太湖不同水域沉积物甲烷释放潜力及其途径分析

为明确太湖不同湖区CH₄释放特征与释放潜力差异,采用水-气界面甲烷排放通量测定和室内厌氧培养,结合沉积物理化因子对太湖沉积物CH₄释放特征及其释放潜力差异进行研究。结果表明,不同湖区水-气界面CH₄排放通量存在显著差异;不同湖区、不同深度沉积物中CH₄释放潜力也存在明显差异,且CH₄释放潜力与含水率和总有机碳呈正相关,与盐度呈负相关;太湖沉积物产CH₄潜力最大的途径为甲基途径,且主要集中在沉积物10~35cm深度。由此可知,太湖是CH₄排放的净产生源,含水率、有机质和盐度等环境因子的差异以及沉积物深度均会影响沉积物甲烷排放和释放潜力,从而对太湖沉积系统的碳循环以及局部气候变化产生重要影响。

Analysis of Methane Release Potential and Its Pathway in Sediments from Different Water of Taihu Lake

In order to clarify the differences of CH₄release characteristics and release potential in different lakes of Taihu Lake,methane emission flux measurement at water-air interface and indoor anaerobic culture were used to study the characteristics and potential differences of CH₄release from Taihu Lake sediments combined with the physical and chemical factors of sediments,.The results showed that there were significant differences in CH₄emission fluxes from the water-air interface in different lake areas.There were also significant differences in the release potential of CH₄in sediments of different lakes and depths,and the release potential of CH₄was positively correlated with moisture content and total organic carbon,and negatively correlated with salinity.The pathway of CH₄potential of sediments in Taihu Lake was methyl pathway,which was mainly concentrated in the depth of sediment 10~35cm.It can be seen that Taihu Lake was the net source of CH₄emission,differences in environmental factors such as moisture content,organic matter and salinity as well as sediment depth affect the methane emission and release potential from sediments,thus exerting an important influence on the carbon cycle of the sedimentary system and local climate change of Taihu Lake.