滴灌棉田粉砂壤土的水分特征曲线试验研究

发布时间：2018-05-08 20:35

本文选题：土壤水吸力 + 吸湿曲线　；参考：《新疆农业大学学报》2017年02期

【摘要】：为探究滴灌棉田粉砂壤土土层深度对土壤水分特征曲线的影响,采用张力计法对0~20cm,20~40cm,40~60cm深度土层土壤水分特征曲线测定并分析,选用van Genuchten模型进行拟合。结果表明,随着土层深度的增加,土壤体积含水率随土壤水吸力的变幅降低,变化最快的土层为0~20cm,20~40cm;在同一吸力下,土壤容重越大的土层,相应含水率越大,各土层含水率大小表现为:0~20cm20~40cm40~60cm;不同土层吸湿曲线与脱湿曲线不相同,有滞后现象存在。试验区各土层吸湿与脱湿土壤水分特征曲线均与van Genuchten模型拟合较好,其中40~60cm土层拟合最优,拟合相关系数0.8600~0.9949,实测值与模拟值均方根误差均小于0.01。
[Abstract]:In order to investigate the effect of soil depth on soil moisture characteristic curve in drip irrigation cotton field, the soil moisture characteristic curve of 0 ~ 20 cm ~ (20) ~ (20) ~ (40) ~ (40) cm ~ (-1) ~ (40) ~ (60) cm depth was measured and analyzed by using tensometer method, and the van Genuchten model was used to fit the curve. The results showed that with the increase of soil depth, the volume moisture content of soil decreased with the variation of soil water suction, the fastest change was 0 ~ 20 cm ~ (-1) ~ (20) cm ~ (20) ~ (20) ~ (40) cm, and under the same suction, the higher the bulk density of soil was, the greater the corresponding moisture content was. The moisture content of each soil layer is 20 cm ~ 20 cm ~ (20) ~ 40 cm ~ 40 ~ (60 cm), and the hygroscopic curve and dehumidification curve of different soil layers are different, and the phenomenon of lag exists. The characteristic curves of moisture absorption and dehumidification of each soil layer in the test area were fitted well with van Genuchten model, among which 40~60cm soil layer fitting was the best, the correlation coefficient was 0.8600 ~ 0.9949, and the root mean square error between the measured value and the simulated value was less than 0.01.
【作者单位】：新疆农业大学水利与土木工程学院;
【基金】：国家自然科学基金项目(51469033) 河海大学水文水资源与水利工程科学国家重点实验室开放研究基金(2016490511)
【分类号】：S152.7

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