An Analysis Of The Relationship Between Phosphorus Use Efficiency And Soil Olsen-P In The Wheat,Rice,Corn Land

Phosphorus is one of the three major nutrient elements necessary for crop growth and development.It is mainly derived from phosphorus fertilizers and soil Olsen-P contents.A reasonable amount of phosphate fertilizer can improve the yield and quality of the crop.Due to the complexity distribution of soil Olsen-P contents,and the different crop varieties have different absorption characteristics,all of these have increased the difficulty of determining the reasonable application amount of phosphorus fertilizer.However,as the result of the unreasonable application amount of phosphorus fertilizer,the domestic phosphorus use efficiency（PUE）is lower than the international level,the waste of limited phosphorus resources and the eutrophication of water bodies have been regarded as an urgent problem in Chinese agricultural industry.Therefore,it has great theoretical and practical significance to explore the quantitative relationship between the phosphorus use efficiency and the crop land soil Olsen-P contents.It can save limited phosphorus resources,achieve weight loss and increase efficiency,improve the phosphorus use efficiency and protect the ecological environment.This study is based on field trial data of wheat,rice and corn in china.By searching Chinese literature,Wan fang database,Web of science and other literature databases,and research time and keywords are set,then the database including 1253 data sets was established.According to the database,the distribution of the Chinese crop land soil Olsen-P contents and phosphorus use efficiency was determined,the influencing factors of phosphorus use efficiency were analyzed,the range of soil Olsen-P contents and phosphorus application amount was divided,explored the appropriate amount of phosphorus applied to soil with different available phosphorus content under the conditions of ensuring high yield and stable yield,the phosphorus use efficiency data under suitable phosphorus fertilizer application amount was screened,and the quantitative relationship between phosphorus use efficiency and soil Olsen-P contents under the condition was discussed.The specific research results are as follows:1)At present,the application amount of phosphorus fertilizer are concentrated in 50–150 kg/hm².The phosphorus use efficiency varies greatly among different soil types.And the phosphorus use efficiency is less than 25%,the soil Olsen-P contents is generally low.From the national perspective,and the phosphorus use efficiency and soil Olsen-P contents in the Yangtze River Delta and Huanghuaihai area are lower than those in Northeast China and Guangxi.2)In the soil of wheat planting soil pH>7.5,and the soil of corn and rice planting soil pH 6.5-7.5 is more effective than other pH conditions soil.The phosphorus use efficiency of wheat and corn decreased with the increase of soil organic matter content,and there was no significant difference in rice.Under the condition of low Soil available nutrient contents（N<60 mg/kg,P₂O₅<10 mg/kg,K₂O<60 mg/kg）,the phosphorus use efficiency of maize was the strongest.Under the condition of low soil N and low P₂O₅,the phosphorus use efficiency of wheat was the strongest,and there was no significant difference in rice.3)On the basis of ensuring high yield and stable yield,the principle of reducing the amount of phosphorus fertilizer applied to soil with high Olsen-P contents and increasing the amount of phosphorus fertilizer applied to soil with low Olsen-P contents,the minimum phosphate fertilizer application amount was selected as the recommended suitable phosphate fertilizer for this study.In the range of soil Olsen-P contents<5,5–10,10–15,15–20,20–25 and>25 mg/kg,the appropriate phosphorus application amount for wheat are>150,90–120,30–60,30–60,30–60 and 30–60kg/hm²respectively,the appropriate phosphorus application amount for rice are>150,>150,>150,>150 and 30–60,<30 kg/hm² respectively,the appropriate phosphorus application amount for maize are 120–150,120–150,30–60,30–60,30–60 and<30 kg/hm² respectively.4)On the condition of suitable phosphorus fertilizer amount,the quantitative relationship between phosphorus use efficiency and soil Olsen-P contents of wheat is y=-0.042 x²+1.7509 x–1.0943（n=94）,that of rice is y=0.0507 x²–0.7218 x+6.8698（n=36）,that of corn is y=-0.0355 x²+1.35818 x–0.1778（n=47）.Under these conditions,the thresholds of phosphorus use efficiency of wheat and corn increase with the increasing of soil Olsen-P contents are 20.9 mg/kg and 19 mg/kg respectively.