Aqua means water. Water bodies - big ones like oceans, rivers, lakes and small ones like ponds and your own fish aquarium, come under this category. Many aquatic ecosystems are surrounded by land and the water that they hold is stagnant in nature (e.g. pond). Meanwhile, the water present in the ecosystems such as streams and rivers keeps flowing. The stagnant ones are called Lentic ecosystems and the flowing ones the Lotic ecosystems.
Please watch the videos of various aquatic ecosystems given below
The water present in rivers, streams, inland ponds, dugout wells etc. generally contain very less salt (known as Freshwater ecosystems) compared to the largest aquatic ecosystem - the oceans (Marine Ecosystem)
Aquatic ecosystems
Please watch the videos of various aquatic ecosystems given below