Aquatic ecosystems 

There are two types of this ecosystem.

Marine ecosystems

There are two types:

According to their distance from the coast: 

Are divided into two zones:

  -Neritic zone: It extends from the shore to the edge of the continental shelf.

  -Oceanic zone: It is in offshore beyond the continental shelf.

According by the depth:

Are divided into three zones:

  -Pelagic zone: Stretches down to 200 metres.

  -Bathyal zone: Range from 200 and 2000 metres.

  -Abyssal zone: Lies below 2000 metres.

Freshwater ecosystems

There are two types:

Lentic ecosystem: 

They are the standing water, and and includes among others the wetlands.

Lotic ecosystem:

They are the flowing water, and includes:

  -Torrents: They are watercourses that have a variable discharge and a short course.

  -Rivers: They are permanent watercourses that run through fixed channels in valleys.