Should Aquatic CO2 Evasion be Included in Contemporary Carbon Budgets for Peatland Ecosystems?
Should Aquatic CO2 Evasion be Included in Contemporary Carbon Budgets for Peatland Ecosystems?
复制标题
水生二氧化碳逃逸是否应该纳入泥炭地生态系统的当代碳预算中？
DOI：
10.1007/s10021-014-9838-5
复制
发表时间：
2015
期刊：
影响因子：
3.7
通讯作者：
Billett M
中科院分区：
文献类型：
--
作者：
Billett M
量化的北方泥炭地的汇强度需要测量或所有主要的C通量项的现实的估计。虽然净生态系统碳平衡（NECB）的评估通常包括每年的净生态系统交换和溶解有机碳（DOC）的横向通量的测量，他们很少包括逃逸（脱气）的CO2和CH4从水面到大气中的估计，尽管过饱和是泥炭地流的一致特征。英国温带泥炭地溪流的瞬时气体交换测量结果表明，整个流域的CO2逃逸通量是水生C通量的重要组成部分（23.3 ± 6.9 g C m − 2流域y − 1），其大小与下游DOC通量（29.1 ± 12.9 g C m − 2流域y − 1）相当。如果逃逸的CO2和CH4是同位素"年轻"的，并来自"生态系统内"的来源，如泥炭或流中处理的DOC，则在NECB中包含逃逸通量项是合理的。从"老"的生物源或地质源的推导将表明一个单独的起源和年龄的C固定，断开的生态系统积累率，NECB的定义意味着。逃逸CO2和DOC的δ 13 C和14 C双同位素分析结果表明，两者的来源和年龄不同，逃逸CO2主要来源于外来（非河流）源。虽然逃避是一个重要的通量长期相对于其他组件的NECB，同位素数据表明，其来源和年龄是泥炭地特定的。有证据表明，一个组成部分的CO2-C逃避流表面最初固定从大气中在一个显着更早的时间（前AD 1955年）比现代（后AD 1955年）通过光合作用固定C。
Quantifying the sink strength of northern hemisphere peatlands requires measurements or realistic estimates of all major C flux terms. Whilst assessments of the net ecosystem carbon balance (NECB) routinely include annual measurements of net ecosystem exchange and lateral fluxes of dissolved organic carbon (DOC), they rarely include estimates of evasion (degassing) of CO2and CH4from the water surface to the atmosphere, despite supersaturation being a consistent feature of peatland streams. Instantaneous gas exchange measurements from temperate UK peatland streams suggest that the CO2evasion fluxes scaled to the whole catchment are a significant component of the aquatic C flux (23.3 ± 6.9 g C m−2catchment y−1) and comparable in magnitude to the downstream DOC flux (29.1 ± 12.9 g C m−2catchment y−1). Inclusion of the evasion flux term in the NECB would be justified if evaded CO2and CH4were isotopically “young” and derived from a “within-ecosystem” source, such as peat or in-stream processing of DOC. Derivation from “old” biogenic or geogenic sources would indicate a separate origin and age of C fixation, disconnected from the ecosystem accumulation rate that the NECB definition implies. Dual isotope analysis (δ13C and14C) of evasion CO2and DOC strongly suggest that the source and age of both are different and that evasion CO2is largely derived from allochthonous (non-stream) sources. Whilst evasion is an important flux term relative to the other components of the NECB, isotopic data suggest that its source and age are peatland-specific. Evidence suggests that a component of the CO2-C evading from stream surfaces was originally fixed from the atmosphere at a significantly earlier time (pre-AD1955) than modern (post-AD1955) C fixation by photosynthesis.
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影响因子：
1.1
作者：
Billett, M. F.;Charman, D. J.;Rose, R.
通讯作者：
Rose, R.
从地表水逃逸到大气中损失的二氧化碳的同位素组成：直接和间接方法的方法比较
DOI：
--
发表时间：
2010
期刊：
影响因子：
--
作者：
M. Billett;M. Garnett
通讯作者：
M. Garnett
影响因子：
11.6
作者：
Holden, Joseph;Smart, Richard P.;Chapman, Pippa J.
通讯作者：
Chapman, Pippa J.
影响因子：
5.4
作者：
Dinsmore, K. J.;Billett, M. F.
通讯作者：
Billett, M. F.