| 引用本文: | 张锦华,李明思,韩寒,等.非饱和土壤中大孔隙流的影响因素研究[J].灌溉排水学报,0,():-. |
| ZHANG Jinhua,LI Mingsi,HAN Han,et al.非饱和土壤中大孔隙流的影响因素研究[J].灌溉排水学报,0,():-. |
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| 摘要: |
| 【目的】分析非饱和土壤中大孔隙流现象的影响因素及影响特点，为大孔隙流理论的生产化应用提供帮助。【方法】在装有粉砂壤土的土槽中人工造出直径4 mm的通地表和不通地表的孔隙进行滴灌试验，设置3种灌水量：50 L、60 L、70 L；3种孔隙深度（长度）：50 cm、60 cm、70 cm；3种土壤初始含水率：5.7%、9.9%、13.3%。通过测定孔隙不同深度处的孔壁土壤含水率及相应深度处基质流区的含水率，并计算其相应的基质吸力，分析孔隙中出现大孔隙流的概率。【结果】结果表明，土壤中出现大孔隙流的现象具有一定的随机性，孔隙上部（0~30 cm）出现大孔隙流的概率在2.08%~7.14%之间，下部（40~70 cm）出现大孔隙流的概率在14.58%~19.05%之间，上部出现大孔隙流的概率小于下部出现大孔隙流的概率；通地表孔隙出现大孔隙流的概率（13.04%）小于不通地表孔隙出现大孔隙流的概率（27.54%）；3种影响因素对出现大孔隙流的影响程度为：孔隙深度（长度）最大，初始含水率次之，灌水量最小。【结论】非饱和土壤中，孔隙深度（长度）对出现大孔隙流的概率影响较大；大孔隙流现象通常出现在孔隙的下半部分。 |
| 关键词: 非饱和土壤;大孔隙流;基质吸力;农田排水;土壤水分运动 |
| DOI： |
| 分类号:S152 |
| 基金项目:国家自然科学基金重大项目(编号51790533) |
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| Study of Influence Factors on the Macropore Flow in Unsaturated Soil |
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ZHANG Jinhua, LI Mingsi, HAN Han, LIU Xingshuang, XU Qiang, LAN Mingju
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College of Water Resources and Architectural Engineering,Shihezi University
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| Abstract: |
| 【Objective】The factors of influencing the macropore flow in unsaturated soil were analyzed in this piper as well as their influencing pattern, which favorable to the macropore flow theory to be used practicably.【Method】In soil tanks full with fine sandy loam, the drip irrigation tests were conducted after two kinds of covered macropores with 4 mm diameter were made artificially in soil, which some of macropores were linking up with soil surface, and others were covered by soil. Three kinds of influencing factors that irrigation volumes: 50 L, 60 L, 70 L; pore depths (length): 50 cm, 60 cm, 70 cm; and initial soil water contents: 5.7%, 9.9%, 13.3%, were set in the tests. The probability of macropore flow developed in the pore space was analyzed by determining the water content of the pore wall soil at different depths of the pore space and the water content of the matrix flow zone at the corresponding depth, and calculating its corresponding matrix suction.【Results】The results show that the occurrence of macropore flow in soils was somewhat random and not necessarily continuous. The probability of macropore flow emerged in the upper part of the pore (0~30 cm) ranged from 2.08% to 7.14%, and that emerged in the lower part of the pore (40~70 cm) ranged from 14.58% to 19.05%, which it could be believed that the probability of macropore flow in the upper part was less than that in the lower part. The probability of macropore flow for the pores linked up with soil surface (13.04%) was less than that for the pores covered by soil (27.54%). The impact degree of the three influencing factors on the macropore flow developing was: pore depth (length) was the largest, initial water content was the second, and irrigation volume was the smallest.【Conclusion】In unsaturated soils, the pore depth (length) has a greater effect on the probability of macropore flow; macropore flow phenomenon usually occurs in the lower part of the pore. |
| Key words: Unsaturated soil; Macropore flow; Matrix suction; Farmland drainage; Soil physics |
