Biomass carbon storage and its sequestration potential of afforestation under natural forest protection program in China
Since 1998, the Natural Forest Protection (NFP) program has been carried out to address the deterioration of ecological environment of China. By reclassifying natural forests of the country, adjusting the goal of the forest management and promoting the natural forest resource protection, cultivation and development,the program aims to sustain and improve the ecological environment while meeting the economic and social demands for forest products.
The NFP program has significantly contributed to improving the ecological environment in China as well as the carbon sequestration capacity of terrestrial ecosystems (Hu and Liu, 2006).However, there have been few precise estimates of the carbon storage and carbon sequestration potential of plantation forest established under the NFP program. The objectives of this study were: 1) to estimate the carbon storage of the planted forests under the NFP program at the end of the first stage of the program (1998–2010); and 2) to estimate the carbon sequestration potential of forests planted in the preceding stage at the end of second stage (2011–2020).
Methods and Results
Based on the data from China's Seventh Forest Inventory for the period of 2004-2008, area and stand volume of different types and age-classes of plantation were used to establish the relationship between biomass density and age of planted forests in different regions of the country. this study calculated the biomass carbon storage of the afforestation in the first-stage of the program.On this basis, the carbon sequestration potential of these forests was estimated for the second stage of the program (2011-2020). Biomass carbon storage of plantation established in the first stage of the program was 33.67 Tg C, which was majority accounted by protection forests (30.26 Tg C). There was a significant difference among carbon storage in different regions, which depended on the relationship of biomass carbon density, forest age and plantation area. Under the natural growth, the carbon storage was forecasted to increase annually from 2011 to 2020, reaching 96.03 Tg C at the end of the second-stage of the program in 2020. The annual growth of the carbon storage was forecasted to be 6.24 Tg C/yr.
The objectives of the NFP program are to protect the natural forest, construct the public welfare forest, and achieve the sustainable development of forest. Afforestation under the NFP program not only improves the ecological environment of China, but also has a greater potential for the carbon storage in China's forests. So afforestation has been an important component of the NFP program.