| This illuminated surface layer is called the euphotic zone, and all of the ocean's primary production occurs there. |
| Therefore the physical nutrient supply in the euphotic zone is a measure of the impact of the physical mechanisms on the primary production. |
| Indeed, the MLD maximum, usually reached in late winter determines the annual nutrient reloading of the euphotic zone. |
| The euphotic zone is the layer closer to the surface that receives enough light for photosynthesis to occur. |
| The deeper waters are a reservoir of nutrients, and the primary supply pathway for the euphotic zone. |
| The euphotic zone extends from the surface down to the maximum depth at which photosynthetic plants can grow. |
