College of Urban and Environmental Science, and Key Laboratory for Earth Surface Processes of Ministry of Education, Peking University, Beijing 100871, China.
Sci China Life Sci. 2013 Jul;56(7):661-71. doi: 10.1007/s11427-013-4492-2. Epub 2013 May 31.
Forests play a leading role in regional and global carbon (C) cycles. Detailed assessment of the temporal and spatial changes in C sinks/sources of China's forests is critical to the estimation of the national C budget and can help to constitute sustainable forest management policies for climate change. In this study, we explored the spatio-temporal changes in forest biomass C stocks in China between 1977 and 2008, using six periods of the national forest inventory data. According to the definition of the forest inventory, China's forest was categorized into three groups: forest stand, economic forest, and bamboo forest. We estimated forest biomass C stocks for each inventory period by using continuous biomass expansion factor (BEF) method for forest stands, and the mean biomass density method for economic and bamboo forests. As a result, China's forests have accumulated biomass C (i.e., biomass C sink) of 1896 Tg (1 Tg=10(12) g) during the study period, with 1710, 108 and 78 Tg C in forest stands, and economic and bamboo forests, respectively. Annual forest biomass C sink was 70.2 Tg C a(-1), offsetting 7.8% of the contemporary fossil CO2 emissions in the country. The results also showed that planted forests have functioned as a persistent C sink, sequestrating 818 Tg C and accounting for 47.8% of total C sink in forest stands, and that the old-, mid- and young-aged forests have sequestrated 930, 391 and 388 Tg C from 1977 to 2008. Our results suggest that China's forests have a big potential as biomass C sink in the future because of its large area of planted forests with young-aged growth and low C density.
森林在区域和全球碳（C）循环中发挥着主导作用。详细评估中国森林碳汇/源的时空变化对于估算国家碳预算至关重要，并有助于制定针对气候变化的可持续森林管理政策。在这项研究中，我们利用六期全国森林资源清查数据，探讨了 1977 年至 2008 年间中国森林生物量碳储量的时空变化。根据森林清查的定义，中国的森林分为三组：林分、经济林和竹林。我们使用林分连续生物量扩展因子（BEF）法和经济林及竹林平均生物量密度法，分别估算了每个清查期的森林生物量碳储量。结果表明，研究期间中国森林累计生物量碳（即生物量碳汇）为 1896Tg，其中林分、经济林和竹林分别为 1710、108 和 78Tg。年森林生物量碳汇为 70.2Tg，抵消了同期国内化石 CO2排放的 7.8%。结果还表明，人工林一直是一个持续的碳汇，固碳 818Tg，占林分总碳汇的 47.8%；其中，老龄、中龄和幼龄林分别从 1977 年到 2008 年固碳 930、391 和 388Tg。我们的研究结果表明，由于中国人工林面积大、生长阶段年轻、碳密度低，未来中国森林作为生物量碳汇具有很大潜力。
