Assessment of Water Quality of Gaseous Wells and Its Suitability for Agricultural Uses in the Hameh-Kasi Area, Hamedan Province

Due to the important role of irrigation water chemical composition in the yield of crops and its effects on the soil structure, it has been taken into consideration by the agricultural sector planners. In this regard, the sour and burning taste of water in some agricultural wells around the HamehKasi village in Hamedan province has caused concerns about their water composition and possible detrimental effects on soil stucture and plant growth. Therefore, the present study was conducted to evaluate the water quality and the trend of changes in its composition. In this study, 6 gaseous water-wells were identified and their salinity was measured 15 times in three years (5 times each year), and the trend of their electrical conductivity changes was evaluated by SPSS software. Also, from each well, one sample was taken in order to determine the electrical conductivity, cations and anions content, and their chemical indices were calculated and evaluated by means of different criteria and diagrams. The results showed that calcium and bicarbonate ions have the highest concentrations in these waters, and the water of the mentioned wells was considered as unconventional and was Ca-Mg-HCO3 type. The water salinity of these wells was high (from 2.96 to 6.07 dS/m), and had very high salinity and sodicity (C4S4) after correction of the sodium adsorption ratio. Due to high salinity of water, fine-textured soil and lack of sufficient water for leaching, it is expected that the soil will be salinized in the root zone by irrigation, and as a result, the yield of plants and especially perennial plants would decrease. However, the statistical analysis of the electric conductivity changes of gaseous water-wells in HamehKasi area indicated that the salinity of their water decreased significantly over time. Consequently, the quality of water in the HamehKasi area in terms of irrigation improved over time.