Carbon emission characteristics of branch and leaf combustion of typical tree species in different forest regions of China

  Objective  The combustion of forest fuel releases a large amount of carbon containing gas and particles, which dramatically impacts the atmospheric environment and the global carbon cycle.

  Method  In this study, a self-designed biomass combustion system was used to simulate the branch and leaf combustion of 19 typical tree species in northeastern, southern and southwestern forest regions of China. The differences of emission factors among carbon gas (CO₂, CO and C_xH_y), particulate matter (PM_2.5) and carbon component (elemental carbon, EC and organic carbon, OC) in particulate matter were analyzed comparatively between different tree species, different tree types and varied forest regions.

  Result  (1) Pinus massoniana had the highest emission factors of CO₂, CO, EC, OC and PM_2.5, which were (1 588.00 ± 104.43) g/kg, (324.80 ± 11.60) g/kg, (28.45 ± 4.12) g/kg, (3.42 ± 0.58) g/kg and (12.03 ± 1.46) g/kg, respectively. The emission factors of branches and leaves among tree species showed a significant difference. (2) The emission factors of carbon-containing matter from coniferous trees in different forest areas were generally higher than that of broadleaved trees, and carbon emission factor ratio of coniferous trees was higher than that of broadleaved trees. (3) Additionally, the average emission factors of tree species varied in different forest regions, and the southern forest region had the highest emission factors of CO₂ (1 344.49 ± 61.18) g/kg, CO (259.40 ± 14.54) g/kg, EC (2.18 ± 0.41) g/kg, and OC (7.96 ± 0.98) g/kg, respectively.

  Conclusion  Our study reveals the carbon emission characteristics of typical tree species in different forest regions of China, which is conducive to the accurate research on the effect of forest fires on regional carbon circulation and large-scale carbon emission estimation.