The ecological role of nutrient input from rivers to coastal ecosystems is significant, as these nutrients support productivity and biodiversity in marine environments. Rivers transport essential elements like nitrogen and phosphorus, which are critical for the growth of phytoplankton, the base of aquatic food webs. Enhanced nutrient availability can boost fish populations and overall ecosystem health. However, excessive nutrient runoff can lead to harmful algal blooms, underscoring the need for careful management of land use practices to maintain balanced nutrient inputs and protect coastal habitats.