Mid-Holocene Iberian hydroclimate variability and paleoenvironmental change: molecular and isotopic insights from Praia Rei Cortiço, Portugal: MID-HOLOCENE IBERIAN HYDROCLIMATE AND PALEOENVIRONMENTAL CHANGE
Mid-Holocene Iberian hydroclimate variability and paleoenvironmental change: molecular and isotopic insights from Praia Rei Cortiço, Portugal: MID-HOLOCENE IBERIAN HYDROCLIMATE AND PALEOENVIRONMENTAL CHANGE
复制标题
全新世中期伊比利亚水文气候变化和古环境变化：葡萄牙 Praia Rei Cortiço 的分子和同位素见解：中全新世伊比利亚水文气候和古环境变化
DOI：
10.1002/jqs.3000
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发表时间：
2018
影响因子：
2.3
通讯作者：
Lane, Chad S.
中科院分区：
文献类型：
--
作者：
Taylor, Audrey K.;Benedetti, Michael M.;Haws, Jonathan A.;Lane, Chad S.
在葡萄牙沿海的Praia Rei Cortiço（PRC），我们分析了植物蜡衍生烷烃的化合物特异性同位素，结合分子分布代理和C/N比，以重建中全新世湿地的水文和环境变化。在这一相对短暂的全新世时期（6.6-5.4k cal aBP），陆源C29正构烷烃（δDn‐C29）的稳定氢同位素组成发生了重大变化，记录了降水来源和风暴轨迹的显著数十年变化。湿地的形成在PRC发生在一个潮湿的间隔（6.6-6.5k cal aBP）与占主导地位的热带降水源，可能是一个持续的负相的北大西洋涛动，这使得建立和优势ofSphagnummoss的结果。随后降水量的减少显著降低了PRC的泥炭藓丰度，这可以通过沉积物C/N比的降低和中链正烷烃丰度的降低来证明。从5.9到5.4 kcal aBP，相对较低的δ Dn-C29值与沿着伊比利亚海岸的沙入侵和北大西洋的冷却相一致。在此期间，深海沉积物岩芯中记录的δDn‐ C29值与冰筏碎片的出现之间的强烈对应关系表明，北大西洋对伊比利亚中纬度风暴和降水系统的轨迹具有明显的控制作用。
At Praia Rei Cortiço (PRC), coastal Portugal, we analyzed compound‐specific isotopes of plant wax‐derivedn‐alkanes in combination with molecular distribution proxies and C/N ratios to reconstruct hydrologic and environmental change in a mid‐Holocene wetland. During this relatively brief segment of the Holocene (6.6–5.4k cal aBP), substantial shifts in the stable hydrogen isotope composition of terrestrially sourced C29n‐alkanes (δDn‐C29) record significant multi‐decadal changes in precipitation origin and storm trajectory. Wetland formation at PRC occurred during a humid interval (6.6–6.5k cal aBP) with a dominantly tropical precipitation source, likely the result of a persistent negative phase of the North Atlantic Oscillation, which permitted the establishment and dominance ofSphagnummoss. A subsequent decrease in precipitation significantly reducedSphagnumabundance at PRC, which is evidenced by decreased sedimentary C/N ratios and reduced mid‐chainn‐alkane abundances. From 5.9 to 5.4k cal aBP, relatively low δDn‐C29values coincide with sand invasion along the Iberian coast and cooling in the North Atlantic. Strong correspondence between δDn‐C29values and the occurrence of ice‐rafted debris recorded in deep sea sediment cores during this period illustrate a marked North Atlantic control on the trajectory of mid‐latitude storms and precipitation regimes in Iberia.