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文章讨论了末次冰消开始时期青藏高原南部普莫雍错湖芯沉积反映的环境暖湿化以及原因。通过对现代湖泊和周边河流水文状况调查,发现流域内发育众多冰川,冰川融水构成维持湖面稳定的重要来源;湖面以及湖泊沉积环境的变化与冰川融水以及相应的温度改变具有密切的联系。利用湖泊沉积岩芯PM-1孔,通过加速器14C测年和粒度、元素、碳酸盐含量、总有机碳以及有机碳同位素、总氮、分子标志化合物、孢粉等环境指标的分析,发现在16.4~15.4cal.kaB.P.有大量流水进入湖泊,使湖面扩大,湖水加深;流域地表产生大量有机碎屑,并被流水带入湖泊进行沉积;流域内的喜湿植被得以发展。该时段湖泊扩张、陆源植被发展的原因一方面得益于冰期过后气候向温暖湿润方向转化,另一方面温度上升带来大量冰川融水则可能具有更加重要的影响,对于深入理解当前青藏高原冰川普遍退缩和一些湖泊的水面上涨具有重要的参考价值。
The paper discusses the environmental warming and wetting of the core of the Pomorong Lake in the southern part of the Qinghai-Tibet Plateau at the beginning of the ice-depleting period and its causes. Based on the investigation of hydrological conditions in modern lakes and surrounding rivers, it is found that many glaciers are developed in the basin. Melting glaciers constitute an important source of maintaining lake stability. Changes in lake and lacustrine sediments are closely related to glacial meltwater and corresponding temperature changes. Analysis of environmental indicators such as age, grain size, elemental and carbonate contents, total organic carbon, organic carbon isotopes, total nitrogen, molecular markers and sporopollen in lacustrine core sediments by PM- ~ 15.4cal.kaB.P. There is a large amount of water flowing into the lake to expand the lake surface and deepen the lake water. A large amount of organic debris is produced on the surface of the river basin and brought into the lake by flowing water for sedimentation. The hi-wet vegetation in the basin is developed. The reasons for the expansion of terrestrial vegetation and terrestrial vegetation during this period are due to the fact that the climate is transformed to warm and humid climate after glacial period, and the melting of glaciers caused by the temperature rise may have a more important influence. On the other hand, The general retreat and the rising water level of some lakes have important reference value.