Suction of Soil Particles under Vacuum Conditions in Subsurface Drip Irrigation: Comparative Test of Emitters

摘要

Subsurface drip irrigation (SDI) presents an inherent risk of suctioning soil particles from the surrounding porous media due to vacuum occurrence inside lateral lines underground that can result emitter clogging. This work aims to evaluate the vacuumoccurrence effect on 26 drip models under SDI conditions. The treatments consisted in the application of four vacuum levels -10, -15,-20 and -40 kPa in two soil textures: sandy and clay. The obtained values of flow rate were used to calculate average flow rate (qm), discharge variation coefficient (CV) and uniformity distribution coefficient (UD). Random block was the statistical delineation adopted, "F" tests was used to the variance analysis and Tuckey test with 5% probability to averages comparisonsand regression analysis. Subsurface drip emitter's performance was influenced by the soil texture. The highest vacuum level -40 kPa present the major emitters obstructions with reduction in the flow rate for both soil textures. Some emitters presented variable results according to soil texture and constructive design.