| This article has been：Browse 255Times Download 49Times |
scan it! |
|
|
| DOI：10.13522/j.cnki.ggps.2025274 |
|
| Combined effects of irrigation and drainage on water, heat and salt dynamics in saline soils during the freezing-thawing period |
|
LYU Hang, LI Xu, LI Wangcheng, JIA Zhenjiang, WU Yangyang,
AN Wenju, HUANG Yahao, MA Dongxiang
|
|
1. School of Civil and Hydraulic Engineering, Ningxia University, Yinchuan 750021, China;
2. Engineering Research Center for Efficient Utilization of Modern Agricultural Water Resources in Arid Regions,
Ministry of Education, Yinchuan 750021, China; 3. Ningxia Hui Autonomous Region Key Laboratory of
Yellow River Water Network Digital Water Control, Yinchuan 750021, China
|
| Abstract: |
| 【Objective】Saline-alkali soils are widely distributed in the Yinbei Irrigation District of Ningxia, and coordinated irrigation and drainage management is critical to preventing secondary salinization in this region. This paper investigates the combined effects of irrigation and drainage on soil water, heat, and salt dynamics during the freezing-thawing period, with the aim to find a practical strategy to improve efficient utilization of these soils.【Method】The experiment was conducted using soil columns packed with salinized soil to represent a winter irrigation. It consisted of three irrigation treatments: 900 m3/hm2 (W1), 1 350 m3/hm2 (W2), and 2 400 m3/hm2 (W3), and two drainage treatments: with drainage (D1) and without drainage (D2). During the experiment, spatiotemporal variations in soil water, heat, and salt were measured in all treatments during a freezing-thawing period.【Result】Irrigation played the dominant role in influencing water and salt migration, as well as heat transfer throughout the soil profile in all treatments. In particular, W2 treatment resulted in the largest variation in water, heat, and salt in the 5 cm soil layer compared to that in the 15-70 cm soil layers. Water, heat, and salt migration were strongly correlated in the 15-25 cm soil layers in all treatments, with correlation coefficients ranging from 0.63 to 0.99. Drainage significantly enhanced the downward migration of soil water and salt. Overall, the temperature variation in the W2D1 treatment showed a hysteresis effect within the soil profile; water and salt migrated deeper in this treatment than in others, demonstrating a strong synergistic effect of irrigation and drainage on soil water and salt movement.【Conclusion】A winter irrigation amount of 1 350 m3/hm2 combined with a drainage can optimally regulate the migration of water, salt, and heat during the freezing-thawing period in saline soil profile. These findings provide practical guidance for efficient utilization of saline soil and mitigating secondary salinization in the Yinbei Irrigation District. |
| Key words: Yinbei irrigation district; coordination of irrigation and drainage; saline soil; freezing-thawing period; water-heat-salt migration |
|
|
