鳜塘水质与原生动物群落多样性关系的初步研究

The relationship between protozoan community diversity and water quality in ponds for the culture of Siniperca chuatsi

通过对水体理化因子和PFU原生动物群落的监测,主要研究了鳜塘水质与原生动物群落多样性之间的关系,结果表明:(1)半封闭养殖模式下,鳜塘水质综合评价指数在养殖过程中逐渐升高,而PFU原生动物多样性逐渐减少。(2)PFU原生动物多样性(y)能够很好的评价鳜塘水质,其与水质综合评价指数(x)之间成负相关关系,可用公式y=2.45-2.54lnx表示,相关和回归分析均表明,水质综合评价指数与原生动物群落多样性指数之间的对数函数关系十分密切,且具有极显著意义。本实验结果还表明,原生动物多样性指数与鳜疾病的发生之间存在着一定的关系,这为鳜疾病预报预测模型的建立初步筛选了一个生物指标。

The relationship between the diversity of protozoan community and water quality in ponds for the culture of Siniperca chuatsi was studied through the detection of pond water physicochemical factors and the observation of plolyurethane foam unit（PFU） protozoan community. The experiment was conducted from September to November in 2004 at Shunde, Guangdong Province. Water physicochemical factors were determined by common method and water quality index was constructed according to GB3838 - 88. Protozoan samples were collected by PFU method and protozoan community diversity index was calculated by Margalef formula. The results showed that some factors such as TN （ NH4 - N, NO2 - N and NO3 - N） and chemical oxygen demand （COD） increased gradually as cultivation progressed. The results also showed that the water quality index increased in cultivation progress. The opposite trend was observed for the diversity of protozoan community. The water quality index and protozoa community diversity index can he used for evaluating water quality. The relationship between PFU protozoan community diversity index（y） and water quality index（ x ） could be expressed by y = 2.45 - 2. 54Inx, that is to say, the higher water quality index is, the lower the protozoan community diversity index is. Through correlation and regression analysis, coefficient of correlation and regression is significant at 0.01 level. It is also found that there is a relationship between protozoan community diversity index and S. chuatsi diseases. Protozoan community diversity index would become a good biofactor for prediction of S. chuatsi diseases.