The ocean's planktons form the bottom of both the food chain and the bulk of the carbon-oxygen cycle for our planet.

海洋的浮游生物即构成了食物链底端，又是我们地球碳-氧循环的交换场。

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Additionally, the forests of the world are a critical part of the weather cycle as well as the carbon-oxygen cycle.

另外，世界森林是天气循环和碳-氧循环的一个重要组成部分。

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Life in the sea, after all, supports the basic processes that we all take for granted: the water cycle, the oxygen cycle, the carbon cycle, and much more.

CNN: An SOS on World Oceans Day: Save our seas, save ourselves