Abstract: Trunk plays an important role in mediating methane emissions and respiration in the mangrove wetlands. To better understand the pattern and control of greenhouse gas effluxes in mangrove wetlands, the methane transport rates and respiration rates were measured in the trunk of Kandelia obovata in Zhangjiang River Estuary, southeast China. Using closed static chambers, our results showed that the trunk methane transport rates were significantly higher in the middle intertidal zone ((91.19±16.63)μg/(m²·h)) and high intertidal zone ((0.71±0.24)μg/(m²·h)) (P < 0.001). By contrast, the respiration rates were comparable between the two intertidal zones. The methane transport rates of trunk were in accordance with the soil moisture, while the concentration of dissolved methane was positively and negatively correlated with pore water c(CH₄) and ρ(DON), respectively. The trunk respiration rates of Kandelia obovata were determined by DBH (diameter at breast height), while the rates of trunk methane transport were not affected by DBH. The traits of plant growth had more pronounced influence on trunk respiration rates compared to the spatial heterogeneity of mangrove wetlands, and vice versa on the trunk methane transport rates.