Effect of long-term fertilization on wheat yield and nutrient balance in dryland of the Loess Plateau

Based on a long-term experiment,the effects of long-term fertilization on wheat yield and nutrient balance were investigated.The results show that rational use of fertilizer can increase wheat yield significantly,and increase the amount of nutrient absorption and improve nutrient content of soil.The combination of N and P application can increase wheat yield by 111.7%.Compared with the single application of N fertilizer and single application of P fertilizer,adding manure can increase the yield by 32.7% and 155.7%.The combination of N,P and manure application can increase the amount of N,P and K absorption by 303.5%,128.6% and 238.8% separately.In single application of fertilizer,a part of soil nutrients will be deficit.In single application of N fertilizer,soil P loss is high as 100%,while in single application of P fertilizer,N loss is as high as 100%.In combination of fertilizer,there are different levels surplus of N and P.In the experimental region,the agricultural production should focus on the application of manure fertilizer and the combination of fertilizer reasonably.