Which process describes how aquatic plants contribute to oxygen levels in water?

The process by which aquatic plants contribute to oxygen levels in water is photosynthesis. During photosynthesis, plants use sunlight, carbon dioxide from the water, and nutrients to produce glucose and oxygen. This process occurs primarily in the presence of light and involves chlorophyll, which captures sunlight. As a byproduct of photosynthesis, oxygen is released into the surrounding water, significantly enhancing the oxygen content which is crucial for the survival of aquatic organisms.

In contrast, respiration, while it also involves the exchange of gases, consumes oxygen and releases carbon dioxide, playing a different role in the aquatic ecosystem. Evaporation pertains to the process where liquid water turns into vapor and does not directly involve oxygen production. Transpiration involves the release of water vapor from plant surfaces but does not contribute to oxygen levels. Hence, photosynthesis is the key process that fortifies aquatic environments with essential oxygen.