Methane Emission Potential from Freshwater Marsh Soils of Northeast China: Response to Simulated Freezing-Thawing Cycles

	Methane Emission Potential from Freshwater Marsh Soils of Northeast China: Response to Simulated Freezing-Thawing Cycles
	J. Y. Wang, C. C. Song, A. X. Hou and F. M. Xi
刊名	Wetlands
	2017
卷号	37 期号:3 页码:437-445
通讯作者	宋长春
中文摘要	Boreal wetlands are significant natural sources of methane (CH4) to the atmosphere, and are vulnerable to freezing-thawing cycles (FTC). Nonetheless, the underlying factors that induce CH4 emission in boreal wetlands during FTC are still unclear. Our goal was to characterize soil CH4 emission potential from a freshwater marsh as impacted by FTC and to determine the corresponding mechanisms. We collected soil samples from two soil layers (0-20 and 2040 cm) of an undisturbed freshwater marsh in Sanjiang Plain, Northeast China, and subjected them to various freezing (6 to -6 degrees C) and thawing (-6 to 6 degrees C) cycles. Soil CH4 emission, DOC, and the aromaticity and complexity of DOC indexes were monitored. The results showed that FTC significantly increased CH4 emission potential in the 0-20 cm surface soil layer. The maximum hourly CH4 emission rate was 55.0 mg C m(-2) h(-1), approximately 19 times as high as that of the unfrozen control sample (2.8 mg C m(-2) h(-1)). However, the peak intensity of CH4 emission decreased when the numbers of FTC increased. Meanwhile, FTC not only increased the quantity of DOC released, but also enhanced its instability via increasing the contribution of relatively small, readily degradable organic molecules. Additionally, the CH4 emission potential was significantly correlated with the aromaticity and complexity of DOC, indicating that the release of labile substrates under FTC was one important factor controlling the microbial production of CH4 and the high emissions upon thawing. Our study suggested that global warming-induced increases in seasonal FTC in boreal wetlands may increase CH4 emissions beyond what would occur from long-term temperature increases alone.
内容类型	期刊论文
源URL	[http://ir.iga.ac.cn/handle/131322/7632]
专题	东北地理与农业生态研究所_湿地与全球变化学科组_期刊论文
推荐引用方式 GB/T 7714	J. Y. Wang, C. C. Song, A. X. Hou and F. M. Xi. Methane Emission Potential from Freshwater Marsh Soils of Northeast China: Response to Simulated Freezing-Thawing Cycles[J]. Wetlands,2017,37(3):437-445.
APA	J. Y. Wang, C. C. Song, A. X. Hou and F. M. Xi.(2017).Methane Emission Potential from Freshwater Marsh Soils of Northeast China: Response to Simulated Freezing-Thawing Cycles.Wetlands,37(3),437-445.
MLA	J. Y. Wang, C. C. Song, A. X. Hou and F. M. Xi."Methane Emission Potential from Freshwater Marsh Soils of Northeast China: Response to Simulated Freezing-Thawing Cycles".Wetlands 37.3(2017):437-445.