Abstract:
Objective The aim of the experiment was to investigate the effect of biochar-based fertilizer on soil chemical properties, enzyme activities, and microbial community in the tobacco field, and to achieve the purpose of reducing chemical fertilizer application and increasing efficiency.
Method The experiment consists of four treatments (CK: conventional nitrogen fertilizer + without biochar-based fertilizer, T1: conventional nitrogen fertilizer + biochar-based fertilizer, T2: reducing 15% nitrogen + biochar-based fertilizer, T3: reducing 30% nitrogen + biochar-based fertilizer).
Result The results showed that adding biochar-based fertilizer significantly increased the content of soil organic carbon (SOC) and microbial biomass carbon (MBC) compared with CK, by the extent of 19.68%-39.68% and 20.09%-36.14%, respectively. There was no significant effect on the activities of urease and invertase among different treatments. Conventional nitrogen dosage and 15% reduction of nitrogen combined with biochar-based fertilizer increased the average well color development (AWCD) of Biolog plates, significantly improved the utilization of carboxylic acid, phenolic acid, and amine, and enriched the microbial community structure. Principal component analysis and heatmap analysis showed that reducing 15% nitrogen and using biochar-based fertilizer had little change in the metabolic function of the microbial community compared with T1.
Conclusion Combining the effects of various treatments on soil biochemical properties, reducing nitrogen fertilizer by 15%, and applying biochar-based fertilizer (T2) has a better soil improvement effect.