SCIENTIA GEOGRAPHICA SINICA ›› 2015, Vol. 35 ›› Issue (4): 483-490.doi: 10.13249/j.cnki.sgs.2015.04.483

• Orginal Article • Previous Articles     Next Articles

The Impact of Variation in Rainfall on Runoff in the Dongjiang River Basin

Jie LIU1,2, Xiao-hong CHEN2(), Zhen-cheng XU1, Qing-wei GUO1, Zhi-feng XIAO3, Zhao-li WANG4, Gen-yi WU1,5   

  1. 1.South China Institute of Environmental Sciences, MEP, Guangzhou, Guangdong 510655,China
    2.Department of Water Resources and Environment, Sun Yat-sen University, Guangzhou, Guangdong 510275,China
    3.Department of Geo-informatics & Survey Engineering, South China Agricultural University, Guangzhou, Guangdong 510642,China
    4.School of Civil Engineering and Transportation, South of China University of Technology, Guangzhou, Guangdong 510641,China
    5. Department of Environmental Science and Engineering, Hunan Agricultural University, Changsha, Hunan 410128, China
  • Received:2014-02-21 Revised:2014-05-08 Online:2015-04-20 Published:2015-04-20

Abstract:

The impact of rainfall variation on watershed hydrological process is an issue of great deliberation in geographical and environmental sciences. In this article, a comprehensive watershed model—The hydrological simulation program FORTRAN(HSPF) was set up and calibrated for the Dongjiang River basin in China, and was repeatedly run with various rainfall scenarios generated by the daily rainfall stochastic simulation model. The results indicated that: (1) The runoff changed in the same trend either with rise and fall in mean value or variation coefficient of rainfall; (2) In the four given scenarios (mean value of rainfall has increased by 20% and 40%, decreased by 20% and 40%, respectively), change magnitude of runoff was similar under same change magnitude of mean value of rainfall; (3) The average annual runoff raised by 24.93% when the variation coefficient of rainfall raised by 40%, and raised by 10.84% when the variation coefficient of rainfall raised by 20%. However, it fell by 3.84% and 5.35% respectively when the variation coefficient of rainfall fell by 20% and 40%, which presented that the increase of variation coefficient of rainfall has a greater impact on runoff than the decrease of variation coefficient of rainfall does. The intensity of rainfall change is an important factor affecting the runoff, and heavy rainfall has a great effect on the runoff; (4) Change of runoff due to fluctuation of variation coefficient of rainfall gradually decreased, when variation coefficient of rainfall gradually declined; (5) Average annual runoff raised by 33.99% as mean value of rainfall raised by 20%, and raised by 10.84% as variation coefficient of rainfall raised by 20%, which means change of mean value of rainfall has bigger impact on runoff change than variation coefficient of rainfall; (6) Variation of monthly runoff caused by different rainfall scenarios is more obvious in June, July and August than other months.

Key words: runoff, rainfall, HSPF, stochastic simulation, Dongjiang River Basin

CLC Number: 

  • P339