산불이 토양 미생물 군집과 효소 활성 변화에 미치는 영향

Abstract

Fire can affect microbial community structure of soil through altered environmental conditions, nutrient availability, and biotic source for microbial re-colonization. We examined the influence of fire on chemical properties and soil enzyme activities of soil for 10 months. We also characterized the soil microbial community structure through ester-linked fatty acid analysis (EL-FAME). For this study, we established five burned plots (1*1 m) and 5 unburned plots outside the margin of fire. Soil was sampled three soil cores in a each plots and composited for analysis at 1, 3, 5, 8, and 10 month after fire. The fire caused an increase in soil pH, exchangeable Ca, and Mg, organic matter, available P2O5 compared to unburned sites. The content of NH4-N in burned site was significantly higher than that of unburned site and this effect continued for 8 months after fire. There was no difference of NO3-N content in soil between burned and unburned site. Fire caused no change in acid phosphatase and arylsulfatase activities but β- glucosidase and alkaline phosphatase activities in burned site were increased compared to unburned site. Microbial biomass as estimated by total concentration of EL-FAMEs in burned sites was significantly higher than that of unburned sites at one month after fire. Burned site decreased the EL-FAMEs indicative of gram-positive bacteria and tended to increase the fatty acid associated with gram-negative bacteria at one and three months after fire. The sum of EL-FAME compound 18:2ω6,9c and 18:1ω9c as served fungal biomarkers was decreased in burned site compared to unburned site.