正常与发病对虾养殖池塘浮游藻种类组成和异养细菌数量比较

通过拖网法和平板涂布细菌计数法,比较了正常与发病凡纳滨对虾养殖池塘浮游藻种类组成和异养细菌数量的差异。在四个虾池共观察到浮游藻类31属40种,它们分别属于硅藻Bacillariophyta、绿藻Chlorophyta、蓝藻Cyanophyta、甲藻Pyrrophyta、裸藻Euglenophyta、隐藻Cryptophyta和黄藻门Xanthophyta,仅二形栅藻和颤藻在四个池内都能观察到。正常池中无论是门类还是种类都超过发病池。正常池中蓝藻的含量分别为6.16%和9.77%,明显低于发病池的18.85%和43.38%。两个正常池浮游藻类的多样性指数和均匀性指数也明显高于发病池,不同池间浮游藻类群落的相似度与对虾发病与否无关。发病虾池水中的总异养菌数比正常虾池中的都高一个数量级。

Comparison of species composition of phytoplankton and heterotrophic bacteria number between normal shrimp culturing ponds and disease-occurred ponds

The species composition of phytoplankton and heterotrophic bacteria number in the normal shrimp culturing ponds were compared to those in the disease-occurred ponds by trawling method and spread plate method.The results showed that 40 species of phytoplankton in 31 genera were observed,which belonged to Bacillariophyta,Chlorophyta,Cyanophyta,Pyrrophyta,Euglenophyta, Cryptophyta and Xanthophyta;however,only Scenedesmus dimorphus(Turp.) Kutz.and Oscillatoria sp.were observed in the four studied ponds.There we...