| 引用本文: | 王炳尧,韦伟,刘立超,等.直插式地下滴灌土壤湿润体特征值变化规律及灌溉效果分析[J].灌溉排水学报,2019,38(4):1-10. |
| WANG Bingyao,WEI Wei,LIU Lichao,et al.直插式地下滴灌土壤湿润体特征值变化规律及灌溉效果分析[J].灌溉排水学报,2019,38(4):1-10. |
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| 摘要: |
| 【目的】了解2种典型干旱区土壤（砂土、砂黏土）中直插式地下滴灌的灌水效果。【方法】以实测的土壤湿润锋在垂直向上、向下和水平3个方向的运移距离为基础，建立了土壤湿润锋运移距离与直插式地下滴灌滴头流速和灌水时间之间的函数关系，依据此量化关系结合土壤含水率求得了直插式地下滴灌的微灌技术参数，并评价了直插式地下滴灌在干旱区砂土、砂黏土中的灌水效果。【结果】在2种土质条件下，湿润锋不同方向上的运移距离与滴头流速和灌水时间之间的量化关系式R2＞0.95，验证方程R2＞0.95，表明模型可行；在砂土中，灌溉水储存系数、灌水均匀系数及土壤湿润比均小于0.6，而在砂黏土中均高于0.8，表明直插式地下滴灌在砂土中灌水效果比砂黏土差。【结论】幂函数可准确描述砂土、砂黏土中直插式地下滴灌湿润峰运移距离、滴头出流速度和灌水时间之间的关系；垂直向上湿润距离与滴头流速负相关，与灌水时间正相关，水平与向下湿润距离与流速、灌水时间均正相关；在本试验条件下，流速为1.25 L/h灌水效果最好。 |
| 关键词: 干旱区； 直插式地下滴灌； 湿润体； 湿润锋； 运移距离； 微灌技术参数 |
| DOI：10.13522/j.cnki.ggps.20180441 |
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| Water Movement and Its Potential for Uptake by Roots under Plug-in Subsurface Drip Irrigation |
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WANG Bingyao, WEI Wei, LIU Lichao, WANG Zengru
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1.Northwest Institute of Eco-environment and Resources，Chinese Academy of Science， Lanzhou 730000， China; 2.University of Chinese Academy of Sciences, Beijing 100049, China; 3. Ningxia Agricultural Comprehensive Development Office, Yinchuan 750001, China
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| Abstract: |
| 【Objective】Plug-in subsurface drip irrigation is an technique able to deliver water and nutrients to desirable root zones. The objective of this paper is to investigate its efficacy in modulating water movement and its subsequent uptake by plant roots. 【Method】The experiment was conducted in a sandy soil and a sandy clay soil, typical in northwest China. During the experiment, we measured advances of the wetting fronts in both vertical and horizontal directions and established their relationship with flow rate and irrigation duration, from which we calculated the parameters in irrigation design.【Result】For both soils, there was a good relationship between wetting-front advance in all directions with flow rate and irrigation duration, with a determinant coefficient of R2 = 0.95. The storage coefficient of the irrigation water, the irrigation uniformity coefficient and soil wetting ratio in the sandy soil were all less than 0.6, while their associated values in the sand clay soil were larger than 0.8, indicating that the plug-in subsurface drip irrigation was less efficient in the sandy soil than in the sandy clay soil. 【Conclusion】The advance of the wetting-front increased with flow rate and irrigation duration in a power-law, with the determinant coefficients being 0.95. The upward advance of the wetting-front was negatively related to the flow rate but positively to the irrigation duration. In contrast, the moving distances of the wetting font in both horizontal and downward vertical direction increased with both flow rate and irrigation duration. In our experiment the flow rate of 1.25 L/h was most effective. |
| Key words: arid area; plug-in subsurface drip irrigation; wetting zone; wetting front; moving distance; micro irrigation parameters |
