| 引用本文: | 张丽,焦平金,董勤各,等.暗管间距和埋深对田间水盐运移的影响[J].灌溉排水学报,0,():-. |
| ZHANG li,JIAO Pingjin,DONG Qin’ge,et al.暗管间距和埋深对田间水盐运移的影响[J].灌溉排水学报,0,():-. |
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| 摘要: |
| 摘 要：【目的】研究河套灌区漫灌模式下田间尺度暗管间距和埋深对土壤水盐运移特征的影响。【方法】基于田间监测数据率定验证HYDRUS-2D模型，并模拟暗管埋深1.5 m下5种暗管间距（5、15、25、50、100 m）与暗管间距25 m下5种暗管埋深（0.6、1.0、1.5、2.0、2.5 m）下的排水排盐量和土壤剖面水盐时空分布特征。【结果】（1）模型模拟水盐变化的精度较高，土壤剖面水分和盐分模拟结果的决定系数R2分别为0.81和0.71，均方根误差RMSE分别为0.038和0.026，纳什系数NSE分别为0.93和0.86。（2）累积排水量和累积排盐量随暗管间距减小和暗管埋深增加而增加，暗管埋深为1.5 m时，暗管间距为5 m的排水总量较暗管间距为100 m处理增加了4.96倍，排盐总量增加了5.06倍；暗管间距为25 m时，暗管埋深为2.5 m的排水总量较暗管埋深为0.6 m处理增加了64.24倍，排盐总量增加了60.08倍。（3）土壤剖面含水率在排水期随暗管间距减小和暗管埋深增加而降低，土壤剖面含水率降幅随时间增加而减小；土壤剖面含盐量在非排水期随暗管间距减小和暗管埋深增加而降低，土壤剖面含盐量降幅随时间增加而增大。（4）水平方向，土壤含盐量在非排水期随距暗管水平距离的增加而增大，土壤含盐量增幅随暗管间距减小和暗管埋深增大而减小。暗管埋深1.5 m时，暗管间距5 m处理与暗管间距100 m处理土壤含盐量差异从暗管处的26.67%增加到暗管中间的39.88%，暗管间距25 m时，暗管埋深0.6 m处理与暗管埋深2.5 m处理土壤含盐量差异从暗管处的30.56%增加到暗管中间的50.39%；垂直方向，土壤含水率随土层深度增加呈先增大后减小的“镰刀”状变化；土壤含盐量排水初期随土层深度的增加而增大，非排水期随土层深度的增加而减小。【结论】减少暗管间距和增加暗管埋深可有效提高暗管排水排盐量并降低排水期的土壤剖面蓄水量和非排水期的土壤剖面积盐量，初步认为暗管间距在15~50 m，暗管埋深在1.0~2.0 m范围内作为河套灌区的暗管排水布设参数较为合适。 |
| 关键词: 暗管排水;水盐运移;暗管间距;暗管埋深;HYDRUS-2D |
| DOI： |
| 分类号:S276 |
| 基金项目:国家自然科学(52179054) |
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| Effects of Subsurface Pipe Spacing and Burial Depth on Water and Salt Transport in Field |
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ZHANG li1,2, JIAO Pingjin3, DONG Qin’ge4,5, TAO Yuan3
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1.College of Water Resource and Architectural Engineering, Northwest A &2.F University;3.Institute of Water Conservancy, China Institute of Water Resources and Hydropower Research, Beijing;4.Institute of Soil and Water Conservation, Northwest A &5.F University, Yangling
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| Abstract: |
| Abstract: 【Objective】 The effects of different spacing and burial depth of subsurface pipe at field scale on soil water and salt transport characteristics under flood irrigation in the irrigation area of Hetao were studied. 【Methods】Based on the field monitoring data, the HYDRAS-2D model was calibrated and validated, and the temporal and spatial changes of drainage and salt discharge and soil profile water and salt distribution were simulated under the influence of five subsurface pipe spacing (5, 15, 25, 50 and 100 m) under 1.5 m of subsurface pipe buried depth and five subsurface pipe buried depths (0.6, 1.0, 1.5, 2.0 and 2.5 m) under 25 m of subsurface pipe spacing. 【Results】 (1) The accuracy of the model simulation of water and salt change is high, and the coefficients of determination R2 of soil profile moisture and salinity simulation results are 0.81 and 0.71, the RMSE error is 0.038 and 0.026, respectively, and the Nash coefficient NSE is 0.93 and 0.86, respectively. (2) When the buried depth of the subsurface pipe was 1.5 m, the total drainage of the subsurface pipe spacing of 5 m increased by 4.96 times and the total amount of salt discharged increased by 5.06 times compared with the treatment of 100 m of subsurface pipe spacing, and when the buried pipe spacing was 25 m, the total drainage of the buried pipe with a buried depth of 2.5 m increased by 64.24 times compared with the buried depth of the subsurface pipe of 0.6 m, and the total amount of salt discharged increased by 60.08 times. (3) The moisture content of soil profile decreased with the decrease of subsurface pipe spacing and the increase of buried depth of subsurface pipe during the drainage period, and the decrease of soil profile moisture content decreased with the increase of time. The salt content of soil profile decreased with the decrease of subsurface pipe spacing and the increase of buried depth of subsurface pipe in the non-drainage period, and the decrease of soil profile salt content increased with time. (4) In the horizontal direction, the soil salt content increased with the increase of the horizontal distance from the subsurface pipe during the non-drainage period, and the increase of soil salt content decreased with the decrease of the subsurface pipe spacing and the increase of the buried depth of the subsurface pipe. When the buried depth of the subsurface pipe was 1.5 m, the difference in soil salt content between the treatment of 5 m of the subsurface pipe spacing and the treatment of 100 m of the subsurface pipe increased from 26.67% at the subsurface pipe to 39.88% in the middle of the subsurface pipe, and the difference in soil salinity between the buried depth of 0.6 m and the buried depth of the subsurface pipe at 2.5 m increased from 30.56% at the subsurface pipe to 50.39% in the middle of the subsurface pipe when the buried depth was 25 m. In the vertical direction, the soil moisture content changed in the shape of a "sickle" with the increase of soil depth. The initial stage of soil salinity drainage increases with the increase of soil depth, and the non-drainage period decreases with the increase of soil depth. 【Conclusions】 Reducing the spacing of subsurface pipes and increasing the buried depth of subsurface pipes can effectively increase the drainage salt discharge of subsurface pipes and reduce the soil profile water storage in the drainage period and the salt amount of soil profile area in the non-drainage period. |
| Key words: subsurface pipe drainage; water and salt transport; subsurface pipe spacing; subsurface pipe buried deep; HYDRUS-2D |
