在ENSO过渡期间的生物圈初级生产
M J Behrenfeld1, J T Randerson, C R McClain
1National Aeronautic and Space Administration, Goddard Space Flight Center, Greenbelt, MD 20771, USA. mjb@neptune.gsfc.nasa.gov
概括
全球海洋和陆地植物生产率 (NPP) 在厄尔尼诺到拉尼诺转移期间进行了比较. 海洋核电站增加,特别是在热带地区,而陆地核电站没有显示出明确的全球ENSO响应.
科学领域:
- 地球科学 地球科学 地球科学
- 海洋学 海洋学 海洋学
- 生态生态学 生态生态学
背景情况:
- 海观宽视场传感器 (SeaWiFS) 提供了关于海洋浮游植物和陆地植物光吸收的关键全球数据.
- 了解海洋和陆地生态系统的净初级生产 (NPP) 对气候建模和生态研究至关重要.
研究的目的:
- 为了比较海洋和陆地生态系统对重大厄尔尼诺到拉尼娜过渡的同时净初级生产 (NPP) 的反应.
- 分析厄尔尼诺-南方振荡 (ENSO) 对全球和区域生物圈生产力的影响.
主要方法:
- 利用SeaWiFS的全球月度测量植物浮游植物菌生物质和陆地植物光收获.
- 分析了1997年9月至2000年8月间的生物圈核电站变化,包括ENSO事件.
主要成果:
- 生物圈核电站的碳含量每年波动6倍,从111到117 Pg C yr−1.1.
- 海洋核电站表现出显著的增长,特别是在受ENSO驱动的上游和营养物质可用性的变化影响的热带地区.
- 全球陆地核电站没有显示出一个一致的ENSO响应,尽管观察到很大的区域差异.
结论:
- 该研究强调了海洋和陆地核电厂对ENSO事件的不同反应.
- 热带海洋对ENSO对生产力的影响比全球陆地生物圈更敏感.
- 对于追踪大规模的环境变化及其对初级生产的影响而言,SeaWiFS数据是非常宝贵的.
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