Carmel National Nature Reserve lies close to the village of Carmel in

Carmarthenshire Carmarthenshire ( cy, Sir Gaerfyrddin; or informally ') is a county in the south-west of Wales. The three largest towns are Llanelli, Carmarthen and Ammanford. Carmarthen is the county town and administrative centre. The county is known as ...

. It lies south of

Llandeilo Llandeilo () is a town and community in Carmarthenshire, Wales, situated at the crossing of the River Towy by the A483 on a 19th-century stone bridge. Its population was 1,795 at the 2011 Census. It is adjacent to the westernmost point of the ...

not far from the main road to

Llanelli Llanelli (" St Elli's Parish"; ) is a market town and the largest community in Carmarthenshire and the preserved county of Dyfed, Wales. It is located on the Loughor estuary north-west of Swansea and south-east of the county town, Carmarth ...

. There is a small car park and picnic site for visitors, and footpaths for access. There is an explanatory notice board at the car park. The site is managed by the

Wildlife Trust of South and West Wales The Wildlife Trust of South and West Wales (WTSWW) ( cy, Ymddiriedolaeth Natur De a Gorllewin Cymru) is a Wildlife Trust in south and west Wales, one of 46 such Trusts in the United Kingdom. History Forerunner of the WTSWW, the former West Wal ...

and

Natural Resources Wales Natural Resources Wales ( cy, Cyfoeth Naturiol Cymru) is a Welsh Government sponsored body, which became operational from 1 April 2013, when it took over the management of the natural resources of Wales. It was formed from a merger of the Coun ...

(NRW).

Turlough

Its remarkable

geology Geology () is a branch of natural science concerned with Earth and other astronomical objects, the features or rocks of which it is composed, and the processes by which they change over time. Modern geology significantly overlaps all other Ea ...

is mainly

Carboniferous Limestone Carboniferous Limestone is a collective term for the succession of limestones occurring widely throughout Great Britain and Ireland that were deposited during the Dinantian epoch (geology), Epoch of the Carboniferous period (geology), Period. T ...

, and is the location of a turlough or disappearing lake. They are more frequent in

Ireland Ireland ( ; ga, Éire ; Ulster Scots dialect, Ulster-Scots: ) is an island in the Atlantic Ocean, North Atlantic Ocean, in Northwestern Europe, north-western Europe. It is separated from Great Britain to its east by the North Channel (Grea ...

. The lake fills up in the autumn and winter, being fed only by

groundwater Groundwater is the water present beneath Earth's surface in rock and soil pore spaces and in the fractures of rock formations. About 30 percent of all readily available freshwater in the world is groundwater. A unit of rock or an unconsolidated ...

. The lake disappears by the summer, and is the only known example in

Britain Britain most often refers to: * The United Kingdom, a sovereign state in Europe comprising the island of Great Britain, the north-eastern part of the island of Ireland and many smaller islands * Great Britain, the largest island in the United King ...

. Pant-y-Llyn turlough occupies a small depression on the northern perimeter of the

South Wales Coalfield The South Wales Coalfield ( cy, Maes glo De Cymru) extends across Pembrokeshire, Carmarthenshire, Swansea, Neath Port Talbot, Bridgend, Rhondda Cynon Taf, Merthyr Tydfil, Caerphilly, Blaenau Gwent and Torfaen. It is rich in coal deposits, espe ...

at Cernydd Carmel. This depression represents a

glacial A glacial period (alternatively glacial or glaciation) is an interval of time (thousands of years) within an ice age that is marked by colder temperatures and glacier advances. Interglacials, on the other hand, are periods of warmer climate betwe ...

channel formed along the Betws Fault where displacement has brought Carboniferous Limestone into contact with older impervious Devonian rock. The

hydrological Hydrology () is the scientific study of the movement, distribution, and management of water on Earth and other planets, including the water cycle, water resources, and environmental watershed sustainability. A practitioner of hydrology is calle ...

regime of the waterbody is linked to local groundwater behaviour within the limestone. The basin fills to a depth of about 3 m during late autumn and remains full until the following summer when it empties completely, thus reflecting the characteristic behaviour of turloughs. There are no surface drainage channels and a swallow hole is located at the northern end of the basin. All of the turloughs are found in limestone areas. This is because limestone can be dissolved away by

rain Rain is water droplets that have condensed from atmospheric water vapor and then fall under gravity. Rain is a major component of the water cycle and is responsible for depositing most of the fresh water on the Earth. It provides water ...

water, which becomes mildly acidic by picking up

carbon dioxide Carbon dioxide ( chemical formula ) is a chemical compound made up of molecules that each have one carbon atom covalently double bonded to two oxygen atoms. It is found in the gas state at room temperature. In the air, carbon dioxide is trans ...

as it passes through the atmosphere. The cracks or joints in the rock become widened to such an extent that eventually all of the rain falling on the limestone disappears underground and the water moves through the rock openings ranging from cracks a few millimetres wide to large

cave A cave or cavern is a natural void in the ground, specifically a space large enough for a human to enter. Caves often form by the weathering of rock and often extend deep underground. The word ''cave'' can refer to smaller openings such as sea ...

passages. The limestone is then said to be karstified with many characteristic landscape features.

