Abstract:By using process model Sim-CYCLE based on dry matter production theory, this pa per estimated the gross primary productivity (GPP), net primary productivity (NP P), net ecosystem productivity (NEP), ecosystem carbon storage (WE), total plant carbon storage (WP), and total soil carbon storage (WS) of broad-leave d Korean pine forest ecosystem in Changbai Mountains from 1982 to 2003, and anal yzed the variations of these indices under present climate condition and carbon equilibrium state as well as the responses of these indices to climate change sc enarios in the future. Under present climate condition, the estimated GPP, NPP, and NEP were 149, 87, and 27 Mg C·hm-2·a-1, being 28 Mg C ·hm-2·a-1 less and 14 and 02 Mg C·hm-2·a-1 highe r than the measured values, respectively. The NEP in June〖KG-*3〗-〖KG-*7〗August occupied more than 90% of the annual NEP, and the maximum monthly NEP appeared in July (123 Mg C·hm-2·month-1). The estimated WE, WP, and WS were 5508, 183 8, and 3670 Mg C·hm-2, respectively, very close to the me asured values. From present climate condition to carbon equilibrium state, the e stimated carbon storages of the forest ecosystem increased to some extent, with the GPP and NPP being 177 and 73 Mg C·hm-2·a-1, respectively, suggesting that the role of the forest ecosystem as a carbon “sink” declined g radually with the increase of carbon storage. A 2 ℃-increment of air temperat ure did not benefit the increase of GPP, NPP and NEP, while doubling CO2 conce ntration was in adverse. The effects of the combination of doubling CO2 concen tration and 2 ℃-increment of air temperature on the GPP, NPP, and NEP were si milar to those of doubling CO2 concentration. The climate change scenario in t he future had the same effects both on the carbon storage and on the productivit y of the forest ecosystem, which was mainly correlated to the effects of primary productivity on the carbon storage.