东海磷营养盐变动影响因子分析

采用“有进有出”逐步回归等方法分析了影响东海磷营养盐变动的各环境因子的显著性及其影响权重,得到对东海磷营养盐变动起显著性影响的环境因子的相对重要性依次为:硅酸盐>硝酸盐>温度>溶解氧>亚硝酸盐>pH>盐度>碱度>氨,影响权重系数分别为18.01％、17.84％、15.17％、10.98％、8.43％、7.9％、7.63％、7.53％、6.52％;硅酸盐对磷营养盐变动显著性影响最大,表明东海磷、硅等营养盐的结构变化在浮游植物群落演变过程中起着重要作用,这与该海域近岸赤潮生物逐渐由中型(硅藻种类多)向小型和微型(甲藻种类多)发展的事实相符合。在构建东海磷营养盐动力学模型和海洋生态模型中时,必须对硅酸盐等环境因子予以充分考虑。

Analysis of influencing factors on phosphorus nutrient variation in the East China Sea

The "in-out" stepwise regression method is adopted to analyze the significance of environmental factors having influence on phosphorus nutrient variation and their influencing weights in the East China Sea. The results showed that the relative importance of environment factors influencing phosphorus nutrient variation in the East China Sea is as follows: silicate > nitrate > temperature > dissolved oxygen > nitrite > pH > salinity > basicity > ammonia salt, with the relative influencing weights being 18.01%, 17.84%, 15.17%, 10.98, 8.43%, 7.9%, 7.63%, 7.53% and 6.52 % respectively. That the influence of silicate on phosphorus nutrient variation is relatively great explained the structural changes of phosphorus nutrient and silicate played a vital role in the evolution of phytoplankton community. It also agreed with the fact that the red tide causative species have been evolving from medium-type (mainly diatom) to mini-type (mainly inoflagellate). Some environment factors such as silicate will, therefore, be taken into account to build the dynamics model of phosphorus nutrient and marine ecological model in the future.