干旱区地理2011，Vol.34Issue(2)：243-251,9.
柴达木盆地大浪滩130ka BP以来的孢粉组合与古气候
Sporo-pollen assemblage and palaeoenvironment since 130 ka BP in Dalangtan Lake of Qaidarn Basin
摘要
Abstract
This paper obtained the data of the cores based on U-series age from ZK02 borehole at ridge of Dalangtan in the western Qaidam basin, where 34 samples from the sludge containing gypsum silt were selected of select for 130 ka BP (90.5 m and above) and the pollen analysis was done. Based on the pollen characteristics, the assemblage of the pollen from the bottom upwards can be divided into six zones to analyze the ancient vegetation succession in the last interglacial (130 ka BP) state in this area. The results showed as follows: in the period of 130 ka BP (the last interglacial period), the vegetation in the western Qaidam basin obviously changed compared with the very significant environment. Overall, the spruce, fir and pine trees consisted of some cold temperate coniferous forest had expanded for five times to the surrounded Zhongshan area, and even extends towards the basin. But thegrass of Gramineae, Compositae, Artemisia as the main component occupied the basin, which showed the climate that was mild climate controlled by the summer monsoon flow from the East Asia to the West, while vegetation flourished, the enhanced soil expanded, water being desalinized, the lake larger in the interstadial period, particularly that in the first pollen assemblage I ( 130 -92 ka BP) and the pollen assemblage IV (56.2 -49 ka BP) in the duration of sedimentation when the plant diversity increased. In addition to the grassland vegetation in the basin, on the wetlands around the lake the plant was growing quite flonrishing, which demonstrated that the two periods were the most enhanced summer monsoon circulation with more adequate rainfall and the forest expanding fast in the mountains. The river flow was incresing and salt lake became desaltinized. The emergent grasses were growing at the edge of the marsh in the lake area. In particular in 49 ka BP ago or so, coniferous forest was growing associated with mountain cedar. Thus it suggested that the place was affected by the southwest moist flow, which made the flora of Himalayan cedar grow in the mountainous area of the western Qaidam. Although the pollen study reveals the vegetation and environmental changes in the last interglacial period in the western Qaidam Basin which concentrated a great concern in the project of the global changes in the past (PAGES). But the lack of exposed pollen in the salt layer in the hole and pollen percentage and pollen collection rate in the area on current and past vegetation correction cannot be enough to expore the recent 130 thou. years of the process of vegetation and climate change and the formation mechanism in the western Qaidam, therefore, only when the more palynological evidence is obtained from the more boreholes which make accurate resolution of pollen data support related to the disciplines.关键词
孢粉分析/铀系测年/末次间冰期/古植被/古环境/柴达木盆地Key words
pollen analysis/last interglacial period/ palaeo-vegetation palaeo-environment/ the Qaidam basin分类
天文与地球科学引用本文复制引用
侯献华,郑绵平,杨振京,杨庆华,毕志伟..柴达木盆地大浪滩130ka BP以来的孢粉组合与古气候[J].干旱区地理,2011,34(2):243-251,9.基金项目
本文由矿产资源研究所基本科研业务费(K0915)、地质调查项目(编号:1212011018004)和国家自然科学基金项目(40972212)共同资助 （K0915）
