相关实验视频
Updated: Jul 18, 2025

06:24
Minimal Erythema Dose MED Testing
Published on: May 28, 2013
41.8K
回应评论"在太阳中死去:在波斯纪末期的大规模灭绝中,有直接证据表明紫外线B辐射升高"
Phillip E Jardine1, Huiping Peng2, John E A Marshall3
1Palaeobotany Group, Institute of Geology and Palaeontology, University of Münster, Münster 48149, Germany.
Science advances
|August 25, 2023
概括
这项研究驳斥了质疑在波斯末期大灭绝 (EPME) 期间紫外线辐射增加的证据的说法. 新的分析证实,从这个关键时期的化石花粉中增加了UV-B吸收化合物.
科学领域:
- 古生物学的古生物学
- 地质化学 地质化学
- 大气科学 大气科学
背景情况:
- 珀米纪末期的大规模灭绝 (EPME) 与环境变化有关,包括UV-B流量的潜在增加.
- 之前的研究表明,化石花粉中UV-B吸收化合物 (UAC) 的含量增加是这种变化的证据.
- 最近的批评对UAC数据的方法和解释提出了质疑.
研究的目的:
- 解决和反驳有关EPME化石花粉中UAC测量的具体批评.
- 为了澄清将古代化石花粉与最近的亚化石样本进行比较的有效性.
- 加强EPME期间紫外线B辐射增加的证据.
主要方法:
- 重新评估福里埃变换红外光谱分析 (FTIR) 的化石花粉.
- 对米纪化石花粉和代亚化石花粉之间的比较方法的批评.
- 对光谱数据的潜在干扰的分析,包括水蒸气和二基因产品.
主要成果:
- 珀米亚化石花粉与凯诺纪亚化石花粉FTIR光谱的比较在科学上是无效的.
- 水蒸气波动和代基因产物不能解释EPME期间观察到的UAC峰值.
- 根据UAC水平,EPME期间紫外线B流量增加的证据仍然是强有力的.
结论:
- 关于UAC测量的批评是没有根据的.
- 进一步的研究应侧重于从额外的珀米亚-特里亚斯纪边界段生成形地化学数据.
- 这种方法将提供更全面的证据来测试和确认EPME期间对UV-B流量的发现.
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