中文摘要：

近几十年气候变化加剧了一些地区的水资源时空分布不均匀性，使水灾害事件呈突发、频发、并发、重发趋势。本文选取中国东南沿海的甬江流域为研究对象，基于近55年日过程降雨资料（1956-2010年），采用集中度分析和Mann-Kendall（MK）趋势检验等统计学方法，分析甬江流域降水的变化特性。结果显示，甬江流域20世纪80年代后，年降水集中度呈现显著（置信水平95％）的下降趋势，汛期降水量占年降水量比重减少，其中5月份降水量比重下降最为明显；而非汛期降水量占年降水量比重增加，1月份降水量比重增加最为明显；50-100mm／d级别的暴雨总量稳定且有增加趋势。总体上，甬江流域降水年内分布呈现坦化趋势，不同量级暴雨变化趋势有利于洪水资源化，因此结合合理的工程措施可以有效地增加该区域的水资源可利用量。

英文摘要：

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, aimin~ 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.