沂沭河流域夏季降水量与洪水发生规律之间的关系

基于沂沭河流域1950~2013年夏季降水量与最大洪峰流量的特征和规律,综合运用线性趋势分析、距平分析、相关分析和回归分析等方法分析了流域内夏季降水量与最大洪峰流量的周期性、时间序列趋势性及二者的关系。结果表明,60多年来沂沭河流域夏季降水量与最大洪峰流量之间存在着对应的丰枯周期,即1950~1974年为连续丰水年,1975~1989年为连续枯水年,1990年以后进入波动加剧的丰水周期;洪峰流量随夏季降水量的多少发生相对一致的变化趋势,二者均呈减少趋势,但夏季降水量减少趋势不明显;7月降水量和夏季降水量分别与最大洪峰流量之间存在正相关关系且关系密切,线性相关程度已达到显著水平;夏季降水量与最大洪峰流量之间的回归模型y=13.714x-1 549.2为有效模型。

Relationship of Flood Law and Summer Precipitation in Yishu River Basin

Based on the characteristics and regularities of the summer precipitation and largest peak discharge in Yishu River basin during 1950 to 2013, this paper had applied several comprehensive methods, such as trend analysis, anomaly analysis, correlation analysis and regression analysis, to investigate the time series tendencies, periodicity and the relationship between the summer precipitation and largest peak discharge in this basin. Some conclusions are drawn as follows. The summer precipitation and largest peak discharge in Yishu River basin has the corresponding dry-wet period: 1950-1974 is the continuous wet years, 1975-1989 is the continuous dry years, and since 1990 the Yishu River basin appears the volatile wet period. The summer precipitation and largest peak discharge in Yishu River basin has same tendency and they both appeared downward trend, but the summer precipitation decreased insignificantly; at the same time, the precipitation in July and the summer precipitation has positive correlation relationship with largest peak discharge. The positive correlation relationship is not only close but also significant and the regression model (y=13.714x-1 549.2) of the summer precipitation and largest peak discharge is effective.