1956-2009年皇甫川流域不同历时最大暴雨量周期性和趋势性分析

以皇甫川流域为研究对象，采用年最大构建法以“小时”为单位进行滑动选样摘取不同历时年最大暴雨量，以GIS为平台，利用泰森多边形统计流域不同历时最大暴雨量，采用自相关系数和方差谱密度来表达水文序列内部线性相依性质和水文系列的振动现象，进而分析水文系列的周期性，采用周期模型进行趋势性预测。研究结果表明:不同时段最大暴雨量随年代变化的趋势基本一致，均表现为20世纪70年代前暴雨量最大，80年代最小，90年代居中，近10 a仅次于20世纪70年代之前；与20世纪70年代之前相比，80年代以来随着降雨历时的延长最大降雨量减少的幅度达到5.1%～19.1%，皇甫站最大24 h降雨量存在3 a、7 a和15 a的变化周期，未来仍会出现大暴雨的可能性。

The Maximum Rainfall Amount Cyclical and Trend Analysis of Different Durations in Huangfuchuan Basin During 1956-2009

Huangfuchuan basin was taken as study area, the annual maximum building method was used to calculate the largest rainstorm of different durations in hour by the sliding sample way. Based on GIS platform, Thiessen polygon was used to calculate Watershed lasted biggest rainstorm, autocorrelation coefficients and variance spectral density were used to express sequence internal linear dependence hydrological and hydrogeological nature series vibration phenomena, and then the cyclical hydrological series were analyzed by using the cycle model for trend prediction. The results showed that the maximum rainfalls of different storm occurrence periods have the same changing trend over time, and there were largest amounts of rainstorm before the 1970s, and the smallest in 1980s, the middle in 1990s, and the amount of heavy rains the past 10 years was little smaller than the 1970s. Compared with the 1970s, the percentage of reducition since the 1980s with the extension of rainfall, the rates of decrease was 5.1% to 19.1%, the maximum 24-hour rainfall of Huangfu station existed a change cycle of 3 years, 7 years and 15 years, respectively. Huangfuchuan watershed still has the possibility of heavy rain.