Abstract: The dynamic change of carbon storage,carbon density and the value of carbon fixation and oxygen release by forest ecosystem were studied in Guangxi Zhuang Autonomous Region in order to provide the reference basis for the forest scientific management based on forest inventory data.The carbon storage and carbon density of forest in Guangxi Zhuang Autonomous Region were assessed by the regression between forest volume and stand biomass of different forest types.The total productivity and the carbon fixation and oxygen release value were estimated by the regression between stand biomass and net production of each forest type.The total forest carbon storage of Guangxi had a rising trend overall in recent 10 years.The total forest carbon increased to 33 715 million tons from 19 718 million tons from 2 000 to 2 010,the annual average growth was 7.1%.Three annual average carbon densities were 26.38,34.92 and 37.29 tons per hectare in 2000,2005 and 2010.An increase trend was showed from 2000 to 2010.The broad-leaved forest had a larger contribution to total forest carbon storage among different forest types,accounted for 68.66%,68.19% and 67.82% of the annual total carbon storage in 2000,2005 and 2010.The proportion of natural forest carbon storage was decreasing while the plantations carbon storage increased with annual average growth of 12.0% during this period.Both the total forest productivity and the carbon fixation and oxygen release value were increased in Guangxi,the total productivity was 6 887,7 554 and 8 190 million tons in 2000,2005 and 2010.The total value of carbon fixation and oxygen release were 133.148,146.049,and 158.344 billion Yuan respectively.

Key words: forest volume, stand biomass, carbon storage, carbon density, Guangxi