Tropical peat swamp forest is a unique ecosystem rich in carbon and water, accumulating a huge amount of carbon as peat. However, the huge carbon pool has been threatened by oxidative peat decomposition and fire loss mainly because of deforestation and drainage. Fire causes acute carbon dioxide (CO₂) emissions through the combustion of biomass and peat. Also, fire should change the CO₂ balance of postfire ecosystems. Although it is crucial to quantify CO₂ balance even after a fire event to understand the total fire impact, information based on field measurement is lacking. Thus, we had measured eddy CO₂ flux above a repeatedly burned degraded peat forest for about 13 years since 2004. The site was a stable CO₂ source of 147−290 g C m⁻² yr⁻¹ for five years after a stand-replacing fire in 2002. Unexpectedly, a moderate-severity fire in 2009 changed the site to a CO₂ sink of about −600 g C m⁻² yr⁻¹. The drastic change would have been caused by a large decrease in the decomposition of plant debris, which had accumulated since the 2002 fire but was burned by the 2009 fire. In contrast, gross primary production (GPP) remained about the same even though vegetation was damaged, mainly because year-round wet conditions caused by a La Niña event promoted the regrowth of hygrophilous herbaceous plants and were favorable to their GPP. The site also had a low-severity fire and was drained in 2014 but did not return to a CO₂ source. However, the net ecosystem CO₂ uptake after the 2009 fire was insufficient to recover a large amount of fire CO₂ emission. If CO₂ emissions from four fires in 1999, 2002, 2009 and 2014 are counted, the site is expected to owe an outstanding CO₂ debt of 25 kg C m⁻².

热带泥炭沼泽森林是一个独特的生态系统，富含碳和水，会积聚大量的碳作为泥炭。然而，巨大的碳库受到氧化泥炭分解和失火的威胁，这主要是由于森林砍伐和排水造成的。火灾会通过生物质和泥炭的燃烧而导致严重的二氧化碳（CO ₂）排放。此外，火灾应改变火灾后生态系统的CO ₂平衡。尽管即使在发生火灾后量化CO ₂平衡对于了解整个火灾影响也至关重要，但仍缺乏基于现场测量的信息。因此，自2004年以来，我们已经测量了经过反复燃烧的退化泥炭森林上方约13年的涡流CO ₂流量。该地点是稳定的CO ₂在2002年替换林火后的147-290 g C m ^-2 yr ^-1排放源持续了5年。出乎意料的是，2009年的中度大火将场地变成了约-600 g C m ^- ₂的CO ₂汇。²年^-1。剧烈的变化可能是由于植物残渣的分解大幅度减少所致，这种分解自2002年大火以来积累了下来，但被2009年大火焚毁了。相比之下，即使植被受到破坏，初级生产总值（GPP）仍保持不变，这主要是由于拉尼娜事件引起的全年湿润条件促进了亲水性草本植物的生长并对其GPP有利。该地点还发生了低烈度大火，并于2014年被排水，但未恢复为原产地证书。_2个来源。但是，2009年大火后生态系统的净CO ₂吸收不足以恢复大量的大火CO ₂排放。如果算上1999年，2002年，2009年和2014年四场大火的CO ₂排放量，则预计该地点将欠下25 kg C m ^-2的未偿还CO ₂债务。