The effect of environmental factors on body size indices and the diversity of macrobenthic communities in Gomishan Lagoon and Miankale Bay.

Body size is a fundamental characteristic of organisms and is expected to decrease in response to environmental stresses such as heat stress, and its estimation is an important step in addressing many ecological questions in aquatic environments. The aim of this study was to investigate the effect of environmental factors on body size and diversity of macrobenthos communities in Gomishan wetland and Miankaleh Bay. For this purpose, macrobenthos was carried out by leaf packages in summer 2017. The results showed that the average temperature, salinity and electrical conductivity in Gomishan lagoon were higher than Miankale Bay, but no difference was observed in terms of dissolved oxygen and pH. The average dry weight and total length of the Zygoptera showed no significant difference, Shannon's species diversity and evenness indices showed a significant difference in two ecosystems. The results of covariance analysis between dissolved oxygen, salinity, body weight and abundance on leaf pack decomposition showed that only water salinity has an inverse relationship with the decomposition rate. The results of factorial rotation matrix showed that temperature, longitude and latitude and k-day had a positive effect and pH, salinity and oxygen had a negative effect on the abundance of macrobenthos. The results showed that the changes in environmental parameters such as temperature had an effect on the metabolism and weight of the biomass of different species, so that the average weight of many different species in the warmer water of Gomishan Lagoon was lower than that of Miankaleh Bay.