Abstract: Understanding carbon storage and its spatial distribution characteristics of public welfare forest at the regional scale and estimating the carbon sequestration capacity of dominant tree species (groups) can provide reference for policymaking of ecosystem conservation. Baishanzu National Park preserves the most typical and integrated midsubtropical forest ecosystem in the southeast coast of China. The carbon density and carbon storage characteristics, however, areunknown. The carbon density, carbon storage and its spatial distribution at different regions were evaluated by using compatibility biomass model and carbon conversion coefficient suitable for the dominated tree species (groups) based on continuous forest inventory data involved in the public welfare forests in Baishanzu National Park. The results showed that the average carbon density in tree layer of the public welfare forests was 58.12 t·hm^-2 and carbon storage was 2088250.4 t. The carbon density of Pinus taiwanensis forest, mixed broadleaved forest, and mixed coniferous and broadleaved forest was 65.36, 60.64, and 67.27 t·hm^-2, while the carbon density of softwood forest and Phyllostachys edulis forest was 29.23 and 16.12 t·hm^-2, respectively. The proportions of carbon storage at the different age groups of young, middle-aged, pre-mature, mature, and over-mature forests to total carbon storage were 17.42%, 16.10%, 19.41%, 39.10% and 7.97%, respectively. Among different regions in Baishanzu National Park, carbon density at Qingyuan County was 62.16 t·hm^-2, which was 7.02% and 125.87% higher than that of Longquan City and Jingning County, respectively. Furthermore, the higher carbon density was mainly distributed in the north, middle, and southwest region, while the lower carbon density was distributed in the east region. The young and middle-aged forests accounted for 33.52% of total carbon storage. Therefore, we should strengthen the tending of young and middle-aged forests to improve carbon sequestration capacity of forests during ecosystem conservation.

Key words: carbon storage, public welfare forest, dominant tree species (group), carbon density, spatial distribution.