基于SaltMod模型的河套灌区解放闸灌域土壤盐分综合调控措施

为了探究河套灌区解放闸灌域土壤盐分的综合调控措施,以河套灌区解放闸灌域为例,基于SaltMod模型研究了灌溉水矿化度、咸淡水混合比例、排水沟深度以及渠道衬砌水平对作物根层土壤盐分的影响。结果表明:根层土壤盐分随着灌溉水矿化度的增大而增加,1.0 g/L的地表微咸水较适合本研究区灌溉;淡水(黄河水)和地下微咸水(矿化度为2.2 g/L)混合灌溉比为1∶1时,既增加了地下微咸水的利用且地下水埋深下降到2 m左右的相对稳定平衡状态;当排水深度在1.5~2.0 m,渠系利用系数达到0.7时,根层盐分显著降低,适当提高排水深度和渠系水利用系数可以有效减少高矿化度灌溉水对土壤盐分累积的影响。研究结果为河套灌区解放闸灌域制定合理的土壤盐分综合调控措施提供了科学的理论依据。

Study on Comprehensive Control Measures of Soil Salinity in Jiefangzha Irrigation Area of the Hetao Irrigation District Based on SaltMod Model

In order to explore the comprehensive control measures of soil salinity in the Hetao irrigation area,taking the Jiefangzha irrigation area as an example,the effects of irrigation water salinity,the mixing ratio of saline and fresh water,the depth of drainage ditch and the level of channel lining on soil salinity in root zone were studied using the SaltMod model.The results showed that the soil salinity in the root layer increased with the increase of the irrigation water salinity,and the surface brackish water of 1.0 g/L was more suitable for irrigation in this study area;when the mixed irrigation ratio of fresh water(Yellow River water)and underground brackish water(salinity is 2.2 g/L)was 1∶1,the utilization of underground brackish water was increased and the groundwater depth dropped to a relatively stable balance of about 2 m.status;when the drainage depth was between 1.5 and 2.0 m and the canal utilization coefficient reached 0.7,the root layer salinity was significantly reduced.Appropriately increasing the drainage depth and canal water utilization coefficient could effectively reduce the accumulation of soil salt induced by high-salinity irrigation water.The results of this study could provide a scientific theoretical basis for formulating reasonable comprehensive control measures for soil salinity in the Jiefangzha irrigation area of the Hetao Irrigation District.