Effect of microorganism on the degradation and formation of humic acid in Landfill Leachate

摘要

Humic acids are natural non-living organic substances and they are extremely resistant to biodegradation. Microorganisms are the driving force behind the transformation and mineralization of humic acids. However, their relative abundance and role during turnover of humic acids in landfill leachate treatments are still unclear, there is still a gap in our knowledge. This work was therefore undertaken with the aim of investigating the role of landfill leachate microbial communities in humic acids transformation and to highlight the problems, unsolved questions in leachate treatment. The quantities of humic acids and its ratio of E4/E6 in leachate were tested in the different cultivation condition. The results shown: Compared with the blank, the formation and transformation of HA in different species are not the same, and 2,3,4 strain has a role in the degradation of HA respectively., while number 1,5 strain has promoted the formation of HA. Five leachate dominant species: Bacillus sp.1; Bacillus sp.2; Bacillus sp.3; Pseudomonas sp.4; Pseudomonas sp.5(1) In the condition of carbon source, the microorganism can synthesize the carbon source to synthesize the humus, and when the carbon source is lack, it can degrade the humus, which can be used as the nutrient substance.(2) Under the different dilution degrees, microorganisms have different ability to degrade humus.(3) The microorganisms in the leachate have the ability to degrade humic substances, can be changed the environment in the leachate, so as to achieve the purpose of reducing the humus in the leachate, and ultimately to reach the standard.