Water coming up from below will often have a lower ph than the surface water, because at depth there is no photosynthesis but plenty of respiration.

从地表深层涌出来的水往往比地表水的PH值要低，因为深层除了足够多的呼吸作用外没有任何的光合作用。

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Both the depth and rate of respiration can be adjusted to suit the individual.

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Water coming up from below will often have a lower pH than the surface water, because at depth there is no photosynthesis but plenty of respiration.

ECONOMIST: Ocean acidification