Beach Morphology

Beach morphology is all about understanding the shape and form of the beach.

Why is this important?

The shape of a beach determines how much litter will wash up on it and where it settles on the beach. If litter settles on a beach, we say it is deposited on the beach. Where litter is found on the beach can also give information that can help us understand the sources of litter.

Most importantly, it helps to collect the correct data.

The different parts or zones of the beach:

Back of the beach:

The back of the beach is marked by the start of the vegetation, dunes, or sea wall. (as seen in the image). The water line at low tide marks the edge of the water. Between the back of the beach and the edge of the water are two sections, split by the high tide line.

High tide line:

The high tide line is the highest point the water reached during high tide. It may be marked by a visible line of debris (natural and/or man-made litter items that have been pushed up the beach by the waves). Sometimes the foam from the sea leaves a visible line on the sand and this can also be used to determine where the high tide mark is. Below this high tide line, the sand is wet, and above it, the sand is dry.

Supratidal Zone:

The dry sand represents the supratidal zone where the tide has no influence.

Intertidal Zone:

The wet sand below the high tide line, to the water line is the intertidal zone.

When you monitor litter on the beach, , the litter in the intertidal and the supratidal zones will be collected, categorised, and weighed according to the two zones.