Question

Brief idea about terrestrial ecosystem and aquatic ecosystem? 

Answer 1

In terrestrial ecosystems, plants provide most of the oxygen and constitute the base of most food webs. 
In aquatic ecosystems (particularly marine) those roles are carried more by various types of algae and plankton.

Answer 2

A terrestrial ecosystem is an ecosystem found only on landforms. Six primary terrestrial ecosystems exist: tundra, taiga, temperate deciduous forest, tropical rain forest, grassland and desert.A community of organisms and their environment that occurs on the land masses of continents and islands. Terrestrial ecosystems are distinguished from aquatic ecosystems by the lower availability of water and the consequent importance of water as a limiting factor. Terrestrial ecosystems are characterized by greater temperature fluctuations on both a diurnal and seasonal basis than occur in aquatic ecosystems in similar climates
An aquatic ecosystem is an ecosystem in a body of water. Communities of organisms that are dependent on each other and on their environment live in aquatic ecosystems. The two main types of aquatic ecosystems aremarine ecosystems and freshwater ecosystems