黄河源区水文气象要素时空变化特征分析

Study on Spatio-temporal Variation Characteristics of Hydro-meteorological Factors in the Source Region of Yellow River

为充分了解黄河源区旱涝变化特征,基于黄河源区1961—2016年水文气象资料,采用Mann-Kendall法、Pettitt检验及Morlet小波分析法系统分析年降水量、年平均气温和年径流量序列的趋势、突变和周期性,并采用克里金插值和空间变差系数研究年降水量和年平均气温的空间变化特征。结果表明,年降水量上升趋势不明显,没有明显的突变性,在30 a左右周期显著;年平均气温上升趋势显著,在1997年前后存在较强的突变性,无明显周期;年径流量下降趋势明显,在1989年前后存在较强的突变性,在30 a左右周期显著;年降水和年平均气温的空间差异明显,年降水量的空间分布差异性在减小,年平均气温的空间分布的变化趋势不明显。2000年前,年平均气温空间分布差异比较大,2000年后空间分布比较均匀。研究成果有利于认识流域水资源演变规律,为水资源管理提供技术支撑。

In order to understand the variation characteristics of drought and flood in the source region of Yellow River sufficiently,based on the hydro-meteorological data of the source region of Yellow River from 1961 to 2016,this paper analyzes the trend,mutation and periodicity of annual precipitation,annual average temperature and annual runoff by the the Mann-Kendall method,Pettitt test and Morlet wavelet analysis method,and studies the spatial variation characteristics of annual precipitation and annual average temperature through the Kriging interpolation and spatial variation coefficient.The results show that;for the annual precipitation,its rising trend is insignificant,without significant mutation and with significant periodicity of 30 years;for the annual average temperature,its increasing trend is significant,with strong mutations around 1997 and without significant periodicity;for the annual runoff,its decreasing trend is significant,with strong mutations around 1989 and significant periodicity of 30 years;the spatial distribution difference of annual precipitation and average temperature are significant,with decreasing trend for spatial distribution difference of annual precipitation and with obvious variation trend for that of annual average temperature;before 2000,the spatial distribution difference of annual average temperature was obvious,but that was even after 2000.The research is helpful for understanding the evolution characteristics of water resources in river basin,which can serve as a technical reference for the water resource management.