论文部分内容阅读
以我国6个省的水稻土为供试样品,采用厌氧恒温培养方法,研究了分别以葡萄糖、丙酮酸盐、乳酸盐和乙酸盐为惟一碳源时不同淹水时间土壤微生物群落对Fe(Ⅲ)的还原能力.结果表明:不同淹水时间对Fe(Ⅲ)还原特征值Vmax的影响显著,表现为淹水20d>30d>12d>1d>5d,不同淹水时间下水稻土微生物群落结构不同是导致Fe(Ⅲ)还原能力不同的主要原因.不同碳源对微生物铁还原过程有显著影响,葡萄糖和丙酮酸盐在不同淹水时间中始终为优势碳源,其Fe(Ⅲ)还原率分别为88.1%～99.9%和58.0%～97.9%;不同土壤铁还原微生物群落对乳酸盐的利用差距较大,湖南和浙江水稻土在整个淹水周期中Fe(Ⅲ)还原率达到87.1%～100%,而其他土壤则表现为淹水前5d为5.0%～49.4%,12d后增加到52.2%～99.9%;乙酸盐处理在不同淹水时间中都表现为随时间推移Fe(Ⅲ)还原率逐渐增大的趋势,其中浙江水稻土的变化最大,在5.3%～75.8%.
Taking paddy soils of six provinces in China as test samples, the anaerobic thermostatic culture method was used to study the effects of different flooded soil microbial communities on glucose, pyruvate, lactate and acetate as carbon sources Fe (Ⅲ). The results showed that: flooding time significantly affected the characteristic value of V (subscript Fe) reduction of Fe (Ⅲ), indicating that the flooding time was 20d> 30d> 12d> 1d> Different carbon sources lead to different reducibility of Fe (Ⅲ) .The different carbon sources have a significant effect on the reduction of microbial iron. Glucose and pyruvate have always been the dominant carbon sources in different flooding time. Fe (Ⅲ) The reduction rates were 88.1% -99.9% and 58.0% -97.9%, respectively. The difference of lactate utilization by iron reduction microbial communities in different soils was large. The reduction rates of Fe (Ⅲ) in paddy soils of Hunan and Zhejiang during the whole flooding cycle reached 87.1% ~ 100%, while that of other soils was 5.0% ~ 49.4% 5 days before flooding, and increased from 52.2% ~ 99.9% after 12 days. The acetate treatment showed different degrees of flooding over time (Ⅲ) reduction rate gradually increased trend, of which Zhejiang paddy soil changes the most, At 5.3% ~ 75.8%.