Holocene carbon dynamics at the forest-steppe ecotone of southern Siberia.
Holocene carbon dynamics at the forest-steppe ecotone of southern Siberia.
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DOI：
10.1111/gcb.13583
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发表时间：
2017-05
影响因子：
11.6
通讯作者：
Swann GE
中科院分区：
文献类型：
--
作者：
Mackay AW;Seddon AW;Leng MJ;Heumann G;Morley DW;Piotrowska N;Rioual P;Roberts S;Swann GE
西伯利亚南部的森林-草原交错带对气候变化非常敏感;全球变暖预计将把该交错带推向北方，同时导致下面的永久冻土退化。为了更深入地了解长期森林草原碳动态，我们使用了一种基于贝加尔湖沉积物记录的高分辨率、多代理、古湖泊学方法。我们重建了与理解碳动力学相关的代用指标，包括碳质量积累速率（CMAR; g C m−2 yr−1）和有机质同位素组成（δ 13 CTOC）。森林草原动态重建使用花粉，硅藻记录提供的措施，从附近和关闭海岸社区的初级生产。我们使用广义加性模型（GAM）来识别时间序列中的显著变化点，并通过将广义线性最小二乘回归模型应用于多代理数据的组成部分，我们解决了（1）在全新世早期变暖和全新世晚期变冷期间，哪些因素影响碳动态？(2)碳动力学如何应对突然的次米兰科维奇规模事件？贝加尔湖全新世的碳储量预算是多少。CMAR值介于2.8和12.5 g C m−2 yr−1之间。峰值埋葬率（和最大的变化）发生在全新世早期，与融化的永久冻土和退缩的冰川，而最低的埋葬率发生在新冰期。10.3、4.1和2.8 kyr bp的碳动态的显著变化为该地区对气候变化的次米兰科维奇驱动因素的敏感性提供了令人信服的证据。我们估计，在全新世期间，贝加尔湖沉积物中埋藏了1.03 Pg C，其中近四分之一是在全新世早期埋藏的。结合起来，我们的研究结果强调了理解西伯利亚南部环境中碳循环和水文过程之间密切联系的重要性，而不仅仅是温度。西伯利亚南部的森林-草原交错带对气候变化非常敏感;全球变暖预计将把该交错带推向北方，同时导致下面的永久冻土退化。为了更深入地了解长期森林草原碳动态，我们使用了一种基于贝加尔湖沉积物记录的高分辨率、多代理、古湖泊学方法。广义加性模型识别时间序列中的显著变化点，我们将其与突发的次米兰科维奇尺度事件联系起来。自全新世开始以来，贝加尔湖沉积物中埋藏了约1.03 Pg的C，其中近四分之一的预算在最初的几千年内被埋藏。
The forest–steppe ecotone in southern Siberia is highly sensitive to climate change; global warming is expected to push the ecotone northwards, at the same time resulting in degradation of the underlying permafrost. To gain a deeper understanding of long‐term forest–steppe carbon dynamics, we use a highly resolved, multiproxy, palaeolimnological approach, based on sediment records from Lake Baikal. We reconstruct proxies that are relevant to understanding carbon dynamics including carbon mass accumulation rates (CMAR; g C m−2 yr−1) and isotope composition of organic matter (δ 13 CTOC). Forest–steppe dynamics were reconstructed using pollen, and diatom records provided measures of primary production from near‐ and off‐shore communities. We used a generalized additive model (GAM) to identify significant change points in temporal series, and by applying generalized linear least‐squares regression modelling to components of the multiproxy data, we address (1) What factors influence carbon dynamics during early Holocene warming and late Holocene cooling? (2) How did carbon dynamics respond to abrupt sub‐Milankovitch scale events? and (3) What is the Holocene carbon storage budget for Lake Baikal. CMAR values range between 2.8 and 12.5 g C m−2 yr−1. Peak burial rates (and greatest variability) occurred during the early Holocene, associated with melting permafrost and retreating glaciers, while lowest burial rates occurred during the neoglacial. Significant shifts in carbon dynamics at 10.3, 4.1 and 2.8 kyr bp provide compelling evidence for the sensitivity of the region to sub‐Milankovitch drivers of climate change. We estimate that 1.03 Pg C was buried in Lake Baikal sediments during the Holocene, almost one‐quarter of which was buried during the early Holocene alone. Combined, our results highlight the importance of understanding the close linkages between carbon cycling and hydrological processes, not just temperatures, in southern Siberian environments. The forest–steppe ecotone in southern Siberia is highly sensitive to climate change; global warming is expected to push the ecotone northwards, at the same time resulting in degradation of the underlying permafrost. To gain a deeper understanding of long‐term forest–steppe carbon dynamics, we use a highly resolved, multiproxy, palaeolimnological approach, based on sediment records from Lake Baikal. Generalized additive models identify significant change points in temporal series, which we relate to abrupt sub‐Milankovitch scale events. About 1.03 Pg of C has been buried in Lake Baikal sediments since the start of the Holocene, with almost one‐quarter of budget being buried within the first few thousand years.
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影响因子：
2.3
作者：
Arz, Helge W.;Lamy, Frank;Paetzold, Juergen
通讯作者：
Paetzold, Juergen
影响因子：
56.9
作者：
Bond, G;Showers, W;Bonani, G
通讯作者：
Bonani, G
影响因子：
11.6
作者：
Anderson, N. J.;Bennion, H.;Lotter, A. F.
通讯作者：
Lotter, A. F.
影响因子：
3
作者：
Brincat, D;Yamada, K;Naraoka, H
通讯作者：
Naraoka, H
DOI：
10.1608/frj-7.2.811
发表时间：
2014-01-01
期刊：
Freshwater Reviews
影响因子：
--
作者：
Anderson, N. John
通讯作者：
Anderson, N. John