- Calcicolous grasslands in the British National Vegetation Classification system
This article gives an overview of the
calcicolous grassland communities in theBritish National Vegetation Classification system.Introduction
The calcicolous grassland communities of the NVC were described in Volume 3 of "
British Plant Communities ", first published in 1992, along with the mesotrophic grassland communities and the calcifugous grasslands and montane communities.In total, 14 calcicolous grassland communities have been identified.
All but two of the calcicolous grassland communities fall into two broad groups:
* seven communities which group loosely together under an umbrella of "chalk grassland" and which are found on calcareous soils in the comparatively dry climatic conditions of the lowlands of southern and easternEngland (and also in northern and southern coastal areas ofWales ).
* five upland calcicole communities, distributed in areas of wetter climate through the uplands of Wales, northern England andScotland .The lowlands group comprises two subgroups:
* three short-sward communities associated with heavy grazing: a widespread community (CG2) that is regarded as "typical" chalk grassland, though it also occurs widely on limestone, and its "south-west coastal" (CG1) and "eastern" (CG7) counterparts
* four communities of rank, tussocky grassland associated with low levels of grazing (CG3, CG4, CG5 and CG6)The upland group comprises the following subgroups:
* a widespread short-sward community associated with heavy grazing, CG10
* two localised communities characterised by the presence ofAlpine Lady's-mantle ("Alchemilla alpina"), CG11 and CG12
* two localised communities characterised by the presence ofMountain Avens ("Dryas octopetala"), CG13 and CG14The remaining two communities (CG8 and CG9) are characterised by the presence of
Blue Moor-grass ("Sesleria caerulea"), both of which are localised in northern England and do not fall neatly into either of the two groups described above.List of calcicolous grassland communities
The following is a list of the communities that make up this category:
* CG1 "Festuca ovina - Carlina vulgaris" grassland
* CG2 "Festuca ovina - Avenula pratensis" grassland* CG3 "Bromus erectus" grassland
* CG4 "Brachypodium pinnatum" grassland
* CG5 "Bromus erectus - Brachypodium pinnatum" grassland
* CG6 "Avenula pubescens" grassland
* CG7 "Festuca ovina - Hieracium pilosella - Thymus praecox/pulegioides" grassland
* CG8 "Sesleria albicans - Scabiosa columbaria" grassland
* CG9 "Sesleria albicans - Galium sterneri" grassland
* CG10 "Festuca ovina - Agrostis capillaris - Thymus praecox" grassland
* CG11 "Festuca ovina - Agrostis capillaris - Alchemilla alpina" grass-heath
* CG12 "Festuca ovina - Alchemilla alpina - Silene acaulis" dwarf-herb community
* CG13 "Dryas octopetala - Carex flacca" heath
* CG14 "Dryas octopetala - Silene acaulis" ledge community
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