珠江口水体有机碳的季节性变化

发布时间：2018-05-10 19:54

  本文选题：颗粒有机碳 + 溶解有机碳　； 参考：《热带海洋学报》2016年04期

【摘要】：调查了珠江口不同季节颗粒有机碳(particulate organic carbon,POC)和溶解有机碳(dissolved organic carbon,DOC)含量的分布特征,结合碳氮比值(C/N)、叶绿素a(Chl a)含量、溶解氧(dissolved oxygen,DO)含量等水化学参数,探讨了珠江口POC、DOC来源、输送方式及混合行为的季节变化。结果表明,珠江口水体POC可能主要受到水体自生浮游植物有机碳输入的影响,DOC可能主要来自于河流输送的陆源有机碳。在降雨量较大的5月份,POC来自自生浮游植物有机碳的贡献相对减小。降雨量同样较大的8月份DOC来自河流输送的陆源有机碳的贡献增加。不同季节珠江口水体总有机碳中的DOC一直高于POC。珠江口POC、DOC含量受到淡水与海水混合进程的影响,淡水与海水的混合效应可能是从出虎门进入伶仃洋的低盐度区(盐度1‰~5‰的水体)开始延伸至外海。微生物的降解作用可能对POC和DOC在出虎门之前的下降趋势产生了重要影响,而微生物对新鲜的浮游植物有机碳的利用、以及浮游植物生产量的降低和颗粒物絮凝沉降作用则可能是POC在出虎门后下降幅度大于DOC的重要原因。
[Abstract]:The distribution characteristics of particulate organic (POC) and dissolved organic carbon (organic) contents in different seasons in the Pearl River Estuary were investigated. The source of POC in the Pearl River Estuary was discussed by combining the C / N ratio (C / N), the content of chlorophyll a(Chl a (chlorophyll a(Chl a) and the content of dissolved oxygen (a(Chl). Seasonal variation of transport mode and mixing behavior. The results show that the POC in the Pearl River Estuary may be mainly affected by the organic carbon input from the phytoplankton. In May, the contribution of POC from autophytoplankton was relatively reduced. Similarly heavy rainfall increased the contribution of DOC from land-based organic carbon transported by rivers in August. The DOC of total organic carbon in the Pearl River Estuary was higher than that in the Pearl River Estuary in different seasons. The DOC content of POC in Pearl River Estuary is affected by the mixing process of fresh water and sea water. The mixing effect of fresh water and seawater may extend from the low salinity area (1 鈥，

本文编号：1870649