What happens to dissolved oxygen (DO) levels when temperature increases?

When temperature increases, the solubility of oxygen in water decreases, which leads to lower dissolved oxygen (DO) levels. Warmer water holds less oxygen than cooler water because as water temperature rises, the kinetic energy of water molecules also increases. This increased movement causes dissolved gases, such as oxygen, to escape from the water into the atmosphere more readily.

Additionally, higher temperatures can affect the metabolic rates of aquatic organisms, which may increase their demand for oxygen, further contributing to the decline in DO levels. Therefore, understanding the relationship between temperature and dissolved oxygen is crucial in managing aquatic environments, especially for maintaining healthy ecosystems that depend on adequate oxygen levels.

The other options do not accurately reflect the relationship between temperature and dissolved oxygen, as DO levels do not increase with temperature; they typically decline instead.