Hu Yanqiu, Su Zhiyao, Li Wenbin, Li Jingpeng, Ke Xiandong
College of Forestry, South China Agricultural University, Guangzhou, Guangdong Province, China.
PLoS One. 2015 Aug 28;10(8):e0136984. doi: 10.1371/journal.pone.0136984. eCollection 2015.
We assessed the impact of species composition and stand structure on the spatial variation of forest carbon density using data collected from a 4-ha plot in a subtropical forest in southern China. We found that 1) forest biomass carbon density significantly differed among communities, reflecting a significant effect of community structure and species composition on carbon accumulation; 2) soil organic carbon density increased whereas stand biomass carbon density decreased across communities, indicating that different mechanisms might account for the accumulation of stand biomass carbon and soil organic carbon in the subtropical forest; and 3) a small number of tree individuals of the medium- and large-diameter class contributed predominantly to biomass carbon accumulation in the community, whereas a large number of seedlings and saplings were responsible for a small proportion of the total forest carbon stock. These findings demonstrate that both biomass carbon and soil carbon density in the subtropical forest are sensitive to species composition and community structure, and that heterogeneity in species composition and stand structure should be taken into account to ensure accurate forest carbon accounting.
我们利用在中国南方亚热带森林中一块4公顷样地收集的数据，评估了物种组成和林分结构对森林碳密度空间变异的影响。我们发现：1）不同群落间森林生物量碳密度存在显著差异，这反映出群落结构和物种组成对碳积累有显著影响；2）不同群落中土壤有机碳密度增加而林分生物量碳密度降低，这表明亚热带森林中林分生物量碳和土壤有机碳的积累可能由不同机制所致；3）中、大径级的少数树木个体对群落生物量碳积累贡献最大，而大量幼苗和幼树对森林总碳储量的贡献比例较小。这些发现表明，亚热带森林中的生物量碳和土壤碳密度均对物种组成和群落结构敏感，为确保准确的森林碳核算，应考虑物种组成和林分结构的异质性。
