Holocene Paleohydrology of the Subtropical Andes from Lake Records

Am-9613991塞尔策，杰弗里·O·锡拉丘兹大学论文题目：亚热带安第斯山脉的全新世古水文学该项目的主要目标是建立亚热带安第斯山脉全新世古气候记录。以前的工作表明，在中全新世期间会有较长的干旱时期，然而，需要更多的工作来产生硅藻和同位素记录，以证实这一假设并确定这种干燥阶段的程度。具体地说，该奖项将支持一项研究，以确定安第斯高原降水-蒸发平衡在全新世十年至世纪时间尺度上发生变化的时间。这些记录对于了解亚热带的长期大气动态和评估夏季对流强度从十年到千年尺度变化的重要性是必要的。通过对高分辨率湖心的沉积物、地球化学、磁性、同位素和硅藻含量的分析，重建该地区全新世的气候历史。将对玻利维亚东部科迪莱拉地区从南纬150度到南纬20度的横断面进行调查。这种有效湿度变化的记录将提供对南美洲亚热带气候长期变化的洞察。水资源的变化也可能对生活在高原上的史前居民产生重大影响，并可能再次成为该区域未来人口的一个重要环境因素。

Abstract ATM-9613991 Seltzer, Geoffrey O. Syracuse University Title: Holocene Paleohydrology of the Subtropical Andes from Lake Records The primary objective of this project is to establish new multi- proxy Holocene paleoclimate records from the subtropical Andes. Previous work suggests a prolonged period of aridity during the mid-Holocene, however, more work to produce diatom and isotope records is necessary to confirm this hypothesis and determine the extent of this dry phase. Specifically, this award will support a study to define the timing of changes in the precipitation- evaporation balance of the Andean Altiplano on a decadal to century timescale for the Holocene. These records are needed to understand the long-term atmospheric dynamics of the subtropics and to assess the importance of decadal to millennial-scale shifts in the strength of summer convection. The Holocene climate history of the region will be reconstructed by analyzing the sediment, geochemical, magnetic, isotopic, and diatom content of lake cores dated at high-resolution by 210Pb and AMS 14C measurements. A transect of sites ranging from approximately 15o to 20oS in the eastern cordillera of Bolivia will be investigated. Such a record of changing effective moisture will provide insight into the long- term climate variability of subtropical South America. Changes in water resources may have also significantly impacted prehistoric people living on the Altiplano and may again be an important environmental factor for future populations in the region.