Effects of returning maize straw into field on dynamic change of soil microbial biomass C,N and P under different promoted decay condition
不同促腐条件下秸秆还田对土壤微生物量碳氮磷动态变化的影响

A 2-year field experiment of wheat-maize rotation was conducted on a cinnamon soil of east Hebei Province to study the effects of returning maize straw into field on the dynamics of soil microbial biomass C,N and P,and their relationships with soil nutrients and enzyme activities.The results showed that under the condition of returning maize straw combined with applying chemical fertilizer to adjust straw C/N,the application of effective microorganisms could increase soil microbial biomass C,N and P in each crop growth period,advance their peak time,and better regulate soil nutrient supply,compared with no application of effective microorganisms.Soil microbial biomass had a significantly positive correlation with soil enzyme activities,but its correlation with soil hydrolysable N and available P was strongly affected by crop growth and fertilization system.