太子河浮游植物初步调查及鲢鳙鱼产力评估

Preliminary Investigation on Phytoplankton and Estimation to Silver Carp and Bighead Carp Productivity of Taizi Lake

2010年6-10月对江西省南昌市蒋巷镇太子河养殖水域浮游植物进行调查。结果表明,太子河有浮游植物5门、74种;其中,绿藻门种类数最多(占藻类总种数的48.64%),其次是蓝藻门(29.72%)和硅藻门(14.86%)。10月的浮游植物种类最多,其次为9月和8月,7月最少。浮游植物密度7月最高,为313×105个/L,其余月份浮游植物密度相差不大,变化范围为(79～101)×105个/L,蓝藻门微囊藻属是绝对优势种。浮游植物Shannon-Wiener多样性指数及均匀度指数7月最低,分别为0.10、0.03,其余月份Shannon-Wiener指数范围为0.37～0.69,均匀度指数范围为0.10～0.18。综合分析浮游植物密度、多样性指数和均匀度指数,太子河水体存在富营养化。浮游植物对鲢鳙的鱼产力估算为12.675 kg/hm2。

From June to October 2010,the investigation for phytoplankton species composition was carried out in Taizi River,which locates in Nanchang City,Jiangxi Province.The results showed there were 74 species belong to 5 phylums were found in the river.Chlorophyta was the mainly species（48.64% of the sum）,followed by Cyanophyta（29.72% of the sum） and Bacillariophyta（14.86% of the sum）.There was the most species of phytoplankton in October,followed by September and August,while the least was in July.The density of phytoplankton in July was the highest,for 313 × 105cells/L.The density of phytoplankton in other months differed little,ranged from（79-101） × 105 cells/L.Microcystis which belongs to Cyanophyta was the absolutely dominant species.The Shannon-Wiener diversity index（H′） and evenness index（J） were the lowest（0.10 and 0.03 respectively） in July.For the other months,the Shannon-Wiener diversity index ranged from 0.37 to 0.69,evenness index ranged from 0.10 to 0.18.Comprehesive of phytoplankton density,Shannon-Wiener diversity index and evenness index,indicating that water was at the level of eutrophication.The productivity of silver carp and bighead carp estimated on the basis of the productivity of phytoplankton was 12.675 kg/hm2.