Holocene Climate Change and its Effect on the Mayan Aquifer of the Yucatan Peninsula, Mexico

每年都有成千上万的加拿大人在尤卡坦半岛半岛的玛雅里维埃拉的大型度假胜地度假;在逗留期间，他们经常在附近的天然井中游泳。 大多数人都不知道这些天然井是一个巨大的地下洞穴系统的入口点，该系统延伸到度假胜地下方，是当地人口的重要含水层。 人类开发活动通过抽取地下水和废物污染，对这一含水层构成越来越大的威胁。 含水层对更大尺度的因素也非常敏感，如全球海平面上升（预计到世纪末将上升1米）以及气候变化的其他影响（如降水、飓风频率）。我的研究计划的长期目标是研究岩溶含水层的水文演变及其与全新世气候和海平面变化的关系，重点是尤卡坦半岛。 岩溶含水层在世界各地的沿海地区占主导地位，特别是在热带和亚热带地区，数千年的珊瑚礁生长加上海平面和陆地平面的变化，导致了大片多孔石灰岩。 这些岩溶含水层（近地层）是一个位于海洋水体之上的大气水，海洋水体从海岸侵入多孔石灰岩。 由于尤卡坦半岛的新近纪/第四纪石灰岩多孔，雨水渗透到地下水位，并流到海岸与大气水质量的盐度控制在盐跃层的流动模式，但关系知之甚少。 因此，尽管我们对水团在正常条件下如何相互作用有了大致的了解（仪器监测），但这种关系的复杂性还没有得到很好的理解，而且对水团如何响应全新世海平面上升和气候变化的知识也很少。 拟议的研究计划将开发一个新的古环境指标（氯）的沉积物芯重建的长期演变的尤卡坦半岛的近岸含水层，并检查与气候周期的关系，建立边界条件和未来的影响含水层。 这项研究的结果也将有助于关于大约12000 - 13000年前迁移到尤卡坦半岛的古美洲人的重要考古问题，以及关于经典玛雅人衰落的争论，这与公元8世纪和9世纪的干旱时期有关。ad. 尤卡坦半岛玛雅社会的兴衰与气候的干湿期有关，尽管这种关系的空间复杂性仍然无法解释，并且在研究人员中引起了高度争论。拟议的研究将通过重建过去4 - 5000年来含水层和湖水的盐度或（饮用性）来促进这一辩论。

Every year, thousands of Canadians vacation at large resorts on the Yucatan Peninsula's Maya Riviera; often swimming in nearby cenotes during their stay. Most are not aware that these cenotes are entry points for a vast subterranean cave system that extends beneath the resorts which is an important aquifer for the local population. This aquifer is under increased threat from human development through groundwater extraction and waste contamination. The aquifer is also very sensitive to larger scale factors such as global sea-level rise which is predicted to be 1m by the end of the 21st century, as well as other effects of climate change (e.g. precipitation, frequency of hurricanes). The long-term goal of my research program is to examine the hydrological evolution of karst aquifers and their relationship with Holocene climate and sea-level change with a focus on the Yucatan Peninsula. Karst aquifers predominate coastal areas around world, but especially in tropical and subtropical areas where millennia of reef growth coupled with sea and land-level change has resulted in large tracts of porous limestone. These karst aquifers (anchialine) are a meteoric water mass resting on top of a marine water mass that intrudes from the coast through the porous limestone. Because the Neogene/Quaternary limestone of the Yucatan peninsula is so porous, rainwater penetrates to the water table and flows to the coast with the salinity of the meteoric water mass being controlled by flow patterns at the halocline, but the relationship is poorly known. So, although we have a general understanding (instrumental monitoring) on how the water masses interact under normal conditions, the complexity of the relationship is not well understood, and there is little knowledge on how water masses responded to Holocene sea-level rise and climate change. The proposed research program will develop a new paleoenvironmental indicator (chlorine) in sediment cores for reconstructing the long-term evolution of the anchialine aquifer of the Yucatan and examine relationships with climate cycles establishing boundary conditions and future impacts on the aquifer. The outcomes from this research will also contribute to important archaeological questions regarding Paleoamericans who migrated to the Yucatan approximately 12-13,000 yrs ago, and to the debate about the decline of the Classic Maya which has been linked to a period of drought in the 8th and 9th c. AD. The rise and fall of Mayan societies in the Yucatan have been linked with climatically wet and dry periods, although there is spatial complexity in this relationship that remains unexplained and is highly debated amongst researchers. The proposed research will contribute to this debate by reconstructing the salinity or (potability) of the aquifer and lake water over the past 4-5,000 years.