三氯异氰尿酸对养殖海域浮游植物生长的影响

Effects of TCCA on growth of phytoplankton in mariculture areas

选取我国近海浮游植物优势种类尖刺拟菱形藻(Pseudo-nitzschia pungens)、球形棕囊藻(Phaeocystis globosa)、东海原甲藻(Prorocentrum donghaiense)、塔玛亚历山大藻(Alexandrium tamarense)和锥状斯氏藻(Scrippsiella trochoidea),采用实验室培养技术研究了常用渔药三氯异氰尿酸(TCCA)对养殖海域浮游植物生长的影响。结果表明,在较低浓度范围内TCCA对浮游植物的生长具有促进作用,而在高浓度时则具有显著的抑制作用。TCCA对浮游植物的毒性效应具有种间差异,甲藻类的耐受力明显强于其它种类。在高浓度TCCA作用下,甲藻的生长出现延滞现象:指数生长期滞后,特定比增长率和叶绿素a含量明显增大。从长期影响来看,在富营养条件下浮游植物对TCCA的耐受力增强。因此,TCCA等类似有毒有机物可能通过促进甲藻而抑制硅藻和其它藻类的增殖,进而对浮游植物群落结构产生深远影响。

Effect of a representative disinfectant TCCA on the growth of several dominant phytoplankton species （Prorocentrum donghaiense , Alexandrium tamarense , Scrippsiella trochoidea , Pseudo-nitzschia pungens and Phaeocystis globosa ） , which widely distributed in the maricuhure areas of China, was studied in laboratory. It showed that the growth of phytoplankton species was stimulated under the low concentrations of TCCA. However, the growth of algae was inhibited markedly under the high concentrations of TCCA. And the effect of TCCA was different among different species. The resistance of dinoflagellates on TCCA was much better than other species. On account of long term effect, the resistance of phytoplankton on TCCA was higher in the eutrophication waters. As a result, poisonous compounds such as TCCA potentially play an important role in the regulating structure in phytoplankton community.