Holocene warming trend based on peat brGDGTs records from southeastern humid to northwestern arid China
Holocene warming trend based on peat brGDGTs records from southeastern humid to northwestern arid China
复制标题
DOI：
10.1016/j.palaeo.2023.111528
复制
发表时间：
2023-03
期刊：
影响因子：
--
通讯作者：
Shikai Wei;Z. Rao;Jiantao Cao;G. Jia;Yunxia Li;Haichun Guo;Zixian Feng;Kaiyue Guang;Qianqian Qi
中科院分区：
文献类型：
--
作者：
Shikai Wei;Z. Rao;Jiantao Cao;G. Jia;Yunxia Li;Haichun Guo;Zixian Feng;Kaiyue Guang;Qianqian Qi
最近的海洋古气候记录的综合显示了一个整体的长期全新世变暖的趋势，特别是在平均年温度（MAT），这是不一致的大陆和全球尺度上的大多数陆地记录。我们提出了一个支化甘油二烷基甘油四醚（brGDGTs）从中国中南部的石湾古田（SWGT）泥炭地的记录。从表面泥炭样品的SWGT泥炭地和周围的表层土壤的比较结果表明，brGDGT主要是原位起源，证明其潜力作为当地环境变化的记录。月观测结果表明，泥炭表层样品中5-甲基brGDGT甲基化指数（MBT'5 ME）没有季节变化，可能是MAT的一个指示因子。因此，我们的结论是，长期增加的趋势brGDGTs为基础的MBT'5 ME记录的两个平行的独立定年泥炭芯从SWGT泥炭地清楚地表明了长期变暖的趋势，在全新世。此外，我们发现，从中国东南部（SE）潮湿到西北部（NW）干旱的环境梯度沿着五个泥炭地的brGDGT记录也显示了长期的全新世变暖趋势。然而，这一趋势是相反的长期全新世变冷趋势所表明的brGDGT记录从两个泥炭地在中国东北（NE），突出了泥炭brGDGT作为气候指标的复杂性。因此，我们呼吁更多的泥炭brGDGT的研究，这是很重要的了解全新世的气候历史及其与人类活动的潜在关系。
Recent syntheses of marine paleoclimate records have revealed an overall long-term Holocene warming trend, especially in mean annual temperature (MAT), which is inconsistent with most terrestrial records on continental and global scales. We present a record of branched glycerol dialkyl glycerol tetraethers (brGDGTs) from the Shiwangutian (SWGT) peatland in central-southern China. Comparative results from surface peat samples from the SWGT peatland and the surrounding surface soils demonstrate that the brGDGTs are primarily of in-situ origin, demonstrating their potential as a record of local environmental changes. Monthly observational results show no seasonal variations in the methylation index of 5-methyl brGDGTs (MBT'5MEwhich has been proposed as an indicator of local environmental temperature in peatlands) in the surface peat samples, suggesting that it is an indicator of MAT. Thus, we conclude that the long-term increasing trend in the brGDGTs-based MBT'5MErecords of two parallel independently-dated peat cores from the SWGT peatland clearly demonstrate a long-term warming trend during the Holocene. Additionally, we found that the brGDGTs-based records from five peatlands along an environmental gradient from southeastern (SE) humid to northwestern (NW) arid China also show a long-term Holocene warming trend. However, this trend is the opposite to the long-term Holocene cooling trend indicated by brGDGTs records from two peatlands in northeastern (NE) China, highlighting the complexity of peat brGDGTs as a climatic indicator. We therefore appeal for more peat brGDGTs studies, which are important for understanding the climate history of the Holocene and its potential relationship with human activities.