement in winter.The lowest DOC and CDOM concentrations in the Bohai sea were observed in the regions,where the double-center cold-water mass areas occurred in the summer.The invasion of the Taiwan Warm Current,charactered by high salinity and low DOC,resulted in an obvious regional low value of DOC except for CDOM concentration.CDOM and DOC did not show remarkable correlation in the Bohai Sea,Yellow Sea and East China Sea.