Effects Of Biochar On Apple Yield,Quality And Soil Nutrient Availability

Biochar is a good soil conditioner.Its effect on soil nutrient availability and its effects on apple yield and quality are relatively few.In this paper,the effects of mixed application of biochar and special fertilizer on fruit tree and biochar base fertilizer on fruit quality of apple and the effects of biological carbon on nutrient leaching and ammonia volatilization were studied in field experiments and laboratory tests.The main results and conclusions are as follows:In the field experiment,compared with the traditional fertilization of farmers,the mixed application of biological carbon with biochar base fertilizer and fruit tree fertilizer could increase the yield of apple,and its yield increased by 30.6%-39.9%,respectively.The mixed application of biological carbon with biochar base fertilizer and fruit tree fertilizer improved the content of SPAD,total nitrogen and total potassium in apple leaves,reduced the total acidity of fruit,increased the soluble solids,Vc,hardness and coloring rate of fruit,and thus improved the quality of fruit.In the leaching experiment,under the condition of biochar base fertilizer and chemical fertilizer,when the amount of biological carbon was 3%,the nitrate nitrogen was reduced by 15.9% and 10.6% than that without biological carbon treatment,and 1.1% and 21.3% were lower than that of non-biochar treatment,when the amount of biological carbon was 6%.The results showed that biochar mixed with biochar-based fertilizer and chemical fertilizer could effectively reduce leaching loss of ammonium nitrate.Biological carbon increased the content of available phosphorus in soil,which were all significantly different from that of blank.Biochar increased the content of available potassium in soil,and the content of available potassium in 6% biochar was 4 times that of blank treatment.Biochar could increase soil total nitrogen content under both single application and other fertilizers and increase with the increase of biochar addition.It is suggested that biochar could promote the increase of available potassium and available phosphorus in soil.In the volatilization experiment,the ammonia volatilization in all treatments showed a sharp increase,then a sharp decrease and finally a gentle trend.The maximum ammonia volatilization was achieved on the third day.When the biochar addition is 6%,ammonia volatilization can be effectively reduced.When the biochar addition is 3%,watering can effectively reduce ammonia volatilization.Therefore,increasing the amount of biochar or increasing water can reduce nutrient losses and improve nutrient availability.