Kalníková, V., Palpurina, S., Peterka, T., Kubešová, S., Plesková, Z. & Sabovljević, M. 2017. Bryophytes on river gravel bars in the Balkan mountains: new records and insights into ecology. — Herzogia 30: 370 –386.
Gravel bars are a heterogeneous habitat on the border between the aquatic and terrestrial environments that can maintain a high diversity of bryophyte species. However, the bryoflora of river gravel bar habitats has rarely been explored, particularly in Southeastern Europe. We therefore carried out a two-year field survey on river gravel bars in selected mountains and foothills in the Balkan Peninsula, recording all bryophytes in 4×4 or 3×5 m plots. In total, we sampled 59 vegetation plots on 30 streams and rivers and recorded 85 bryophyte taxa. Here we report Bryum klinggraeffii (a new species for the floras of Albania, Montenegro and Serbia) and five data-deficient or vulnerable species. We found several drought-tolerant bryophytes on gravel bars, e.g. Barbula convoluta, Ceratodon purpureus and Tortella tortuosa, as well as typical hygrophilous species, e.g. Cinclidotus aquaticus, Fontinalis antipyretica and Platyhypnidium riparioides. The most common species in this transitional habitat were Brachythecium rivulare, Bryum argenteum, Oxyrrhynchium hians, Barbula unguiculata, Ceratodon purpureus and Bryum caespiticium. Dentrended correspondence analysis ordination technique identified the complex gradient of moisture and light conditions as the main environmental factor for bryophyte communities on the studied gravel bars.