소나무(Pinus densiflora) 생육토양의 미생물 군집에 미치는 납과 CO2의 영향

Abstract

Effects of Pb and on soil microbial community associated with Pinus densiflora were investigated using community level physiological profiles (CLPP) and 16S rDNA PCR-denaturing gradient gel electrophoresis (DGGE) methods. Two-years pine trees were planted in Pb-contaminated soils and uncontaminated soils, and cultivated for 3 months in the growth chamber where concentration was controlled at 380 or 760 ppmv. The structure of microbial community was analyzed in 6 kinds of soil samples (CA-0M : 380 ppmv + Pb 0 mg/kg + initial, CB-0M : 380 ppmv + Pb 500 mg/kg + initial, CA-3M : 380 ppmv + Pb 0 mg/kg + after 3 months, CB-3M : 380 ppmv + Pb 500 mglkg + after 3 months, EA-3M : 760 ppmv + Pb 0 mg/kg + after 3 months, EB-3M : 760 ppmv + Pb 500 mg/kg + after 3 months). After 3 months, the substrate utilization in the uncontaminated soil samples (CA-3M vs EA-3M) was not significantly influenced by concentrations. However, the substrate utilization in the Pb-contaminated soil samples (CB-3M vs EB-3M) was enhanced by the elevated concentrations. The results of principal component analysis based on substrate utilization activities showed that the structure of microbial community structure in each soil sample was grouped by Pb-contamination. The similarities of DGGE fingerprints were 56.3 % between the uncontaminated soil samples (CA-3M vs EA-3M), and 71.4% between the Pb-contaminated soil samples (CB-3M vs. EB-3M). The similarities between the soil samples under 380 ppmv (CA-3M vs CB-3M) and , 760 ppmv (EA-3M vs EB-3M) were 53.3% and 35.8%, respectively. These results suggested that the structure of microbial community associated with Pinus densiflora were sensitively specialized by Pb-contamination rather than concentration.