裸甲藻种群密度与理化因子的灰关联分析

Grey Analysis of Relationships between Abundance of Gymnodinium spp.and Seawater Physico-chemical Factors

为了探讨裸甲藻种群密度与各环境因子的关系,并为裸甲藻赤潮的防治提供科学依据,根据2011年5—8月对河北省秦皇岛近岸海域进行的水质环境调查数据,采用灰色理论的系统分析方法,研究并计算了裸甲藻的种群密度与8项环境理化因子的灰关联度及关联排序。研究结果表明,秦皇岛近岸海域氮∶磷、无机氮、无机磷、硅酸盐是影响裸甲藻种群增殖态势的主要因素,而化学需氧量、温度、盐度和pH是次要因素。裸甲藻高密度出现的氮∶磷、水温和氮、磷、硅的含量分别为10~30、17~20℃、0.1、0.005、0.1mg/L;裸甲藻化学需氧量为1.04~3.20mg/L,分布均匀;盐度为31~32,pH 7.8~8.1,对裸甲藻种群密度无显著影响。

The grey related values between population density of Dinoflagellate Gymnodinium separately and eight various related physical-chemical factors of seawater were calculated in offshore marine areas of Qinhuangdao based on the environmental survey data in off-shore of Qinhuangdao from May to August, 2011 in order to provide scientific basis for prevention and treatment of Gymnodinium red tide. The results showed that N ＇ P, DIN, DIP, and silicate had more influence on Gymnodinium population multiplication than other factors, followed by COD, temperature, salinity and pH. High cell density of Gyrnnodinium was only observed under the conditions of N ： P ratio from 10 to 30 , water temperature of 17-20 ℃, nitrogen content of about 0.1 mg/L, phosphorus content of some 0.005 mg/L and silica content of about 0.1 mg/L. Gymnodinium was evenly distributed at COD of 1.04-3.2 mg/L, and there was no significant change in Gymnodinium population density at a salinity of 31-32 and pH 7.8-8.1.