Compacted sewage sludge as a barrier for tailing impoundment: The microbial functional diversity in the compacted sludge specimen

Abstract

In order to study the feasibility and microbial mechanism of sludge barrier for acid mine drainage (AMD), the microbial functional diversity in the compacted sludge with different seepage conditions (the distilled water (DW), the pH2.1 sulfuric acid and the simulate AMD) was studied using Biolog and Most Probable Number (MPN) testing system. The results showed that the average well color development (AWCD), the Shannon index (H), the Evenness index (E), the number of positive Ecoplate wells (S), the total bacteria (TB), and the sulfate reducing bacteria (SRB) quantity differed between different seepage conditions. Compared with the DW seepage condition, the acidity and AMD condition had the lower AWCD, S, H, E values which showed the latter inhibition effect be stronger. The seepage conditions changed the microbial quantity of carbon utilization and ability to utilize the single carbon source. So the property of the microbial functional diversity in the compacted sludge might indicate the microbial differences under the different seepage conditions in this study.