Structure pattern of Rotifer (Cuvier, 1798) in Pirbazar, Sheyjan, Bahmbar regions in Anzali Wetland and its relationship with environmental Indexes

Rotifers are important as being alive food for fish larvae aquaculture and as bio-indicator for evaluating the water quality of wetland ecosystems. In the present study, the sampling of rotifers carried out in three regions of the Anzali wetland including Pirbazar, Sheyjan and Bahambar, during 2016-2017. In this investigation, 29 genera of rotifer from 17 families belonging to the two subclasses of Monogononta and Bdelloidea were identified in the sampled region. The highest and lowest abundance of rotifers observed in Pirbazar during summer and in Bahmbar during winter, respectively. Results of CCA revealed a positive correlation between rotifers’ density and temperature, pH, total phosphorus and total nitrogen and also a negative correlation with dissolved oxygen in Pirbazar region. The abundance of some rotifer genera such as Filinia, Brachionus and Polyarthra showed a positive correlation with temperature and Keratella abundance had a negative correlation with dissolved oxygen. Based on the TRIX index, the water of Pirbazar region was richer than Sheyjan and Bahmber regions.