| 不同稻作系统土壤的CH4产生潜力与产生途径 |
| 摘要点击 1459 全文点击 554 投稿时间：2021-10-27 修订日期：2021-12-06 |
| 查看HTML全文
查看全文 查看/发表评论 下载PDF阅读器 |
| 中文关键词 乙酸产CH4途径 土壤性质 稻田生态系统 氟甲烷 稳定性碳同位素组成 |
| 英文关键词 acetoclastic methanogenesis soil properties paddy ecosystem fluoromethane stable carbon isotope composition |
| 作者 | 单位 | E-mail | | 沈皖豫 | 中国科学院南京土壤研究所, 土壤与农业可持续发展国家重点实验室, 南京 210008
中国科学院大学, 北京 100049 | shenwanyu@issas.ac.cn | | 黄琼 | 中国科学院南京土壤研究所, 土壤与农业可持续发展国家重点实验室, 南京 210008
中国科学院大学, 北京 100049 | | | 马静 | 中国科学院南京土壤研究所, 土壤与农业可持续发展国家重点实验室, 南京 210008 | | | 张广斌 | 中国科学院南京土壤研究所, 土壤与农业可持续发展国家重点实验室, 南京 210008 | gbzhang@issas.ac.cn | | 徐华 | 中国科学院南京土壤研究所, 土壤与农业可持续发展国家重点实验室, 南京 210008 | |
|
| 中文摘要 |
| 不同稻作系统土壤的CH4产生潜力，特别是CH4产生途径（主要为乙酸发酵和CO2/H2还原）间的差异尚不明确.通过添加与不添加氟甲烷（CH3F）抑制剂（添加比例分别为2%和0%）的土壤厌氧培养试验，并采用稳定性碳同位素等方法，对我国3类典型稻田生态系统（稻-麦轮作，RW；稻-休闲，RF；双季稻，DR）土壤CH4产生累积浓度、CH4产生潜力、溶解性有机碳（DOC）含量、乙酸含量和乙酸产CH4的相对贡献率（fac值）进行了对比研究.结果表明，RF的CH4产生潜力为7.18 μg ·（g ·d）-1，显著低于RW［10.33 μg ·（g ·d）-1］和DR［13.42 μg ·（g ·d）-1］（P<0.05）；相关分析表明，CH4产生潜力与土壤阳离子交换量及pH呈显著负相关（P<0.01）；添加CH3F显著抑制CH4产生（P<0.05）.DR的ω（DOC）和ω（乙酸）分别为255 mg ·kg-1和7.34 mg ·kg-1，较RW和RF分别高17%~51%和22%~23%（P<0.05）.δ13 CH4和δ13 CO2值受稻作系统的影响显著，其中，RF的δ13 CH4值最大（-43.89‰），较RW和DR分别偏正11.06‰和8.33‰（P<0.05）；而其δ13 CO2值最小（-26.30‰），较RW和DR分别偏负7.63‰和5.14‰（P<0.05）.RW和RF的α（CO2/CH4）值分别为1.057和1.058，显著低于DR的1.062（P<0.05）.RF的fac值为84%~98%，较RW和DR分别高34%~38%和20%~23%（P<0.05）. |
| 英文摘要 |
| Differences inmethane (CH4) production potential in paddy soils under different rice-based cropping systems and especially in the methanogenic pathways (mainly acetate fermentation and CO2/H2 reduction) remain unclear. Anaerobic incubations of soil with or without fluoromethane (CH3F) inhibitor (2% and 0%) were conducted. With the soils from three typical paddy ecosystems (rice-wheat rotation, RW; rice-fallow, RF; double-rice, DR) in China, the cumulative concentration of CH4 production, CH4 production potential, dissolved organic carbon (DOC) content, and acetic acid content were determined. Meanwhile, the relative contribution of acetate-dependent methanogenesis (fac) was quantified using the stable carbon isotope method. The results showed that the CH4 production potential was 7.18 μg·(g·d)-1 in RF, which was significantly lower than that in RW[10.33 μg·(g·d)-1]and DR[13.42 μg·(g·d)-1] (P<0.05). Correlation analysis showed that CH4 production potential was significantly negatively correlated with soil cation exchange capacity and pH (P<0.01); the addition of CH3F significantly inhibited CH4 production (P<0.05). The content of DOC and acetic acid in DR were 255 mg·kg-1 and 7.34 mg·kg-1, respectively, which were 17%-51% and 22%-23% higher than those in RW and RF, respectively. The δ13CH4 and δ13CO2 values were affected greatly by different rice-based cropping systems, and the highest δ13CH4 value was -43.89‰ in RF, which was more positive than that of RW and DR by 11.06‰ and 8.33‰, respectively (P<0.05). By contrast, the lowest value of δ13CO2 was observed in RF, which was more negative than that of RW (7.63‰) and DR (5.14‰) (P<0.05). The α(CO2/CH4) values of RW and RF were 1.057 and 1.058, respectively, which were significantly lower than 1.062 in DR (P<0.05). The fac values of RF ranged from 84% to 98%, being 34%-38% and 20%-23% higher than those of RW and DR, respectively (P<0.05). |
|
|
|
