武威绿洲农业水足迹变化及其驱动机制研究

农业活动通过改变绿洲赖以生存的水生态系统而影响着绿洲的稳定性。1950-2007年武威绿洲农业水足迹上涨了近7倍,而农业水足迹效率仅提高1.75倍;粮食作物水足迹比例过大,57 a间平均达74.32%,其中,2002年以前粮食作物水足迹比例呈下降趋势,但在2002年达到最低点58.63%之后开始出现反弹。人口增长和人民生活需求所驱动的以粮食生产为主体的农业规模扩大和农业开发强度加大,是农业水足迹增长的主要原因。适当压缩农业规模,加快农业内部结构调整,加大政府对农业节水灌溉工程的投入和农业节水技术的推广,是控制武威绿洲农业水足迹增长过快,维护绿洲生态系统稳定的有效方式。

Dynamic Analysis on Agricultural Water Footprint and Its Driving Mechanism in Wuwei Oasis

Agricultural activities influence the stability of oasis by changing its aquatic ecosystem that oasis depends on. The agricultural water footprint of Wuwei Oasis in 2007 is about 8 times of that in 1950, while the efficiency of agricultural water footprint grows slowly only by 1.75 times. There is significant negative correlation between the efficiency and the proportion of the food crops water footprint. The proportion of the food crops water footprint in Wuwei Oasis presents a declining trend before 2002 and upgrades after 2002. The lowest proportion is 58.63% in 2002. The rapid population growth and livelihood demand are the main driving factors for the increase of the land development intensity and the agricultural water footprint. Therefore, appropriate decrease of agricultural scale, agricultural structural adjustment, increasing the government’s inputs to agricultural water-saving irrigation, extending agricultural water-saving technology as well as improving water management systems are all effective measures to control the excessive growth of water footprints, to achieve efficient utilization of agricultural water resources and further to maintain the stability of oasis ecosystem in Wuwei.