干旱区研究 ›› 2022, Vol. 39 ›› Issue (3): 667-675.doi: 10.13866/j.azr.2022.03.01

• 泛第三极环境与绿色丝路 •    下一篇

全新世西风模态下中亚干旱区孢粉类型多样性变化特征——以阿尔泰山为例

张东良1,2,3()   

  1. 1.中国科学院新疆生态与地理研究所,新疆 乌鲁木齐 830011
    2.中国科学院中亚生态与环境研究中心,新疆 乌鲁木齐 830011
    3.中国科学院大学,北京 100049
  • 收稿日期:2021-12-06 修回日期:2022-01-13 出版日期:2022-05-15 发布日期:2022-05-30
  • 作者简介:张东良(1990-),男,副研究员,主要研究中亚干旱区全新世气候与植被变化. E-mail: zhdl@ms.xjb.ac.cn
  • 基金资助:
    中国科学院青年创新促进会项目(2022447);国家自然科学基金青年项目(41803024)

Changes of pollen taxa diversity in the arid Central Asia under the Holocene Westerlies Mode: A case study of the Altai Mountains

ZHANG Dongliang1,2,3()   

  1. 1. Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi 830011, Xinjiang, China
    2. Research Center for Ecology and Environment of Central Asia, Chinese Academy of Sciences, Urumqi 830011, Xinjiang, China
    3. University of Chinese Academy of Sciences, Beijing 100049, China
  • Received:2021-12-06 Revised:2022-01-13 Online:2022-05-15 Published:2022-05-30

摘要:

气候变暖对中亚干旱区植物带来了巨大的威胁。因观测时间受限,我们无法更好地理解长时间尺度干旱区植物多样性与气候变化之间的关系。但地质记录中的孢粉给我们提供了机会来理解过去植物存在、分布和多样性特征。以阿尔泰山为例,选择不同海拔的3个孢粉序列(高海拔-哈拉萨孜泥炭、中海拔-娜仁夏泥炭和低海拔-喀纳斯湖)来研究孢粉类型多样性变化特征及其对全新世气候变化的响应模式。结果显示:(1) 阿尔泰山全新世孢粉类型多样性变化呈现出独特的格局。详细来说,全新世早期随着气候的变暖,森林上限开始向上迁移,使得高海拔孢粉类型多样性增加。(2) 全新世中期气候暖湿,森林上限和下限的向上和向下迁移使得高低海拔孢粉类型多样性较高,但以泰加林主导的森林带孢粉类型多样性偏低,主要归咎于物种均匀度的下降。(3) 全新世晚期气候变冷且更湿润,森林带上限向下移动,使得中海拔孢粉类型多样性显著提高。全新世阶段森林带内孢粉类型多样性变化幅度最大,该区域是气候响应最敏感区和最脆弱区。本研究有助于我们掌握山地植被带对全新世气候变化的响应模式,为探索山地植被迁移历史提供关键证据。

关键词: 全新世, 孢粉类型多样性, 阿尔泰山, 干旱区, 中亚

Abstract:

Modern climate change poses a huge threat to plants in the arid Central Asia. Due to the short instrumental interval, we are unable to better understand the long time-scale relationship between plant diversities and climate change in this region. However, pollen records in the geological archives provide us an opportunity to understand the existence, distribution and diversity of plants in the past. In this study, we selected three pollen sequences from different elevations (Halasazi Peat, Narenxia Peat and Kanas Lake) in the Altai Mountains to investigate the characteristics of plant diversities and their response patterns to Holocene climate change. The results revealed that the changes of pollen taxa diversity in the Altai Mountains showed a unique pattern. As the climate was warming in the early Holocene, the upper forest limits began to migrate upward, leading to an increase in pollen taxa diversity at high elevations. In the middle Holocene, the climate was warm and wet, and the upward and downward migration of the upper and lower forest limits resulted in higher diversities at high and low elevations, but the lower diversities in the taiga-dominated forest belt mainly resulted from a decreasing species evenness. In the late Holocene, the climate became cooler and wetter, and the upper forest limits moved downward, leading to a significant increase in diversities at middle elevations. The largest changes of plant diversities were observed in the forest belt during the Holocene, which means this belt is the most sensitive and vulnerable area for climate response. This study not only helps us understand the response model of mountain vegetation belt to Holocene climate change, and also provides key evidence for exploring the history of mountain vegetation migration in the arid Central Asia.

Key words: Holocene climate, pollen taxa diversity, Altai Mountains, arid zone, Central Asia