大气CO_2浓度升高对红松和长白赤松幼苗非根际土壤微生物的影响

Effects of Elevated Atmospheric CO_2 on Microflora in Non-rhizosphere Soil of Pinus koraiensis and P.sylvestriformis Seedlings

以连续5 a不同CO2浓度处理的长白赤松和红松幼苗为对象,采用CFU(活细胞计数)菌落计数法研究了大气CO2浓度对幼苗非根际土壤微生物数量的影响。结果表明:高浓度CO2(700μmol.mol-1和500μmol.mol-1)处理对长白赤松和红松幼苗非根际土壤细菌数量具有显著的(p<0.01)抑制作用,对真菌数量亦有抑制作用。大气CO2浓度升高对红松幼苗非根际土壤放线菌数量具有抑制作用(p<0.05),而对长白赤松幼苗土壤放线菌数量没有明显的影响。

The response of soil microflora in the non-rhizosphere soil of Pinus koraiensis and P.sylvestriformis seedlings to elevated CO2(700 and 500 μmol·mol-1) was studied.The results indicated that soil bacterial number decreased significantly(P < 0.01),and soil fungi number also decreased(P < 0.05),but not as significant as the decrease of bacterial number.The amount of soil actinomycosis decreased(P < 0.05) under elevated CO2 in the non-rhizosphere soil of P.koraiensis seedlings, however,no regularities were found between the number of actiomycetes in the non-rhizosphere soil of P.sylvestriformis seedlings and CO2 enrichment.