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采伐干扰是森林湿地遭受的主要干扰类型之一。采伐引起的温度和水位条件的改变,会导致森林湿地甲烷通量发生变化。本文选择小兴安岭3种森林沼泽湿地为研究对象,利用静态暗箱-气相色谱法观测它们在择伐和皆伐干扰下甲烷通量的变化,探讨采伐对天然森林沼泽甲烷通量的影响及其影响机制。结果表明:采伐前3种森林沼泽都为大气甲烷的汇(-0.19～-1.85mgm-2d-1),择伐和皆伐都导致3个类型的森林沼泽作为大气甲烷汇的功能降低(-0.22～-1.29mgm-2d-1),或者由大气甲烷的汇转变为甲烷的源(0.50～157.37mgm-2d-1)。温度和水位的共同作用导致采伐后森林沼泽甲烷通量的变化。为减少甲烷气体的排放,在有必要对森林沼泽的树木资源进行利用时,采伐方式应该尽量避免皆伐,只能进行适当的择伐。
Harvesting disturbances are one of the major types of disturbances in forest wetlands. Changes in temperature and water conditions caused by logging can lead to changes in the methane fluxes in forest wetlands. In this paper, three kinds of forest swamp wetlands in Xiaoxing’anling were selected as the research objects, and the changes of methane flux under the influence of selective cutting and clear cutting were observed by static black box-gas chromatography to explore the effect of cutting on the methane flux of natural forest swamps and its influence mechanism . The results showed that all three types of forest swamps before harvesting were methane (-0.19 ~ -1.85mgm-2d-1), and both deforestation and clear-cutting resulted in the decrease of three types of forest swamps as atmospheric methane sinks (- 0.22 ~ -1.29mgm-2d-1) or from the reversion of atmospheric methane to the source of methane (0.50-157.37mgm-2d-1). The combined effects of temperature and water level lead to changes in the methane fluxes of forest swamps after harvesting. In order to reduce the emission of methane gas, when it is necessary to utilize the tree resources of forest swamps, the harvesting method should try its best to avoid clear cutting and only carry out proper selective cutting.