A novel variable discharge emitter for irrigation and salt-leaching

Enhancing the utilisation rate and productivity of saline-alkali land is critical in ensuring sufficient cultivated land resources and food security. Although drip irrigation technology maintains the crop yield in saline-alkali land, the irrigation water amount must be higher than the crop demand. To address this, the present study develops a novel variable discharge emitter (VDE), which consists of an upper cover, a bottom cover, and a diaphragm with a linear incision. The experimental results showed that the VDE achieved two rated discharge levels of 4.1 L h⁻¹ and 9.7 L h⁻¹ when the working water pressure was at 0.10 MPa and 0.16 MPa and when the length of the incision, the thickness of the diaphragm, and the hardness of diaphragm inside the VDE were 3.5 mm, 1.5 mm, and 55.0 HA, respectively. It suggests that VDE has two rated discharges for irrigation and salt-leaching based on two working water pressure ranges.