Marine
Ecosystems: 
Oceans:
The ocean is, geographically, the largest of the world’s ecosystems. There are four major zones that the ocean can be divided into. Each zone has special characteristics such as: water temperature, density, oxygen and the amount of light that reaches it from the surface. These characteristics define the life that is possible within each zone.
The zones are:
- The intertidal zone which is where ocean and land meet. These areas may sometimes be dry and other times be under water.
- The pelagic zone is the open ocean further from land but still on the surface.
- The benthic zone is the area underneath the pelagic zone, where less light penetrates, but does not include the very deepest parts of the ocean.
- The abyssal zone is the deep, dark, formidable ocean far beneath the surface often completely dark.
Coral Reef:
Coral reef is one of the world’s most diverse ecosystems. Some people call it the ocean’s rainforest. The reefs grow in shallow tropical waters and provide food and habitat to a great number of marine species, many of which can only be found here. Many people are dependent on the coral reefs for fishing and the tourism business. The reefs also protect the coastline from erosion as it quells large ocean waves and absorbs the shock. Unfortunately the vulnerable coral reefs are threatened because of pollution, changes in sea temperature, because of climate change, and tourism.
