Organic Matter Chemistry Drives Carbon Dioxide Production of Peatlands
Organic Matter Chemistry Drives Carbon Dioxide Production of Peatlands
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DOI：
10.1029/2021gl093392
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发表时间：
2021-09
影响因子：
5.2
通讯作者：
A. Normand;B. Turner;L. J. Lamit;Adam N. Smith;B. Baiser;Mark W. Clark;C. Hazlett;Evan S. Kane-
中科院分区：
文献类型：
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作者：
A. Normand;B. Turner;L. J. Lamit;Adam N. Smith;B. Baiser;Mark W. Clark;C. Hazlett;Evan S. Kane-
泥炭地在全球碳（C）循环中发挥着关键作用，占全球土壤中储存的1，500 Pg C的约30%。然而，这个C容易受到气候和土地利用变化的影响。生态系统模型预测扰动对土壤碳库碳通量的影响，但响应可能会显着不同，这取决于土壤有机质（SOM）化学。在这里，我们表明，一个SOM功能组强烈响应环境因素，并预测从泥炭地释放二氧化碳（CO2）的风险。由于温度、土地利用、植被和养分状况的变化，125个泥炭地的SOM分子组成在全球范围内存在显著差异。尽管有这种变化，来自11个地点的子集的泥炭的孵育揭示了O-烷基C（即，碳水化合物）是有氧CO2产生的最强预测因子。这种明确的联系提供了一个简单的参数，可以改善泥炭地CO2通量的模型。
Peatlands play a critical role in the global carbon (C) cycle, encompassing ∼30% of the 1,500 Pg of C stored in soils worldwide. However, this C is vulnerable to climate and land‐use change. Ecosystem models predict the impact of perturbation on C fluxes based on soil C pools, yet responses could vary markedly depending on soil organic matter (SOM) chemistry. Here, we show that one SOM functional group responds strongly to environmental factors and predicts the risk of carbon dioxide (CO2) release from peatlands. The molecular composition of SOM in 125 peatlands differed markedly at the global scale due to variation in temperature, land‐use, vegetation, and nutrient status. Despite this variation, incubation of peat from a subset of 11 sites revealed that O‐alkyl C (i.e., carbohydrates) was the strongest predictor of aerobic CO2 production. This explicit link provides a simple parameter that can improve models of peatland CO2 fluxes.