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How soil texture,channel shape and cross-sectional area affect moisture dynamics and water loss in irrigation channels |
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| Authors: | Zhifan Mu Tianxiao Li Dong Liu Qiang Fu Renjie Hou Qinglin Li Yi Ji Song Cui Mo Li |
| Institution: | 1. School of Water Conservancy and Civil Engineering, Northeast Agricultural University, Harbin, Heilongjiang, China
Key Laboratory of Effective Utilization of Agricultural Water Resources of Ministry of Agriculture, Northeast Agricultural University, Harbin, Heilongjiang, China Heilongjiang Provincial Key Laboratory of Water Resources and Water Conservancy Engineering in Cold Region, Northeast Agricultural University, Harbin, Heilongjiang, China;2. School of Water Conservancy and Civil Engineering, Northeast Agricultural University, Harbin, Heilongjiang, China |
| Abstract: | To enhance the utilization efficiency of farmland irrigation water and reduce the leakage of water conveyance channels, the leakage process of channels was simulated dynamically. The simulated results were compared with data measured in laboratory experiments, and the performance of the model was evaluated. The results indicated that the simulated values of the model were consistent with the observation values, and the R2 values varied between 0.91 and 0.99. In addition, based on the laboratory experiments, a water supply system (Mariotte bottles) and soil box were built using plexiglass. Three influencing factors, namely, the channel form, soil texture and channel cross-sectional area, were varied to observe and calculate the resulting cumulative infiltration amount, infiltration rate and wetting front migration distance. HYDRUS-3D software was used to solve the three-dimensional soil water movement equation under different initial conditions. The results demonstrated that the U-shaped channel was more effective than the trapezoidal channel in increasing the utilization efficiency of the water resources. A U-shaped channel with a small channel cross-sectional area should be adopted and the soil particle size should be prioritized in the construction of water conveyance channels for farmlands. The simulation results were in agreement with the observed results, which indicates that HYDRUS-3D is a reliable tool that can accurately simulate the soil moisture movement in water conveyance channels. The research results can provide a reference for the design and operation of farmland irrigation systems. |
| Keywords: | channel leakage channel shape HYDRUS-3D numerical simulation soil moisture soil texture |