شناسايي و تعيين زيتوده ماكروزيوبنتوزهاي رودخانه لاهيجان

Biomass estimation and identification of wacrozoobenthos in Lahijan river

This study was carried out monthly basis covering six sampling stations in Lahijan river in 2005-2006. The samples were collected by sorber sampler and determination of D.O., Water and air temperature, benthic biomass and identification of macrozoobenthos. The results showed that mean of air temperature 15.9°c, water temperature 14.8 ° D.O.6.3 mg/lit and mean of biomass 4.29 g/m2 and spatial maximum biomass was observed in summer with the average figure of 6.13 and minimum was in winter with the average figure of 2.41 g/m2 and maximum 7.33 g/m2 and minimum biomass 0.94 g/m2 of benthic organisms were observed in stations 6 and 1. Identification of macrozoobenthos showed orders of Ephemeroptera (8 Genus), Plecoptera (2 Genus), Trichoptera (3Genus), Diptera (6 Genus), Coleoptera (2 Genus) and flatwormes (2 Genus), Oilgocheta, (2 Family) and Crustacean (2 order). In the station 1,2,3 were clear water and station 4,5 were semiplluted and 6 station was with chironumus and Tubfex very polluted.