基于地表水与地下水分割校正的漓江流域水供给服务时空格局研究

喀斯特区域水循环过程与其他地区存在显著区别，其水供给服务也具有独特的空间分布特征。然而，目前针对喀斯特地区产水量的时空变化研究较少考虑喀斯特生态系统的特殊性，导致产水量的空间模拟结果存在一定偏差。根据喀斯特地貌形态和地下水补径排泄特征提出了一种产水量分割方法，并基于水量平衡原理建立了地表水与地下水分割校正概念模型。选取喀斯特山区典型区域漓江流域为研究区，通过上述方法校正了InVEST模型产水量模拟结果，从栅格、地貌分区和子流域3个尺度分析了漓江流域2000—2020年产水量校正前与校正后时空分布格局。研究结果表明：(1)漓江流域2000—2020年InVEST模型产水量呈现先减后增再减的趋势，水供给服务空间分布格局为北高南低。产水深度在岩溶区和非岩溶区几乎没有差异，但在岩溶区内部差异明显：裸露型岩溶区产水深度高于覆盖型和埋藏型，峰林平原产水深度高于峰丛洼地。子流域分区平均产水深度排序为漓江上游区>漓江中游区>恭城河区>荔浦河区>漓江下游区。(2)利用地表与地下水分割校正后，水供给服务空间分布格局为四周高于中部，西北部高于东南部。非岩溶区产水深度明显高于岩溶区，埋...

Spatio-temporal patterns of water supply service in the Li River Basin based on correction method of surface water and groundwater partitioning

The hydrological cycle process in karst landscapes is significantly different from other regions, and the water supply service of the karst ecosystem is also unique. However, the current studies on the spatial and temporal variation of water yield in karst areas seldom take into account the special characteristics of karst ecosystems, resulting in some biases in the spatial simulation results of water yield. In this article, a water yield partitioning method was proposed based on the characteristics of karst landscape, and a conceptual model for water yield correction was established by combining the water balance method and groundwater recharge and discharge characteristics. We selected the Li River Basin, a typical karst area, as the study area, calibrated the water yield simulation results of the InVEST model by the above method, and compared the spatial and temporal distribution patterns of water yield in the Li River Basin before and after calibration from 2000 to 2020 at three scales:raster cell, karst geomorphic unit, and sub-basin. The results showed that:(1) water yield simulated with the InVEST with a spatial expression of model in the study area presented a trend of decreasing, increasing, and then decreasing from 2000 to 2020, high in the north and low in the south. Water yield hardly differed between the karst and non-karst areas, but varied more within the karst areas. Specifically, the water yield decreased in the order of bare, covered, and buried karst with the exposure of water-bearing rock formations and in the order of plain, depression, and peak-cluster with the change of geomorphology. The water yield decreased in the order of upstream region of Li River, midstream region of Li River, Gongcheng River region, Lipu River region and downstream region of Li River. (2) The water supply services corrected with the water yield partitioning method were higher in the northwest than that in the southeast, and higher in the surrounding than that in the middle. The water yield showed significant differences between karst and non-karst areas, and also within different karst units. Specifically, the water yield decreased in the order of buried, covered, and bare karst with the exposure of water-bearing rock formations and in the order of plain, peak-cluster, and depression with the change of geomorphology. The water yield decreased in the order of midstream region of Li River, upstream region of Li River, Gongcheng River region, Lipu River region and downstream region of Li River. (3) Compared with the results of the InVEST model, the water yield corrected with the water yield partitioning method was closer to the measured runoff values, and the spatial and temporal distribution of corrected water yield was more accurate in quantitatively assessing the available water resources in the karst region. This study can provide a scientific and reasonable data basis for water resources protection decision-making and ecological compensation mechanism establishment.