An aquatic ecosystem refers to a biological community of organisms and their interactions within a water environment. It encompasses both freshwater and marine ecosystems found in lakes, rivers, oceans, wetlands, and other bodies of water. Aquatic ecosystems consist of diverse habitats, such as coral reefs, estuaries, and freshwater lakes, which support a wide range of plants, animals, and microorganisms. These ecosystems play a crucial role in the biosphere by providing essential services and resources, such as oxygen production, food production, water filtration, and climate regulation.