过去的永久土碳大量流失,但现在的土壤净积累
Amelie Lindgren1,2, Gustaf Hugelius3,4, Peter Kuhry3,4
1Department of Physical Geography, Stockholm University, Stockholm, Sweden. amelie.lindgren@natgeo.su.se.
Nature
|August 3, 2018
概括
永久土的碳储量在最后的冰川最大期 (LGM) 时比现在小. 自从LGM以来,土壤碳的显著增加表明永久土并没有导致大气碳的增加.
科学领域:
- 古气候学
- 生物地质化学
- 永久土科学
背景情况:
- 大气中的二氧化碳从最后的冰川最大值 (LGM) 增加到工业化前.
- 永久土的融化和分解可能影响了二氧化碳和甲的转移.
- 脱冰过程中的不稳定的大气同位素信号可能与LGM陆地碳库存有关.
研究的目的:
- 用经验来估计LGM永久土的碳储存.
- 重建LGM生物群的范围和碳含量.
- 评估自LGM以来永久土对大气的净贡献
主要方法:
- 重建LGM生物群的范围.
- 在LGM永久土,泥炭地和沉积物中估计碳含量.
- 北方永久土地区的LGM和当今土壤碳库存的比较.
主要成果:
- 北方永久土地区的LGM土壤碳储量比今天的储量小.
- 随着永久土面积的减少,土壤总碳增加了约400倍.
- 永久土的碳储量可能减少1000倍.
结论:
- 自从LGM发生以来,永久土的碳可能没有对大气中的碳产生任何净贡献.
- 碳储存已经从LGM永久土矿床转移到今天更均的分布.
- 这些结果支持先前关于冰川后永久土碳库存减少的研究.
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