trophogenic zone

The trophogenic zone is the upper layer of a lake or ocean where inorganic matter is converted into organic matter through photosynthesis. This zone is also known as the photic zone or euphotic zone, referring to the area that receives sufficient sunlight to support photosynthesis by phytoplankton and plants.12

In marine ecosystems, primary productivity, the rate at which energy is converted into organic substances, occurs in the photic zone. Phytoplankton are the primary producers, utilizing sunlight, carbon dioxide, nitrogen, and phosphorus. The amount of light and nutrient availability significantly influence the rate of production. This zone is crucial for supporting the entire marine food web, as the organic material produced is available to consumers.34