Monitoring of Zyarat Stream by macro invertebrate fauna Golestan Province

Benthic macroinvertebrate fauna have importance role in biological cycle in water resources. This research was done in order to assess water quality using benthic macroinvertebrate. Sampling of benthic macroinvertebrate was achieved by surber sampler and the results showed no significant difference between different stations and months for each 5 indices (Shanon- winner, Margaloph, EPT/Shironomidae, Density and Symmetry indices) that the main cause of it was flood monthly that occurred. As for present results quality condition of Zyarat Straem was unsuitable, Also biological indices were as the suit indicatores of aquatic ecosystems beside of physio-chemical parameters and bactrial quality calculation show general appearance ecosystems.