Optimization of maize tillage methods in the west of Jilin Province in the viewpoint of virtual water
虚拟水视角下吉林省西部玉米耕作方式优化

Virtual water is an important research field of food security and water security,and the current research is mainly concentrated on the calculating methods of virtual water content,national or regional virtual water flow and the practicing significance of virtual water strategy,in other words,they mainly focus on macro and middle scales,seldom on micro level.In order to discuss the micro study of virtual water,we developed the field experiments of maize virtual water under different tillage methods in the west of Jilin Province during 2005-2007.There are 6 tillage methods which are 65-cm ridge stage,65-cm ridge furrow,43-cm ridge stage,43-cm ridge furrow,98-cm double-row ridge stage and 130-cm triple-row ridge stage.The optimal tillage method for maize can be confirmed by comparing the maize virtual water content per unit weight and its stability under the 6 kinds of tillage methods.Thereby,high efficient utilization of water resources can be realized and a new idea can be provided for solving the problem of water shortage.Through three years of field experiments,98-cm double-row ridge stage is considered to be the best tillage method,in which the maize virtual water content per unit weight was lower with small fluctuation,especially the least virtual water in extreme drought year.Therefore,it is suggested that maize tillage method should be changed from 65-cm ridge stage to 98-cm double-row ridge stage in the study region.