Improvement of LCM model and determination of model parameters at watershed scale for flood events in Hongde Basin of China

Water Science and Engineering. 2017;10(1):36-42 DOI 10.1016/j.wse.2017.03.006

 

Journal Homepage

Journal Title: Water Science and Engineering

ISSN: 1674-2370 (Print); 2405-8106 (Online)

Publisher: Elsevier

Society/Institution: Hohai University

LCC Subject Category: Technology: Hydraulic engineering: River, lake, and water-supply engineering (General)

Country of publisher: Netherlands

Language of fulltext: English

Full-text formats available: PDF, HTML

 

AUTHORS

Jun Li (Key Laboratory of Mountain Hazards and Earth Surface Processes, Institute of Mountain Hazards and Environment, Chinese Academy of Sciences, Chengdu 610041, China)
Chang-ming Liu (Key Laboratory of Water Cycle and Related Land Surface Processes, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China)

EDITORIAL INFORMATION

Double blind peer review

Editorial Board

Instructions for authors

Time From Submission to Publication: 50 weeks

 

Abstract | Full Text

Considering the fact that the original two-parameter LCM model can only be used to investigate rainfall losses during the runoff period because the initial abstraction is not included, the LCM model was redefined as a three-parameter model, including the initial abstraction coefficient λ, the initial abstraction Ia, and the rainfall loss coefficient R. The improved LCM model is superior to the original two-parameter model, which only includes r and R, where r is the initial rainfall loss index and can be calculated with λ using the Soil Conservation Service curve number (SCS-CN) method, with r=1/(1+λ). The trial method was used to determine the parameter values of the improved LCM model at the watershed scale for 15 flood events in the Hongde Basin in China. The results show that larger r values are associated with smaller R values, and the parameter R ranges widely from 0.5 to 2.0. In order to improve the practicability of the LCM model, r=0.833 with λ=0.2 is reasonable for simplifying calculation. When the LCM model is applied to arid and semi-arid regions, rainfall without yielding runoff should be deducted from the total rainfall for more accurate estimation of rainfall-runoff.