Effects of phosphorus on crop water and nitrogen use efficiency under different precipitaion year in dryland

摘要

Absence of soil phosphorus constrained the crop yield, the use of limited water resource and nitrogen nutrient in dryland on the loess plateau. Reasonable phosphorus fertilization was also crucial to increase crop yield and improve water and nitrogen use efficiency. It was conducted that the effect of phosphorus application rate on crop yield, water consumption, nitrogen absorption, water use efficiency, and nitrogen use efficiency at long term fertilization experiment station in dryland on the loess plateau during different precipitation year. The results showed that during different type of year most of the indexes had similar trend of rising with phosphorus rate increasing in a lower range and dropping down in a higher range except for water consumption and harvesting index (HI). More higher phosphorus rates were unfavorable to crop yield, water and nitrogen use efficiency in both types of years but phosphorus application in all rates decreased HI and water consumption more than non phosphorus application treatment in dry year. So moderate phosphorus application was the favorable selection for higher crop productivity, water and nitrogen use efficiency in dryland on loess plateau, simutaneously may be helpful for improving utilization effect of phosphorus fertilizer.