Systemic study on nutrients in irrigation desert soils of Gansu Province

In this paper，with the pot experiment and field experiment，the status of nutrients of irrigation desert soils at Minqin County in Gansu Province is studied The results show that the limiting factors nutrients of irrigation desert soils are the deficiency of N，P，Cu，Fe，and Zn．The relative yields of,sorghum from the soils non-applied with N ，P，Cu，Fe and Zn are 47．38％ ，68．77％ ，70．91％ ，78．40％ ，and 80．21％ respectively． In field experiment，the limiting factors nutrients are N and P fertilizers．Based on the treatment of OPT ，the application of N and P fertilizers can enhance the yield of corn prominently and the increasing amplitudes are l1．95％ and 22.60％ respectively．while reducing the N application decreases the yield prominently and the decreasing amplitude is 10．40％ ．