基于水文随机方法的大尺度径流空间插值图化研究——淮河流域蚌埠以上区间为例

Mapping Runoff Based on Water Balance:A Case Study of the Huaihe River Basin above Bengbu

跨越不同时空尺度水文径流时空分异性及其图化问题的研究是当前国际地理水文科学研究的热点前沿。本文针对中国湿润流域年平均径流特点,探讨了基于地理相关关系的水文随机方法(Hydro-Stochastic)在大尺度流域上应用的可行性。在淮河流域蚌埠以上区间开展径流空间插值实验,通过对流域出口流量在空间随机场内的分解生成研究区内10km×10km分辨率产流分布图,以及以1km长度为基本单元的河道内径流量图。该方法在描述径流空间分异性的过程中,综合了水文学、地貌学、地理学的特点,以地统计空间插值方法为基础,结合了水量平衡约束以及数据不确定性分析理论,最终输出不同形式的径流空间分异结果。分析表明,径流插值结果能够很好的反映流域内产流的空间分布特征,并满足河道上下游的水量平衡关系。该方法避免了水文模型的复杂性,描述径流时不依赖气象资料,可以方便的在广大地区推广使用。

This presentation describes a hydro-stochastic approach method for producing choropleth maps of average runoff and computing mean discharge along the main river network. The approach applied to mean annual runoff is based on geostatistical interpolation procedures coupled with water balance and data uncertainty analyses. It is proved by an application in the Huaihe River Basin above Bengbu, a typical basin in China. By disaggregating the mean annual streamflow measured at the outlet of a basin to estimate water depths on elements of an exact partition of this basin, it works out gridded runoff yield maps with a resolution of 10 km × 10 km and the discharge map along the river with a 1 km basic unit in length. These results are consistent with water balance.