采用线性矩法及珠江三角洲19个水位站近50 a的年最高实测洪水位,在水文站点一致性分析及水文相似区鉴别的基础上,进行区域洪水频率计算及空间特征分析.结果表明:整个珠江三角洲可划分为3个水文相似区,其形成动力机制各不相同;3个水文相似区和非相似区的最佳分布函数各自不同;整个区域的洪水频率分布自上游(内河地区)到下游(沿海地区)逐渐减小,证明外海地区比上中游等其他地区面临更大的洪涝灾害威胁.
Using the L-moments approach and the observed highest water levels in the Pearl River Delta (PRD) region at 19 hydrological stations over nearly 50 years, regional flood frequency analysis and spatial patterns were conducted and identified based on discordance test of hydrological stations and identification of hydrological homogeneity. The results indicate that the whole PRD region can be divided into three homogeneous regions with different formation mechanisms. The optimal distribution functions for the three homogeneous regions and the non-homogenous regions are found to be not identical. The flood frequency of the whole PRD region gradually decreases from upstream (inland river regions) to downstream (coastal regions). This suggests that the coastal regions have a greater chance of flood disasters than the upper and middle reaches.