25/ Sand quarries

Sand quarries are open-pit mines designed to extract sand, from the finest, wind-blown sand to the coarsest river gravel. Mining in aquifers creates water reservoirs, whereas sand quarrys lacking underground seepage are extremely dry. Sand quarries are very valuable for nature conservation. They represent a substitute for sand dunes or alluvial deposits in unregulated river beds, both of which have virtually disappeared in this region. Dry sand quarries where mining has been discontinued are usually reclaimed (filled with soil, reforested); if left to develop naturally, they become overgrown with trees or shrubs. Flooded sand quarries are a popular site for recreational activities, which can disturb vegetation cover and thus delay the loss of valuable treeless habitats.



The fungal community in abandoned sand quarries is closely related to the stage of vegetational development. Among the first fungi to appear in loose vegetation are Omphalina, Psathyrella,, Clitocybe, Psathyrella and Bovista species, as well as rare species such as Pseudoomphalina pachyphylla, the Verdigris Navel (Arrhenia chlorocyanea) or the Moor Club (Clavaria argillacea). With the first woody plants, the number of species, especially mycorrhizal species, increases. First some Thelephora, Laccaria, Inocybe, Hebeloma, Geophora, Rhizopogon, and later also Russula, Tricholoma, Lactarius and Cortinarius species.



Dry sands are typically low in nutrients. Initially, they host annual plants such as Small Sudweed (Filago minima), Field Cudweed (Filago arvensis), Perlwort Spurrey (Spergula morisonii), Rat’s Tail Fescue (Vulpia myuros), Shepherd’s Cress (Teesdalia nudicaulis). Areas in the later development stage tend to develop grasslands with fescues, bentgrass, hawkweed, or heathers as well as various ruderal plants. The natural development of sand areas tends to result in woodlands.

Wetlands are important habitats in sand quarries. Ponds may be inhabited by the Fan-leaved Water-crowfood (Batrachium circinatum), Curled and Broad-leaved Pondweeds (Potamogeton crispus, P. natans), Spiked Water Milfoil (Myriophyllum spicatum). Banks typically host mud-living species, e.g., reeds, bulrushes, sedges, or annual wet sand plants. Exceptionally, the sand quarries may develop into boglands. The rarest wetland plants in the region include Marsh Clubmoss (Lycopodiella inundata) or Round-leaved Sundew (Drosera rotundifolia).



Dry grasslands of sand quarries host many species of animals that used to be abundant in our region in the past, but have been declining due to human activities (e.g. oil beetles, tiger beetles). Sandy areas are also important for reptiles, especially the Sand Lizard (Lacerta agillis). They also provide a suitable nesting environment for birds such as the Sand Martin (Riparia riparia) and the Woodlark (Lullula arborea). Wet sand quarries host a number of invertebrate species, such as dragonflies or Donacia beetles, that are associated with aquatic or wetland vegetation. The unvegetated banks and beaches in sand quarries are inhabited by numerous species of ground beetles. Pools serve as breeding areas for amphibians, e.g., the European Green Toad (Bufotes viridis) and the Natterjack Toad (Epidalea calamita). Some reptiles also occur in this environment, e.g., the Grass Snake (Natrix natrix). Large water bodies are important as breeding or congregation sites for waterbirds, e.g., the Great Crested Grebe (Podiceps cristatus).



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