基于PCA法的春、夏季东山湾海域富营养化特征

根据2011年5月和8月东山湾及邻近海域的调查结果,选择10个与富营养化有关的参数,包括溶解无机氮(DIN)、溶解硅酸盐(DSi)、活性磷酸盐(SRP)、总氮(TN)、总磷(TP)、化学耗氧量(COD)、溶解有机碳(DOC)、总有机碳(TOC)、叶绿素a(Chl-a)和浮游植物丰富度(d)等,应用主成分分析(PCA)法对该海域富营养化特征进行研究。主成分分析表明,主成分1(PC1)表征了有机污染、浮游植物和总磷状况;主成分2(PC2)反映了硅和氮营养水平,主成分3(PC3)体现了SRP的特点。春、夏季PC1、PC2、PC3和综合主成分(CPC)的空间分布表明漳江口和八尺门养殖区邻近海域富营养化风险较高;各主成分与盐度的相关分析表明东山湾内富营养化压力主要来自漳江,夏季有所增强;有机污染物和浮游植物可能是控制东山湾海域春、夏季富营养空间分布的主要驱动因素。

Analysis of eutrophication characteristics in Dongshan Bay based on PCA

According to the investigation results of Dongshan Bay and its adjacent sea area in May and August 2011, DIN、DSi、SRP、TN、TP、COD、DOC、TOC、Chl-a and total abundance of phytoplankton associated with eutrophication were analyzed with principal component analysis(PCA).Three principal components (PCs) were extracted with principal component analysis: phytoplankton、TP and COD for PC1, N nutrients and silicon nutrients for PC2 and P nutrients for PC3. Distribution of PC1、PC2、PC3 and CPC in spring and summer show the high eutrophication risk regions, where were Zhangjiang Estuary and Bachimen adjacent areas. The correlation analysis with salinity showed that eutrophication pressure was mainly from Zhangjiang in Dongshan Bay, and enhanced in summer. COD and phytoplankton are dominating factors in assessing the variation of eutrophication in Dongshan Bay and its adjacent area.