Water under higher atmospheric pressure can hold more of which substance?

Water under higher atmospheric pressure can increase the solubility of gases, making it able to hold more dissolved oxygen. This principle is based on Henry's Law, which states that the amount of gas that can dissolve in a liquid is directly proportional to the pressure of the gas above the liquid. As pressure increases, more gas molecules are pushed into the solution, enhancing the water's capacity to hold dissolved oxygen.

In aquatic environments, higher pressures, such as those found in deeper water bodies, can lead to higher concentrations of dissolved oxygen. This phenomenon is crucial for marine life, as many organisms rely on dissolved oxygen for respiration. Increased levels of oxygen can support biodiversity and promote healthier ecosystems.

The other options do not directly relate to the effects of pressure on gas solubility in the same way. Thus, the significance of higher atmospheric pressure is most clearly observed with dissolved oxygen, highlighting its importance in aquatic systems.