全球森林日益受到土地利用变化、分散化、管理目标变化和退化的影响.运用管理强度描述全球森林动态变化趋势,并概述了与森林管理相关的全球碳库变化.讨论了对"管理"的不同解释,并强调了一些重要的核算和分析问题.全球森林面积自1990年以来下降了3％,但全球各地人工林面积都有所增加,截止2010年已占全球森林面积的近7％.由于人为因素造成的栖息地破碎和退化,使得占所有林地34％的原始森林面积正在下降,尤其是南美洲和非洲.同时,自然再生林面积也有所下降.由于管理强度的增加,1990年以来,非施业林面积(通常被定义为缺乏人类管理计划或保护状态的土地)大幅度下降,截止2010年仅占全球森林的21％,而用于水土保持、生物多样性保护和提供生态系统服务等非木质林产品用地面积大幅增加.从全球来看,木材生产自1990年以来一直相对稳定,但非木质林产品用地面积越来越多,表明林业采伐面积占森林总面积的比例较小.根据管理森林和区域研究领域的发展趋势可知,历史上和现在的森林管理是当前碳储量的一个非常重要的决定因素.目前,已建成的森林抵消了来自使用化石燃料释放二氧化碳的约30％,而减少森林的砍伐可能会将陆地碳地面总吸收量从大约4.0 t升至每年6.2 t.然而,研究结果表明,多样化使用森林土地可能对维持或提高目前的陆地碳汇有重大影响.未来,诸如大气二氧化碳的增加和气候变化等间接的人类影响,以及土地管理的直接影响和木材生物燃料的日益增长的需求,都将成为影响土地管理战略规划和森林生态系统全球碳循环的重要因素.%Global forests are increasingly affected by changes in land use, decentralization, changes in management objectives and degradation. This paper describes trends in global forest area through management intensity and outlines global carbon stock changes associated with forest management. Discussed the different interpretations of management and highlighted some important accounting and analysis issues. The global forest area has fallen by 3 per cent since 1990. As of 2010, the area of planted forests has increased worldwide and now accounts for nearly 7 per cent of the global forest area. The habitat fragmentation and degradation caused by human factors have resulted in a 34 per cent reduction in the virgin forest area of all forest land, especially in South America and Africa. At the same time, the area of natural regeneration forest has also declined. As a result of the increase in management intensity, non-operating forest area (usually defined as a lack of human management plan or protected land) has declined significantly since 1990, only 21％ of the global forest, and for soil and water conservation, biodiversity protection and provision of ecosystem services such as non-timber forest product land area increased significantly. Globally, timber production has been relatively stable since 1990, but the area of non-timber forest products is increasing, indicating that the area of forest logging is smaller than the total forest area. Based on trends in the management of forests and regional research, it is clear that historical and current forest management is a very important determinant of current carbon stocks. At present, the completed forest has offset about 30％ of the global CO2 emissions from fossil fuels, while reducing deforestation may reduce the total terrestrial carbon footprint from about 4.0 to 6.2 tonnes per year. However, our findings suggest that diversification of the use of forest land may have a significant impact on maintaining or enhancing the current terrestrial carbon sinks. In the future, indirect human impacts such as increased atmospheric carbon dioxide and climate change, as well as the direct impact of land management and the growing demand for wood biofuels, will become increasingly influential in land management strategies and the role of forests in the global carbon cycle.
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