概括
大西洋养分线深度的气候控制与植物浮游生物 Florisphaera profunda.有关. 它的丰富度变化与营养线深度变化相关,受千年的轨道阳光和热带东风的影响.
科学领域:
- 古海洋学是古海洋学.
- 海洋浮游植物生态学海洋浮游植物生态学
- 气候动力学 气候动力学
背景情况:
- 在赤道大西洋的营养线深度影响海洋生态系统.
- Florisphaera profunda的丰富性是营养线深度的潜在指标.
- 之前的研究表明,气候和营养素的变化之间存在联系.
研究的目的:
- 为了研究Florisphaera profunda丰富度和营养线深度之间的长期关系.
- 为了确定轨道阳光照射对大西洋气候和营养线动态的影响.
- 为了重建赤道大西洋过去的气候变化.
主要方法:
- 对长达20万年的深海核心记录F. profunda相对丰度的分析.
- 交叉光谱分析与来自动物浮游生物物种的海面温度数据.
- F. profunda周期与地球轨道的 precessional 周期的相关性.
主要成果:
- 一个20万年的记录显示F. profunda变异以23000年的 precessional带为中心.
- F. profunda的周期是连贯的,并且与海面温度周期相一致.
- 丰度变化与周日时间 (十二月和六月) 相对应.
结论:
- 在赤道大西洋的营养线深度是由热带东方的变化控制的.
- 这些变化是由轨道阳光照射的 precessional 组成部分强迫的.
- 营养线深度的气候控制在超过1万年的时间尺度上运行.
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