Influences of 6-year Application of Biochar and Biochar-based Compound Fertilizer on Soil Bioactivity on Brown Soil
The objective of this study was to investigate the influence of application of biochar and biochar com-pound fertilizer on soil enzyme activity under test of improving brown soil for the sixth year in a row,and it also re-vealed the effect of biochar on agricultural soil micro-environment.A micro-plot (2 m2 )field experiment was con-ducted from 2009 to 2014 with peanut as tested crop.Four treatments were designed:corn straw returning in combi-nation with NPK (CS),pig manure in combination with NPK (PMC),biochar from corncob in combination with NPK (BIO),and biochar-based compound fertilizer (BF).Catalase,invertase,urease,MBC and soluble carbon of peanut were determined using their relevant methods before sawing and at different developmental stages in 2014. Before planting and mature period,the catalase activity of BIO was close to CS and PMC,the catalase of BIO was lower than that of CS and PMC.Except mature period,invertase activity of BIO was higher than CS and PMC at all growth stages of peanut.Compared with other growth stages,catalase activity of BF was higher than CS and PMC at seeding stage.Only at podding stage,soil invertase activity of treatment BF was higher than that of treatment CS and PMC.Compared with CS and PMC,BIO and BF on urease activity did not show obvious regularity.The positive effect of using biochar and biochar-based compound fertilizer on microbial activity was lower than pig manure appli-cation.Compared with CS and PMC,BIO improved the content of DOC at flowering-stage.Biochar induced catalase activity and content of DOC,but improved invertase activity.Application of biochar-based compound fertilizer in-duced catalase,invertase activity and content of DOC.Compared with CS and PMC,BIO and BF on urease activity did not show obvious regularity.Using biochar and biochar-based compound fertilizer of improve activity of microbial in the straw returned and the pig manure application.