But their Numbers have dwindled since the dawn of the 20th century, with unknown consequences for ocean ecosystems and the planet's carbon cycle.
但自20世纪初以来，它们的数量已逐渐减少，随之而来的是由此对海洋生态系统和全球碳循环产生的未知后果。
Some scientists think that massive ocean extinction events in the past caused Earth's carbon cycle to fluctuate wildly for millions of years afterwards.
一些科学家认为过去大量海洋生物的灭绝，将引起数百万年后地球碳循环上下幅度变大。
The carbon cycle influences the rate at which mountains weather down into seas, the deep circulation of ocean waters helps govern the ebb and flow of ice sheets, and so on.
碳循环影响了山脉夷为海洋的速度，海水深度循环有助于控制冰川消逝和流动，诸如此类。
The export and cycle processes of the riverine carbon are closely related to coastal zone environment, dynamics of the ocean carbon pool and the global climate system.
构成全球碳循环的一个关键环节河流碳的输出及循环过程与近岸水域环境、海洋碳库变动及全球气候系统紧密相关。
On the basis of discussion of present status and problems involved with research on the Marine carbon cycle, the role of Marine ecosystem dynamics in ocean carbon cycle is analysed.
在讨论了目前海洋碳循环研究的现状和存在的问题基础上，分析了海洋生态系统动力学在海洋碳循环中的作用。
On the basis of discussion of present status and problems involved with research on the Marine carbon cycle, the role of Marine ecosystem dynamics in ocean carbon cycle is analysed.
在讨论了目前海洋碳循环研究的现状和存在的问题基础上，分析了海洋生态系统动力学在海洋碳循环中的作用。
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