Abstract:

Functional microbes, peat, and aquifer medium were used to construct biobarrier for in-situ remediation of diesel contaminated groundwater. The system removal efficiency of target contaminants could reach 83.60%-99.85% during the 80 day steady operation. FDA-MPN and Biolog methods were adopted to study the quantity and community diversity of the functional microbes at different positions in biobarrier after the complete operation. The results indicated that each part of biobarrier had abundant functional microbes, and the microbial community in the structures had a resemblance in species, richness, homogeneity, carbon source utilization, and catabolic characteristics. However, the structure of microbial community decreased a little as biobarrier became deeper, as the proportion of functional microbes decreased, the microbial community became richer, the homogeneity got worse, and utilization tendency of carbon showed differently. The functional microbes in biobarrier could maintain relatively higher microbial quantity, degradatable properties and stable community diversity for a long time. Whereas, with nutrients structure changed deeper in biobarrier, community diversity structure of functional microbes showed a little differently when system in-situ remediate diesel contaminated groundwater.

Key words: biobarrier;groundwater, functional microbe, Biolog method, community diversity