Distributions of carbon, nitrogen and phosphorus in the surface sediments and their ecological implications in the areas of Cold Water Mass and off the western coast of the Southern Yellow Sea
南黄海冷水团海域及西部近岸区表层沉积物中碳、氮、磷的分布特征及其生态学指示意义

Based on the data of sediment chemistry and other environmental factors, distributions of carbon, nitrogen and phosphorus in the surface sediments and the ecological implications were analyzed and discussed in the areas of Cold Water Mass and off the western coast of the Southern Yellow Sea. The results showed that the contents of moisture, TOC, TN, TP and N/P ratio in the surface sediments of the Cold Water Mass were higher than those off the western coast. TOC concentrations were significantly affected by the sediment type (grain size), material sources and sedimentary environment, and high TOC values occurred mainly in the muddy sediments. TN contents were significantly positively correlated with TOC contents in the surface sediments, indicating the similarity of TN and TOC sources. In contrast, TP contents were not significantly correlated with the contents of TN or TOC, reflecting the complex sources of TP. The significant differences of the sediment biogeochemical characteristics in the Cold Water Mass and the coastal areas indicated the different controlling factors for sediment chemistry. TOC and TN contents in the surface sediments of the Cold Water Mass were largely influenced by biological activities in the water column, whereas TN and TP in the surface sediments off the western coast was slightly impacted by the biological activities in the water column. The annual average DO concentrations posed some impacts on TOC and TN distributions in the surface sediments.