南海大鹏湾盐田海域骨条藻数量的多元分析

MULTIVARIABLE ANALYSIS OF SKELETONEMA COSTATUM QUANTITY IN YANTIAN, DAPENG BAY, THE SOUTH CHINA SEA

1990年及1991年3月30日一5月30日，在南海大鹏湾盐田海域设点测定骨条藻数量及各环境要素，以逐步回归、主成分分析及判别分析的方法，分析该海区骨条藻数量与环境因子的关系。结果表明，骨条藻数量与环境因子中的DO，Chl．c，Si（OH）4，PO4，N的关系密切；1990年4，5月与1991年4，5月骨条藻数量差异与该期间环境因子值差异显著有关;初步提出用三维主成分分析图及判别分析方程作为盐田海域骨条藻赤潮预报的方法。

Skeletonema costatums quantity and environmental factors were measuredin Yanian Dapeng Bay during Mar. 30th to May 30th in 1990 and 1991,respectively. The relation between them in the Yantian sea area was studied bymultivariable statistical analysis, stepwise regression analysis, principal component analysis and discrindnant analysis. The following stepwise regression equations were obtained.Stepwise regression equations of S. costatuof s quantity to environmefltal factorsin 1990:Y=940.90-130.02XDo+ 6.96Xchl.c -4.94XNO3+0.13Xsi(oH)4, n=60, R=0. 382Stepwise regression equation of S costatum s quantity to environmental factorsin 1991:Stepwise regression equation of S. costatuof s quantity to environmental factorsin 1990, 1991:Stepwise regression equation of S costatnd s qualltity to envirotunental factorsin 1990, 1991 (when the ntunber of S costatum more than 8×108cell /m3): ( Sighficant at 0.05 level, Siedficant at 0.01 level)The results show that, the qualltity of S costatum was higlily correlated with theDo, Chl. c, Si (OH)4, PO4, N concentrations. The difference between S costatam squantity obtained from Apr. to May in l99O and 1991 was closely connected with thesighficat differences of their environmelltal factors in those two periods oftime. TWo tentative predictive models of S costatuof s blooms in these sea area waters were suggested by using three dimensiona principal components map anddiscrindnantal equation.