Abstract

Surface and subsurface drip irrigation methods can play a significant role in overcoming the scarcity of water mostly in water shortage areas. A field study was conducted to know the effectiveness of surface and subsurface drip irrigation systems under different plasticity pipes, in terms of both water use requirement and yield of date palms at Al-Qassim, Saudi Arabia. Mature palm trees of different varieties with 10 m spacing for both row to row and tree to tree were selected. Three types of pipes (low, medium and high flexible that is, with wall thickness of 1.14, 0.38 and 0.41 mm, respectively) were used in both surface and subsurface drip irrigation systems. Irrigation scheduling was done through a soil moisture sensing device as well as crop water requirement guidelines for Kingdom of Saudi Arabia to ensure enough soil water levels in the soil. Considerable effects of pipe stiffness were observed on water consumption and yield for both surface and subsurface drip irrigation systems. It was found that irrigation water reduced to 36 and 56% for drip pipes of low flexibility under surface drip irrigation system while it was 49 and 53% under subsurface drip irrigation system due to better physical and hydraulic characteristic of pipe as compared to that for medium and high flexibility pipes, respectively. The yield of date palms was increased by 45 and 48% more in case of low flexibility pipe compared to that for other two types under both drip irrigation systems. Date palm response by using low flexible pipe under both surface and subsurface drip irrigation was found relatively good in respect of water consumption, yield and irrigation system itself.

Key words: Surface drip irrigation, subsurface drip irrigation, date palm, arid region, pipe flexibility.