Drip‐irrigation using highly saline groundwater increases sunflower yield in heavily saline soil

Abstract

To improve global food security, techniques for sustainability managing salinity are needed. The objective of this study was to find a sustainable cultivating method for grain production using saline groundwater. A field experiment was conducted to determine the effect of drip irrigation with saline water (EC = 9.5 dS m -1 ) (DIS), drip irrigation with freshwater (electrical conductivity [EC] = 1.3 dS m -1 ) (DIF), and flood irrigation with freshwater (CK) on sunflower (Helianthus annuus L.) yields.The cultivation pattern of "scheduled drip irrigation + mulched ridge" was adopted in DIS and DIF, while that in CK was the local pattern of "flood irrigation + flat mulch". Results showed that drip irrigation with saline water and drip irrigation with freshwater saved 95% and 43 freshwater when compared with CK. After 2 yr, soil electrical conductivity of saturated paste extracts (ECe) in the surface 40 cm decreased from 22.9 to 6.4 dS m -1 in DIS and from 17.9 to 5.4 in DIF. The calculated desalinization rates were 72.1% for DIS and 69.3% for DIF. The sunflower yield in DIS and DIF increased by 12.1 and 37.0% and the economic benefit correspondingly increased by 29.6 and 52.5% when compared with CK after 2 yr. The drip irrigation with saline groundwater had remarkable advantages in saving freshwater, leaching salt, and increasing income. INTRODUCTIONWorld-wide food security is threatened by salinity and increasing competition for freshwater supplies. Due to differences in soil characteristics and different climates, local innovations are needed to solve this problem. The Hetao Plain, located in Northwest China, has an irrigated land area of 570,000 ha, which is irrigated with water from the

Effects of saline water with different concentrations of calcium and magnesium ions on emitter clogging in drip irrigation integrated water–fertilizer system

“…Saline water with a high soluble salt concentration is required for agricultural irrigation, especially in dry and semi‐arid locations (Malash et al, 2008). Drip irrigation is regarded as one of the most appropriate methods for saline water irrigation because of its precision, controllability, water efficiency and yield‐increasing characteristics, which can transfer and accumulate salt in the irrigation water to the edge of the soil moisture body and effectively reduce the salt stress levels in the crop root zones (Chen et al, 2010; Dong et al, 2021; Malash et al, 2005). However, saline water has a high concentration of salt ions (such as Ca 2+ , Mg 2+ , Fe 2+ , CO 3 2− , PO 4 3− and SO 4 2− ), which easily recombine and precipitate salts inside the emitter, thereby blocking the emitter (Shi et al, 2022).…”