Evaluation of zooplankton community and saprobi index of carp's culture ponds (Case study: East of Golestan Province-Gonbade Kavous city)

The aim of this study was to evaluate of zooplankton communities as bioindicator of water quality and saprobi index at six Chinese carp ponds at East of Golestan province¡ Gonbade Kavous city. Zooplankton sampling was done monthly during one culture period from June to November 2011. Finally¡ 27 genus from 4 class were identified. Between these groups¡ 12 genus belong to Protozoa¡ 8 genus from Rotatoria¡ 4 genus from Copepoda and 3 genus from Cladocera were recorded. The highest and lowest frequency percentage were belongs to Rotatoria and Protozoa with 46 and 3 percent¡ respectively. The results show that¡ there is no significant differences between saprobi index of six ponds (p>0.05). During the whole period of study¡ the saprobi index indicated Class ß-mesosaprob as water quality. There was significant general tends of decrease in the saprobi index from the beginning to end of the culture period (p