汉江上游近50年降水序列变化及其干旱预测研究

本文通过对汉江上游9个主要水文站49年(1961-2009)的月降水资料进行分析,应用非参数检验方法(Mann-kendall法)并结合一元线性回归方程对其进行了降水趋势检验,结果表明:汉江上游49年来降水呈明显减少趋势,干旱发生频率有加大趋势,应引起高度重视。选择40年(1961-2000)的降水数据分别对这9个水文站建立灾变预测模型GM(1,1),对该地区未来一定时期内干旱发生的时间进行预测。通过残差检验,后验差检验,预测模型精度较高,检验结果基本与实际相符。因此,本文对研究区抗旱减灾及其农业生产具有一定的科学指导作用。

Study on Precipitation Change and Drought Prediction in Upper Reaches of Hanjiang River During the Last 50 Years

Monthly precipitation were analyzed based on data from 9 representative hydrologic stations in the upper reaches of the Hanjiang River during 1961-2009 by using nonparametric test method(Mann-kendall method) and linear regression equation.The results show that precipitation reduced obviously during the last 49 years in the upper reaches of the Hanjiang River and drought frequencies show increase trend.Enough attention should be paid for it.The monthly rainfall data in this region from 1961 to 2000 were applied to set up the GM(1.1) model for the 9 hydrologic station.The drought time of the region in the future was forecasted.Through the residual test and Posterior poor inspection,the models’ definition is so accurate that the essential result approaches the factual data.Therefore,these results are of great scientific guiding in drought resisting,disaster alleviation and agricultural production over the upper reaches of the Hanjiang River.