当浮游植物死后沉到海底，细菌开始将其分解。

When the plants die, they sink to the ocean floor where bacteria begin to break them down.

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但化学品不易分解，所以他们仍然环绕在海洋里，并以他们的方式影响海底生物，那里的片脚类动物是以他们为食的。

But they don't break down easily, so they're still swirling around in the oceans and working their way down to the seafloor, where amphipods gobble them up.

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死去的动植物的残骸沉落海底，被沉积物掩埋，并在数百万年后分解成甲烷。

Detritus from dead plants and animals that settled to the bottom was buried by sediment and broke down into methane after million of years.

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