The main pathways of CH₄ exchange between air and water are molecular diffusion and ebullition. However, the relative contribution of these two pathways to total methane emissions and their environmental controls are far from clear. In this paper, by using float static chamber and diffusion model, we measured the CH₄ total emission flux (F_total), diffusion flux (F_diff) and ebullitive flux (F_ebul) in three types of habitats (mudflat, Carex meadow and reed land) in Lake Dongting wetlands during flooding period. Further, the environmental controls on CH₄ flux were analyzed through stepwise regression and linear regression model. The results showed that total CH₄ emission flux was the highest in Carex meadow (6.49±3.12 mg (C)/(m²·h)) among three habitat types. The CH₄ diffusion fluxes accounts for 1.34% to 3.91% to total CH₄ emissions in the three sites, while the ebullitive flux contributed 96.09% to 98.66% to total CH₄ emissions. The stepwise regression analysis between CH₄ emission and environmental factors showed that CH₄ diffusion flux was affected by water pH, conductivity and water temperature, while the total CH₄ emission flux and CH₄ ebullitive flux were mainly affected by water temperature. Furthermore, we found that water temperature determines the dominant emission pathway:when the water temperature was below 11.7℃, diffusion was the main way for CH₄ emission otherwise ebullition pathway dominant the CH₄ emission. However, whether this temperature threshold is equally applicable to other types of wetlands still requires more experimental verification. This study is important for revealing the mechanism of CH₄ emissions in tropical and subtropical lakes.