| Popis: |
Chemical characteristics of groundwater and the composition of newly formed precipitates are critical in the management of modern irrigated agriculture in arid regions. Water samples representing the main aquifers in Riyadh region, Saudi Arabia, and solid samples fromthe newly formed precipitates were studied. Results showed that water temperature varied between 30.3-69°C, being higher in the deep aquifer and low in the relatively shallow aquifers. Initial water pH ranged from 6.39-7.92, increasing to 7.65-8.20 at atmospheric conditions. Shallowaquifer waters were categorized into sulfate-type and Cl- or no-dominant type waters, while the deep aquifers were characterized as Cl-type and no-dominant type. Soluble H 4 SiO 4 , soluble Fe and Mn ranged from 3.15 to 18.82, 0.10 to 17.30, and 0.01 to 4 0.32 mg L-¹, respectively. Calculation of saturation indices from water composition at initial, closed and equilibriumconditions indicated that changes in pH and water temperature cause major chemical changes in t... |
