Kystduner

Kystduner are dune ecosystems found along coastlines, formed by wind-blown sand that accumulates into ridges and depressions adjacent to beaches. They act as natural barriers against storm surge and salt spray, helping protect inland areas while supporting unique plant and animal communities. In many Nordic and Baltic contexts the term kystduner specifically refers to these dynamic dune systems along the seashore.

Formation and structure occur where sand supplied by the beach is mobilized by wind. Early, or embryo, dunes develop as vegetation begins to trap sand. Over time, foredunes rise and stabilize with hardy dune grasses, commonly marram grass (Ammophila arenaria) in European settings, along with other grasses, shrubs, and lichens. The system may include dune slacks, wet depressions that host specialized plants and invertebrates, and mobile zones that continue to shift with weather patterns and sea level.

Ecology within kystduner is characterized by spatial and successional diversity. The vegetation gradually forestalls sand movement, creating habitats for endemic flora and fauna adapted to sandy, coastal conditions. These ecosystems support nesting birds, invertebrates, and a range of alpine- and temperate-zone species in different regions.

Threats to kystduner include coastal development, trampling by hikers, sand extraction, invasive species, and accelerated sea-level rise. Management typically emphasizes protection of dune cores, restoration of natural dynamics, and controlled access. Restoration measures may involve fencing to reduce disturbance, re-vegetation with native dune species, and dune nourishment or reengineering to restore elevation and continuity.

See also: coastal ecosystems, dune stabilization, coastal management.