What environmental factor can significantly impact the distribution of aquatic organisms?

Water temperature and salinity are critical environmental factors that significantly impact the distribution of aquatic organisms. The temperature of water affects the metabolic rates of organisms, influencing their growth, reproduction, and survival. Many aquatic species thrive within specific temperature ranges, and variations can lead to stress or mortality.

Salinity also plays a crucial role, particularly in estuarine and coastal ecosystems where freshwater mixes with saltwater. Different organisms have varying tolerances to salinity levels, which can dictate where they are found. For instance, certain fish and invertebrate species may only survive in brackish waters, while others require fully saline conditions or freshwater environments.

Together, water temperature and salinity create a dynamic habitat that shapes the biodiversity of aquatic systems, determining which species can thrive or be excluded from specific areas based on their physiological tolerances and ecological needs.