| 引用本文: | 范理权,史海滨,闫建文,等.局部秋浇条件下冻融期“秋浇-春灌”农田土壤水盐归趋研究[J].灌溉排水学报,2023,42(8):90-97. |
| FAN Liquan,SHI Haibin,YAN Jianwen,et al.局部秋浇条件下冻融期“秋浇-春灌”农田土壤水盐归趋研究[J].灌溉排水学报,2023,42(8):90-97. |
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| 摘要: |
| 【目的】探究河套灌区局部秋浇条件下秋浇和非秋浇（翌年春灌）农田冻融期土壤水盐迁移规律。【方法】基于野外采样观测与室内试验分析，研究了秋浇与非秋浇（翌年春灌）条件下农田冻融期土壤温度变化特征、土壤剖面水分和盐分的变化特征。【结果】在局部秋浇后1周内，秋浇农田表层至深层温度降幅逐渐变大，而春灌农田表层至深层温度降幅逐渐变小。在冻结过程中，秋浇农田0~60 cm土层温度降至0 ℃相比春灌农田早30 d，在消融过程中，秋浇农田0~60 cm土层温度升至0 ℃相比春灌农田晚10 d。秋浇后和冻结期是秋浇农田脱盐的关键时期，0~100 cm土层脱盐47.38%；而春灌农田在冻结、消融阶段分别积盐35.68%、16.87%。在整个冻融期内，秋浇和春灌农田各土层的盐分净通量均为负值，但秋浇农田盐分净通量随着土层深度的增加而增加；而春灌农田盐分净通量随着土层深度的增加先增加后减小。【结论】秋浇和春灌农田之间存在水位差，为水盐迁移提供了驱动力；冻结过程中各土层温度降至0 ℃以下和消融过程中各土层温度升至0 ℃以上存在时间差，导致春灌农田在翌年春灌前呈积盐状态。 |
| 关键词: 局部秋浇；春灌；冻融期；水盐迁移 |
| DOI：10.13522/j.cnki.ggps.2022693 |
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| Analysis of Soil Water and Salt Redistribution during the Freeze-thaw Period in “Autumn Watering-spring Irrigation” under Local Autumn Watering Conditions |
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FAN Liquan, SHI Haibin, YAN Jianwen, LI Xianyue, DOU Xu, QI Qian, LI Huixiang
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1. School of Water Conservancy and Civil Engineering, Inner Mongolia Agricultural University, Hohhot 010018, China;
2. Inner Mongolia Hetao Irrigation District Water Conservancy Development Center Yichang Branch Shahe Canal Water Supply Institute, Bayannaoer 015100, China
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| Abstract: |
| 【Objective】The objective of this study is to investigate the water and salt movement during freeze-thaw period under partial autumn watering conditions in the Hetao Irrigation District. Specifically, the study focuses on comparing the water and salt dynamics between autumn irrigated farmland and non-autumn irrigated farmland (spring irrigated the following year). 【Method】Field sampling observations and laboratory experiments were conducted to analyze the variations in soil temperature, soil moisture, and soil salinity during the freeze-thaw period under autumn watering and non-autumn watering conditions. 【Result】After partial autumn irrigation, the temperature gradually decreased from the surface to the deeper layers in autumn irrigated farmland, while it decreased gradually in spring irrigated farmland. During the freezing process, the soil temperature in the 0~60 cm layer of autumn irrigated farmland dropped below 0 ℃ 30 days earlier than in spring irrigated farmland. In the melting process, the temperature in the 0~60 cm layer of autumn irrigated farmland rose above 0 ℃ 10 days later than in spring irrigated farmland. The desalination of the 0~100 cm soil layer in autumn irrigated farmland occurred mainly after autumn watering and during the freezing period, resulting in a desalting percentage of 47.38%. However, spring irrigated fields experienced salt accumulation of 35.68% and 16.87% during the freezing and melting stages, respectively. Throughout the freeze-thaw period, the net salt flux in each layer of both autumn irrigated and spring irrigated fields was negative, but it increased with soil depth. However, in spring irrigated farmland, the net salt flux initially increased and then decreased with increasing soil depth.【Conclusion】The water and salt migration patterns during the freeze-thaw period were influenced by the water level differences between autumn irrigated and spring irrigated fields. The time difference between the freezing and melting processes led to salt accumulation in spring irrigated fields before the next year’s spring irrigation. These findings provide valuable insights into the water and salt migration dynamics in irrigated and non-irrigated farmland, as well as the optimal development of autumn irrigation and spring irrigation practices under local autumn watering conditions. |
| Key words: local autumn watering; spring irrigation; freeze-thaw period; water-salt migration |
