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在当前全球变化背景下,青藏高原冰川急剧退缩严重影响着东亚地区水资源。为了有效地规划水资源,需要对高原气候变化及其机制有深入的理解。尽管在青藏高原及周边地区有大量的古气候记录,但是目前对高原气候的时空变化及其机制仍缺乏深入一致的认识。青藏高原冰川、树轮和石笋记录可以提供过去气候变化的框架,但是这些记录的分布局限于一些特定的地理区域。青藏高原上广泛分布的湖泊沉积物是研究高原气候的时空变化及其机制的优良介质。湖泊沉积物岩芯的年龄控制主要依赖于放射性碳同位素定年,但大多数高原湖泊具有碳库效应,为建立沉积岩芯年代控制需要进行碳库年龄校正所带来的年龄误差目前未有深入研究,这在某种程度上制约了利用湖泊沉积物记录研究高原气候时空变化及其机制。本文比较了目前确定高原湖泊碳库年龄的方法并提出建议采用的方法,汇总目前已发表的高原湖泊碳库年龄,讨论湖泊现代碳库年龄的空间分布及其影响因素,讨论湖泊碳库过去变化及其可能造成的岩芯年代控制误差;以青海湖和班公错两个高原湖泊已发表的记录为例讨论过去碳库年龄变化可能造成对记录完全不同的解释;还讨论了由碳库效应校正而带来的湖泊沉积物岩芯年龄控制误差对青藏高原湖泊记录的末次盛冰期终止年代的空间分布及其对变化机制解释的影响。如果考虑碳库效应的过去变化,目前所观测到的高原气候时空变化及其机制需要重新解释。因此,为了更好地理解青藏高原气候时空变化及其机制,我们需要更多有良好定年、高分辨率和定量化的湖泊记录,本文也建议在解释目前湖泊记录时需要应对年龄控制极大重视。
In the current context of global change, the dramatic retreat of glaciers on the Tibetan Plateau has seriously affected water resources in East Asia. In order to plan water resources effectively, there is a need to have a deep understanding of climate change in the plateau and its mechanisms. Although there are a large number of paleoclimate records in the Qinghai-Tibet Plateau and its surrounding areas, there is currently no deep and consistent understanding of the temporal and spatial changes of the plateau climate and its mechanism. The records of glaciers, tree rings and stalagmites in the Qinghai-Tibet Plateau can provide a framework for past climate change, but the distribution of these records is limited to a few specific geographical areas. Lake sediments widely distributed on the Qinghai-Tibet Plateau are excellent mediums for studying the spatio-temporal variations of the plateau climate and its mechanism. The age control of lacustrine cores mainly depends on the dating of radioactive carbon isotopes. However, most of the plateau lakes have the carbon pool effect. For the purpose of establishing age control of sedimentary cores, the age errors caused by the age correction of carbon pools are not yet studied in depth. To a certain extent, this restricted the use of lake sediment records to study the spatio-temporal variations of plateau climate and their mechanisms. This paper compares the present methods for determining the age of carbon pools in plateau lakes and puts forward some suggestions to summarize the current published carbon pool age in plateau lakes and discuss the spatial distribution of modern carbon pools in lakes and their influencing factors, And the possible control errors of the cores in the core. Taking the published records of two plateau lakes such as Qinghai Lake and Baigongchu as an example, it is possible to explain completely different explanations of records from the past age variations of carbon pools. The carbon stock effect Correction of age control errors caused by lacustrine sediments on the spatial distribution of termination of the last glaciation recorded by the Qinghai - Tibet Plateau lakes and its impact on the explanation of the change mechanism. If we consider the past changes of carbon stock effects, the spatial and temporal changes observed in the plateau climate and their mechanisms need to be reinterpreted. Therefore, we need more time-lapse, high-resolution and quantitative lake records in order to better understand the temporal and spatial variations of climate over the Tibetan Plateau. This paper also suggests that we should pay great attention to age-control when interpreting current lake records .