Summary

Discordant coastline occurs where bands of differing rock type run perpendicular to the coast producing headlands and bays.

Concordant coastlines occur where band of differing rocks run parallel to the coast producing straight coasts or coves and cliffs.

Sand dune coasts occur where there is abundant sand exposed at low tide and a strong onshore prevailing wind.

Specialised plants such as marram grass colonise and anchor the dunes

In quiet coastal environments deposition of fine mud leads to the formation of salt marsh colonised by salt tolerant plants.

Sea levels change long term due to glaciation (isostatic and eustatic changes) and tectonic activity

Coral reefs produce unique maritime habitats which are increasingly in danger from human activity.