Flora

Over one hundred species of indigenous woodland plants have been recorded on the site, and a similar number of mosses and other non-vascular plants live there. Some parts of the woodland, which has been in existence since the Middle Ages, are

coppice Coppicing is a traditional method of woodland management which exploits the capacity of many species of trees to put out new shoots from their stump or roots if cut down. In a coppiced wood, which is called a copse, young tree stems are repeate ...

d in order to encourage the growth of wildflowers that need more light, but other parts are managed on a 'minimal intervention' basis and left largely alone. Some rare species found here include mezereon (''Daphne mezereum''),

toothwort Toothwort is a common name for several plants and may refer to: *''Cardamine'', a genus of plants in the mustard family, Brassicaceae *''Lathraea'', a genus of parasitic plants in the family Orobanchaceae Orobanchaceae, the broomrapes, is a fam ...

(''Lathraea squamaria''),

lily-of-the-valley Lily of the valley (''Convallaria majalis'' (), sometimes written lily-of-the-valley, is a woodland flowering plant with sweetly scented, pendent, bell-shaped white flowers borne in sprays in spring. It is native throughout the cool temperate No ...

(''Convallaria majalis'') and herb paris (''Paris quadrifolia'').

Fauna

Frogs, toads and newts breed in the turlough lake and nearby caves are home to bats, including the rare

greater horseshoe bat The greater horseshoe bat (''Rhinolophus ferrumequinum'') is an insectivorous bat of the genus '' Rhinolophus''. Its distribution covers Europe, Northern Africa, Central Asia and Eastern Asia. It is the largest of the horseshoe bats in Europe an ...

(''Rhinolophus ferrumequinium''). Dormice are present in the coppiced woodland. There are several species of butterfly here as well as a great variety of insect life. The soils provide an unusual combination of

habitat In ecology, the term habitat summarises the array of resources, physical and biotic factors that are present in an area, such as to support the survival and reproduction of a particular species. A species habitat can be seen as the physical ...

s to exist side by side, including

ash wood ''Fraxinus'' (), commonly called ash, is a genus of flowering plants in the olive and lilac family, Oleaceae. It contains 45–65 species of usually medium to large trees, mostly deciduous, though a number of subtropical species are evergreen ...

s, species-rich

grassland A grassland is an area where the vegetation is dominated by grasses ( Poaceae). However, sedge ( Cyperaceae) and rush ( Juncaceae) can also be found along with variable proportions of legumes, like clover, and other herbs. Grasslands occur na ...

heathland A heath () is a shrubland habitat found mainly on free-draining infertile, acidic soils and characterised by open, low-growing woody vegetation. Moorland is generally related to high-ground heaths with—especially in Great Britain—a coole ...

and open water. The spring flowers include the primrose or

Primula vulgaris ''Primula vulgaris'', the common primrose, is a species of flowering plant in the family Primulaceae, native to western and southern Europe, northwest Africa, and parts of southwest Asia.''Flora Europaea'Primula vulgaris''/ref> The common name ...

and the

lesser celandine ''Ficaria verna'' (formerly ''Ranunculus ficaria'' ), commonly known as lesser celandine or pilewort, is a low-growing, hairless perennial flowering plant in the buttercup family Ranunculaceae native to Europe and Western Asia. It has fleshy dar ...

. The local landscape is a mix of traditional agriculture and

quarry A quarry is a type of open-pit mine in which dimension stone, rock, construction aggregate, riprap, sand, gravel, or slate is excavated from the ground. The operation of quarries is regulated in some jurisdictions to reduce their envir ...

ing activity, with

ancient woodland In the United Kingdom, an ancient woodland is a woodland that has existed continuously since 1600 or before in England, Wales and Northern Ireland (or 1750 in Scotland). Planting of woodland was uncommon before those dates, so a wood present in 16 ...

s, and

field system The study of field systems (collections of fields) in landscape history is concerned with the size, shape and orientation of a number of fields. These are often adjacent, but may be separated by a later feature. Field systems by region Czech Republ ...

Forestry Forestry is the science and craft of creating, managing, planting, using, conserving and repairing forests, woodlands, and associated resources for human and environmental benefits. Forestry is practiced in plantations and natural stands. ...

is also practised.

Turlough

Flora

Fauna

References

See also