Based on the variable analysis of Chinese north and south grain transfer and combined agricultural water footprint theory,this paper puts forward that at the same time of implementing South-to-North water diversion entity engineering construction,the"agricultural North-to-South water diversion virtual engineering"has been formed and carried out since 1990.The calculating results showed that:this engineering has transferred over 20 billion cubic meters virtual water from 1990 to 2008,which was much more than...
修改评论