白龙江干流代表站径流变化特征及未来趋势预测

白龙江引水工程被列入国家确定的172项重大水利工程项目之一,分析研究白龙江干流代表站径流变化特征并进行未来趋势预测,为实施白龙江引水工程提供技术支撑。对白龙江干流白云、舟曲、武都、碧口4个代表站1956~2013年的实测径流系列资料进行分析,采用周期波均值外延叠加模型、谐波分析模型和逐步回归分析模型组合形成的加法模型对代表站未来径流变化趋势进行分析预测。结果表明:(1)该4站9月份多年平均流量占全年径流量比例最大,主汛期6~9月多年平均流量占全年径流量比例达到50%左右。(2)4个水文站多年径流量变化趋势呈现出逐渐缓慢减少的趋势,上游减少的幅度比下游小。(3)预测2015、2020、2025年年径流量的结果是:白云水文站均小于多年平均值,武都水文站均大于多年均值,舟曲和碧口水文站在多年均值上下浮动。

Runoff Variation Characteristics of Representative Stations on Mainstream of Bailongjiang River and Trend Prediction

The Bailongjiang water diversion has been determined as one of the 172 large-scale water projects by the government, which can be offered a technological support by analyzing the runoff variation characteristics of the representative stations on the mainstream of the Bailongjiang River and predicting the change trend. Based on the observed runoff data from the 4 representative stations (Baiyun, Zhouqu, Wudu and Bikou) on the mainstream of the Bailongjiang River from 1956 to 2013, we made an analysis and forecast of the change tendency of the runoff by using an additive model combined with 3 models (the model of periodic wave mean epitaxial superposition, the model of harmonic analysis and the model of stepwise regression analysis). The results show that (1) the long-term average flow in September usually takes the highest percentage of the total in the whole year at the 4 stations, the long-term average flow from June to September often reach 50% of the total in the whole year; (2) there is a decreasing trend of the mean annual discharge at the 4 stations, of which reduction is less at the upstream stations (Baiyun, Zhouqu) than that at the downstream stations (Wudu, Bikou); (3) the prediction results of the annual runoff in 2015, 2020 and 2025 is that the runoff will be less than the long-term average runoff at the Baiyun station, more than the long-term average runoff at the Wudu station, and the annual runoff will float up or down the long-term average runoff at the stations of Zhouqu and Bikou.