在沿海入口处观察生物产生的流
Eric Kunze1, John F Dower, Ian Beveridge
1School of Earth and Ocean Sciences, University of Victoria, Post Office Box 3055, STN CSC Victoria, BC, V8W-3P6, Canada. kunze@uvic.ca
Science (New York, N.Y.)
|September 23, 2006
概括
的垂直迁徙大大增加了黄昏时的海洋动荡,增加了每天的混合100倍. 这种生物产生的流影响了海洋水中的营养物质运输和气体交换.
科学领域:
- 海洋生物学 海洋生物学
- 海洋学 海洋学 海洋学
- 流体动力学 流体动力学
背景情况:
- 动物浮游生物的垂直迁移,如鱼,是海洋生态系统中常见的现象.
- 生物的运动可以影响物理海洋学过程,包括混合和运输.
- 了解生物产生的流对于海洋生态系统动态至关重要.
研究的目的:
- 为了量化一个密集的鱼层在黄昏上升时产生的流.
- 评估生物产生的流对沿海入口的每日混合的影响.
- 探索生物流对海洋营养循环和气体交换的更广泛影响.
主要方法:
- 在沿海入口的流现场测量.
- 声学分散层检测以确定鱼生物质和密度.
- 在白天和黄昏期间的流水平的比较.
主要成果:
- 与白天相比,岩层在黄昏上升期间的流水平比白天高出三到四个数量级.
- 由于的迁移,入口的每日平均混合量增加了100倍.
- 密集的鱼层的黄昏上升显著放大了物理混合过程.
结论:
- 来自迁徙动物浮游生物的生物产生的流可以显著增强海洋的垂直混合.
- 这种增强的混合会影响营养物质的运输到地表水中,从而可能提高生物生产力.
- 由生物驱动的流影响了海洋内部和大气之间的二氧化碳等气体交换.
相关概念视频
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