Ecology, Environment and Conservation Paper

ASSESSMENT OF THE VALIDITY OF DIFFERENT TYPES OF IRRIGATION WATER FOR AGRICULTURAL PURPOSES AT AL HASSA OASIS, KSA (KINGDOM OF SAUDI ARABIA)

Adel A. Hussein, Ahmed S. El Mahmoudi, and Y. A. AL Molhem

Abstract

Al Hassa Oasis is one of the main agricultural areas in the Kingdom of Saudi Arabia and covers an area of approximately 20000 ha. About 8000 ha of Al Hassa Oasis is irrigated with groundwater, which considers the main source of irrigation water in this area. Nowadays, with the vast expansion in the agriculture and declining of groundwater resources, other water resources have been taken in account such as agriculture drainage water, tertiary treated wastewater and mixture of them for irrigation purposes. It is necessary to evaluate any source of irrigation water to reveal its impact on soil chemical, physical attributes, the growth and the yield of plants. The present study was conducted to evaluate different types of irrigation water at Al Hassa Oasis, for agricultural purposes. Twenty-five of irrigation water samples were collected from different areas located at the Oasis. The investigated irrigation water included six types, which are groundwater (GW), drainage water (DW), tertiary treated wastewater (TTWW), mixture of groundwater and drainage water (GW+DW), mixture of drainage water and tertiary treated wastewater (DW+TTWW) and mixture of groundwater, drainage water and tertiary treated wastewater (GW+DW+TTWW). The results of this study indicated that, the risk of using such types of water is concentrated in salinity hazard and potential salinity. The water salinity and sodicity classified as high to very high salinity hazard and low to high sodicity hazard. However, nine water samples, which are GW (samples No. 2 to 8), DW (sample No. 9) and GW + DW + TTWW (sample No. 15), were located out of diagram classification U.S. Salinity Laboratory Method. Therefore, this water can be used on coarse textured soils provided certain management practices such leaching requirements, selection of semi-salt tolerant crops and provision of adequate drainage are adopted.