The
photic zone is the depth of the
ocean that is exposed to
sunlight. The depth of the photic zone can be greatly affected by such things as
turbidity[?] and the season of the year. The depth of the photic zone is generally proportional to the level of
primary productivity[?] that occurs in that area of the ocean. The
aphotic zone is that portion of the ocean that is exposed to no direct sunlight.
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