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脆弱的中国沼泽树森林的崩
Ning Wang1, Ping Ding1, Xingfang Ding2
1State Key Laboratory of Deep Earth Processes and Resources, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China.
Science advances
|April 23, 2025
概括
人类活动,而不是气候变化,导致了珍珠河三角洲Glyptostrobus pensilis森林的末期Holocene灭绝. 与汉族征服有关的火灾摧毁了这些古老的树木.
科学领域:
- 古植物学是古植物学.
- 环境历史 环境历史
- 考古学的考古学
背景情况:
- 三级遗迹物种*Glyptostrobus pensilis*曾经在珍珠河三角洲丰富,但在Holocene晚期急剧下降.
- 这种下降的确切原因仍在争论中,同时考虑气候变化和人类的影响.
研究的目的:
- 调查珍珠河三角洲 *Glyptostrobus pensilis* 减少和几乎灭绝的主要驱动因素.
- 确定人类干扰与气候变化在物种晚期Holocene人口崩中的作用.
主要方法:
- 沉积物核心的古生物学分析,以重建植被历史.
- 主要组件分析 (PCA) 用于确定环境和人为因素.
- 放射性碳 (C) 测年法确定了森林衰退的精确时间表.
- 分析木炭和金属度以检测火灾事件和人类活动.
- 对保存的树进行检查,以寻找燃烧的证据.
主要成果:
- 遗传学记录和PCA表明, *Glyptostrobus pensilis* 对人类的干扰非常敏感.
- 放射性碳测年法显示,森林的灭绝发生在现在之前大约2.1万年,这与温和的气候波动相吻合.
- 在保存的树干上燃烧的证据表明,火是破坏性剂.
- 波亚种和先驱植物的增加,以及金属度的增加,表明征服后的人类活动加剧了 (公元前221年至111年).
结论:
- *Glyptostrobus pensilis*的衰退主要是由人为干扰驱动的,特别是与汉军征服南王国有关的火灾事件.
- 气候变化在全新纪晚期森林破坏中起到了很小的作用.
- 这些发现突显了人类历史活动对古代生态系统和物种生存的影响.
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