| Understanding the potential of production is critical for improving crop yield and helping farmers to adopt effective cultivation strategic.Fertilizer utilization efficiency is an important parameter of recommended fertilization,and it is also an significant index for sustainable development of agriculture.Due to the existing soil test methods had limited applicability and the blurring of the mechanism of variability in phosphorus use efficiency on different regions,the further exploration of nutrient precision management is restricted.Basing on rice production situation and experimental dataset in Liaoning Province from 2006 to 2010.We analysis rice yield potential and yield gap in Liaoning Province.At the same time,the soil phosphorus supply?Ps?is determined by mapping method of fertilizer effect function and discussing the variation mechanism of phosphorus use efficiency?REP?basis of it.Provide the foundation for improving rice yield and nutrient use efficiency.The main conclusions of this research are as follows:1.Rice yield of Liaoning province has great potential and there are significant variations in different regions.The modeled yield,Highest recorded yield,experimental yield and farmer's average yield of Liaoning were 15916 kg·ha-1,11152 kg.ha-1,8659 kg·ha-1,7469kg·ha-1 respectively.Eliminated the yield gap between Highest recorded yield and farmers' average yield?YGR?,rice yield can increased 49.3%,and eliminated the yield gap between experimental yield and farmers,average yield?YGE?,rice yield can increased 15.9%.Southern Liaoning short-term yield gap was the lowest,and northeastern of Liaoning province is the highest.For the long-term yield potential,western Liaoning was the highest,but restricted by planting area,the contribution of increasing of rice production is very small.2.The average of Ps and UP0 of rice fields in Liaoning province are 248.73kg·ha-1,90.75kg·ha-1 respectively,the average of difference between Ps and UP0 range from 6.74 kg·ha-1 to 437.76kg·ha-1.Comparing UP0 and Ps with RY,we affirmed that it is better for using Ps to stand the representative of soil phosphorus supply.3.The crop phosphorus demand?UP0/Ps?and the availability of phosphorus fertilizer?Pmax/Ps?are used to synthesize three major influencing factors as soil?Ps?,crop?UP0?and fertilizer?Pmax?and comprehensive crop Demand and nutrient supply in two aspects to give a reasonable explanation for the variability of the REP.In the context of different environments and management,the three factors will constitute different combinations of UP0/Ps and Pmax/Ps.Through the establishment of the two indicators and REP model,the relationship of phosphorus use efficiency between each field can be contacted.The results show that the variation of phosphorus use efficiency in Liaoning Province was mainly affect by Pmax/Ps.Increasing the effectiveness of phosphate fertilizer in soil is the most important problem to improve phosphorus use efficiency in Liaoning Province.Meanwhile,the relationship between supply and demand must be coordinate.4.Phosphorus use efficiency is 11.03%,the total residual phosphorus content varied from 66.18 kg · ha-1 to 616.11kg · ha-1,and large variation in different areas.The average of soil residue was 157.98 kg · ha-1 and the average residual fertilizer was 114.98 kg · ha-1,accounting for 57.88%and 42.12%of the total residual,respectively.5.Based on rice yield and phosphorus use efficiency in Liaoning Province,we divide the existing fields into four types,through the analyze of nutrient supply and crop uptake,we can know that under the same soil phosphorus supply condition,demand for nutrients should be improved to achieve the purpose of increasing yield.Increasing low efficiency of plots need to coordinate the demands for nutrient and the availability of fertilizers.The main influencing factors of phosphorus use efficiency on every types are Pmax/Ps,which was consistent with the overall situation in the province. |
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