Environmental and Marine Sciences Research Institute (IMEDMAR-UCV), Catholic University of Valencia, C/ Guillem de Castro 94, 46003 Valencia, Spain.
Environmental and Marine Sciences Research Institute (IMEDMAR-UCV), Catholic University of Valencia, C/ Guillem de Castro 94, 46003 Valencia, Spain.
Sci Total Environ. 2022 Feb 10;807(Pt 2):151230. doi: 10.1016/j.scitotenv.2021.151230. Epub 2021 Nov 6.
The Albufera de Valencia is one of the largest lagoon in the Spanish Mediterranean. Two continuous borehole cores reaching depths of 8 and 14 m in the northern part of the lagoon underwent sedimentological, micropaleontological and biological study. The organic content was also analysed, and C radiometric dating and amino acid racemization were performed. Study of the content of benthic foraminifera and n-alkanes and alkanoic acids in the lagoon sedimentary record identified several periods. The core records showed seven different environments: alluvial; freshwater marsh; brackish marsh; brackish lagoon; brackish lagoon with marine connection, backbarrier flat, and backshore. These environments changed due to eight phases associated with the transgression and regression of the barrier system, which caused the shift from exposed environments as the backshore with washover, to the typical low-energy lagoon and marsh deposition. The paleoenvironmental evolution described above is interpreted as a response to global climate changes. The shift from an alluvial setting to a brackish lagoon is probably related to the late of Early Holocene sea level rise ending at the Holocene Climate Optimum, when the highest sea level was reached. The persistence of the brackish lagoon, with no marine connection, is probably synchronous with dry conditions in the area (Booth et al., 2005) at the time of Bond event 3 (i.e., 4.2 ka) in the North Atlantic region (Bond et al., 2001). Finally, the arrival of large amounts of sediment triggered the accretion of the barrier, also enhancing coastal progradation until the present day. These results allow an evaluation of the impact of anthropic action on the Valencia lagoon, especially since the eighteenth century, and a short- and medium-term projection of the consequences of present-day climate change.
巴伦西亚泻湖是西班牙地中海最大的泻湖之一。泻湖北部的两口连续岩芯，深度分别达到 8 米和 14 米，对其进行了沉积学、微古生物学和生物学研究。还对有机含量进行了分析，并进行了 C 放射性测年和氨基酸外消旋化分析。对泻湖沉积物记录中底栖有孔虫和 n-烷烃及烷酸的含量进行研究，确定了几个时期。岩芯记录显示了七种不同的环境：冲积；淡水沼泽；微咸沼泽；微咸泻湖；有海洋联系的微咸泻湖、后滨障壁平原和后滨。这些环境因与障壁系统进退相关的 8 个阶段而发生变化，这导致从暴露环境（如后滨带的洪水冲刷）转变为典型的低能量泻湖和沼泽沉积。上述古环境演化被解释为对全球气候变化的响应。从冲积环境到微咸泻湖的转变可能与早全新世海平面上升有关，海平面上升在全新世气候最适宜期结束，当时达到了最高海平面。没有海洋联系的微咸泻湖的持续存在可能与该地区的干旱条件同步（Booth 等人，2005 年），当时北大西洋地区发生了邦德事件 3（即 4200 年前）（Bond 等人，2001 年）。最后，大量沉积物的到来引发了障壁的堆积，也增强了海岸的进积作用，一直持续到今天。这些结果允许评估人为活动对巴伦西亚泻湖的影响，特别是自 18 世纪以来，并对当今气候变化的短期和中期后果进行预测。
