the changes in chinas forests an analysis using the forest identity中国森林的变化分析使用森林的身份.pdf

The Changes in China’s Forests: An Analysis Using the Forest Identity Lei Shi, Shuqing Zhao, Zhiyao Tang, Jingyun Fang* College of Urban and Environmental Sciences, and Key Laboratory for Earth Surface Processes of the Ministry of Education, Peking University, Beijing, China Abstract Changes in forest carbon stocks are a determinant of the regional carbon budget. In the past several decades, China has experienced a pronounced increase in forest area and density. However, few comprehensive analyses have been conducted. In this study, we employed the Forest Identity concept to evaluate the changing status of China’s forests over the past three decades, using national forest inventory data of five periods (1977–1981, 1984–1988, 1989–1993, 1994–1998, and 1999– 2003). The results showed that forest area and growing stock density increased by 0.51% and 0.44% annually over the past three decades, while the conversion ratio of forest biomass to growing stock declined by 0.10% annually. These developments resulted in a net annual increase of 0.85% in forest carbon sequestration, which is equivalent to a net biomass carbon uptake of 43.8 Tg per year (1 Tg = 1012 g). This increase can be attributed to the national reforestation/ afforestation programs, environmentally enhanced forest growth and economic development as indicated by the average gross domestic product. Citation: Shi L, Zhao S, Tang Z, Fang J (2011) The Changes in China’s Forests: An Analysis Using the Forest Identity. PLoS ONE 6(6): e20778. doi:10.1371/ journal.pone.0020778 Editor: Jon Moen, Umea University, Sweden Received January 26, 2011; Accepted May 11, 2011; Published June 9, 2011 Copyright: 2011 Shi et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrest