Acta Geographica Sinica ›› 2023, Vol. 78 ›› Issue (7): 1627-1640.doi: 10.11821/dlxb202307005

• Academician Forum • Previous Articles     Next Articles

Hydrological mechanism and disaster-causing effects of subsurface stormflow

CUI Peng1,2(), ZHANG Guotao1, ZHANG Chendi1   

  1. 1. Institutes of Geographic Sciences and Natural Resources Research, CAS, Beijing 100101, China
    2. China-Pakistan Joint Research Center on Earth Sciences, Islamabad 45320, Pakistan
  • Received:2023-03-23 Revised:2023-07-07 Online:2023-07-25 Published:2023-08-01
  • Supported by:
    National Natural Science Foundation of China(41941017);National Natural Science Foundation of China(42201086);National Key R&D Program of China(2022YFC3002902);The National Postdoctoral Program for Innovative Talents(BX20220293)

Abstract:

Subsurface stormflow is a special form of subsurface flow in the vadose zone of steep slopes in mountainous and hilly regions, and it is also one of the most important runoff generation mechanisms in the process of flash flood formation. However, the systematic summary on the scientific connotation, mechanisms, and disaster-causing characteristics of the subsurface stormflow in current research is very rare and this limits the development of the theoretical system of runoff generation, routing, and modeling methods of flash floods. Herein, we clarify the scientific connotation and definition of subsurface stormflow based on the division of the development periods of the subsurface stormflow research around the world as well as the analysis of physical processes for the runoff generation. Meanwhile, three physical conditions for the occurrence of subsurface stormflow, together with their influences on the nonlinear response process, are highlighted. The influences of the subsurface stormflow on the dynamic development of flash floods, landslides, and debris flow hazards are analyzed and summarized. Finally, three key research directions are proposed: water transport processes and hydrological connectivity mechanism of the macropores in the vadose zone, processes and mechanisms of water exchange at the geotechnical channel interfaces inside the slopes, and the formation mechanism for flash flood from multiple runoff generation processes with complex slope topography conditions. This work can provide new research perspectives for the formation mechanism and hydrological theoretical framework of flash floods in complex mountainous regions, and better support the national scientific and technological needs for flash flood forecast as well as disaster prevention and mitigation.

Key words: subsurface stormflow, runoff generation mechanism, vadose zone, flash flood