豫北平原区干旱情境下地下水开采量多因素响应关系研究

Research on the Multi-Factor Response Relationship of Groundwater Extraction under Drought Conditions in the Northern Henan Plain Area

摘要: 豫北平原干旱灾害频发，叠加长期超采导致地下水位持续下降，已形成多个大型降落漏斗。在气候变化与干旱情景加剧的背景下，传统的单一水量控制指标已难以满足地下水科学供水保障及可持续利用需求。为此，本研究以河南省豫北平原为对象，确定地下水位临界埋深，构建并率定三维地下水流数值模型，结合特大干旱情景，采用拉丁超立方抽样生成100组开采量–补给量组合方案，系统揭示不同干旱条件下地下水位降深与降水量对开采强度的响应特征。在此基础上，构建随机森林模型，实现水位降深、降雨量与开采量的非线性映射。模型测试集决定系数R²达0.9以上，表现出优异的预测精度与泛化能力。研究提出了各子区在不同干旱情景下的地下水可开采量阈值，为豫北平原干旱期地下水科学调度与超采治理提供了定量依据与技术支撑。

Abstract: Frequent drought disasters in the North Henan Plain, combined with long-term over-exploitation, have led to a continuous decline in groundwater levels and the formation of multiple large-scale depression cones. Under the intensifying context of climate change and drought scenarios, traditional single-index control methods for groundwater extraction are no longer sufficient to support scientific water supply security and sustainable groundwater utilization. To address this issue, this study focuses on the North Henan Plain in Henan Province, China. The critical depth of the groundwater level was determined, and a three-dimensional numerical groundwater flow model was developed and calibrated. Under extreme drought scenarios, 100 combinations of groundwater extraction and recharge were generated using Latin Hypercube Sampling. The response characteristics of groundwater level drawdown and precipitation to extraction intensity under various drought conditions were systematically analyzed. Based on this, a Random Forest model was constructed to establish the nonlinear mapping relationship among water level drawdown, precipitation, and extraction volume. The coefficient of determination (R²) for the test set exceeded 0.9, indicating excellent predictive accuracy and generalization capability. The study proposes thresholds for allowable groundwater extraction in different subregions under various drought scenarios, providing a quantitative basis and technical support for scientific groundwater management and over-extraction control during drought periods in the North Henan Plain.