disphotic zone

oceanography

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June 25, 2026

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The disphotic zone is a layer within the ocean's photic zone where sunlight penetrates but is insufficient for photosynthesis. This zone extends from the base of the euphotic zone (where photosynthesis occurs) down to about 200 meters. While light is present, the rate of respiration exceeds photosynthesis in this region. The depth of the disphotic zone can vary based on factors like cloud cover, water turbidity, and ocean surface conditions. Organisms in this zone may migrate to the photic zone at night, while others are adapted to live permanently in darkness.12

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marine ecosystem
Geography, oceanography, and topography
…are distinguished the euphotic and disphotic zones. The euphotic zone is the layer closer to the surface that receives enough light for photosynthesis to occur. Beneath lies the disphotic zone, which is illuminated but so poorly that rates of respiration exceed those of photosynthesis. The actual depth of these zones…
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…are distinguished the euphotic and disphotic zones. The euphotic zone is the layer closer to the surface that receives enough light for photosynthesis to occur. Beneath lies the disphotic zone, which is illuminated but so poorly that rates of respiration exceed those of photosynthesis. The actual depth of these zones…
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photic zone
…insufficient for photosynthesis illuminates the disphotic zone, which extends from the base of the euphotic zone to about 200 m. The thicknesses of the photic and euphotic zones vary with the intensity of sunlight as a function of season and latitude and with the degree of water turbidity. The bottommost,…
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…insufficient for photosynthesis illuminates the disphotic zone, which extends from the base of the euphotic zone to about 200 m. The thicknesses of the photic and euphotic zones vary with the intensity of sunlight as a function of season and latitude and with the degree of water turbidity. The bottommost,…
Read More