Halophytes

Halophytes are plants adapted to saline habitats, able to grow where high salt concentrations would inhibit growth in most other plants. Typical habitats include coastal areas, salt marshes, tidal zones and, more generally, soils with elevated salt content.

The term comes from Greek: hals means salt and phyton means plant. Halophytes do not form a botanical taxonomic group but an ecological category. They belong to a wide range of plant families, yet share comparable adaptations to what is known as salt stress.

This stress arises mainly from two factors: on the one hand, water is often difficult for plants to access in saline soils, and on the other, high concentrations of sodium and chloride ions can disrupt metabolism. Halophytes therefore have specific mechanisms to tolerate, store or excrete salt.

Depending on the degree of adaptation, a distinction is made between obligate halophytes, which occur almost exclusively in saline habitats, and facultative halophytes, which tolerate salt but do not depend on it.

Halophytes are important components of coastal and salt-marsh ecosystems, as they stabilise soils and create habitats for specialised species. Typical examples include glasswort species (Salicornia) and various salt-marsh plants.