The ecological impact of saltwater intrusion on coastal areas primarily involves the degradation of freshwater ecosystems and alterations in species composition. As sea levels rise due to climate change, saltwater infiltrates aquifers and estuaries, compromising water quality and affecting the flora and fauna adapted to freshwater environments. This intrusion can lead to declines in wetlands, disruption of habitat for freshwater species, and changes in nutrient cycling. Managing saltwater intrusion is vital to protect coastal ecosystems and maintain biodiversity.