为了明确石羊河流域灌溉水利用水平和存在问题,提高农业灌溉用水利用率,进一步发展节水灌溉,应用首尾测算法对石羊河流域不同尺度灌溉水利用率进行了估算及分析。结果表明:由于节水灌溉模式的推广应用和灌区节水改造措施的实施,1976-2005年间石羊河流域灌溉水利用率有较大的提高,由1976年的34%提高到2005年的54.6%;全流域20个主要灌区中,自流水灌区中古浪县古浪灌区的灌溉水利用率最高,2001~2005年平均为56.7%,地下水利用为主的井泉灌区中永昌县的四坝灌区灌溉水利用率最高,2001~2005年平均为64.O%;石羊河流域县区中古浪县灌溉水利用率最高,2001~2005年平均为55.0%。
In order to improve the irrigation water use efficiency of the Shiyang River Basin and meet the demand of the water saving irrigation development, irrigation water use efficiency of different scales in the Shiyang River Basin was evaluated by the head-end measurement method. The results indicated that with the execution of water-saving reconstruction,irrigation water use efficiency in the Shiyang River Basin increased greatly from 34% in 1976 to 54.6% in 2005. Irrigation water use efficiency in Gulang irrigation district was the highest among surface water irrigation districts,and the average value from 2001 to 2005 was 56.7%. Irrigation water use efficiency in Yongchang irrigation district was the highest among groundwater irrigation districts,and the average value from 2001 to 2005 reached 64.0%. Irrigation water use efficiency in Gulang county was the highest in all the counties of the Shiyang River Dasin, and the average value from 2001 to 2005 reached 55.0%.