[Relationship between surface dead fuel loadings and environmental factors in southern Jiangxi, China]

The distribution pattern of forest fuel loading is driven by the interaction of environmental factors, such as terrain and vegetation. Based on field sampling data of surface dead fuels of seven main forest types in southern Jiangxi Province, and according to the classification standard of different time-lags, we constructed structural equation models to explore the relationship between surface fuel loadings and environmental factors such as terrain and vegetation etc. We analyzed the influence path of each factor and its direct, indirect, and total influence. The results showed that the coniferous and broad-leaved mixed forest had the highest loadings and the Phyllostachys heterocycla pure forest had the lowest loadings for all the 1, 10, and 100 h time-lag fuels. The influencing coefficient of environmental factors for 1 h time-lag fuels were ranked as: slope (0.40) > crown height (0.07) > tree species (-0.03) > canopy closure (0.01). For the 10 h time-lag fuels, the environmental factors were ranked as: diameter at breast height (0.15) >tree species (-0.09) > aspect (-0.08) > canopy closure (-0.06). For the 100 h time-lag fuels, the environmental factors were ranked as: aspect (0.25) > diameter at breast height (0.19) > canopy closure (-0.08) > tree species (0.02). The influencing coefficient of environmental factors for the total fuels were ranked as: slope (0.22) > tree species (-0.04), canopy closure (-0.04) > crown height (-0.01).