There are two sources of dissolve oxygen into water: the atmosphere as well as from the water plants.
Explanation:
There are two sources of dissolve oxygen into water: the atmosphere as well as from the water plants. Phytoplankton or any submerged plants are the main source of oxygen in a pond. These phytoplankton produce oxygen by process called as photosynthesis in the presence of solar energy and emit this oxygen into the pond
