Title Page
ABSTRACT
국문 초록
Contents
CHAPTER 1. INTRODUCTION 14
CHAPTER 2. MATERIAL AND METHODS 17
2.1. Synthesis of ferrihydrite 17
2.2. Microcosms set up 17
2.3. Geochemical analysis 20
2.4. Microbial community analysis 21
CHAPTER 3. RESULTS 22
3.1. Changes in pH, and the concentrations of electron acceptors and donors at 18℃ and 50℃ 22
3.2. Microbial community analysis 24
3.3. Chemical and microbial analysis of control conditions at 18℃ and 50℃ 29
CHAPTER 4. DISCUSSION 32
4.1. Microbial reactions and activities at 18℃ 32
4.2. Microbial reactions and activities at 50℃ 37
4.3. Microbial reactions and activities at 50℃ control 41
CHAPTER 5. CONCLUSION 43
REFERENCES 47
Table 1. The matrix of experimental design of this study 18
Table 2. The matrix of control condition design of this study 19
Table 3. Concentration of organic acids, sulfate and iron corresponding to diverging point based on main reaction 33
Table 4. The biogeochemical reactions described in this study 34
Fig. 1. (A) The contents of water, organic matter and organic carbon in bentonite determined by the loss-on-ignition method. (B) The concentration of dissolved organic carbon, sulfate,... 21
Fig. 2. Variation of chemistry at 18℃ condition enrichment experiments. Concentration of lactate (A), acetate (B), propionate (C), sulfate (D), total FeII (E), and aqueous FeII (F) and...[이미지참조] 23
Fig. 3. Variation of chemistry at 50℃ condition enrichment experiments. Concentration of lactate (A), acetate (B), propionate (C), sulfate (D), total FeII (E), and aqueous FeII (F) and...[이미지참조] 24
Fig. 4. The change of relative abundance of microorganisms at the phylum level (over than 3%) during the entire experimental period at 18℃ and 50℃ temperature conditions. 26
Fig. 5. The microbial community developments during over experimental time. The size of each circle represents the relative abundance of each microbe and colored circles indicate... 28
Fig. 6. Comparison of microbial beta diversity based on 3D-PCoA plot of microbialc ommunity using jaccard distance method. 29
Fig. 7. Variation of chemistry at 18℃ and 50℃ condition control experiments. Concentration of lactate (a), acetate (b), propionate (c), sulfate (d), total FeII (e), and aqueous FeII (f) and...[이미지참조] 30
Fig. 8. Heatmap representing the change of microbial community composition of 50C4 condition. 31
Fig. 9. The color change of each treatment corresponds to a specific phase of the main reaction during the incubation period at 18℃ conditions. 36
Fig. 10. The color change of each treatment corresponds to a specific phase of the main reaction during the incubation period at 50℃ conditions. 41
Fig. 11. Metabolic model of indigenous microbes in WRK bentonite at 18℃ conditions. 44
Fig. 12. Metabolic model of indigenous microbes in WRK bentonite at 50℃ conditions. 45