Rainfall–Runoff Processes and Modelling in Regions Characterized by Deficiency in Soil Water Storage

• Published in: Water (Basel) Vol. 11; no. 9; p. 1858
• Main Authors: Shi, Pengfei, Yang, Tao, Xu, Chong-Yu, Yong, Bin, Huang, Ching-Sheng, Li, Zhenya, Qin, Youwei, Wang, Xiaoyan, Zhou, Xudong, Li, Shu
• Format: Journal Article
• Language: English
• Published: Basel MDPI AG 01.09.2019
• Subjects: dual distribution curves of variable soil water storage capacity; Environmental aspects; Flood forecasting; Heterogeneity; Hydrologic models; Hydrology; Infiltration (Hydrology); Infiltration capacity; large deficiency in soil water storage; Modelling; Moisture content; Rain and rainfall; Rainfall; rainfall–runoff model; rainfall–runoff process; Reservoirs; Runoff; Simulation; Soil moisture; Soil structure; Soil water; Soil water storage; Storage capacity; Topography; vertical and horizontal soil heterogeneity; Vertical orientation; Water storage; Watersheds; China; Sacramento California; United States > US
• ISSN: 2073-4441; 2073-4441
• DOI: 10.3390/w11091858

The partial runoff is complicated in semi-arid and some semi-humid zones in terms of what the runoff generates in partial vertical positions. The partial runoff is highlighted by horizontal soil heterogeneity as well. How to identify the partial runoff and develop a variable threshold for runoff generation is a great difficulty and challenge. In this work, the partial runoff is identified by using a variable active runoff layer structure, and a variable soil water storage capacity is proposed to act as a threshold for runoff generation. A variable layer-based runoff model (VLRM) for simulating the complex partial runoff was therefore developed, using dual distribution curves for variable soil water storage capacity over basin. The VLRM is distinct in that the threshold for runoff generation is denoted by variable soil water storage capacity instead of infiltration capacity or constant soil water storage capacity. A series of flood events in two typical basins of North China are simulated by the model, and also by the Xinanjiang model. Results demonstrate that the new threshold performs well and the new model outperforms the Xinanjiang model. The approach improves current hydrological modelling for complex runoff in regions with large deficiencies in soil water storage.