The changes of planting structure and rational use of water resource in the oasis of Minqin County，Gansu Province

The agricultural statistical information of Minqin County during 1949～2000 was analyzed．The results show that there are great changes on the planting structure and yield during this fifty-two years in the oasis of Minqin County．The total tendency of the planting area of cereal crops in proportion tO the total planting area is minishing．The wheat planting area has been reduced by 15％ from 1982 tO 1998，while those of maize，cotton and other economic crops have been increased．especially that of the seed melon has been increased by 10％ ．Finally，the relationship between the crop water requirement and the water resource-carrying capacity and their affections tO adjust agricultural production are analyzed ．