Effect Of Biochar Pyrolysed In Different Temperatures On The Fertilizer-holding Of Tobacco Planting Soil

Biochar is a substance made from crop waste carbon-rich through high temperature pyrolysed under the condition of hypoxia.It is stable,and has developed pore structur large specific surface area and abundant surface functional groups.Tobacco were planted in a glass greenhouse with the lysimeter,to research dynamic effect of the interaction between biochar pyrolysed temperature?include 360? and 500??and soil texture?include loam soil and sandy soil?on soil ammonium nitrogen and nitrate nitrogen's amount?include 0-30 cm layer?.The results showed that:1)In the sandy soil,low-temperature pyrolysed biochar application increased the amount of NH₄⁺-N by22.32% compared to contrast group which mainly occured in the 0-10 cm soil layer and the high-temperature pyrolysed biochar was 10.79% lower.2)The NH₄⁺-N 's amount in loam soil is lower than sandy soil significantly.NH₄⁺-N's content under two kinds of biochar treatment had no significant difference compared to contrast group in which the low-temperature pyrolysed biochar acted more obvious.3)The application of biochar increased the amount of NO₃^--N in soil.Low-temperature pyrolysed biochar application increased by 20.58% compared to contrast group and the high-temperature pyrolysed biochar was 8.97% higher.Low-temperature pyrolysed biochar is better than high-temperature pyrolysed biochar in NO₃^--N retention capacity in soil.4)The NO₃^--N 's amount in loam soil or sandy soil is 16.09% or 29.18% higher than contrast group,which showed that low-temperature pyrolysed biochar application could improve the fertilizer retention capacity of sandy soil more.The nitrate nitrogen's amount in loam soil or sandy soil is 11.03% or 4.97% higher than contrast group,which showed that high-temperature pyrolysed biochar application could improve the fertilizer retention capacity of loam soil more.5)The application of biochar could promote the growth and development of tobacco significantly,and the effect of 360? pyrolysed biochar was better than that of500? pyrolysed biochar.In the 30 th day,the plant height,leaf number is significantly higher than contrast when tobacco was planted in loam soil.In the 90 th day,the plant height,the largest leaf length is significantly higher than contrast when tobacco was planted in loam soil.6)The application of biochar could reduce the apparent loss of total nitrogen of the soil-tobacco system,and the effect of 360? pyrolysed biochar was better than that of 500? pyrolysed biochar.The NALs of each treatment?fertilized +low-temperature pyrolysed biochar application in loam soil,fertilized + high-temperature pyrolysed biochar application in loam soil,fertilized + low-temperature pyrolysed biochar application in sandy soil,fertilized + high-temperature pyrolysed biochar application in sandy soil?was decreased by 99.59%,29.82%,81.26% and 70.67% compared with each fertilization treatment,and appeared significant differences.The conclusion is : the application of biochar could increased the amount of NO₃^--N in soil,and the effect of360? pyrolysed biochar was better than that of 500? pyrolysed biochar.The application of 360? pyrolysed biochar could increased the amount of NH₄⁺-N in sandy soil while the application of 500? pyrolysed biochar could decreased it.The NH₄⁺-N 's amount in loam soil is lower than sandy soil significantly.NH₄⁺-N's amount under two kinds of biochar treatment had no significant difference compared to contrast group in the loam soil.The application of biochar could promote the growth and development of tobacco significantly,and the effect of 360? pyrolysed biochar was better.The application of biochar could reduce the apparent loss of total nitrogen of the soil-tobacco system.