Effect of fertilizing structure on the change of organic matter and N,P and K nutrients in sand soil

Through long-term fertilizing experiment in sand soil,the effects of different fertilizing structures on crop yield and the changes of organic matter and N,P and K nutrients in sand soil were analyzed. The results showed that wheat yield decreased to 21.1%～34.3% and maize yield increased to 155.9%～209.7% by solely applying of nitrogen fertilizer,wheat yield increased to 29.3%～39.7% and maize yield decreased to 50.4%～63.0% by solely applying phosphorus fertilizer,but they were increased by 3.43～5.79 times and 3.04～4.23 times respectively by coordinate application of N with P fertilizer.Manure significantly raised crop yield and nutrient content of soil,but no matter nitrogen and phosphate fertilizer were solely or coordinately applied,organic matter only kept at low level,furthermore,soil potassium was heavily consumed.Nitrogen was easy to move down to lower soil layer when nitrogen fertilizer was solely applied,whereas it was favorable to nitrogen to be maintained at upper soil bed as nitrogen fertilizer was coordinately fertilized with phosphate fertilizer.The coordinate application of manure with nitrogen fertilizer or with nitrogen and phosphate fertilizer was optimum fertilizing structure.