Hrabanovská černava (Hrabanov fen) NNR was declared in 1933 on a territory of 27.6 ha and the subject of the protection is the last remnant of fenland formation in the Labe river valley with growths of bog-rushes (Schoenus sp.). The NNR is a part of the proposed Hrabanovská černava Site of Community Importance. The locality lies in a basin near the north-western edge of the town of Lysá nad Labem, in the Středočeský kraj – Central Bohemian Region, at an elevation of 186 metres above sea level. The geological substrate is formed of Mesozoic Cretaceous sediments, which are overlain by various sediments of Pleistocene or Holocene age (sands, moor-like sediments, limey fens and freshwater chalk). Plant remnants and remains of a rich molluscan and ostrocode fauna are found in the clayey freshwater chalk. The area belongs to a warm, slightly dry climatic region with mild winters.
The formation of the fen deposit was depends on the artesian springs, the intensity of which varies over time. This water has high calcium content. Water is one of the most important ecological factors which support the wide variety of communities found in the “černava”. The water regime was interrupted in the 20th century by several drainage programmes.
The largest area in the NNR is vegetated with shrub willow stands and communities of the tufted sedge (Carex elata), which are gradually degraded as they are overgrown by reed (Phragmites australis). These communities occupy the central and western parts of the reserve, which have been left to develop without intervention over the last several decades. Rare species of submerged macrophyte vegetation occur in the pools which, with the exception of the largest one, formed after the extraction of fen peat from the deposit in the past. The common bladderwort (Utricularia vulgaris) has one of its few localities in the Czech Republic here in Hrabanov. The species composition and area covered by the aquatic macrophytes varies over time and at the moment the most common species is the tufted stonewort Chara hispida.
The littoral growths around the largest pool are formed of reed (Phragmites australis) as well as great fen-sedge (Cladium mariscus). This also grows scattered throughout the whole reserve as a part of other communities and this is one of only three recent localities where it grows in the Czech Republic. Hrabanovská černava is the only locality in the Czech Republic where the narrow small-reed (Calamagrostis stricta) currently occurs. In the drier, eastern section of the NNR we can find growths of brown bog-rush (Schoenus ferrugineus), and its hybrids with black bog-rush (Schoenus nigricans). The highest number of endangered species grows on the intermittently wet moor-grass (Molinia) meadows. After cutting was reintroduced here orchids and other rare species are returning. Here we can find relatively strong populations of early marsh orchid (Dactylorhiza incarnata), but also lax-flowered marsh orchid (Orchis palustris). Other notable plant species include military orchid (Orchis militaris), club sedge (Carex buxbaumii), blue moor-grass (Sesleria uliginosa), the rock-cress Arabis nemorensis, blunt-flowered rush (Juncus subnodulosus) and many more.
A wide range of rare animal species are bound to the unique vegetation communities found here in the fen (“černava”). Endangered amphibian species can be found in the pools, including the great crested newt (Triturus cristatus), common spadefoot (Pelobates fuscus) and European fire-bellied toad (Bombina bombina) as well as the rare aquatic gastropod – the peaclam Pisidium pseudosphaerium. Research into the butterflies in the reserve found several species which were first recorded in Bohemia or in the whole Czech Republic: Rebelia herrichiella of the Psychidae, Cosmopterix lienigiella of the Cosmopterigidae, Rhigognostis hufnagelii of the Plutellidae and Stigmella zelleriella the Nepticulidae. Notable bird species which nest in the territory include the snipe (Gallinago gallinago) and the marsh harrier (Circus aeruginosus).
The existence of a fishpond on the Hrabanov territory was documented in the 18th century but it did not remain for long. The fen deposits were cut and extracted by hand in the past. We can still see evidence of this activity today in the form of pools in the western part of the reserve. The meadows growths were probably cut for animal bedding, but only in drier years. During the Second World War the fen was used as a military training area. Agricultural usage came to an end after the Second World War, which led to valuable wetland and meadow communities being overgrown by reeds and shrubs willows.
We are currently planning to extend the NNR to cover the same territory as the proposed Site of Community Importance. In this way valuable moor-grass (Molinia) meadows, xerothermophilous grasslands and sandbanks which currently lie outside the NNR will also gain special protection.