Flood changes during the past 50 years in Wujiang River, South China (pages 3561–3569)

摘要

Changing trends of peak flood and flood duration in the Wujiang River Basin are detected with the help of the Mann–Kendall testand the Pettitt analysis during the past 50 years. Results indicate that the peak flood and the flood duration at Lishi Station havedifferent changing features. The peak flood showed only marginally increasing trend, whereas the flood duration exhibiteddecreasing trend at the significance level of 90%. The result shows a weak positive correlation between the peak flood and theflood duration. The changes of flood duration are influenced by the total rainfall duration, which is in downward trend atsignificance level 90%. In addition, the changing trends of peak flood are similar to the total rainfall amount. In the change-pointanalysis, it was found that the change points for the peak flood and flood duration series were in the years 1993 and 1966,respectively. Human activities such as the construction of reservoirs were the main driving forces causing the change of floodduration. The periodicity of the peak flood during the period 1955–2007 at Lishi Station is detected by using the waveletanalysis. The result indicates that the peak flood at Lishi Station displayed alternation between big floods and small floods on the25- to 26-year period. At the same timescale, the peak flood of Wujiang River showed an evidence of change between big floodsand small floods. It was essential to be prepared and aware of the consequences of climate changes and human influencesaffecting the water resources in the Wujiang River Basin. This result is expected to draw more attention from the localgovernments in its decision making and water resource management. Copyright © 2012 John Wiley & Sons, Ltd.