Understanding the impacts of catchment characteristics on the shape of the storage capacity curve and its influence on flood flows

作者：Gao, Hongkai; Cai, Huayang; Duan, Zheng^*

来源：Hydrology Research: An International Journal , 2018, 49(1): 90-106.

DOI：10.2166/nh.2017.245

• catchment characteristics
• FLEX model
• flooding
• MOPEX
• peak flow
• storage capacity curve

In various conceptual models, the shape parameter (beta) of the storage capacity curve, representing the non-linear relationship between relative soil moisture and runoff, determines runoff yield given certain circumstances of rainfall and antecedent soil moisture. In practice, beta is typically calibrated for individual catchments and for different purposes, which limits more systematic understanding and also prediction in ungauged basins. Moreover, its regionalization and linkage to catchment characteristics is also not well understood, especially in relation to large-sample datasets. In this study, we used 404 catchments in the USA to explore beta regionalization and attributes in relation to key catchment characteristics: elevation, slope, depth-to-bedrock, soil erodibility, forest cover, urban area, aridity index, catchment area, and stream density. We found a clear regionalized pattern of beta, coherent with topography. Comparisons between beta and various features demonstrated that slope has the largest impact. Land-cover, soil, geology, and climate also have an impact, but with lower correlation coefficients. This finding not only reveals spatial variation in beta, but also deepens our understanding of its linkage to catchment features and flood flows. Moreover, the results provide a useful reference for decision-makers for flood prevention and mitigation.

• 出版日期2018-2
• 单位中山大学