Institute of Farmland Irrigation of Chinese Academy of Agriculture Sciences, Ministry of Agriculture and Rural Affairs, Xinxiang, 453002, China; Graduate School of Chinese Academy of Agricultural Sciences, Beijing, 100081, China.
Institute of Farmland Irrigation of Chinese Academy of Agriculture Sciences, Ministry of Agriculture and Rural Affairs, Xinxiang, 453002, China.
J Environ Manage. 2024 Feb 14;352:120087. doi: 10.1016/j.jenvman.2024.120087. Epub 2024 Jan 12.
Saline water has proven to be one of the alternative sources of freshwater for agricultural irrigation in water-scarce areas. However, the changes in farmland ecology caused by saline water irrigation remain unclear. In this study, six irrigation water salinities (CK: 1.3 dS m, S1: 3.4 dS m, S2: 7.1 dS m, S3: 10.6 dS m, S4: 14.1 dS m, S5: 17.7 dS m) were set in a three-year (2019, 2021-2022) experiment to investigate their effects on soil environment and greenhouse gas emissions in cotton fields under long-term saline water irrigation. Results show that soil salinity in the same layer increased as increasing water salinity. Soil moisture of S3-S5 increased significantly by 4.99-12.94%. There was no significant difference in soil organic matter content between CK and S1. Saline water irrigation increased soil ammonium nitrogen content by 0.57-49.26%, while decreasing nitrate nitrogen content by 1.43-32.03%. Soil CO and NO emissions and CH uptake were lower in S1-S5 than in CK at different cotton growth stages. In addition, saline water irrigation reduced the global warming potential by 6.93-53.86%. A structural equation model was developed to show that soil salinity, moisture, and ammonium nitrogen content were negatively correlated with global warming potential, while organic matter and nitrate nitrogen had positive effects on global warming potential. Considering the comprehensive perspectives of gas emissions and cotton yield, irrigation water with salinity less than 10.6 dS m could effectively reduce greenhouse gas emissions from cotton fields while maintaining stable cotton yields in the experimental area and similar region.
盐水已被证明是缺水地区农业灌溉的淡水替代水源之一。然而，盐水灌溉对农田生态的影响尚不清楚。本研究在三年（2019、2021-2022 年）的试验中设置了 6 种灌溉水盐度（CK：1.3 dS m、S1：3.4 dS m、S2：7.1 dS m、S3：10.6 dS m、S4：14.1 dS m、S5：17.7 dS m），以研究长期盐水灌溉对棉花田土壤环境和温室气体排放的影响。结果表明，同一土层的土壤盐分随灌溉水盐度的增加而增加。S3-S5 的土壤水分分别显著增加了 4.99-12.94%。CK 和 S1 之间的土壤有机质含量没有显著差异。盐水灌溉使土壤铵态氮含量增加了 0.57-49.26%，而降低了硝酸盐氮含量 1.43-32.03%。在不同棉花生长阶段，S1-S5 的土壤 CO 和 NO 排放和 CH 吸收均低于 CK。此外，盐水灌溉使全球变暖潜势降低了 6.93-53.86%。建立了结构方程模型，表明土壤盐分、水分和铵态氮含量与全球变暖潜势呈负相关，而有机质和硝酸盐氮对全球变暖潜势有正效应。考虑到气体排放和棉花产量的综合观点，在试验区和类似地区，灌溉水盐度小于 10.6 dS m 可有效减少棉花田的温室气体排放，同时保持棉花产量稳定。
