Final answer:
Human activity can impact freshwater resources in several ways, including through the release of nitrogen and phosphorus compounds from fertilizers, the excretion of drugs by humans, and heat pollution from industrial processes. These activities can lead to eutrophication, harm aquatic organisms, and disrupt the balance of aquatic ecosystems.
Step-by-step explanation:
Human activity can have significant effects on freshwater resources. One major impact is the release of nitrogen and phosphorus compounds from artificial fertilizers into lakes, rivers, and streams through surface runoff. This can lead to eutrophication, where excessive nutrient runoff causes the overgrowth of algae, depleting oxygen levels in the water and harming aquatic organisms.
In addition, drugs excreted by humans can enter aquatic ecosystems through wastewater and affect aquatic organisms. These drugs can have various negative effects, such as disrupting hormone balances or impairing reproduction and development in aquatic organisms.
Furthermore, heat pollution, also known as thermal pollution, can occur when industrial processes or power plants release heated water into rivers or lakes. This increase in water temperature can have detrimental effects on aquatic ecosystems, including reduced oxygen levels, changes in species composition, and the disruption of spawning and migration patterns.