Effects of water-nitrogen-salt coupling on soil water-salt distribution and cotton yield in oasis cotton fields

作者：Liu Keshun, Li Wenhao, Lyu Tingbo, Shuanglong Gao, He Jinyin · 发表于：DOAJ (DOAJ: Directory of Open Access Journals) · 年份：2026 · DOI：10.13522/j.cnki.ggps.2025346 · 研究领域：Irrigation Practices and Water Management、Biocrusts and Microbial Ecology、Soil Carbon and Nitrogen Dynamics

【Objective】Soil salinization and water scarcity are the main abiotic stresses affecting cotton production in Xinjiang oases. Optimal regulation of soil water, salt and nitrogen can alleviate these adverse effects. This paper experimentally investigated the effects of water–nitrogen–salt coupling on the spatiotemporal dynamics of soil water and salt, as well as growth and yield formation of cotton in a saline soil.【Method】The experiment was conducted in pots with drip irrigation. It included two irrigation treatments: 4 500 m3/hm2 (W1) and 3 600 m3/hm2 (W2), three nitrogen treatments: 200 kg/hm2 (N1) 300 kg/ hm2 (N2), 400 kg/ hm2 (N3), and three soil salinity levels: 2 g/kg (S1), 4 g/kg (S2), and 6 g/kg (S3). A partial least squares path model (PLS-PM) was used to identify the key pathways that control cotton yield formation.【Result】Soil water was predominantly distributed in the 20-40 cm soil layer, where the water content was 25.35%-60.09% higher than that in the topsoil (0-20 cm). As the crop grew, topsoil salinity initially decreased and then increased. Relative to its initial value, the average topsoil salt content decreased by 0.29 g/kg in the early growth stage and increased by 0.35 g/kg in the late stage. Increasing irrigation volume and nitrogen application effectively reduced soil salinity. Elevated soil salinity significantly inhibited cotton yield formation. The optimal irrigation and fertilization combinations for maximum yield under S1, S2 and S3 were W1N2, W1N2 ...