Soil Nutrients Variability In Corn Main Producing Areas And Fertilization Recommendation Of Corn In Liaoning Province

The research was aimed at the problem in corn nutrition management in main corn producing areas in Liaoning province,implemented a systematic study on corn nutrition management,soil nutrients status and variability,fertilization recommendation techniques.data collection methods was used production investigation,field trials and lab analysis,data analysis methods was adopted traditional Statitics and Geostatitics.The results were summarized as follows:1.Soil utrient variability trend of Liaoning was S＞Fe＞P＞Mn＞Zn＞B＞Mg＞Cu＞NH₄⁺-N＞OM＞K＞Ca＞pH.variability trend of soil nutrient in south,north and west of liaoning was P＞S＞Zn＞B＞Mn＞Fe＞Mg＞NH₄⁺-N＞OM＞Cu＞Ca＞K＞pH,S＞NH₄⁺-N＞P＞Fe＞OM＞Mn＞Zn＞Mg＞Cu＞B＞Ca＞K＞pH and S＞FeP＞Mn＞Zn＞B＞Mg＞Cu＞NH₄⁺-N＞OM＞K＞Ca＞pH, respectively.In addition,there was correlation among soil nutrients.2.Most of soil was fit for corn production,soil pH was 5.5-8.5,organic matter content was medium or low level.Deficient proportion of nutrients was NH₄⁺-N 41.7%,P 65.6%,K 72.9%,Mg7.3%,S82.1%,B6.6%,Cu4.6%,Fe 26.5%,Mn 3.3%and Zn 69.5%,respectively.some corn regions showed Ca,S,Cu,Zn excessive.3.Compared from different regions,soil was neutral or weak acid in south of Liaoning, weak acid in north of Liaoning,neutral or weak alkaline in west of Liaoning.Organic matter content was high in north of Liaoning and low in west of Liaoning,NH₄⁺-N content was more deficient in north and west of Liaoning than south of Liaoning,Available P content was more deficient in south and west of Liaoning than north of Liaoning.Soil available K was seriouslly deficient.in three main corn producing area,Micro-nutrients content in west of Liaoning was lower than that in south and north of Liaoning.4.Soil pH,NH₄⁺-N,available P,B,Mn had significant spatial self-correlation,spatial variability resulted from structure factors,such as soil mother material,climate,terrain,etc. Other nutrients had medium spatial self-correlation,spatial variability resulted froms tructure factors.Spatial variability model of available P,K,Ca,Mg and S was exponential model,Soil pH,OM,NH₄⁺-N,available B,Cu,Fe,Mn,Zn was spherical model,model of OM,K,Ca,B, Cu,Fe,Mn fit better.5.Using Geostatitics analysis method and ASI,Soil OM content was medium in 71.7% soil in main corn produing areas in Liaoing,soiL pH was suitable to corn plant,NH₄⁺-N content was medium,deficient area occupied 18.8%,available P,K,S,Zn content was low,deficient area was 50.1%,77.2%,79.4%and 61.4%,respectively,available Ca,Mg,B and Mn was rich,available Fe content was medium or high level and deficient area was 11.5%. 6.Seen from distribution map of soil nutrients,nutrients status was best in north of Liaoning,most of soil was weak acid,soil OM,NH₄⁺-N and available P content was medium, available Ca,Mg,S,B,Cu,Fe,Mn was rich,K deficient area proportion was about 1/3.South of Liaoning followed,soil pH was about neutral,OM content was medium,most of soil was medium in NH₄⁺-N,available P and S,part of soil was deficient,available Kwas deficient in total soil,available Ca,Mg,B,Cu,Fe,Mn was rich.West of Liaoning was the worst,soil pH was neutral or weak alkaline in half soil,others was weak acid or weak alkaline,soil OM content was low in half soil,NH₄⁺-N content was medium,available P and Zn was low, deficient area was about 2/3 in available K,available Fe was deficient in part of soil,other nutrients was rich.different fertilizer action should be taken according to soil nutrient status of three corn producing areas.7.The investigation results of fertilization situation were::The corn with Urea,Complex fertilizer,Diammonium phosphate and organic fertlizer were 84.6%,80.3%,40.1%and 34.2%,respectively.Seen from fertilizer rate in different regions,Urea rate was about same, Diammonium phosphate rate was north of Liaoning＞west of liaoning＞south of Liaoning, Complex fertilizer rate was north of Liaoning＞south of Liaoning＞west of liaoning,organic fertlizer rate was west of liaoning＞north of Liaoning＞south of Liaoning8.The average N,P₂O₅ and K₂O application rates on corn were 234.4 kg/hm²,104.8 kg/hm² and 53.5kg/hm² in Liaoning,respectively.Most of the total fertilizer amount was from chemical fertilizer.N,P₂O₅ and K₂O application rates were different in differet corn areas, N,and P₂O₅ application rates were north of Liaoning＞west of liaoning＞south of Liaoning, K₂O application rates were south of Liaoning＞north of Liaoning＞west of liaoning.The ratio of P₂O₅ and K₂O was low,especially K₂O rate was too low.K₂O application rates and ratio were high under high corn yield level.9.The results showed that N fertilization increased yield by 13.1%～21.9%,P by3.2%～21.5%,K by 2.7%～42.8%,respectively.N fertilization increased profit by 192～1791 yuan/hm²,P by 96～1908 yuan/hm²,K by 84～2302 yuan/hm².N,P,K uptake rate was increased with N,P,k fertilizer application,N,P,K utilization efficiency was decrased with application rate increasing.10.Economic optimum fertilizer rate was N168～170 kg/hm²,235～251 kg/hm² and 155～206kg/hm²,P₂O₅77～101kg/hm²,78～98kg/hm² and 83～100kg/hm²,K₂O73～125kg/hm²,67～110 kg/hm² and 97～100kg/hm² in Haicheng,Changtu and Zhangwu,respectively.11.Balanced fertilization improved corn yield and profit,but also nutrients uptake increased.N application rate should decreased,K application rate should increased and P application rate shoud maintained.