Effects of long-term application of biochar on physicochemical properties and wheat yield in fluvo-aquic soil
[Objective]The effects of biochar application on the physical and chemical properties of luvisol soil and wheat yield after 12 years of successive application were scientifically evaluated,aiming to provide a theoretical basis for biochar scientific application in the luvisol farmland of North China.[Method]In this study,four straw biochar treatments,including BC0(0 t·hm-2),BC1(2.25 t·hm-2),BC2(6.75 t·hm-2)and BC3(11.25 t·hm-2),were carried out in a typical fluvial soil farmland of wheat-maize rotation in North China.After 12 years of application,the soil porosity,field water holding capacity,soil bulk density,soil organic carbon,soil total nitrogen,soil aggregate stability and wheat yield components for the 2022-2023 season were systematically analyzed.[Results]Long-term application of biochar had a great impact on the physicochemical properties of soil.Compared with BC0,BC1,BC2 and BC3 treatments significantly increased total porosity by 6.82%,20.45%and 27.27%,capillary porosity by 4.55%,9.09%and 22.73%,aeration porosity by 4.35%,26.09%and 30.43%,and field water holding capacity by 14.57%,43.09%and 80.11%,while sig-nificantly reduced soil bulk density by 7.14%,22.86%and 32.86%.In addition,long-term biochar application significantly improved the soil organic carbon,total nitrogen content and the stability of aggregates.Compared with BC0,BC1,BC2,and BC3 treatments increased soil organic carbon by 71.04%,206%and 130.16%,total nitrogen content by 8.46%,104.35%and 42.68%,mean weight diameter(MWD)by 62.61%,118.28%and 116.95%,geometric mean diameter(GMD)by 17.21%,19.86%and 2.45%,and large aggregates(R>0.25 mm)by 2.00%,5.12%and 2.12%,with BC2 showing the largest improvement.Application of biochar also significantly improved the grain yield of wheat,with BC1,BC2,and BC3 treatments increasing by 5.93%,8.16%and 12.49%compared with BC0 treatment.Pearson correlation analysis showed that wheat yield was greatly affected by aggregate stability and soil fertility.There was a significant positive correlation between wheat yield and both MWD value and soil organic carbon content,and R>0.25 mm was significantly positively correlated with organic carbon and total nitrogen.[Conclusion]After successive addition of biochar for 12 years,soil fertility and wheat grain yield were improved by enhancing soil physical and chemical properties,and the biochar dosage of 6.75 t·hm-2 had a better effect.
biocharsoil aggregationsoil porositysoil organic carbonsoil total nitrogengrain yield
万方数据
维普
