| In order to explore the effects of brackish water irrigation with different cation compositions on soil pore structure under mulch, a two-year field location experiment was conducted, including local groundwater irrigation (CK), NaCl brackish water irrigation (T1), KCl brackish water irrigation (T2), CaCl2 brackish water irrigation (T3) and MgCl2 brackish water irrigation (T4). The effects of brackish water with different cation compositions on soil pore structure were studied by CT scanning technology. The results showed that:Compared with CK treatment, with the increase of irrigation times, the soil macroporosity of Na+ treatment was significantly decreased, and the soil macroporosity of K+, Ca2+ and Mg2+ treatments was significantly increased. In 2022, the soil macroporosity of Na+ treatment decreased by 44.49% on average, and the soil macroporosity of K+, Ca2+ and Mg2+ treatments increased by 5.73%, 80.73% and 25.75%, respectively; During 2021 and 2022, compared with CK treatment, the soil pore rounding rate of the four different cation treatments showed an increasing trend, among which the soil pore rounding rate of Ca2+ and Mg2+ treatments increased significantly, and the average increase range of soil pore rounding rate was 25.52%~0.94% and 17.46%~23.19%, respectively; After continuous irrigation for two years, the soil cracking degree of Na+ and K+ treatments was aggravated, and the soil stability was becoming worse and worse, while the soil structure and infiltration performance of soil were improved obviously by adding Ca2+ and Mg2+ treatments. |