Taxonomical study of Bacillariophyta as index of water quality in Khuzestan province

Diatoms were identified from 31 different stations in the Karun and Dez Rivers in Khuzestan, southwest Iran. A total of 68 species belonging to 32 genera were registered and the algal flora of water bodies shows the dominance diatoms like, Asterionella formosa, Nitzschia palea, N. ovalis, Navicula radiosa., N. salinarum,. N. lanceolata, Cocconies placentula., C. pediculus, Gomphonema truncatum., Gomphonema olivaceum var. olivaceum; Cymbella affini, Ulnaria ulna, U. acus., Gyrosigma acuminatum., Diatoma hyemalis.and D. vulgaris. As well as, results of the physical-chemical parameters show that temperature, COD and pH have effective role on the diatoms composition. Navicula, pinnularia, Eudorina and Melosira were found to be useful as indicators of some physico-chemical properties of water. It is now appropriate that the full potential of the use of diatoms in water quality assessments, and the information contained in the collection be developed and utilized in Iran Rivers.