Mediterranean and Black Sea moist and wet dune slack

This habitat type develops in small permanent or temporary fresh water bodies in the depressions between dune ridges of the Mediterranean and Black Sea coasts. These wetlands occur at the lower parts of white and grey dune systems, having a patchy distribution. Coastal dune slacks are more common along the Atlantic coasts as in the warmer Mediterranean and Black Sea coasts .Plant communities in wet dune slacks depend on the groundwater level. This varies spatially and temporally and dune slacks may occur in a range from permanent water bodies to waterlogged or moist sandy depressions.

The communities consist of typical hydro- or hygrophytic species. The permanent or semi-permanent (persisting until summer) water bodies, like small ponds, lakes and pools, are inhabited by aquatic vegetation, with species of the classes Potametea or Charetea. Often a zone of high grasses (reed, sedges, rushes, reed mace) develops at their periphery. Nutrient content also varies, but mostly the water is eutrophic to mesotrophic, sometimes even dystrophic. Temporary water bodies are very diverse in water depth and duration of water retention. Stands of high helophytes, like Phragmites australis, Typha spp., Juncus spp., Carex spp. Cladium mariscus, Holoschoenus spp. and Scirpus spp. develop mostly on the over-wet sands, which desiccate during the summer. In such conditions, a slight salinization is possible, and halophytic species or small therophytes of the class Isoeto-Nanojuncetea may inhabit the bare bottoms. Such dune slacks are species rich and highly specialised habitats, and they are threatened by the lowering of water table.

Indicators of quality:

The habitat is very sensitive to every human disturbance, resulting from tourism development, physical damage, eutrophication, over growth through lack of grazing, climate change and especially changes in the water regime. The most important indicators of good quality are:

• natural water regime
• balance between the hygrophytic and hydrophytic vegetation
• diversity of plant communities depending on water dynamic
• occurrence of a range of different dune slacks within dune systems at a landscape level

Synthesis of Red List assessment

Confidence in the assessment

Pressures and threats