石津灌区地下水潜在补给量时空分布及影响因素分析

摘要

采用区域水量平衡模型INFIL3．0，结合GIS和RS技术，研究了石津灌区净入渗水量和潜在补给系数的时空分布，并对主要影响因素进行了分析。对原模型进行了改进，考虑了植被覆盖度逐月变化与灌溉量时空间分布的影响，提高了其在灌区的适用性。结果显示，石津灌区净人渗水量及潜在补给系数具有明显的时空变异性，主要取决于根区层土壤的水量均衡过程。空间上，补给主要发生在灌溉区域，渠灌区、井渠灌区和井灌区的潜在入渗补给系数分别为0．21、0．16和0．09；时间上，净人渗水量峰值出现在5月份，灌溉水是灌区地下水主要的补给源。由灌区各栅格的空间分析和剖面分析表明，灌区存在较大的节水潜力。%In this paper, combined with G1S and RS, the 1NFIL3.0 model which is based on the regional water balance to evaluated potential recharge, is used to calculate the temporal and spatial distribution of net infiltration and potential recharge coefficient in the Shijin Irrigation District, and the main factors influencing potential recharge are analyzed. The model is modified to improve its applicability and realibility in irrigation area. The results show that the net infiltration and potential recharge coefficient have obviously space and temperal variability, depending on water balance process of the root zone. The potential recharge mainly occurred in the irrigated area. The potential recharge coefficient is 0.21, 0.16 and 0.09 for canal, well and well-canal irrigation area, respectively. The peak of the net infiltration emerged in May and irrigated water are the main sources for groundwater recharge. The spatial and profile analysis of the potential recharge indicates that there is a large water-saving potential in the Shijin Irrigation District.