| 摘要: |
| 通过接种土壤微生物的混合培养及土壤泥浆培养试验，测定了厌氧培养过程中Cr（Ⅵ）和Fe（Ⅱ）浓度的变化，研究了不同浓度铬酸盐的微生物还原能力及不同浓度铬酸盐对水稻土中氧化铁还原的影响。结果表明，由水稻土中提取的微生物虽然能够直接还原Cr（Ⅵ），但其还原速率和还原程度有限，且Cr（Ⅵ）浓度越高，微生物的还原能力越差；不同来源的土壤微生物对Cr（Ⅵ）的还原能力有所差异，其中四川水稻土中微生物对Cr（Ⅵ）的还原能力均大于江西水稻土；往仄氧培养的水稻土中，添加的Cr（Ⅵ）可以较迅速地还原，其中土壤氧化铁的微生物还原过程对Cr（Ⅵ）还原具有明显的促进作用；Cr（Ⅵ）的存在导致Fe（Ⅱ）生成的时间出现滞后，且Cr（Ⅵ）浓度越大生成Fe（Ⅱ）的滞后时间越长；Fe（Ⅱ）产生滞后的时间与Cr（Ⅵ）还原结束的时间具有一致性。 |
| 关键词: 微生物Cr(Ⅵ)还原 异化Fe(Ⅲ)还原 水稻土 |
| DOI： |
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| 基金项目:国家自然科学基金项目（40271067）；教育部博士学科点专项科研基金项目（20020712009） |
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| Reduction capabilities of microbial Cr(Ⅵ) in anaerobic environment |
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| Abstract: |
| The changes of Cr(Ⅵ) and Fe(Ⅱ) concentration were measured during Co-culture experiment and slurry experiments.The microbial reducing ability of different chromate concentrations and the effect of chromate on dissimilatory iron reduction in paddy soil were investigated.The result indicated that,although microorganism from paddy soil could directly reduce Cr(Ⅵ),the reduecing rate and efficiency were limited;the higher Cr(Ⅵ) concentration was,the less reducing ability the microbial showed;the microbe from different paddy soils had different effects on Cr(Ⅵ) reducing abilities;The reducing ability of the microbe from Sichuan paddy soil was higher than that from Jiangxi paddy soil.Cr(Ⅵ) added could be rapidly reduced in paddy soil under anaerobic incubation,moreover,the process of dissimilatory iron reduction of soil could obviously promote the Cr(Ⅵ) reduction.The existent of Cr(Ⅵ) could delay the appearance of Fe(Ⅱ);the higher Cr(Ⅵ) concentration was,the later Fe(Ⅱ) appeared.The delayed time of Fe(Ⅱ) appearance was in accordance with the ending time of Cr(Ⅵ) reduction. |
| Key words: microbial Cr(Ⅵ) reduction dissimilatory iron reduction paddy soil |
