Calcareous grassland (or alkaline grassland) is an

ecosystem An ecosystem (or ecological system) consists of all the organisms and the physical environment with which they interact. These biotic and abiotic components are linked together through nutrient cycles and energy flows. Energy enters the syste ...

associated with thin basic

soil Soil, also commonly referred to as earth or dirt Dirt is an unclean matter, especially when in contact with a person's clothes, skin, or possessions. In such cases, they are said to become dirty. Common types of dirt include: * Debri ...

, such as that on

chalk Chalk is a soft, white, porous, sedimentary carbonate rock. It is a form of limestone composed of the mineral calcite and originally formed deep under the sea by the compression of microscopic plankton that had settled to the sea floor. Ch ...

and

limestone Limestone ( calcium carbonate ) is a type of carbonate sedimentary rock which is the main source of the material lime. It is composed mostly of the minerals calcite and aragonite, which are different crystal forms of . Limestone forms whe ...

downland Downland, chalkland, chalk downs or just downs are areas of open chalk hills, such as the North Downs. This term is used to describe the characteristic landscape in southern England where chalk is exposed at the surface. The name "downs" is deriv ...

. Plants on calcareous grassland are typically short and hardy, and include

grass Poaceae () or Gramineae () is a large and nearly ubiquitous family of monocotyledonous flowering plants commonly known as grasses. It includes the cereal grasses, bamboos and the grasses of natural grassland and species cultivated in lawns a ...

es and herbs such as

clover Clover or trefoil are common names for plants of the genus ''Trifolium'' (from Latin ''tres'' 'three' + ''folium'' 'leaf'), consisting of about 300 species of flowering plants in the legume or pea family Fabaceae originating in Europe. The genus ...

. Calcareous grassland is an important habitat for insects, particularly butterflies and ants, and is kept at a plagioclimax by

grazing In agriculture, grazing is a method of animal husbandry whereby domestic livestock are allowed outdoors to roam around and consume wild vegetations in order to convert the otherwise indigestible (by human gut) cellulose within grass and other ...

animal Animals are multicellular, eukaryotic organisms in the Kingdom (biology), biological kingdom Animalia. With few exceptions, animals Heterotroph, consume organic material, Cellular respiration#Aerobic respiration, breathe oxygen, are Motilit ...

s, usually sheep and sometimes cattle. Rabbits used to play a part but due to the onset of

myxomatosis Myxomatosis is a disease caused by ''Myxoma virus'', a poxvirus in the genus '' Leporipoxvirus''. The natural hosts are tapeti (''Sylvilagus brasiliensis'') in South and Central America, and brush rabbits (''Sylvilagus bachmani'') in North A ...

their numbers decreased so dramatically that they no longer have much of a grazing effect. There are large areas of calcareous grassland in northwestern

Europe Europe is a large peninsula conventionally considered a continent in its own right because of its great physical size and the weight of its history and traditions. Europe is also considered a subcontinent of Eurasia and it is located entirel ...

, particularly areas of southern

England England is a country that is part of the United Kingdom. It shares land borders with Wales to its west and Scotland to its north. The Irish Sea lies northwest and the Celtic Sea to the southwest. It is separated from continental Europe b ...

, such as Salisbury Plain and the

North North is one of the four compass points or cardinal directions. It is the opposite of south and is perpendicular to east and west. ''North'' is a noun, adjective, or adverb indicating direction or geography. Etymology The word ''north ...

and

South Downs The South Downs are a range of chalk hills that extends for about across the south-eastern coastal counties of England from the Itchen valley of Hampshire in the west to Beachy Head, in the Eastbourne Downland Estate, East Sussex, in the eas ...

. The

machair A machair (; sometimes machar in English) is a fertile low-lying grassy plain found on part of the northwest coastlines of Ireland and Scotland, in particular the Outer Hebrides. The best examples are found on North and South Uist, Harri ...

forms a different kind of calcareous grassland, where fertile low-lying plains are formed on ground that is calcium-rich due to shell sand (pulverised

sea shell A seashell or sea shell, also known simply as a shell, is a hard, protective outer layer usually created by an animal or organism that lives in the sea. The shell is part of the body of the animal. Empty seashells are often found washe ...

s).

Notes

References

* Gibson, C.W.D. (1995). Chalk grasslands on former arable land: a review. Bioscan (UK) Ltd, Oxford. * Gibson, C.W.D. & Brown, V.K. (1991). The nature and rate of development of calcareous grassland in southern Britain. Biological Conservation, 58, 297-316. * Hillier, S.H., Walton, D.W.H. & Wells, D.A. (Eds.) (1990). Calcareous grasslands - ecology and management. Bluntisham, Huntingdon. *Mugnai M, Frasconi Wendt C, Balzani P, Ferretti G, Dal Cin M, Masoni A, Frizzi F, Santini G, Viciani D, Foggi B, Lazzaro L. (2021). Small-scale drivers on plant and ant diversity in a grassland habitat through a multifaceted approach. ''PeerJ'' 9:e12517 https://doi.org/10.7717/peerj.12517 * * Smith, C.J. (1980). The Ecology of the English Chalk. Academic Press, London. * * {{Authority control Grasslands Soil Habitats

See also

Notes

References