A4 – Euhydrophyte communities of fens:
Floating or shallow rooted aquatic communities of dystrophic and oligotrophic waters. This thermophilous habitat is composed mainly by Hottonia and Aldrovanda. Its actual area is barley 10-11 ha in the country, it is one of the rarest habitats of Hungary. Its stands, usually with smaller than 1 ha extension, occur especially in the western and southern part of Dunántúl (Hanság, along the River Rába, Belső-Somogy, Dráva-sík), on the fenlands of Kiskunság (Turjánvidék and Őrjeg), and in the southern part of Nyírség. Some isolated patches can be found in other regions. As a consequence of drainage and drought periods the area of the habitat has significantly decreased. It is typical that this habitat type was only maintained in the deeper canals. This community is almost missing from the inner part of Alföld (although there are large and well-developed stands on Tiszaalpár).
Molnár, Zs., M. Biró, J. Bölöni & F. Horváth (2008): Distribution of the (semi-)natural habitats in Hungary I.: Marshes and grasslands, Acta Botanica Hungarica 50 (Suppl): 59-105. >>> letöltés (5,4 MB, PDF)