基流是河川径流中相对稳定的径流组成部分, 基流分割在水资源、水环境和水安全的管理研究中都有着重要 的应用。为了探究沿长江干流的基流变化特征, 使用递归数字滤波法对长江干流7 个水文站进行基流分割研究。 结果表明, 各站基流指数在01 768~ 01 798 之间。对朱沱站- 大通站区间基流量贡献最大的区间是宜昌站- 螺山 站, 其次是朱沱站- 寸滩站, 最小的是万县站- 宜昌站。2000 年前后, 长江干流基流量出现明显的衰减变化。基流 量衰减最大的是宜昌站( 衰减率为81 82%) , 其次为万县站( 衰减率为81 79%) 。

Abstract:Baseflow is a relatively stable compo nent o f str eamflow, and baseflow separ ation is widely used in the management and research of w ater r eso ur ces, water env ir onment, and water secur ity . In or der to inv estigate the var iatio n of baseflow along the Yangtze Riv er, recursive digital filters method was emplo yed to calculat e the baseflow at seven hydr olo gica l stat ions in the main2 str eam of the Yangt ze River. The research results showed that the BFI ( baseflow index ) is betw een 01 768 and 01 798 at each stat ion. T he r iver reach between Yichang and Luo shan stat ions has the g reatest co nt ribution to the basef low betw een Zhutuo and Datong statio ns, follow ed by the river reach betw een Zhutuo and Cunt an stations, and the smallest is the r iver r each betw een Yichang and Wanxian statio ns. Around the year o f 2000, the basef low in the mainstream of the Yang tze River decreased sig nifi2 cantly . Basef low at Yichang st ation had the hig hest r eduction rate o f 81 82%, follow ed by Wanx ian station w ith a r eductio n rat e of 81 79%。

国家自然科学基金项目( 41201029 ) ; 高等学校博士学科点专项科研基金( 20120094120019) ; 中国博士后科学基金 ( 2013M540410) ; 河海大学国家级大学生创新训练项目( 201410294004)