The Density And Distribution Of The Plankton In Karganrood River

A comprehensive hydrobiological and hydrological investigation was down on Karganrood river has situated in west of Guilan from 2001 to 2002. The results of this study reveal that, there are totally 4 phyla of phytoplankton that include 16 genera,and maximum density of phytoplankton belong to the Phylum bacillariophyta with genera navicula, nitzchia, diatoma, cyclotella, gomphonema and cocconeis, which yearly average numbers calculated 370800/ lit, It has %95.6 Phytoplankton population, which observed during the year.After Bacillariophyta there was Cyanophyta with genus Oscillatoria, which yearly average numbers calculated 15307/ lit, it has %4 Phytoplankton population during year. Chlorophyta with genera cosmarium and cruciginia has yearly average numbers 1057/lit with %0.3 Phytoplankton population and euglenophyta with genus trachelomonas has yearly average numbers 529 / lit with %0.1 phytoplankton population in this river. Zooplankton study revealed that population in Karganrood river is very poor and mostly belong to fixed zooplankton similar Rhizopoda and some of Rotatoria. In Zooplankton introduce 5 Phyla and 11 genera which the highest dencity belong to Phylum Rhizopoda, with genera arcella, difflugia, cyphoderia and euglypha, which yearly average numbers calculated 2.1/ lit,it has %45 zooplankton population during year. Nematoda with yearly average numbers 0.9/ lit had %19, ciliophora with genus vorticella which yearly average numbers 0.8/lit and rotatoria with genera keratella, cephalodella, synchaeta and philodia with yearly average numbers 0.8/lit, each of them had %17 zooplankton population during the year. Arthropoda with genus harpacticus which yearly average numbers 0.3/lit had thinly populated in Karganrood river. It has %2 zooplankton population in year.