Effects of different fertilization on red soil microbial biomass C in tea garden
不同培肥措施对红壤茶园土壤微生物量碳的影响

The study on the dynamics of red soil microbial biomass C in tea garden after 4 years different fertilization showed that straw mulching combined with applying organic manure and chemical fertilizer,intercropping white clover,and applying chemical fertilizer could all increase the amount of soil microbial biomass C significantly.The annual variations of soil microbial biomass C all presented the tendency of low-high-low-high,and the effects of fertilization varied with different periods.The annual average of soil microbial biomass C in treatments T1(straw mulching 100% organic manure),T2(straw mulching 75% organic manure 25% chemical fertilizer),T3(straw mulching 50% organic manure 50% chemical fertilizer),T4(straw mulching 25% organic manure 75% chemical fertilizer),T5(100% chemical fertilizer) and T6(intercropping white clover) were 17.05%,32.38%,32.05%,24.30%,26.23% and 24.63% higher than CK,respectively,and the differences were significant(P<0.05).Soil microbial biomass C had significant positive correlations with soil active organic matter,total nitrogen,and microbial biomass N and P,but no significant correlations with soil available nitrogen,total phosphorus,total potassium,and moisture content.In comparing with applying chemical fertilizer or organic manure alone,their combination was more advantageous in improving soil fertility.