Lesson 1 - Life at the Coast

by Alan Deidun

 
 

 
Coastal Habitats

Many different types of habitats and animal and plant species are found at the coast. Examples of coastal habitats include sandy beaches and dunes, shingle (pebbly) beaches, rocky shores, marshlands, lagoons, mudflats, cliffs, clay slopes, estuaries, mangroves, cliffs, etc.

The beach is that stretch of shore between the high and low water lines that is covered by sand or some other unconsolidated material. Shingle (pebbly) beaches are covered with coarse stones and pebbles and usually have a steep slope.

Coastal dunes are those hills or ridges found at the back of the beach. They are made of wind-blown sand and are usually covered with grasses.

Rocky shores are the intertidal area on the coast that is made of solid rock.
Marshlands are low-lying wetlands covered with grassy vegetation. These are usually found in the transition zone between land and water.

Lagoons are areas of shallow water that are usually separated from the sea by coral reefs or sandbars.

Mud flats are low-lying muddy areas on the seaward side of the coast. They are found in sheltered waters and are covered at high tide and exposed during low tide.
Estuaries form at the mouth of a river, at the point where it opens into the sea (e.g. where the Nile River in Egypt opens into the Mediterranean Sea). Estuaries transport with them large quantities of sediments, which may accumulate and be compacted into a landform, known as a river delta. The water in an estuary is described as being brackish - i.e. it is not freshwater but is not as salty as the sea. As a result, estuaries support some unique organisms.

Where the coast is characterized by sheer cliffs, there is no direct access from the land to the sea � the chalk cliffs of Dover in England are amongst the most well-known around the world

Mangroves are trees and shrubs that grow in saline coastal habitats in the tropics (close to the equator) and subtropics.