پديد آورندگان :
Parisa، Piroozfar Department of Geology - Faculty of Sciences - Urmia University , Samad، Alipour Department of Geology - Faculty of Sciences - Urmia University , Soroush، Modabberi School of Geology - University of Tehran , David، Cohen School of Biological - Earth and Environmental Sciences - New South Wels University - Sydney - Australia
كليدواژه :
Water quality assessment , Sarough watershed , Hydrogeochemistry , PCA , Piper Diagram
چكيده لاتين :
This study investigated the hydrogeochemistry and environmental water quality of rivers
in Sarough watershed using the major ion chemistry and explored multivariate statistical
methods for identification of processes which release the solutes in natural waters. Totally, 38
samples were collected along the main streams of the watershed. The mean concentrations of
major cations (Na, K, Mg, Ca) and anions (Cl, NO3, CO3, HCO3, SO4) were measured about
15, 4.6, 10.5, 61, 30, 4.49, 89, 156 and 107 mg/l, respectively. The results indicated that the
river waters in the Sarough watershed were neutral and fresh water in nature (mean values:
pH=7.7 and TDS= 315.8 mg/l). Most of the water samples were categorized in hard and very
hard water classes with mean value for TH=197 mg/l and were under-saturated regarding with
major carbonates, sulfates and evaporate minerals in most of samples. The major water types
were Ca–HCO3–SO4, Ca–Mg–CO3 and Ca–SO4–HCO3. The Na, Cl and NO3 concentration
in all water samples fell within the accepted limit of national and international standards for
drinking water. Nevertheless, Ca, Mg and SO4 content in some samples were higher than
the maximum desirable limits. Schuler diagram showed that majority of the water samples
were good and acceptable for drinking. Evaluating the quality of river water for irrigation
purposes using Wilcox diagram and SAR, EC and RSC indices indicated that majority of the
water samples were suitable for irrigation. The results of multivariate statistical techniques
such as correlation coefficient matrix, CA and PCA indicated the strong association between
Na-K-Cl-SO4 and Ca-Mg-CO3-TH. It was assumed that weathering of carbonates
(limestone/dolomite formations, calcareous marl formation and travertine) in the area were
common source of Ca, Mg and HCO3. Also, travertine springs were considered as active
point sources which release these elements into the drainage system. Meanwhile, dissolution
of halite and gypsum in red marl formations (lower part of Qom F. and Upper Red F.) were
the main processes considered as the origin of Na, K, Cl and SO4 in river water of study area.
