Only the adults survive A long-term resistance of Isoetes lacustris to acidity and aluminium toxicity stress in a Bohemian Forest lake

0524288 - BC 2021 RIV NL eng J - Journal Article
Čtvrtlíková, Martina - Kopáček, Jiří - Nedoma, Jiří - Znachor, Petr - Vrba, Jaroslav
Only the adults survive A long-term resistance of Isoetes lacustris to acidity and aluminium toxicity stress in a Bohemian Forest lake.
Ecological Indicators. Roč. 111, APR 2020 (2020), č. článku 106026. ISSN 1470-160X. E-ISSN 1872-7034
R&D Projects: GA MŠMT(CZ) EE2.3.30.0032; GA ČR(CZ) GA19-16605S
Institutional support: RVO:60077344
Keywords : Acidification * Isoetid * Reproduction * Toxicity * Metal bioaccumulation * Epifluorescence image analysis
OECD category: Ecology
Impact factor: 4.958, year: 2020
Method of publishing: Limited access
https://www.sciencedirect.com/science/article/pii/S1470160X19310222?via%3Dihub

The aquatic quillwort Isoetes lacustris L. survived five decades of severe acidification in Cerne Lake (Bohemian Forest, central Europe), but failed to reproduce. To detect which ontogenetic stage is more affected by water acidification and to identify water chemistry thresholds for successful recruitment, experiments were carried out on quillwort sporelings grown in the laboratory, using different pH (4-8) and aluminium (Al) concentrations (0-1000 mu g/L). Growth-related symptoms and Al accumulations in tissues were compared with those observed in sporelings collected in the lake. In the laboratory, the threshold Al concentrations >= 100 mu g/L and pH <= 5.0 reduced absorptive organs (macrogametophyte rhizoids, roots, and root hairs), so that the ratio of below-ground to above-ground sporeling biomass decreased to <1. Nonetheless, stimulatory growth was demonstrated that affected the dose-response relationships of both absorptive and assimilative organs as well as sporeling growth restoration. The sporelings exposed to Al concentrations >= 100 mu g/L accumulated high amounts of Al in their macrogametophytes and roots, but not in leaves. The lake sporelings had markedly longer roots, lower Al accumulations, but more reduced rhizoids and root hairs than those at 100 mu g/L of Al in the laboratory. Even though water acidification was harmful to the shallow-rooted early ontogenetic stages, the in situ population survived due to the resistance and long life span of the deep-rooted adults. The effects of water acidification on sympatric congeneric quillworts as well as the other isoetids and competitive macrophytes in acid-sensitive softwater lakes are discussed, taking into account the influence of exposure to threshold acidity and Al toxicity and also the likelihood of such exposure.
Permanent Link: http://hdl.handle.net/11104/0308658