Vegetation of the Czech Republic
Isoëtetum echinosporae Koch ex Oberdorfer 1957
This association is represented by a single monospecific stand of Isoëtes echinospora on the bottom of Plešné Lake at an altitude of 1087 m in the Šumava Mountains. It occurs mainly at depths of 30–50 cm, rarely up to 75 cm. The lake is situated on granite bedrock and its water is mesotrophic. Due to acid rain, lake water has not exceeded pH 5 since the 1960s, which has caused an increase in toxic aluminium concentrations and restricted regeneration of Isoëtes. However, in recent years water chemistry has improved and regeneration of Isoëtes resumed after 2005.
Nomen mutatum propositum
Orig. (Oberdorfer 1957): Isoëtetum tenellae W. Koch 26 (Isoëtes tenella = I. echinospora)
Syn.: Isoëtetum echinosporae Koch 1926 (§ 2b, nomen nudum)
Diagnostic species: Isoëtes echinospora
Constant species: Isoëtes echinospora
Dominant species: –
Formal definition: Isoëtes echinospora cover > 5 %
Source: Čtvrtlíková M. (2011): VDA01 Isoëtetum echinosporae Koch ex Oberdorfer 1957. In: Chytrý M. (ed.), Vegetace České republiky. 3. Vodní a mokřadní vegetace [Vegetation of the Czech Republic 3. Aquatic and wetland vegetation]. Academia, Praha, pp. 271-273.