Alisma wahlenbergii

A potential threat to the species is eutrophication as the species needs nutrient rich but clear water. The sources of the water pollution are various and can include sewage from urban areas. Further threats in Russia are industrial constructions such as dykes and hydraulic soil deposition as well as recreational activities.

In Finland, the species is furthermore threatened by overgrowing of coastal meadows and open coastal habitats (due to cessation of grazing and due to increase of reed beds), and construction of waterways (embankments, digging ways for boats etc.) (Rassi et al. 2010). Those threats and eutrophication caused the disappearance of the populations on the Finnish side of the Finnish Gulf.

A. wahlenbergii is listed as a priority species on Annex II of the Habitats Directive. It is classed as Endangered B2ab(iv,v) in Sweden and protected by law and included in the Russian Red Data Book as Critically Endangered (which shows only four sites). In Finland, it is listed as Endangered B2b(iii)c(iv) (Rassi et al. 2010) and it is protected and named as a species under strict protection in national legislation. In Finland, c. 40% of the sites are situated in Natura 2000 areas.

For Russia, control of water pollution is urgently recommended.

Some localities are included in a marine national park in Sweden. In Russia, the subpopulations are included in a protected area in the Finnish Gulf but the level of this protection is unclear.