Sand beach

They are wonderful

Beaches that are composed of large sand grains with a low organic content, are exposed to powerful wave action and are well drained and oxygenated. Here, animals can live in the bottom sediment. Beaches that are more protected from wave action, have finer sand grains with more organic material, exhibit powerful chemical reactions when the bottom sediment is disturbed. Most organisms that live here, do so in the shallow, oxygenated layer near the bottom sediment. (More about oxygen deficiency later)
    Sediment particle size and form are of importance because they affect the size of the space between the particles. These spaces constitute the living-space for many microscopic organisms. Particle size also affects the water content and flow through the sediment, aswell as oxygenation. Water content is an important factor, as it affects how easily organisms can dig down into the sediment, degree of oxygenation. and the sediments ability to protect organisms from dessication and extreme temperatures.

Sand beaches are difficult to live on

There are many reasons why a sand beach can be an arduous living environment. Fluctuations in sea level cause intense variations in desication and temperature, especially in the upper reaches. Other difficulties are variations in saline content as a result of rain, floods and drought, and the transplantation of the whole living environment due to storms.

Variations on different levels without noticable boundaries

It is important to remember that all these natural environmental factors are often very gradual and extend from different natural extremities, and that transitions can take place over both short and longer distances.    


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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