独流减河口浮游生物群落结构与环境因子的相关性研究

浮游生物在水生态系统具有独特的生态功能，为了揭示独流减河口浮游生物群落结构与环境因子的相关性，本研究于2015年5月和8月对独流减河8个站位浮游生物及环境因子进行了调查分析。结果表明:（1）调查期间共鉴定出浮游植物38种，浮游动物10种。5月浮游植物的平均丰度为3.32×105/L，8月浮游植物的平均丰度为1.36×106/L，5月浮游动物的平均丰度为64.40 ind/L，8月浮游动物的平均丰度为18.65 ind/L。（2）环境因子方面，5月的平均溶解氧为12.30 mg/L，8月的平均溶解氧为6.69 mg/L。5月的平均盐度为32.70，8月的平均盐度为33.29。硝酸态氮、亚硝酸态氮和总氮平均水平为8月高于5月。调查期间氮元素主要以硝酸态存在，8月氨态氮元素向硝酸态转化。（3）典范对应分析（CCA）表明，亚硝酸盐是影响浮游生物丰度及多样性差异的主要影响因子。高溶解氧利于桡足类浮游动物和绿藻生长，高温不利于桡足类浮游动物和绿藻的生长，而高温更适合蓝藻的生长。

Study on the correlation between community structure of the plankton and environmental factors of Duliujian river estuary

Plankton plays a unique role in aquatic ecological system. In order to make clear the correlation between community structure of the plankton and the environmental factors of Duliujian river estuary, investigations were made to 8 sampling sites in May and in August of the year 2015. In total 38 species of phytoplankton and 10 species of zooplankton were identified. The average density of phytoplankton in May was 3.32×105/L, and in August was 1.36×106/L. The Average density of zooplankton in May was 64.4 ind/L, and in August was 18.65 ind/L. For the environmental factors: the average DO concentration in May was 12.3 mg/L, and was 6.69 mg/L in August, the average salinity in May was 32.70, and in August was 33.29. Nitrate-N, Nitrite-N and Total Nitrogen level in August was higher than that of in May. In general, Nitrate-N was the major form of nitrogen during the investigation period. More ammonia was transformed to Nitrate-N in August. The CCA analysis showed that: NO₂- was the major factor influencing the abundance and diversity of the plankton. High DO level was beneficial to Copepods and Chllorophyta algae. High water temperature was harmful to the growth of Copepod and Chllorophyta, but was favorable to Cyanophyta.