长期培肥黑土微生物量碳动态变化及影响因素

Dynamics of microbial biomass C in a black soil under long-term fertilization and related affecting factors

以东北典型黑土区长期采用 2种不同量有机肥 (M2 、M4)、化肥 (NPK)和不施肥 (CK) 4种方式培肥土壤为研究对象 ,对生长季微生物量碳的动态变化进行研究 .结果表明 ,施用有机肥 ,微生物量碳显著高于施用化肥和不施肥 ,容量在 6 2 0mg·kg-1以上 .在各处理中 ,微生物量碳大小顺序为M4>M2 >NPK CK .M2 、M4微生物量碳最大峰值出现在抽雄吐丝期 ,NPK最大峰值出现在播种期 ,CK最大峰值出现在蜡熟期 ,季节性变化平稳 .施肥数量和种类不同所引起的微生物量碳的差异 ,并未因季节变化及玉米生育时期影响而改变 .微生物量碳的动态变化与绝大多数黑土生物、理化特性指标动态变化无显著相关性 ;与黑土生物、理化特性 ,植物氮、磷、钾及作物籽粒粗蛋白含量之间存在较好的正相关性 .

The effect of long-term fertilization on the dynamics of microbial biomass C in a typical black soil of Northeastern China was studied in a field trail treated by different fertilizations.The results showed that the amount of soil microbial biomass C under different fertilizations varied significantly with growth stages.It was the highest in farmyard manure (M_2 and M_4) treatments,with a less seasonal fluctuation,second in NPK treatment,the peak at sowing period,and the lowest in CK,the peak at wax maturity stage.No significant correlation was found between the dynamic changes of soil microbial biomass C and soil biological,physical and chemical properties in all treatments,but the correlation of soil microbial biomass C with the contents of N,P and K in plants and that of crude protein in grain was significantly positive.