Biological assessment Jajrood River using the Macrobenthos community structure

The current study aims to investigate the community structure of macrobenthos to evaluate water quality of Jajrood River, Northeast Tehran, Iran. We conducted this study in 12 stations during the Spring and Winter seasons of 2014-2015. The sampling method of macrobenthos is use of the surber sampler device with three replications in each station. We measured physical and chemical parameters in each station (temperature, pH, electrical conductivity, BOD, total suspended solids, nitrate, dissolved oxygen, ammonia, and fecal coliform). We used Canonical Correspondence Analysis to examine the effects of the physical-chemical parameters on the population distribution of macrobenthos. According to the results, we identified 11362 of  macrobenthos 6 orders and 25 families. The greatest frequency (52/56) of creatures belonged to the order Ephemeroptera, whereas the lowest frequencies (0.07) was seen in the order Coleopteran. Water temperature, ammonia, and electrical conductivity parameters had the largest effect in distribution of macrobenthos. The correlation between biology index and physical and chemical index of IRWQISC showed that margalef, TBI, and IBI indices were the best metrics that assessed water quality. Other than the Abnic and Taletange stations, the water quality in the other stations was unsuitable. We propose that efficient management practices should be implemented to improve water quality of this river.