Which factors can influence the distribution of freshwater organisms?

The factors that influence the distribution of freshwater organisms are crucial for understanding their habitats and ecological roles. Water temperature, pH, oxygen levels, and nutrient availability are all essential parameters that vary in freshwater environments and directly affect the survival, growth, and reproduction of aquatic organisms.

Temperature impacts metabolic rates and can determine species composition within a water body. For instance, colder waters may host different species compared to warmer waters. pH levels are vital because they affect the solubility of nutrients and toxins, influencing what organisms can thrive. Oxygen levels are critical for respiration in fish and many invertebrates; low oxygen can limit the types of species present. Nutrient availability, such as phosphorus and nitrogen, is important for primary producers like algae, which in turn support higher trophic levels in aquatic ecosystems.

In comparison, while soil texture and sunlight availability can influence certain aspects of freshwater ecosystems, they do not encompass the critical biochemical factors that are more directly linked to organism health and distribution. Wind speed and atmospheric pressure have a much lesser impact on freshwater species compared to the parameters listed in the correct answer, since these factors are more relevant to terrestrial ecosystems and broader climatic conditions. Lastly, limiting the influential factors to only water temperature and light exposure overlooks other vital elements