PS 23-36 - Annual carbon accumulation of Prunus serrulata, Ginkgo biloba, and Zelkova serrata in settlements, Korea

Background/Question/Methods

Settlements are the type of land-use categories that include street trees, urban parks, and house gardens. Despite much attention being paid to carbon sequestration in settlements, there is a lack of research on carbon sequestration in trees of settlements. This study aims to estimate annual carbon accumulation per tree of Prunus serrulata, Ginkgo biloba, and Zelkova serrata by calculating annual diameter at breast height (DBH) growth rates and developing DBH-based allometric equations. Annual DBH growth rates were calculated based on the linear regression between DBH and tree age. Allometric equations were developed by destructively analyzing 20, 15, and 19 trees of P. serrulata, G. biloba, and Z. serrata and non-destructively analyzing 101, 106, and 62 trees of P. serrulata, G. biloba, and Z. serrata, respectively. For non-destructive analyses, tree volume was calculated based on the diameters by height which were remotely collected using a laser dendrometer. Eventually, annual carbon accumulation per tree was estimated as the difference of carbon stocks between year t and year t + 1, based on the annual DBH growth rates and allometric equations.

Results/Conclusions

Annual DBH growth rates (cm yr^-1) between age 0 to 30 years were highest in Z. serrata (0.8409) and lowest in G. biloba (0.5558). The allometric equations of P. serrulata, G. biloba, and Z. serrata were Y=0.154DBH^2.100, Y=0.084DBH^2.303, and Y=0.451DBH^1.905, respectively. All of the allometric equations developed were statistically significant (p< 0.05), and the coefficient of determination (R²) was 0.891-0.935. Annual carbon accumulation per tree (kg C yr^-1) of P. serrulata, G. biloba, and Z. serrata was 3.29, 2.71 and 5.54 at DBH 20 cm, and 5.10, 4.57, and 7.94 at DBH 30 cm, respectively. Overall, these results are lower than the default value of temperate zones in IPCC guideline, however, they are within the range of the default value of all ecological zones. The current study attributes to understanding the growth and carbon accumulation of trees in settlements. Considering that various species are being planted in settlements, additional studies on annual growth rates and allometric equations for commonly distributed tree species in settlements are needed, which enables accurate estimation of annual carbon accumulation in settlements.