Document Type : (original research)
Department of Fisheries, Science and Research Branch, Islamic Azad University, Tehran, Iran.
Faculty of Veterinary,, University of Tehran
Department of Fisheries Science, Science and Research Branch, Islamic Azad University, Tehran, Iran
Iranian Fisheries Research Organization, Caspian Sea Ecology Research Institute, Sari, Iran
The aim of this study was to evaluate the impact of human activities on health and determination of water quality using biological index of macroinvertebrates functional feeding groups. Sampling of macroinvertebrates was monthly performed using a surber sampler from 4 stations in 2017. During one year of sampling, 46475 samples of macroinvertebrates were collected belonging to 16 orders, 35 families and 49 genera. Macroinvertebrates included five functional feeding groups including Collector-Filterer (CF), Collector-Gatherer(CG), Scraper (SCR), Shredder (SHR), Predator (PRD) and Parasite. CG and CF groups had the highest relative frequencies in all study stations, except station 3, where CG and PRD groups were dominant, respectively. In stations with high pollution (especially station 1), the frequency of CG feeding group has increased significantly compared to other stations (especially stations 2 and 4) (ANOVA; F=0.011, p<0.05). Based on the results obtained from the distribution of macroinvertebrates and their food behavior, the impact of human activities including the entry of agricultural, urban, and rural wastewaters to the little Zab river is quite evident and the stations affected by different types of effluents (Station 1 and 4) had the most unfavorable conditions. Therefore, by examining the macroinvertebrates functional feeding group with the least time and cost, it is possible to find possible anomalies caused by human activities and changes in water quality of little Zab river ecosystems.