Analysis Of Soil Nutrient Status And Establishment Of Recommended Fertilization Index System For Corn In Plain Area Of Tongliao

Tongliao,as the main corn production area in Inner Mongolia Autonomous Region,has a stable corn planting area of more than 1 million hm2.With the increase of corn planting years and the continuous application of a large amount of chemical fertilizers,pesticides and herbicides during the cortn planting process,it will inevitably lead to changes in soil physical and chemical properties,which makes traditional fertilizer management techniques unable to meet the needs of high-yield corn cultivation.Based on this,this paper first investigated the current status of soil nutrients in the plain area of Tongliao,and combined with the fertilization experiment of "3414" plots in corn,analyzed the changes of soil available nutrients(nitrogen,phosphorus,potassium)and corn yield in the corn planting area of Tongliao Plain According to the research,the index system of corn fertilization in the plain area of Tongliao was initially established to provide a scientific basis for the high-yield cultivation of corn.The main research results obtained in this paper are as follows:The content of soil organic matter in the plain area of Tongliao City is mainly at Level 3,accounting for 90.1%of the cultivated land area;the content of total nitrogen is mainly at Level 3 and level 4,accounting for 75.5%and 23.5%of the cultivated land area;the content of alkali hydrolyzed nitrogen is mainly at level 4,accounting for 92.9%of the cultivated land area;the content of soil available phosphorus is mainly at Level 3 and level 4,accounting for 76.1%of the cultivated land area respectively 1%and 23.9%;the content of available potassium is mainly at Level 3,accounting for 83.4%of the cultivated land area;the pH value of soil is mainly at level 2,accounting for 66.5%of the cultivated land area.In the plain area of Tongliao,the yield of maize nitrogen,phosphorus and potassium fertilizer is 41.9%,the efficiency of nitrogen fertilizer is 17.0%,the efficiency of phosphorus fertilizer is 8.0%,and the efficiency of potassium fertilizer is 16.9%;The agronomic efficiency of nitrogen,phosphorus and potassium fertilizer is 8.4 g·kg-1,of which nitrogen fertilizer has the largest yield increase effect,and the agronomic efficiency is 9.2 g·kg-1,followed by potassium fertilizer.The effect of increasing yield is the smallest,and the agronomic efficiency is 6.4 g·kg-1.The indicators of maize soil nutrient abundance in the plain area of Tongliao were determined.Alkaline nitrogen:very low(<23 mg·kg-1),low(23-73 mg·kg-1),medium(73-143 mg-kg-1),high(143-179 mg·kg-1),extremely high(>179 mg·kg-1);available phosphorus:extremely low(<1.5 mg·kg-1),low(1.5-3 mg·kg-1),medium(3-13 mg·kg-1),high(13-26 mg·kg-1),extremely high(>26 mg-kg-1);available potassium:extremely low(<41 mg·kg-1),low(41-87 mg·kg-1),medium(87-179 mg·kg-1),high(179-337 mg·kg-1),extremely high(>337 mg·kg-1).The model between the measured value of soil nutrients and the optimum fertilization in the plain area of Tongliao is:YN=-53.551n(XN)+388.99,YP=-52.431n(XP)+224.45,YK=-36.0211n(XK)+237.18.The reasonable amount of nitrogen fertilizer for maize nitrogen fertilizer in the plain area of Tongliao is:soil alkaline nitrogen content>179 mg·kg-1,recommended nitrogen fertilizer application amount is 120 kg·hm-2,and alkaline nitrogen content 143-179 mg·kg-1,The recommended nitrogen fertilizer application rate is 120-130 kg·hm-2;the alkaline nitrogen content is 73-143 mg·kg-1;the recommended nitrogen fertilizer application rate is 130-165 kg·hm-2;the alkaline nitrogen content is 23-73 mg·kg-1,the recommended nitrogen fertilizer application rate is 165-225 kg·hm-2;the alkali nitrogen content is less than 23 mg·kg-1,the recommended nitrogen fertilizer application rate is 225 kg·hm-2.The reasonable fertilizer application rate of corn phosphate fertilizer in the plain area of Tongliao is:soil available phosphorus content>26 mg·kg-1,recommended application rate of phosphate fertilizer is 60 kg·hm2;available phosphorus content 13-26 mg·kg-1,recommended phosphate fertilizer The application rate is 60-90 kg·hm-2;the effective phosphorus content is 3-13 mg·kg-1;the recommended phosphorus fertilizer application rate is 90-195 kg·hm-2;the effective phosphorus content is 1.5-3 mg·kg-1,The recommended phosphorus fertilizer application rate is 195-225 kg·hm-2;the effective phosphorus content is<1.5 mg·kg-1,and the recommended phosphorus fertilizer application rate is 225 kg·hm-2.The reasonable fertilization amount of corn potassium fertilizer in the plain area of Tongliao City:soil available potassium content>337 mg·kg-1,recommended potassium fertilizer application amount is 30 kg·hm-2;available potassium content 179-337 mg·kg-1,recommended potassium fertilizer The application rate is 30-45 kg·hm-2;the available potassium content is 87-179 mg·kg-1;the recommended potassium fertilizer application amount is 45-75 kg·hm-2;the available potassium content is 41-87 mg·kg-1,The recommended potassium fertilizer application rate is 75-105 kg·hm-2;the available potassium content is<41 mg·kg-1,and the recommended potassium fertilizer application rate is 105 kg·hm-2.