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The recent mollusc assemblages of the Vltava River, the longest river in the Czech Republic (430 km), and its valley were studied (South and Central Bohemia). Altogether, 162 species of terrestrial and freshwater molluscs representing 65% of the total Czech malacofauna, were recorded at 532 sites studied between 1940 and 2013. Considering high species richness and diversity of mollusc fauna, the Vltava River valley ranks among the malacologically richest areas in the Czech Republic despite (1) the strong migration barrier of the nine dams on the upper and middle river stretches, (2) the long-term human influence in a whole river valley during the Holocene and, (3) the intensive agriculture in the lower part of the river floodplain. The river phenomenon, partly developed in the upper river stretch and fully developed in the middle part of the river, is the leading cause of such remarkable species richness.

This paper presents a research of floodplain mollusc communities of the Jizera River (the Elbe tributary, North Bohemia, Czech Republic). Altogether, 101 mollusc species (100 species of gastropods, one species of bivalve) were recorded at 55 selected sites during previous and recent researches in 1945–1997 and 2002–2009, representing 40% of the total Czech malacofauna. The upper well-preserved stretch of the river hosts a rich forest mollusc fauna with some rare woodland species e.g. Arion intermedius, Cochlodina dubiosa corcontica, Daudebardia brevipes, D. rufa, Vertigo alpestris and Vitrea subrimata. Impoverish assemblages of the lower stretch are represented by some common or open/semi-open country species, because the river flows there through the landscape of an intensive agricultural land use and high settlement density. Despite, the occurrence of 31 rare species (four of them endangered, eight vulnerable, and 19 near threatened) was recorded at the upper stretch of the Jizera River alluvium, which provides an important refuge for these mollusc faunas.

This paper presents a research of the floodplain mollusc communities of the Ploučnice River (Elbe tributary, North Bohemia, Czech Republic). Altogether, 66 mollusc species (65 species of gastropods, one species of bivalve) were recorded in the 35 floodplain forest sites during the research between 2007 and 2011, representing 27% of the total Czech malacofauna. More than a half of all species represents the common forest species (52% of all recorded species) with some rare woodland species as Aegopinella nitidula, Daudebardia rufa, Macrogastra ventricosa, Oxychilus depressus, O. glaber and two endangered species Clausilia bidentata and Daudebardia brevipes. Rare wetland species protected by the NATURA system Vertigo angustior and vulnerable V. antivertigo were also found. The occurrence of these rare species (two of them endangered, three vulnerable, and 11 near threatened) makes the Ploučnice river alluvium as an important mollusc refugium of prime conservation importance in this fragmented Czech landscape of long-term agricultural land use.

This paper presents a research of floodplain mollusc assemblages of the Úštěcký Brook catchment basin (Elbe tributary, North Bohemia, Czech Republic). Altogether, 71 mollusc species (69 species of Gastropoda, 2 species of Bivalvia) were recorded in the study sites between 2007 and 2011, representing 29% of the total Czech malacofauna. The common forest species dominated (41% of all recorded species) and included some rare woodland species as Daudebardia rufa, Discus perspectivus, Macrogastra ventricosa, and Sphyradium doliolum. Rare wetland species protected by the NATURA system Vertigo angustior and endangered wetland species Vallonia enniensis were also found. The richest assemblages occurred on the upper part of the brook, while the lower part was very species poor due to agriculture land use in this fertile floodplain. A small calcareous moorland, situated in the northeastern vicinity of Úštěk Town (north Bohemia) includes a Holocene mollusc succession that was subdivided into three local mollusc zones: I – basal zone with marked numbers of Discus ruderatus, Vertigo geyeri and numerous aquatic taxa, II – with forest species including Platyla polita and III – dominated by open-ground and catholic species. Despite the specific conditions of the moorland habitat the succession largely corresponds with the standard developmental pattern of the mollusc fauna in the zone of mid-European uplands. Of particular interest is the developmental break reflected by the poor fauna in the layer 3. The malacofauna of the Úštěcký Brook can be used as a model of alluvial mollusc assemblages of the brook floodplain that is situated in the warm area of Central Europe with long-term history of agriculture land use.

The recent molluscan assemblages of all floodplain forests on the 256 km long Ohře River were studied (West and Northwest Bohemia, Czech Republic). Altogether, 75 species of terrestrial Gastropoda representing 30% of the total Czech malacofauna, were recorded at sites selected during previous and recent research from 1950−2010. The Ohře malacofauna is impoverished of many forest and floodplain species in comparison to molluscan assemblages of smaller Bohemian rivers to the west and northwest. The richest molluscan assemblages occur on the upper part of the river, while the middle and lower parts are very poor. Low alpha-diversity of these parts of the Ohře River can be explained by (1) intensive agriculture in floodplain areas of the middle part of the river, (2) the migration barrier of the Nechranice Dam between the upper and middle river parts, and (3) long-term human influence on the lower part of the Ohře River during the Holocene.