PROGRESS IN GEOGRAPHY ›› 2012, Vol. 31 ›› Issue (9): 1149-1156.doi: 10.11820/dlkxjz.2012.09.005

• Original Articles • Previous Articles     Next Articles

Variability of Precipitation in the Yongjiang River Basin during 1956-2010

CHEN Ruizhi1,2, SANG Yanfang1, WANG Zhonggen1, LI Zongli3   

  1. 1. Key Laboratory ofWater Cycle and Related Land Surface Processes, Institute of Geographic Sciences and Natural Resources Research, CAS, Beijing 100101, China;
    2. Graduate University of Chinese Academy of Sciences, Beijing 100049, China;
    3. General Institute of Water Resources and Hydropower Planning and Design, Ministry ofWater Resources, Beijing 100120, China
  • Received:2012-03-01 Revised:2012-06-01 Online:2012-09-25 Published:2012-09-25

Abstract: Global climate change enhances the uneven distribution of water resources in many basins and regions, and it further causes the hydrological extreme events (e.g., floods, drought) occurring concurrently, and more unexpectedly and frequently. In this paper, the Yongjiang River Basin is chosen as the study area, and the daily precipitation data measured during the period 1956-2010 were analyzed by the precipitation concentration degree and the Mann-Kendall (MK) test methods, aiming to investigate the precipitation variability in this region. The results show the obvious inter-annual variations of precipitation were observed in the Yongjiang River Basin. After the 1980s, a significant downward trend of the PCD value of precipitation was detected by the MK test, which was mainly attributed to the decreasing proportion of the flood season precipitation in the annual precipitation, especially in May; while the proportion of precipitation in the nonflood season increases, especially in January. The storms with a rainfall of 50-100 mm/day shows an upward trend. In summary, an attenuation action of flood is detected in the Yongjiang River Basin, which is favorable for the water resources development and use in this region.

Key words: Mann-Kendall test, PCD, precipitation, Yongjiang River Basin