横山岭地区多年降水量趋势及频率分析

Analysis of Trend of Annual Precipitation and Frequency in Hengshanling Area

为研究小流域内降水趋势的特点。以横山岭地区为例,选用能充分反映该地区降水量变化规律的代表站的近50年的实测资料进行分析。采用线性倾向率法和Mann-Kendall检验法,分析出降水量总体趋势趋于减少但趋势不明显,且近些年来有上升趋势。其突变年份为1964年和2009年。根据数理统计距法得出部分参数多年平均降水659.2 mm、Cs=0.79、Cv=0.27,再以P-Ⅲ曲线法配线,分析本地区的降雨的频率。根据各个地区的特征趋势以及频率统计参数结合自然气象等诸多因素的影响推断该地区降水年际变化较大,易发生洪、旱灾害。需要加强对降雨趋势和频率以及形成径流过程的进一步研究。

For surveying the characteristics of the precipitation trend in the small watershed,Taking Hengshanling area as an example,the article is based on nearly 50 years data collected from the representative station which can fully reflect the change of precipitation in this area. The linear trend rate test and Mann- Kendall test methods are used to analyze that the overall trend of precipitation tends to decrease but the trend is not obvious,and in recent years there is an upward trend. The mutation for the years are 1964 and 2009. According to the statistics from the conclusion of part parameter precipitation 659.2 mm,Cs= 0. 79,Cv= 0. 27,followed by P- Ⅲ curve distribution,local rainfall frequency is be analyzed. According to the characteristics of each region and the trend of frequency statistical parameters in combination with natural weather and many other factors that the interannual variation of rainfall in the area is large,prone to flooding,drought disaster. The rainfall trend and frequency should be further studied together with the formation of runoff process.