Reconstruction of a paleo-lakesystem at UNESCO World Heritage Site Tsodilo Hills, Kalahari, Botswana: MIS3 and MIS2 ecosystem dynamics, climate, weather and environmental variations derived from sedimentation processes and bio-indicators

博茨瓦纳卡拉哈里联合国教科文组织世界遗产地措迪洛山古湖泊系统的重建：来自沉积过程和生物指标的 MIS3 和 MIS2 生态系统动态、气候、天气和环境变化

• 批准号: 281420578
• 负责人: Dr. Kai Hartmann
• 金额: --
• 依托单位: Fachrichtung Paläontologie
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2015
• 资助国家: 德国
• 起止时间: 2014-12-31 至 2022-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/281420578?language=en
• 关键词: Reconstruction; paleo; lakesystem; UNESCO; World

Natural permanent lakes are recently an exception in the Kalahari. The geology and precipitation patterns inhibit a long lasting existence. However, during Late Pleistocene and Holocene time large lakes spanned a considerable part of the recent semi-arid Kalahari basin. The palaeolakes indicate a much higher groundwater level under different climate conditions.An outstanding example is the former Tsodilo lake in northwestern Botswana within the basin of the Okavango Delta. The correspondent small inselberg chain frames a ca. 30 km2 wide basin with fossil-bearing lake carbonates to the east. With one of the highest concentrations of rock art in the world (4500 rock paintings over an area of less than 10 km2), Tsodilo has been called the 'Louvre of the Desert' and inscribed in the list of UNESCO World Heritage Cultural Sites in 2001. Human activities and environmental change are documented in and around the hills. Prior investigations of mostly British researchers revealed the existence of an at least periodically extensive lake during time slices of some thousand years since ca. 40000 years ago until the end of the last glacial time. Likely this lake provided the livelihood for the stone-age hunters and gatherers. Lacustrine fossils provide evidence of changing water quality and sedimentation patterns. So far neither the maximum extents of the former lake nor the hydro-climate conditions responsible for long-term existence have been reconstructed. The aim of this project is a “holistic” reconstruction of the lake ecosystem dynamics and its vicinity as well as the responsible hydro-climatic preconditions. Hereby, geomorphological analyses and the geochemical/physical properties of the sediments will enable a reconstruction of processes (e.g. run-off, dune movement, etc.) affecting the former landscape. Therefore, e.g. statistical algorithms applied on high-resolution grainsize distributions shall unravel settings and quantify transport processes while multivariate geochemical/mineralogical data analyses will provide information about the water budget. Isotope data from gastropod shells shall reveal information about the seasonality of precipitation. The latter may indicate former predominant atmospheric circulation pattern in southern Africa. Fossils will provide further information about water temperature, depth and nutrition content of the lake. This information will enable us to estimate the resources provided by the lake and the risks (e.g. bilharziosis) for the people. In case of sufficient preservation of fossil pollen during certain time slices, the reconstruction of palaeo-vegetation will provide an estimation of temperature and precipitation changes as well as a derivation of diversity and density of huntable wildlife.

天然的永久性湖泊最近在卡拉哈里沙漠是一个例外。地质和降水模式抑制了长期存在。然而，在晚更新世和全新世时期，大型湖泊跨越了现代半干旱喀拉哈里盆地的相当一部分。古湖泊表明，在不同的气候条件下，地下水位都高得多，一个突出的例子是位于博茨瓦纳西北部奥卡万戈三角洲盆地内的前措迪洛湖。通讯员小因塞尔伯格链框架一个CA。30平方公里宽的盆地，东部为含化石的湖泊碳酸盐岩。作为世界上岩石艺术最集中的地区之一（在不到10平方公里的面积上有4500幅岩画），Tsodilo被称为“沙漠卢浮宫”，并于2001年被列入联合国教科文组织世界文化遗产名录。人类活动和环境变化都记录在山上和周围。大多数英国研究人员先前的调查显示，自公元前1000年以来，在大约一千年的时间段内，至少存在一个周期性的广泛湖泊。4万年前，直到最后一个冰川期结束。很可能这个湖为石器时代的猎人和采集者提供了生计。湖泊化石提供了水质变化和沉积模式的证据。到目前为止，既没有重建前湖的最大范围，也没有重建长期存在的水文气候条件。该项目的目的是“整体”重建湖泊生态系统动态及其附近地区以及负责任的水文气候先决条件。因此，地貌分析和沉积物的地球化学/物理特性将能够重建过程（例如径流、沙丘移动等）。影响了前景观。因此，例如，应用于高分辨率粒度分布的统计算法应解开设置和量化运输过程，而多元地球化学/矿物学数据分析将提供有关水预算的信息。腹足类贝壳的同位素数据将揭示降水季节性的信息。后者可能表明南部非洲以前的主要大气环流模式。化石将提供有关湖水温度、深度和营养成分的进一步信息。这些信息将使我们能够估计湖泊提供的资源和对人民的风险（例如血吸虫病）。如果在某些时间段内花粉化石得到充分保存，古植被的重建将提供温度和降水变化的估计，以及可狩猎野生动物多样性和密度的推导。