| 引用本文: | 李 勇,李 林,王 峰,等.冬灌结合少量春灌条件下南疆棉田休闲期适宜冬灌定额研究[J].灌溉排水学报,2022,41(12):10-17. |
| LI Yong,LI Lin,WANG Feng,et al.冬灌结合少量春灌条件下南疆棉田休闲期适宜冬灌定额研究[J].灌溉排水学报,2022,41(12):10-17. |
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| 摘要: |
| 【目的】探究冬灌结合少量春灌条件下南疆棉田休闲期土壤水盐运移规律，确定冬灌结合春灌条件下的适宜冬灌定额。【方法】基于田间试验，监测不同时期0~100 cm土层水、盐指标，探讨不同冬灌（0、600、1 200、1 800、2 400、3 000、3 600 m3/hm2）结合少量春灌（300 m3/hm2）对南疆棉田休闲期土壤水盐运移及盐分淋洗效率的影响。【结果】①冬灌具有一定的储水效应，冬灌初期各处理土壤含水率均大幅度增加，0~30 cm土层含水率的整体增幅最大；春灌前，各处理土壤含水率均大幅度下降，其中冬灌600 m3/hm2及未冬灌处理0~100 cm土层含水率低于冬灌前；补充春灌后，对于冬灌定额达1 800 m3/hm2及以上的处理，0~30 cm土层平均质量含水率均在15.66%以上。②水是盐分运移的载体，冬灌初期土壤盐分有效淋洗深度随冬灌定额的升高而逐渐增大，当冬灌水量达到2 400 m3/hm2时，盐分有效淋洗深度可达100 cm；春灌前，经过长期的休闲期土壤蒸发，各处理均出现不同程度的返盐现象，其中未冬灌处理土壤表层返盐最为剧烈；补充春灌300 m3/hm2后，各处理土壤剖面盐分得到再次淋洗，0~30 cm土层含盐量整体降幅较大。③经历整个休闲期后，0~30 cm和0~100 cm土层平均脱盐率均以冬灌2 400 m3/hm2结合春灌300 m3/hm2处理为最高。④春灌后，冬灌2 400 m3/hm2结合春灌300 m3/hm2处理0~30 cm土层平均电导率为1.40 mS/cm，0~10 cm土层电导率为1.30 mS/cm，对应全盐量分别为3.65、3.32 g/kg，低于棉花出苗盐分适宜值（3.7 g/kg）。【结论】综合考虑节水、脱盐效应以及春灌后0~30 cm土层土壤含水率和含盐量，灌水定额2 400 m3/hm2是本地区冬灌结合少量春灌（300 m3/hm2）条件下的最优冬灌定额。 |
| 关键词: 冬灌；春灌；水盐运移；盐分淋洗；冬灌定额 |
| DOI：10.13522/j.cnki.ggps.2022198 |
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| Suitable Irrigation Scheduling in Winter-spring Fallow Period for Leaching Salt Out of Root Zone of Cotton in Southern Xinjiang |
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LI Yong, LI Lin, WANG Feng, LIU Liang, LUO Xijuan, WANG Xingpeng
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1. College of Water Conservancy and Architecture Engineering, Tarim University, Alaer 843300, China;
2. Institute of Farmland Irrigation, Chinese Academy of Agricultural Sciences/
Key Laboratory of Crop Water Use and Regulation, Ministry of Agriculture and Rural Affairs, Xinxiang 453002, China
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| Abstract: |
| 【Objective】 Soil salinity is an abiotic challenge facing agricultural production in Xinjiang. One solution to ameliorate the impact of soil salinity is to leach the salt out of the root zone in winter-spring period after harvest but before planting. The purpose of this paper is to experimentally study the suitable irrigation scheduling to achieve that goal. 【Method】The experiment was conducted in a field where irrigation amount in the winter varied from 0 to 3 600 m3/hm2, combined with a spring irrigation with the amount 300 m3/hm2. In each treatment, we measured the change in water and salt contents at different soil depths.【Result】①The winter irrigation affected water storage in the soil, especially in the early stage and in the top 0~30 cm soil layer where the irrigation significantly increased the soil moisture content, regardless of the irrigation amount. The increase was followed by a decline until commencement of the spring irrigation. The soil moisture content in 0~100 cm soil layer irrigated by 600 m3/hm2 of water in the winter was lower than that before the irrigation; a supplementary spring irrigation boosted soil moisture content in the 0~30 cm soil layer by more than 15.66% compared to that with only one winter irrigation at 1 800 m3/hm2. ②In the early stage after the winter irrigation, salt leaching depth increased with the increase in irrigation amount; when the irrigation amount was 2 400 m3/hm2 or above, the leaching depth was as deep as 100 cm. However, the prolonged drying season prior to the spring irrigation drove salt ascending, regardless of winter irrigation amount. The supplementary spring irrigation leached salt, especially from the 0~30 cm soil layer where the desalinization was most significant. ③Combining a 2 400 m3/hm2 winter irrigation and a 300 m3/hm2 spring irrigation desalinated the 0~30 cm and 0~100 cm soil layers most efficiently. ④After the spring irrigation, the average electric conductivity of the 0~30 cm and 0~10 cm soil layer was 1.40 mS/cm and 1.30 mS/cm, respectively, and the associated total salt content were 3.65 and 3.32 g/kg, respectively, lower than the critical salt content for cotton emergence (3.7 g/kg).【Conclusion】Considering water saving, desalination and soil water in the 0~30 cm soil layer after the spring irrigation, irrigating 2 400 m3/hm2 in winter combined with a 300 m3/hm2 irrigation in spring is optimal for cotton growth in the studied region. |
| Key words: winter irrigation; spring irrigation; water salt transport; salt leaching; winter irrigation quota |
