Which of the following factors increases the toxicity of heavy metals in aquatic environments?

High water temperature is known to increase the toxicity of heavy metals in aquatic environments due to several physiological and biochemical processes that are influenced by temperature. As the temperature rises, the metabolic rates of aquatic organisms typically increase, leading to greater absorption and accumulation of heavy metals in their tissues. Elevated temperatures can also reduce the solubility of gases, alter water chemistry, and affect the binding of metals to particulates in the water, thereby increasing the bioavailability of these metals to aquatic organisms.

Additionally, warmer waters can create stress conditions for aquatic organisms, further compromising their health and increasing their susceptibility to the harmful effects of heavy metals. This interplay between temperature and metal toxicity is a significant concern in ecological risk assessments and management of aquatic habitats.