Arizona Base-flow Index (HUC-8)

This dataset provides long-term estimates of the Base-Flow Index (BFI) for all HUC-8 basins in Arizona from 1980 to 2020. BFI, representing the groundwater-derived portion of streamflow, was computed at gauged sites using recursive digital filtering and then regionalized to ungauged basins through an XGBoost regression framework. Climatic and topographic variables served as primary predictors to capture spatial controls on base-flow generation across Arizona’s diverse hydroclimatic gradients. The resulting product offers consistent, basin-scale BFI estimates suitable for hydrologic assessment, groundwater–surface water interaction studies, and evaluation of streamflow-associated recharge in data-limited regions.

本数据集提供了1980年至2020年间美国亚利桑那州所有8位水文单元（Hydrologic Unit Code 8, HUC-8）流域的基流指数（Base-Flow Index, BFI）长期估算结果。基流指数代表径流中由地下水补给的占比，本研究先通过递归数字滤波法在实测径流站点完成基流指数的计算，随后借助极限梯度提升（XGBoost）回归框架将估算结果区域化至无实测资料流域。研究选取气候与地形变量作为核心预测因子，以捕捉亚利桑那州多样水文气候梯度下基流形成的空间控制机制。最终生成的数据集提供了一致性的流域尺度基流指数估算结果，可适用于资料匮乏区域的水文评估、地下水-地表水交互作用研究，以及径流相关补给量的评估工作。