Carbon preservation in humic lakes; a hierarchical regulatory pathway.
Carbon preservation in humic lakes; a hierarchical regulatory pathway.
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腐殖质湖泊的碳保存；
DOI：
10.1111/gcb.12066
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发表时间：
2013
影响因子：
11.6
通讯作者：
Fenner N
中科院分区：
文献类型：
--
作者：
Fenner N
泥炭地集水区储存了大量的碳。腐殖湖泊和水池是这些Meta生态系统中陆源碳的主要容器，代表封存热点;北方湖泊单独储存。120 Pg C.但人们对保护水生碳储存的机制知之甚少。在这里，我们确定了与“传统”限制有关的分解调节途径，即缺氧，抑制腐烂的化合物，低营养和酸度，使用vitromanipulation，mesocosms和自然梯度。我们表明，缺氧代表了一个强大的层次保护机制，影响所有主要限制分解和重新捕获碳，否则会逃离泥炭地。氧对氧化酶和营养循环酶的微生物合成的限制，通过允许抑制剂积累和降低营养物质来防止有机物分解为CO2，CH 4和N2 O。然而，这一途径对直接的营养物质输入敏感，因此富营养化可能通过急剧增加的温室气体排放引发对全球变暖的灾难性反馈。识别这些特定过程的限制应该为更好地管理和保护这些重要系统提供信息。
Peatland catchments store vast amounts of carbon. Humic lakes and pools are the primary receptacles for terrigenous carbon in these meta‐ecosystems, representing sequestration hotspots; boreal lakes alone storeca. 120 Pg C. But little is known about the mechanisms that preserve aquatic carbon stocks. Here, we determined the regulatory pathway of decomposition in relation to ‘traditional’ limitations, namely anoxia, decay inhibiting compounds, low nutrients and acidity, usingin vitromanipulation, mesocosms and natural gradients. We show that anoxia represents a powerful hierarchical preservation mechanism affecting all major limitations on decomposition and recapturing carbon that would otherwise escape from peatlands. Oxygen constraints on microbial synthesis of oxidases and nutrient‐cycling enzymes, prevents the decay of organic matter to CO2, CH4and N2O by allowing inhibitor accumulation and lowering nutrients. However, this pathway is sensitive todirectnutrient inputs and therefore eutrophication could initiate catastrophic feedback to global warmingviadramatically increased greenhouse gas emissions. Identifying these process‐specific limitations should inform better management and conservation of these vital systems.