Effects of different manure management practices on soil carbon and basal respiration
不同施肥管理措施对土壤碳含量及基础呼吸的影响

A 7-year field experiment of different fertilizers EM compost(15t/hm2,7.5t/hm2),EM chicken manure compost(15t/hm2,7.5t/hm2),traditional compost(15t/hm2,7.5t/hm2),chemical fertilizer(750kg/hm2 ammonium bicarbonate,300kg/hm2 urea,750kg/hm2 calcium super-phosphate)and control] was conducted to study the effects of different manure management practices on soil carbon content and basal respiration.Results show that soil dissolvable carbon,total organic carbon,microbial biomass carbon and basal respiration rates increase when the amount of applied organic manure increases.Applied chemical fertilizer slightly enhances soil dissolvable carbon,total organic carbon,microbial biomass carbon and basal respiration in a somewhat insignificant amount.Observed trend of soil organic carbon,microbial biomass carbon and basal respiration in the treatments is:controlchemical fertilizer>traditional compost>EM compost.Soil microbial metabolic quotient has a negative correlation with soil dissolvable carbon,total organic carbon,microbial biomass carbon and basal respiration rate.