在中国东北部的南平原,湖泊沉积物磁力记录的环境变化
Huan Fu1, Mingkun Li1, Kunshan Bao1
1School of Geography, South China Normal University, Guangzhou 510631, China.
The Science of the total environment
|February 14, 2024
概括
研究人员在湖泊沉积物中发现了一种新的标记,以确定人类世时代的开始. 南平原湖沉积物中磁石与血的比率可靠地追踪了自大加速以来的人类活动.
科学领域:
- 地球和环境科学 地球和环境科学
- 地质地质地质地质地质地
- 古气候学 古气候学
背景情况:
- 人类世,标志着"伟大的加速",需要全球同步的分层学标记来定义它的开始.
- 湖沉积物的磁性属性是环境变化的敏感指标,对人类世研究有价值.
- 中国东北部的南平原 (SNP) 拥有众多浅湖泊,为恢复人类纪沉积物记录提供了极好的潜力.
研究的目的:
- 调查湖泊沉积物中磁性材料对SNP中人类活动驱动的环境变化的反应.
- 确定可靠的分层学标记,以确定该地区人类世的开始.
- 为了将磁力代理与人类活动指标如GDP和人口相关联.
主要方法:
- 从SNP的五个浅湖的日期的沉积物核心中分析磁性参数.
- 在沉积物中识别和量化磁性矿物质 (磁石和血).
- 磁力代理的相关性,特别是同热残余磁化比 (S-300),与历史的人类活动数据.
主要成果:
- 在湖泊沉积物中,detrital磁和血被确定为主要的磁性矿物.
- 磁性易感度值一般较低,归因于铁磁性矿物质含量低和运输过程.
- 反映了血与磁的比率的S-300比率,在五个湖泊中显示出一致的变化.
- 1950年后,增加的S-300值与人类活动代理 (GDP,人口) 呈正相关,表明磁铁的相对增加.
结论:
- 南平原湖泊沉积物中的S-300比率作为跟踪人类影响和人类新世纪开始的强有力的指标.
- 这种磁力代理提供了对历史当地人类活动的宝贵见解.
- 这些发现提供了潜在的证据,支持基于湖泊沉积物记录的全球同步人类纪定义.
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