不同施肥管理措施对土壤碳含量及基础呼吸的影响

Effects of different manure management practices on soil carbon and basal respiration

连续7年试验研究了施用15t/hm2和7.5t/hm2有机肥(包括EM堆肥、EM鸡粪肥和传统堆肥)、化肥和对照处理对土壤碳含量与基础呼吸的影响,结果表明:随有机肥施用量的提高,土壤可溶性碳、总有机碳、微生物生物量碳和土壤的基础呼吸随之增加。施用化肥可一定程度提高土壤可溶性碳、总有机碳、微生物生物量碳和土壤的基础呼吸。不同施肥措施对土壤有机碳、微生物生物量碳和土壤基础呼吸的影响趋势为EM堆肥处理>传统堆肥处理>化肥处理>对照,施肥对土壤微生物代谢商的影响趋势为EM堆肥处理<传统堆肥处理<化肥处理<对照。土壤微生物生物量碳与可溶性碳、总有机碳及土壤基础呼吸之间呈极显著正相关。土壤微生物代谢商与土壤可溶性碳、总有机碳、微生物生物量碳及基础呼吸之间呈极显著负相关。

A 7-year field experiment of different fertilizers [ EM compost （15t/hm^2, 7.5t/hm^2）, EM chicken manure compost （ 15t/hm^2, 7.5t/hm^2 ）, traditional compost （ 15t/hm^2, 7.5t/hm^2 ）, chemical fertilizer （ 750kg/hm^2 ammonium bicarbonate, 300 kg/hm^2 urea, 750kg/hm^2 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：control〈 chemical fertilizer〈 traditional compost〈 EM compost. Soil microbial biomass carbon has a positive correlation with soil dissolvable carbon, total organic carbon and basal respiration rate. The trend of fertilization effect on soil microbial metabolic quotient is：control 〉 chemical 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.