[Forest carbon rates at different scales in Northeast China forest area]

To accurately estimate forest carbon storage is of significance in researching terrestrial ecosystem carbon cycle and global change. Based on the survey data from the representative plots in Northeast China forest area (Da Xing' an Mountains, Xiao Xing' an Mountains, Zhangguangcai Mountains and Changbai Mountains) in 2007 and 2008 and the inventory data in the same period, and by using the models for estimating ground tree biomass, shrub biomass, and grass biomass and the Multi N/C 3000 for measuring forest carbon rate in laboratory, this paper calculated the forest biomass and carbon storage in the forest area, and analyzed the variation and stability of the forest carbon rates at different scales. There was an obvious difference in the carbon rates among tree organs, being the highest in leaf (0.4448), followed by in branch (0.4422), bark (0.4398), and trunk (0.4351). In Changbai and Zhangguangcai Mountains, coniferous forest had a higher carbon rate than broad-leaved forest; whereas in Daxing' an and Xiaoxing' an mountains, it was in adverse. In Northeast China forest area, the forest carbon rates were relatively stable, with a total value of 0.44.