College of Environmental Science and Engineering, Ocean University of China, Qingdao 266100, China.
College of Environmental Science and Engineering, Ocean University of China, Qingdao 266100, China; Key Laboratory of Marine Environmental Science and Ecology, Ministry of Education, Ocean University of China, Qingdao 266100, China.
Mar Environ Res. 2023 Sep;190:106102. doi: 10.1016/j.marenvres.2023.106102. Epub 2023 Jul 27.
To address the complex biogeochemical processes and potential function of dissolved organic matter (DOM) in estuaries before it enters the sea, water samples were collected seasonally in a dozen Laizhou Bay estuaries and in the Yellow River estuary, North China. The results showed that chromophoric dissolved organic matter (CDOM) varied in abundance but had consistent spectral slopes at the same sampling time. Gradually, CDOM decreased while spectral slopes increased from freshwater to seawater. The spectral slope of CDOM varied temporally (higher in October and lower in August) more than it varied spatially. The fluorescent components and biological indices of CDOM indicated that in situ biological activities were the dominant sources in the waters examined in this study. The CDOM was generally more variable than the dissolved organic carbon (DOC) in most of the estuaries. However, marine CDOM may obviously increase in estuaries when indirectly stimulated by rapidly decomposing terrestrial DOM.
为了研究在进入海洋之前，河口内溶解有机物质（DOM）的复杂生物地球化学过程和潜在功能，本研究在十几个莱州湾河口和中国北方的黄河口进行了季节性的水样采集。结果表明，发色溶解有机物质（CDOM）的丰度不同，但在同一采样时间具有一致的光谱斜率。从淡水到海水，CDOM 逐渐减少，而光谱斜率增加。CDOM 的光谱斜率在时间上变化较大（10 月较高，8 月较低），空间变化较小。CDOM 的荧光成分和生物指标表明，在本研究中所检测的水域中，原位生物活性是其主要来源。在大多数河口，CDOM 的变化通常比溶解有机碳（DOC）更为明显。然而，当受到快速分解的陆源 DOM 的间接刺激时，海洋 CDOM 可能会在河口明显增加。
