In order to further reveal the characteristics of the storm-floods in the area,we took the observed data of the annual maximum flood and its corresponding storm,as well as typhoon information,during 1956-2011 in Xixi watershed of Fujian Province and divided storm-floods into two types,those that occurred during typhoon and non-typhoon seasons.Then,the characteristics of spatial and temporal variations of storm-flood were analyzed respectively with indices describing the spatial and temporal heterogeneity in the southeast coastal areas.A multiple linear regression analysis was used to estimate the relationship between these storm indices and flood peak discharges.The results indicated that 81％ of non-typhoon storm-floods occurred between April and June,and 70％ of typhoon storm-floods occurred between July and September.The number of typhoon storm-floods was twice more than that of non-typhoon storm-floods.Different types of rainstorm occurred in different seasons,leading to varied responses of flood.There were obvious differences in the characteristics of spatial and temporal variations of typhoon and non-typhoon storm-floods.It also indicated the great significance of distinguishing typhoon and non-typhoon storm-floods in order to further reveal the spatial and temporal variations of storm-floods in the southeast coastal areas.%为了进一步揭示我国南方地区暴雨洪水的时空变化特征,以东南沿海晋江西溪流域为例,基于1956-2011年历年最大一次洪水及其相应暴雨实测资料,以及东南沿海台风资料,将暴雨洪水区分为台风和非台风暴雨洪水两类,分别统计分析反映暴雨时空变化特征的一系列指标;应用多元线性回归模型,建立洪水洪峰流量与暴雨特征要素的多元相关关系.结果表明,西溪流域的非台风暴雨洪水主要发生在前汛期,其中81％分布在4-6月;台风暴雨洪水主要发生在后汛期,70％集中发生在7-9月份,其数量为非台风暴雨的两倍之多.暴雨类型的不同,其前期降水、次降雨量、降雨强度、暴雨中心位置、暴雨的空间分布和时程分配特点也相应变化,非台风暴雨通常降雨强度小,历时长,降雨时间上分布不均,暴雨前期流域下垫面含水量大;而台风暴雨降雨量较大,降雨强度明显较高,具有明显的降雨中心,空间分布较不均匀导致台风和非台风暴雨洪水时空变化特征差异明显.
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