The water quality of Zayandeh-rood river with Macrobehthos biodiversity indexes in fall 2017 to Spring 2018

The purpose of this study is to conduct a qualitative analysis of Zayandeh-rood River water using benthic invertebrate communities in fall 2017 to Spring 2018. To do so, we select 6 stations and 3 sediment samples were collected in each stations. Sediment samples were fixated and various animals were extracted from the samples and were grouped and identified according to fauna benthic identification keys were used for the identification of the sample. Finally, in spring 8 family belongs to 6 order; in autumn 11 family belongs to 7 order and in winter 6 family belongs to 4 order were identified. According to all indices, all stations and all seasons were in polluted category. Regarding the Zayandeh-rood drought, during the last decade, the flow of water in the river, especially the refinery stations and the Shakh-kenar and Sharif Abad, is practically the industrial wastewater, sewage of the cities and adjacent villages. For this reason, contaminated species in these ecosystems are species resistant to pollution.