世界森林的碳汇
Yude Pan1, Richard A Birdsey2, Oliver L Phillips3
1USDA Forest Service, Durham, NH, USA. yude.pan@usda.gov.
Nature
|July 17, 2024
概括
全球森林保持稳定的碳汇,吸收大量的二氧化碳. 然而,区域变化发生,温带和热带再生森林增加了沉降能力,而北极和完整的热带森林由于干扰和面积减少而出现下降.
科学领域:
- 生态与气候科学
- 森林碳封存
- 大陆生态系统
背景情况:
- 陆地生态系统,特别是森林,通过吸收大气中的二氧化碳 (CO2) 在缓解气候变化方面发挥着至关重要的作用.
- 了解森林碳汇的长期趋势和生物群特异性贡献对于气候建模和政策制定至关重要.
研究的目的:
- 在全球生物群中对陆地二氧化碳吸收的森林贡献进行地面长期评估.
- 分析森林三十年来碳汇的生物层面变化.
- 评估森林碳汇相对于化石燃料排放和森林砍伐的影响.
主要方法:
- 从北极,温带和热带生物群的30年实地森林数据的综合.
- 分析全球和生物层面的碳汇趋势.
- 森林碳吸收能力与化石燃料排放和森林砍伐率的比较.
主要成果:
- 从20世纪90年代到2010年代,全球森林碳汇保持稳定. 3.5 3.6 Pg C yr-1 的时间.
- 由于森林面积的扩大,温带和热带再生森林的碳吸收增加了 (分别为30%和29%).
- 由于干扰加剧和面积减少,北极和完整的热带森林的碳吸收减少了 (分别为-36%和-31%).
结论:
- 虽然全球森林的碳吸收稳定,但由于土地面积的变化和干扰制度存在显著的区域差异.
- 全球森林消耗将近一半的化石燃料排放量, 但热带森林砍伐损失了三分之二.
- 森林老化,持续的森林砍伐和干扰的增加可能会威胁到未来的森林沉降能力,需要有针对性的土地管理政策.
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