渭南地区全新世以来的孢粉组合与古环境

发布时间：2018-05-20 11:32

  本文选题：渭南 + 孢粉　； 参考：《石家庄经济学院》2015年硕士论文

【摘要】：随着对黄土-古土壤的认识及其古气候意义的确定,尤其是近几十年以来国际上古气候研究的发展,在很大程度上推动了我国黄土-古土壤的古气候研究,试图将古气候的定性描述发展成为定量的科学探索。此次一共采集黄土高原表土花粉样品196个,植被样方调查196个,首次在黄土高原地区进行大区域高密度表土孢粉样品采集并同步进行现代植被调查,利用黄土高原地区表土孢粉资料并初步建立了表层黄土孢粉-植物生态-气候关系。渭南是我国黄土高原地区古环境研究的热点地区之一。结合渭南6米深的剖面,一共取样并分析孢粉样品150个,定量重建了渭南地区全新世以来的古气候演变过程。在14.64~8.49ka B.P阶段,年平均温度8.39℃,年平均降水量为178.8mm。在8.49~5.036ka B.P阶段,年平均温度为14.63℃,年平均降水量为245.51mm。在5.036~3.58ka B.P阶段,年平均温度12.56℃,平均降水量为年261.06mm。在3.58~3.29ka B.P阶段,年平均温度7.90℃,年平均降水量为205.87mm。在3..29~至今阶段,年平均温度8.91℃,年平均降水量为123.76mm。定量重建渭南地区全新世年来的气候变化表明,渭南地区全新世变化与经典的全新世变化大致相符,变化的规律是全新世早期总体表现为快速升温降水明显增多,而在全新世的中期,是气温最高降水量最多的最佳气候时期。全新世晚期以来,该区气候再次有温度降低降水量减小的变化趋势。重建黄土高原气候变化历史是了解世界全球气候变化的桥梁,深入了解古气候变化特征,不仅可以了解不同周期内气候变化特征和机制,还可以为预测未来气候变化提供资料,定量探索恢复黄土高原渭南地区的气候变化对探索该地区乃至全国的生态环境演化和发展均具有重要意义。
[Abstract]:With the understanding of loess and paleosol and the determination of paleoclimate significance, especially the development of international paleoclimate research in recent decades, the paleoclimate research of loess paleosol in China has been promoted to a great extent. This paper attempts to develop the qualitative description of paleoclimate into a quantitative scientific exploration. A total of 196 pollen samples and 196 vegetation samples were collected from the topsoil of the Loess Plateau. For the first time, the pollen samples of the high-density topsoil in the Loess Plateau were collected and the modern vegetation survey was carried out simultaneously. Based on the surface soil pollen data in the Loess Plateau, the relationship between surface loess sporopollen, plant ecology and climate was preliminarily established. Weinan is one of the hotspots in the study of paleoenvironment in the Loess Plateau of China. The paleoclimate evolution process since Holocene in Weinan area has been quantitatively reconstructed by taking and analyzing 150 sporopollen samples at a depth of 6 meters in Weinan area. In the 14.64~8.49ka B.P stage, the annual average temperature is 8.39 鈩，

本文编号：1914447