China's ecological rehabilitation: Unprecedented efforts, dramatic impacts, and requisite policies

The location and mechanisms responsible for the carbon sink in northern mid-latitude lands are uncertain. Here, we used an improved estimation method of forest biomass and a 50-year national forest resource inventory in China to estimate changes in the storage of living biomass between 1949 and 1998. Our results suggest that Chinese forests released about 0.68 petagram of carbon between 1949 and 1980, for an annual emission rate of 0.022 petagram of carbon. Carbon storage increased significantly after the late 1970s from 4.38 to 4.75 petagram of carbon by 1998, for a mean accumulation rate of 0.021 petagram of carbon per year, mainly due to forest expansion and regrowth. Since the mid-1970s, planted forests (afforestation and reforestation) have sequestered 0.45 petagram of carbon, and their average carbon density increased from 15.3 to 31.1 megagrams per hectare, while natural forests have lost an additional 0.14 petagram of carbon, suggesting that carbon sequestration through forest management practices addressed in the Kyoto Protocol could help offset industrial carbon dioxide emissions.

The giant panda has been restricted to several disjunct montane forest populations, and habitat loss and fragmentation are the primary threats to its survival. For pandas to survive, conservation efforts must focus on larger landscapes rather than individual nature reserves. China recently initiated several policies, including the Natural Forest Conservation Program and Grain-to-Green Policy, which provide a historic opportunity to integrate panda conservation into national policies. Simultaneously, China is promoting the Western China Development Program, which calls for substantial infrastructure and hydropower development and economic investments. Integrating panda conservation into these development policies will be a critical challenge.