冬季海南省东北部河流及近岸海区有机碳的分布特征

Distribution and composition of organic carbon in the northeastern Hainan rivers and coasts during winter

2006年12月在海南省东北部河流万泉河和文昌河以及周边的红树林和珊瑚礁体系采集水样,测定其溶解有机碳(DOC)和颗粒有机碳(POC)的含量。结果表明,万泉河水体中DOC和POC的平均浓度分别为139.3和39.7μmol·L-1;文昌河水体中DOC和POC的平均浓度则为133.0和47.4μmol·L-1,其周边红树林水体DOC和POC的平均浓度分别为214.1和27.9μmol·L-1;珊瑚礁周边水体DOC和POC的平均浓度分别为66.3和22.4μmol·L-1。文昌河周边的养殖活动及红树林水体对该河流中的高DOC和POC可能有显著贡献,且文昌河POC%与TSM浓度均呈显著负相关(R2=0.71,n=9)。万泉河、文昌河和珊瑚礁周边水体POC/Chla的比值分别介于72—312、43—196、122.5—334。估算浮游植物对万泉河、文昌河和珊瑚礁周边水体POC的贡献量分别为34%、45%、38%。

Water samples collected in the northeastern Hainan rivers and coasts in December 2006 were used to determine concentrations of dissolved organic carbon（DOC） and particulate organic carbon（POC）.During the observation period,the concentrations of DOC and POC in the Wanquan River were 139.3 and 39.7μmol·L-1,respectively,and were 133.0 and 47.4μmol·L-1,respectively in the Wenchang River.The DOC and POC concentrations in the adjacent mangrove waters were 214.1 and 27.9μmol·L-1,respectively,and in adjacent coral reef waters were 66.3 and 22.4μmol·L-1,respectively.Aquacultural activities and mangrove system near the Wenchang River could be the major sources for higher DOC observed in the river.There is an inverse relationship between the concentrations of total suspended matter（TSM） and POC% in the Wenchang River（R2=0.71,n=9）.The ratio of POC/Chl a was 72—312 in the Wanquan River,43—196 in the Wenchang River,and 122.5—334 in the adjacent coral reef waters.The contribution of phytoplankton to POC,estimated by a simple model,was 34% in the Wanquan River,45% in the Wenchang River,and 38% in the adjacent coral reef waters.