QIU Hai-jun1, CAO Ming-ming1, WANG Yan-ming2,HAO jun-qing 3, LIU Wen1 ,HU Sheng1
(1.College of Urban and Environment Science , Northwest University , Xi’an 710127 , China;
2. School of Chemistry and Environmental Science, Shaanxi University of Technology, Hanzhong 723001,China;
3.School of Business, Xi’an Financial and Economic University, Xi’an 710061,China)
Abstract: This paper analyzed the change of flood damage by using wavelet analysis and Hurst index from 1950 to 2010, revealing susceptibility, multiple time scales, cycle characteristics and mutation of time sequence of flood damage. The results showed that: 1) according to the results, the Hurst index of the affected area is 0.9338, with a very positive sustainability and an increasing trend. Hurst index of population death is 0.4845, with a weak reverse sustainability and a weak increasing trend. Hurst index of the collapsed house is 0.6124, with a weak positive sustainability and a weak declining trend; 2) the wavelet analysis method has better multi-scale features that can describe the flood disasters in change, and identify mutations in the disaster sequence point position, not only to extract the different disaster sequence variations, also also to predict disaster indicators of change in the short term, and provide a new tool to complexity theory; 3) large-scale nesting cycle of the small-scale cycle. Overall small-scale performs shock severely, there is no obvious rule to large-scale significance or to enhance or increase first and then decrease; 4) the flood affected areas in China generally maintain an increasing trend. There exist the main 1 and 2 periods at the 9th and 25th years .The population death in general maintains a marked decline. There exist the main 1 and 2 periods at the 8th and 18th years. The collapsed houses on the whole maintain a decreasing trend. There exist the main 1, 2 and 3 periods at the 8the and 17th and 25th years, respectively..
Key words: flood damage; multiple time scale; wavelet analysis; Hurst index
EARTH AND ENVIRONMENT Vol. 42, No.1, Tot No.297, 2014, Page 17-24
