Effects of Different Irrigation Rates on Leaf Water Potential and Soil Water Potential of Populus euphratica Forest

【Objective】 To study the effects of different irrigation rates on leaf water potential and soil water potential of Populus euphratica forest, and to provide technical support for scientific flood diversion irrigation of Populus euphratica forest. 【Methods】 Populus euphratica forests of 2 to 4 years along the middle and lower reaches of Tarim River was taken as the research object, different irrigation rates (20,40 and 60 L/m²) were set up. WP4C dew-point water potential meter and TPSBR-SZL sensor were used to measure leaf water potential and soil water potential of Populus euphratica, and WET three-parameter soil tachymeter was used to measure soil water content, temperature and electrical conductivity before and after irrigation. 【Results】 The diurnal variation of leaf water potential and soil water potential of Populus euphratica under different irrigation rates showed a pattern of 60 L/m²>40 L/m²>20 L/m²>CK. The diurnal variation of leaf water potential of Populus euphratica showed a single-peak "V" shape, which was higher in the morning and lower after the noon. The diurnal variation of leaf water potential and soil water potential under 40 and 60 L/m² treatments were all less than that under 20 L/m² and CK. The soil water content affected the water potential of Populus euphratica, and the decrease of soil conductivity and temperature was beneficial to the decrease of soil salt. 【Conclusion】 Repeated irrigation promotes the growth of Populus euphratica trees in arid area. The diurnal variation of leaf water potential and soil water potential is 60 L/m²<40 L/m²<20 L/m²Populus euphratica is 60 L/m², 40 L/m² and 20 L/m², respectively.