Dünenketten

Dünenketten are linear belts of sand dunes that run parallel to coastlines. They form a coastal barrier between the sea and inland areas and are built by aeolian processes, with sand transported by onshore winds from beaches and deposited where vegetation begins to stabilize the sand.

Formation and structure

A dune belt typically consists of successive dune ridges of different age and height. The foredunes, closest to the shore, are the first line of defense; behind them rise higher dunes and sometimes dune slacks—low-lying damp depressions between dunes. Pioneer vegetation, especially grasses such as marram grass, stabilizes loose sand and promotes further accretion. Over time, wind, tides, and occasional storms cause ongoing reshaping and occasional landward migration of parts of the belt.

Ecological and protective role

Dünenketten support specialized plant and animal communities adapted to sandy, saline, and harsh conditions. They act as natural buffers against storm surges and coastal erosion, reducing inland flooding and protecting infrastructure and ecosystems behind them. In addition to stabilization, dune systems store sediment and influence local microclimates, providing important habitat for birds, invertebrates, and other wildlife.

Management and threats

Human activities—such as urban development, tourism, and beach recreation—pose risks to dune belts through trampling, stabilization efforts that trap sand, or removal of vegetation. Management strategies include fencing to direct dune formation, revegetation projects, controlled sand nourishment, and access controls to maintain dune integrity. Climate change and sea-level rise increase erosion pressures, prompting adaptive, long-term monitoring and restoration programs.

Examples

Dünenketten are characteristic along many North Sea and Baltic Sea coastlines, including Germany, the Netherlands, and Denmark, where they define a prominent landscape feature and coastal defense system.