黑河流域金塔段水文特征与降水量关系初探

利用甘肃省酒泉市金塔县气象站1973~2014年降水量数据以及鸳鸯池水库径流量资料,通过最小二乘法、Mann-Kendall法、小波分析法等统计方法,对降水量与径流量的关系进行了不同角度的分析研究。结果表明,(1)42年里金塔县年降水量呈现出缓慢上升的变化趋势,降水量趋势倾向率为3.65 mm/10年。春季、夏季、秋季、冬季平均降水量趋势倾向率为-0.02、-0.47、0.51、0.62 mm/10年。四季当中夏季降水量占到全年的比例为62%,该季节降水量的减少必定会影响全年降水量变化。鸳鸯池水库1984~2004年径流量处在偏少时期,2004年之后径流量处在相对较多的时期。通过对径流量的季节分析来看,夏季平均径流量为1.01×108 m~3,为四季中最大,占到全年径流量的32%。年降水量与年径流量之间的相关系数为0.352,四季当中夏季降水量与径流量以及秋季降水量与径流量的相关性均通过了0.01的显著性检验。(2)Mann-Kendall法,对鸳鸯池水库年平均径流量序列做突变检测分析发现,2009年是径流量由减少转为增加趋势的突变点,对鸳鸯池水库径流量序列进行Morlet小波变换特征分析,在15年左右的尺度以及32年左右的时间尺度,径流量变化周期显著,小波方差进一步确认32年是径流量序列变化的第一主导周期,表现出的能量最大,而15年是第二主导周期。(3)对年降水量与径流量建立关系模型,选择三次方程(Cubic)作为建模需要,通过降水量来反映出径流量的变化特征。

The Relationship Between Hydrological Characteristics of Jinta Heihe River Basin and Precipitation

Using the Gansu Province Meteorological Bureau in Jinta county from 1973 to 2014, and the precipitation data and the runoff data of Yuanyang pool, by means of least square method, Mann-Kendall method, wavelet analysis and other statistical methods, the relationship between precipitation and runoff was analyzed and studied. The results showed: ①42 years in Jinta county annual precipitation trend was slowly rising, precipitation tendency rate was 3.65 mm/10 a. In spring, summer, autumn and winter, the average precipitation tendency rate was -0.02, -0.47, 0.51, 0.62 mm/10 a. The proportion of summer rainfall in the four seasons was 62%, which was bound to affect the annual precipitation change. 1984~2004 Yuanyang pool reservoir runoff was in less time, after 2004 the runoff was in a relatively large period. Through analyzing runoff season, the average runoff of summer was 1.01×108 m3,which was the the biggest of four seasons, accounted for 32%of the annual runoff. The correlation coefficient of annual precipitation and annual runoff was 0.352, the four seasons of summer precipitation and runoff and the correlation of autumn rainfall and runoff were passed the significance test of 0.01. ②Mann-Kendall method, analysising the mutation detection of the mandarin duck pond reservoir average annual runoff sequence, 2009 was the abrupt change point of the trend of the runoff from reduce to increase. The mandarin Yuanyang pond reservoir runoff series Morlet wavelet transform characteristic analysis, around 15 a dimension as well as the time scale of about 32 a, runoff change cycle significantly. Wavelet variance analysis further confirmed 32 a was the first dominant runoff series change cycle, it showed the biggest energy, and 15 a was the second leading cycles. ③The relationship model of annual precipitation and runoff was built, choosing three equations modeling (Cubic) as a need, to reflect the variation characteristics of surface runoff by precipitation.