地表水地下水耦合模型在大型山丘平原交错区的研发与应用

大型山丘平原交错区复杂的自然地理和人类活动特征增加了水文循环研究和水资源评价、管理的难度,地表水地下水耦合模型作为流域/区域水文循环模拟的重要工具,为解决这类大型区域诸多水文水资源问题提供了便利.针对目前地表水地下水耦合模型难以兼顾精度和效率的问题,论文提出了一种新型半松散耦合机制,将三维有限差分地下水流数值模型嵌入半...

A coupled surface water-groundwater model and its application in a large-scale hill-plain region

The complex physical geography and human activities in large-scale hill-plain regions increase the difficulty of hydrologic cycle research and water resources evaluation and management. As an important tool for basin or regional hydrologic cycle simulation, the coupled surface water-groundwater model provides convenience for solving many hydrologic and water resources problems in large regions. To address the conflict between precision and efficiency of modeling, a new semi-loose coupled mechanism was proposed in the study, which embeds the 3D finite difference groundwater flow numerical model into a semi distributed hydrologic model (MODCYCLE). The mechanism abandons the current popular spatial and information conversion method between hydrologic response units (HRUs) and groundwater grid cells, but establishes the spatial association of subbasins and grid cells and the real-time information exchange between surface water and groundwater systems. The model was built and applied in the Sanjiang Plain. The calibration and validation of the model show that it has the ability to simulate the past and predict the future of the hydrologic cycle. Finally, the relationship of surface water and groundwater in the Sanjiang Plain from 2002 to 2014 was analyzed by using the model output. The results show that the increase of precipitation and agricultural irrigation led to an increase of 651 million m³/a of soil water storage in the whole region, but reduced the reserves of surface water and groundwater by 99 million m³/a and 303 million m³/a respectively. The increase of precipitation did not improve the attenuation trend of water resources caused by the rapid increase of water consumption. There were significant differences in the precipitation recharge coefficient and base flow index in different regions, which were the result of the combined action of natural and human factors. The results can provide references for the research of hydrologic cycle and the evaluation of water resources in this region.