The carbon cycle includes important fluxes of methane (CH₄) and carbon dioxide (CO₂) between the ecosystem and the atmosphere. The fluxes may acquire either positive (release) or negative values (consumption). We calculated these fluxes based on short-campaign in situ chamber measurements from four ecosystems of South Vietnam: intact mountain rain forest, rice field, Melaleuca forest and mangroves (different sites with Avicennia or Rhizophora and a typhoon-disturbed gap). Soil measurements were supplemented by chamber measurements of gas fluxes from the tree stems. Measuring CH₄ and CO₂ together facilitates the assessment of the ratio between these two gases in connection with current conditions and specificity of individual ecosystems. The highest fluxes of CH₄ were recorded in the Melaleuca forest, being within the range from 356.7 to 784.2 mg CH₄–C m⁻² day⁻¹ accompanied by higher fluxes of CH₄ release from Melaleuca tree stems (8.0–262.1 mg CH₄–C m⁻² day⁻¹). Significant negative soil fluxes of CH₄ were recorded in the mountain rain forest, within the range from − 0.3 to − 0.8 mg CH₄–C m⁻² day⁻¹. Fluxes of CO₂ indicate prevailing aerobic activity in the soils of the ecosystems investigated. Quite a large variability of CO₂ fluxes was recorded in the soil of the Avicennia mangroves. The in situ measurements of different ecosystems are fundamental for follow-up measurements at different levels such as aerial and satellite gas fluxes observations.

碳循环包括生态系统与大气之间的重要甲烷（CH ₄）和二氧化碳（CO ₂）通量。通量可以获取正值（释放）或负值（消耗）。我们基于来自越南南部四个生态系统的短时运动原位腔室测量值计算了这些通量：完整的山区雨林，稻田，千层林和红树林（不同的地点有紫花苜蓿或根茎和受台风干扰的间隙）。对土壤测量结果的补充是对来自树干的气体通量进行室测量。测量CH ₄和CO ₂共同促进了结合当前条件和单个生态系统的特异性评估这两种气体之间的比率。在千层林中记录到最高的CH ₄通量，范围为356.7至784.2 mg CH ₄ –C m ^-2 day ^-1，同时从千层树茎中释放出更高的CH ₄通量（8.0–262.1 mg CH ₄ –C m ^-2天^-1）。在山区雨林中记录到CH _4的显着负土壤通量，范围为-0.3至-0.8 mg CH ₄ -C m ^-2第^-1天。CO _2的通量表明在所调查的生态系统的土壤中普遍存在有氧活动。在Avicennia红树林的土壤中记录到的CO ₂通量变化很大。不同生态系统的原位测量对于不同水平的后续测量（例如，空中和卫星气体通量观测）至关重要。