Component specific carbon content and storage of Cinnamomum camphora in Guangdong Province

Abstract

To quickly and accurately measure the car on sink in forest carbon sequestration projects and to monitor carbon storage changes in forest vegetation of Guangdong Province, Cinnamomum camphora trees were selected as the object to establish a carbon storage model. Based on the 8th continuous forest inventory data for C. camphora distribution in Guangdong Province in 2012, all 90 sample trees were classified in 10 diameter classes according to 2, 4, 6, 8, 12, 16, 20, 26, 32, and 38 cm. The weighted mean and total carbon storage were calculated for individual trees of C. camphora including components of stem wood, bark, leaves, branches, and roots among different diameter levels by using the analysis of variance (ANOVA) method. Results showed that:(1) The average carbon rate of C. camphora in Guangdong was 0.509 6. There were no significant differences among stems, leaves, branches, and roots (P>0.05) for the average carbon content in DBH levels, but the carbon content of bark was significantly lower than other components (P branch > root > bark > leaf. (5) With an increase in DBH, the ratio of stem carbon storage increased first and then decreased, the proportion of bark carbon reserves was stable at an early age but decreased in later stages, the proportion of leaves and roots changed little, and the carbon storage of branches was stable first and increased in a later period at a significant level of 0.05. (6) The optimal carbon storage(Ct) model of C. camphora and R2 for age (A) was Ct=0.019 4A2.652 0, R2=0.602 9; for DBH was Ct=0.011 8D2.937 6, R2=0.943 2; and for D2H was Ct=0.001 6(D2H)1.268 6, R2=0.910 5. Through cross validation, the model fitting effect was significant (P < 0.01). The fitting carbon storage model of C. camphora with D and D2H was better than the age vatiable. In the model application, the model with D and D2H should be selected to estimate the carbon storage. When the diameter (D) and D2H were not easy to be measured but the age was easy to know, the age could be used to estimate the carbon storage.