| Microbial degradation of hydrocarbons in contaminated soil is improved by compost application, making compost a potential amendment for bioremediation of recalcitrant CCME fraction 3 and 4 (>C16) hydrocarbons. Compost application increases soil organic matter content, nutrient status and soil aeration, thus stimulating microbial populations and in turn improving soil structure.; The effects of compost amendment, with and without fertiliser additions, on microbial communities associated with crude oil bioremediation was studied in a simulated in situ field trial in Edmonton, Alberta over 14 months. With 20% dw compost application, aerobic heterotrophic and aliphatic hydrocarbon-degrading microorganisms, microbial biomass carbon, aerobic respiration rate and microbial community diversity and richness were greatly increased as hydrocarbons decreased. Ammonium sulphate fertiliser suppressed microbial community growth and activity by acidifying soil, but this effect was buffered by compost co-application. Aliphatic hydrocarbon-degrading microorganism population size, microbial biomass carbon and aerobic respiration rate were positively correlated with petroleum hydrocarbon degradation. |
