在亚热带海洋中氧气的净产量
Stephen C Riser1, Kenneth S Johnson
1School of Oceanography, University of Washington, Seattle, Washington 98195, USA. riser@ocean.washington.edu
Nature
|January 19, 2008
概括
低营养地区的海洋浮游生物是氧气和碳的净生产者. 低于冬季混合事件的持续氧气增加显示出一致的净自,挑战了情节性生产理论.
科学领域:
- 海洋学 海洋学 海洋学
- 海洋生态海洋生态学
- 生物地质化学生物地质化学
背景情况:
- 低营养的海洋地区占全球海洋表面的80%.
- 浮游生物社区在氧气和碳循环中的作用是不确定的.
- 瓶子实验 (净消费) 和地球化学数据 (净产量) 之间存在相互矛盾的证据.
研究的目的:
- 为了研究亚热带旋转中的净氧气和碳平衡.
- 解决直接测量和地化学证据之间的差异.
- 评估情节性与连续性初级生产的作用.
主要方法:
- 在三年内部署氧气传感器在造型浮标上.
- 监测北太平洋和南太平洋亚热带旋转的氧气度.
- 与水柱混合和社区生产相关的氧气动态分析.
主要成果:
- 冬季的混合事件使上层水柱均化,导致低氧.
- 在混合层下方观察到持续的,几乎恒定的氧气增加率.
- 这个比率与社区净生产的独立指标相一致.
结论:
- 亚热带旋转生态系统是全年固定碳的净生产者 (净自营).
- 持续的生产,而不是偶尔的事件,维持正氧生产.
- 这些发现支持在这些广的海洋区域中保持一致的净自营养状态.
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