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热带森林是碳净来源

A Baccini¹, W Walker², L Carvalho³

¹The Woods Hole Research Center, 149 Woods Hole Road, Falmouth, MA 04523, USA. abaccini@whrc.org.

Science (New York, N.Y.)

|October 4, 2017

概括

热带森林是一个重要的碳净来源,每年释放425.2 Tg C. 这与之前的估计相反, 凸显了森林砍伐和退化对全球碳平衡的影响.

科学领域:

生态学
环境科学
遥感技术

背景情况:

热带生态系统的碳平衡是有争议的,大气研究表明了沉和生态研究表明了来源.
准确量化热带森林的碳动态对于了解全球气候变化至关重要.

研究的目的:

量化热带木质生长植物地表碳密度的年度净变化.
提供热带森林净碳交换的直接,基于测量的证据.

主要方法:

使用了12年的MODIS (中等分辨率成像光谱辐射仪) 热带卫星数据.
热带木质生态的地面碳密度的量化年净变化.

主要成果:

热带森林是一个净碳来源,每年释放425.2 ± 92.0 千克的碳 (Tg C年−1).
年度碳损失为861.7±80.2 Tg C 年−1,而增益为436.5±31.0 Tg C 年−1.
森林退化和破坏占总碳损失的68.9%.

结论:

直接的卫星测量证实热带森林是大气碳的净来源.
森林砍伐和退化是热带森林碳排放的主要驱动因素,影响全球碳预算.

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