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根据南沙群岛海区５个沉积柱样和大量表层样的分析资料讨论了有机碳的沉积作用。深海有机碳含量一般为０．２％－１．３％。水柱深度对其分布的控制作用不明显。分析结果发现冰期、间冰期，尤其是本次冰期有机碳含量变化明显，４个柱样晚第四纪的质量堆积速率在末次冰期时最大。有机碳保存的主要控制因素是溶解氧浓度、粘土矿物含量、水柱深度和底栖混合强度，其中溶解氧浓度是最重要因素。底栖有孔虫的相对丰度，如Ｕｖｉｇｅｒｉｎａ和Ｂｕｌｉｍｉ－ｎａ，可用来指示溶解氧和有机碳含量。有机碳含量与海洋生产力关系极为密切，它可用来重建海洋古生产力的长期变化。采用Ｍｌｌｅｒ和Ｓｕｅｓｓ方程以及Ｓａｒｎｔｈｅｉｎ方程的计算结果与目前生产力值结果比较表明，后一种方法因充分考虑了溶解氧浓度和水柱深度而更接近现代值。
The deposition of organic carbon was discussed based on five sedimentary column samples and a large number of surface layer-like data from the Nansha Islands. Deep-sea organic carbon content is generally 0.2% -1.3%. The effect of depth of water on its distribution is insignificant. The results show that there are obvious changes in organic carbon content in glacial, interglacial, and especially during this glacial period. The mass accumulation rate of the four column late Quaternary is the largest in the last glacial period. The main controlling factors of organic carbon storage are dissolved oxygen concentration, clay mineral content, water column depth and benthic mixed intensity, of which dissolved oxygen concentration is the most important factor. The relative abundance of benthic foraminifera, such as Uvigerina and Bulimi-na, can be used to indicate dissolved oxygen and organic carbon content. The organic carbon content is very closely linked with the productivity of the oceans and it can be used to reconstruct the long-term changes in paleocapacity of the oceans. Comparisons of the Mller and Suess equations and the Sarnthein equation with the current productivity results show that the latter approach is closer to modern values due to full consideration of dissolved oxygen concentration and depth of water column.