Effects of Different Fertilizer Treatments on Soil Fertility and Wheat Yield in Loess Plateau East of Gansu

The effects of the different organic manure with equivalent nitrogen and phosphorus on the yield of winter wheat,water use efficiency(WUE) and soil fertility were investigated from 2005 to 2011 in Loess Plateau East of Gansu.The results showed that the combined fertilizing of NP chemical fertilizer with organic matter was more advantaged for improving soil ferity,the yield of winter wheat and WUE than the fertilizing of NP chemical fertilizer(CK2)and no fertilizing(CK1).The effect of chemical fertilizer combined with biological manure was significantly higher than others.Soil organic matter,total N,total P and total K were increased by15.5%,21.4%,14.1% and 5.9% comparing with that in 2006,respectively,and available P and K were heightened with 14.2 mg·kg-1 and 48.0 mg·kg-1,respectively.The yield of winter wheat(3 536.3 kg·hm-2) was the highest and increased by 53.2% and 86.7% comparing with CK2 and CK1,respectively.WUE(11.7 kg·mm-1·hm-2) was the highest and increased 30.2% and 71.2% comparing with CK2 and CK1 respectively.Therefore,chemical fertilizer combined with biological manure was significantly improving the soil quality under the rain and heat condition in loess plateau dry land east of Gansu,and soil fertility and yield of winter wheat were greatly accordant,which could be taken as the standard for soil fertility and yield level.