Sand beach

They are wonderful

Sand beaches vary

Sand beaches along the Swedish coast can vary in length from only a few metres to several kilometres. Our interpretation of a sand beach is a shallow soft bottom, devoid of vegetation. Differences caused by variations in wave action, tides and the size and composition of the bottom materials that make up the beach create a vast array of beach types. These differences, together with water variations (i.e. salinity), in reality constitute a variety of living environments. Furthermore, the living conditions can vary greatly, even on the "same" beach.

Waves, bottoms and construction

More or less all sand beaches, independent of type, have certain common characteristics. All are composed of bottom material that has been affected and worn by wave action. The waves constantly change the appearance of the beach. The affect the waves have depend on their length, height and frequency. As the waves approach the shoreline, they start colliding and bumping the bottom and therefore slow down. Wave movements can cause an eddying effect and bottom material is whirled up and relocated. (In a new window you can see how waves roll in towards the beach and how sand beaches are built up.)

Sand banks

As the waves slow down they become higher and steeper and as they approach shallow bottom, they break and surf occurs in the so called surf zone. In the surf, the speed of the water towards the shore under the wave peaks is faster than the outgoing under the wave troughs. This action causes a natural sorting of the sand and gravel and can build large and mobile formations such as bars, spits and banks.

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Waves, bottoms and construction

Sand movement and erosion

Sand bottoms as living environments

The art of digging

Sand beach organisms

Food web

Change and variation

Swedish beach life

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Bo Johannesson | Martin Larsvik | Lars-Ove Loo | Helena Samuelsson