Abstract
The study had been achieved on the Great – Zab river at Eski Kalak monitoring station (3618 N , 4333- E , 280m A.S.1) during august 2009 and end of April 2010 (9 months).The river of Great – Zab drains on area of 31258 Km2, this area is located between latitude 35.3 , 38.06 N and longitude 42.5 46.05 E .dissolved load included some cations and anions were studied , and results showed that the concentration of cations decreased in the order of: Ca+2 > Mg+2 > Na+ > K+ .While the concentration of anions decreased in the order HCO3- > SO4= > NO3- > Cl- Results also showed that the amounts of monthly EC for the study period (9 months) were 0.46, 0.38, 0.38, 0.33, 0.33, 0.33, 0.37, 0.37, 0.38 dS/m respectively , and the amounts of pH for the same months were 7.4, 7.7, 7.6, 7.8, 7.5, 7.7, 7.9, 7.7, 7.9 respectively , On the other hand regression equations were developed between the river discharge and concentration of cations and anions and also between pH , EC and discharge and the recommended equations were given by using the general formula as follow: Log ( ion ) concentration = a + b Log flow + c (Log flow)2
