【摘要】 以西安地区年降水序列为参照,利用小波分析方法对灞河出山径流序列的周期性变化进行分析。结果表明,西安地区平均年降水序列和灞河出山径流序列存在着多时间尺度周期,并且基本具有同步变化的规律性,反映了人类活动对灞河出山径流序列的周期性影响不大。其中,变化较明显的周期是10 a1、5 a左右时间尺度,水文序列变化的高能量主要集中在较小的时间尺度上。用秩次相关分析法检验得出灞河出山径流序列均存趋势性,用有序聚类分析法分析得出灞河出山径流序列的突变年份是1948年。更多还原

【Abstract】 Taking precipitation sequence in Xi’an as reference,the periodic variation of runoff from mountainous watershed of Bahe River was analyzed.Results show that both of the reference data and examination data has periodicity of multi-scale of time,and the change rules are almost synchronous,which means that the human activity has little impact on the periodicity of the runoff sequence.The obvious periodic variation appears in the time scale of 10-year,15-year or so.The high energy of the variation of hydrologic sequence mostly appears at small time scale.Rank correlation analyses show that all of the runoff sequence change with tendency,and the sudden change appeared in 1948,as concluded by order cluster analysis method.更多还原