Scholarlink

<p>The burial of organic matter in marine environments is considered the dominant long-term source of atmospheric oxygen, yet the contribution of terrestrial burial remains poorly constrained. Quantifying any oxygen surplus associated with organic matter burial conventionally assumes a 1:1 oxygen-to-carbon stoichiometry. Here we aim to test this assumption and quantify net oxygen release from a terrestrial setting over time. We applied direct redox titration to a 10,600-year Congo Basin peat core, a hotspot of carbon accumulation. We find systematic deviation from the 1:1 ratio, enabling precise, time-resolved quantification of the net redox imbalance. Fluxes were strikingly nonlinear: drier phases triggered abrupt ~80% declines in net oxygen surplus within centuries, followed by rapid recovery when wetter conditions returned, revealing a hydroclimate-sensitive carbon–oxygen valve. Cumulative Holocene oxygen surplus reached 83 [68–100] petagrams of oxygen equivalents. Using the Congo oxygen-to-carbon ratio, we estimate that global peatland net oxygen production is commensurate with continental weathering oxygen sinks in the Holocene—a flux comparable in magnitude to marine burial but responding on orders-of-magnitude-shorter timescales. This finding provides qualitative insight into the contribution of terrestrial environments to Earth’s redox balance. It also offers a direct stoichiometric framework—applicable to coal archives—for quantifying that contribution across the Phanerozoic, independent of isotopic proxies, complementing existing marine-based models.</p>

错误：搜索内容不能为空，请输入英文关键词
错误：关键词超出字数限制，请精简
高级检索

Hydroclimate controls Congo peatland net oxygen release over the past 10,600 years

  • 期刊论文

  • 出版模式：

    开放获取

  • 发表日期：

    2026年7月10日

查看全文
  • M. E. Galvez,
  • S. Wu,
  • Y. Garcin,
  • E. Schefuß,
  • G. Gassier,
  • J. Lebamba,
  • C. K. Kiahtipes,
  • F. Bokomba Bwamangele,
  • R. Kidebua Lutonadio,
  • H.-P. Wotzka,
  • T. Adatte,
  • S. L. Jaccard

摘要

The burial of organic matter in marine environments is considered the dominant long-term source of atmospheric oxygen, yet the contribution of terrestrial burial remains poorly constrained. Quantifying any oxygen surplus associated with organic matter burial conventionally assumes a 1:1 oxygen-to-carbon stoichiometry. Here we aim to test this assumption and quantify net oxygen release from a terrestrial setting over time. We applied direct redox titration to a 10,600-year Congo Basin peat core, a hotspot of carbon accumulation. We find systematic deviation from the 1:1 ratio, enabling precise, time-resolved quantification of the net redox imbalance. Fluxes were strikingly nonlinear: drier phases triggered abrupt ~80% declines in net oxygen surplus within centuries, followed by rapid recovery when wetter conditions returned, revealing a hydroclimate-sensitive carbon–oxygen valve. Cumulative Holocene oxygen surplus reached 83 [68–100] petagrams of oxygen equivalents. Using the Congo oxygen-to-carbon ratio, we estimate that global peatland net oxygen production is commensurate with continental weathering oxygen sinks in the Holocene—a flux comparable in magnitude to marine burial but responding on orders-of-magnitude-shorter timescales. This finding provides qualitative insight into the contribution of terrestrial environments to Earth’s redox balance. It also offers a direct stoichiometric framework—applicable to coal archives—for quantifying that contribution across the Phanerozoic, independent of isotopic proxies, complementing existing marine-based models.