基于HYDRUS-2D模拟暗管排水条件下分区淋洗对土壤盐分分布的影响

Effects of partition leaching on soil salinity distribution under subsurface drains based on HYDRUS-2D

为探究暗管排水条件下分区淋洗对土壤盐分分布的影响,以沿海盐碱地区为研究区域,选定典型试验地进行现场试验,利用现场试验数据率定了HYDRUS-2D模型参数并验证了模拟暗管排水的准确性,运用验证后的模型模拟了不同分区淋洗情况下的土壤盐分分布.模拟结果表明:HYDRUS-2D能够较好地模拟暗管排水条件下的土壤盐分分布.在暗管排水条件下,非分区淋洗土壤盐分分布均匀性较差,利用分区淋洗可以极大的提高土壤盐分淋洗的均匀性,在5种模拟情景中,F4模拟情景的土壤盐分淋洗均匀性最好,100cm土层的最大与最小含盐量差值仅0.79g/kg。

In order to study on the effect of partition leaching on soil salinity distribution in subsurface drains,field experiment was set up in typical experimental area selected from Coastal saline area.The simulation effect of HYDRUS-2D was verified by experimental data calibration,and salinity distribution of different partition leaching parameters was simulated by the validated model.The simulation results showed that HYDRUS-2D can well simulate the soil salt distribution under the condition of subsurface drains,and under the condition of uniform leaching,the soil salt distribution under the effect of subsurface drains was low in uniformity,the uniformity of soil salt leaching can be greatly improved by partition leaching.Among the 5 simulation scenarios,the soil salt leaching uniformity was the best under the F4 simulation scenario with the partition leaching and irrigation water ration.The difference between the maximum and minimum soil salinity in the 100cm soil layer was only 0.79g/kg.