2025-03-21 カリフォルニア工科大学 (Caltech)
Though carbon stored in land has been increasing, biomass has remained relatively steady. This is because carbon in land has been mostly stored in nonliving pools like soils and sediments.Credit: Bar-On et al., Science 387, 1291-1295 (2025)
＜関連情報＞
- https://www.caltech.edu/about/news/how-the-planet-stores-our-excess-carbon-emissions
- https://www.science.org/doi/10.1126/science.adk1637
地球全体の陸域炭素蓄積における最近の増加は、ほとんどが非生物プールに蓄積されている Recent gains in global terrestrial carbon stocks are mostly stored in nonliving pools
Yinon M. Bar-On, Xiaojun Li, Michael O’Sullivan, Jean-Pierre Wigneron, […], and Woodward W. Fischer
Science Published:20 Mar 2025
DOI:https://doi.org/10.1126/science.adk1637
Editor’s summary
Approximately 30% of the carbon emitted by human activity has been taken up on land, but exactly how and where that uptake has been achieved has been an open question. Bar-On et al. examined existing observational records of terrestrial carbon pools and found that live biomass has stored only a small fraction of that carbon, the bulk having been incorporated into nonliving organic matter (see the Perspective by Canadell). This work has important implications for understanding how quickly carbon is returned to the atmosphere. —Jesse Smith
Abstract
Terrestrial sequestration of carbon has mitigated ≈30% of anthropogenic carbon emissions. However, its distribution across different pools, live or dead biomass and soil and sedimentary organic carbon, remains uncertain. Analyzing global observational datasets of changes in terrestrial carbon pools, we found that ≈35 ± 14 gigatons of carbon (GtC) have been sequestered on land between 1992 and 2019, whereas live biomass changed by ≈1 ± 7 GtC. Global vegetation models instead imply that sequestration has been mostly in live biomass. We identify key processes not included in most models that can explain this discrepancy. Most terrestrial carbon gains are sequestered as nonliving matter and thus are more persistent than previously appreciated, with a substantial fraction linked to human activities such as river damming, wood harvest, and garbage disposal in landfills.
