Monitoring of Groundwater Salinity for Water Resources Management in Irrigated Areas of Al-Jouf Region, Saudi Arabia

Abstract

Groundwater salinity is an important limiting factor to sustainable irrigated agriculture in Saudi Arabia. The total groundwater salinity depends on the aquifer geology and its chemical characteristics. The main objective of this study was to monitor groundwater salinity for water resources management in irrigated areas of Al-Jouf Region of Saudi Arabia. A total of 117 water samples were collected from randomly selected small, medium and large agricultural farms from the whole region. The water samples were mainly analyzed for major cation and anions. The total groundwater salinity in less than 1000 mg LG1 in the whole region and falls in the category of medium to high salinity and medium to high sodicity water. Inter-ion relationship is very poor between major cations and anions. The EC and SAR relationship is very poor (R2 = 0.038). About 91% of groundwater is of sodium chloride type waters and the remaining 9% is that of sodium sulfate type water. The relationship between simple SAR and calculated SARs is very strong (R2 = 0.988 and 0.983). The results showed a replenishment of groundwater aquifer with the fresh water intrusion. In conclusion, to achieve higher water use efficiency, improvement water management practices such as application of leaching requirements, adoption of improved irrigation methods (drip and sub-surface irrigation) and proper crop selection need to be followed for increased agricultural production in the region.