Evaluation,Prediction And Control Of Accurate Management Of Maize And Rice Potash Fertilizer In Northeast China

Agriculture is the foundation of all people.Modern agriculture is a high-input and high-yield agriculture with chemical fertilizer as the main guarantee.It is particularly important to adopt comprehensive management measures to ensure the output without causing excessive pollution to the environment.Improving fertilizer utilization rate is the goal of accurate nutrient management.Although the current strategies and methods of nutrient management have improved fertilizer utilization rate to a certain extent,there is a lack of methods to predict the fertilizer utilization rate.Soil feed fraction is closely related to fertilizer utilization rate,and improving fertilizer utilization rate is essentially to control soil feed fraction at the optimal level.This study from 2006-2007 mainly maize,rice production areas in northeast China"3414"test data were analyzed,and research the most suitable for corn,rice in the northeast of the fertilizer effect function model,the accurate estimation of soil support component,to establish model of breakthrough fertilizer utilization ratio variation mechanism and the main control factors,build the nutrient management theory system and the index system,It provides theoretical basis and application guidance for accurate management of maize and rice potassium fertilizer in northeast China.The results showed that soil K supply and management level had a great impact on crop yield.In the soil with high K supply level,appropriate K input should be reduced,and reasonable nutrient management measures should be adopted to improve yield and fertilizer utilization rate.In order to ensure crop yield and quality,fertilizer application should be reasonably increased on medium and low K level soil.The ratio of K application amount to soil K supply proves that there is absorption competition between soil K and fertilizer K,which results in different K supply capacity of K fertilizer in soils with different K supply levels,which can be interpreted as K relative supply capacity（KRSC）of K fertilizer in soils with different K supply levels.K fertilizer utilization rate was strongly affected by soil K supply,and the huge variation of soil K supply was the main factor leading to the variation of K fertilizer utilization rate.Based on the analysis of the relationship between yield and K fertilizer utilization rate in K free zone under different soil K background,it was found that soil K supply had a negative effect on K fertilizer utilization rate,while the yield in K free zone had a positive effect on K fertilizer utilization rate.According to this result,the crop K starvation degree（CKSD）was defined.This study also shows that the K_S、K_Fand Y₀are the three main control factors of K fertilizer utilization,the three relative by KRSC and CKSD these two variants way decides the fertilizer utilization ratio and the common influence the K fertilizer and complement each other,only to improve to achieve the stability of potash fertilizer utilization ratio,It explained 100%and 99.8%of K utilization rate in maize and rice,respectively.The yield of Non-K yield can be increased by rational planting,improved crop varieties,pest and disease control and so on.The response of crops to K fertilizer application can be improved by improving fertilizer types,fertilization methods and nutrient management level,that is,the relative supply capacity of K fertilizer can be improved.The K fertilizer utilization rate can reach the target value by controlling CKSD and KRSC in the expected value.