Carmel National Nature Reserve lies close to the village of

Carmel Carmel may refer to: * Carmel (biblical settlement), an ancient Israelite town in Judea * Mount Carmel, a coastal mountain range in Israel overlooking the Mediterranean Sea * Carmelites, a Roman Catholic mendicant religious order Carmel may also ...

Carmarthenshire Carmarthenshire (; or informally ') is a Principal areas of Wales, county in the South West Wales, south-west of Wales. The three largest towns are Llanelli, Carmarthen and Ammanford. Carmarthen is the county town and administrative centre. ...

. It lies south of

Llandeilo Llandeilo () is a town and Community (Wales), community in Carmarthenshire, Wales, situated where the River Towy is crossed by the A483 road, A483 on a 19th-century stone bridge. At the 2021 United Kingdom census, 2021 census the community had ...

not far from the main road to

Llanelli ; ) is a market town and community (Wales), community in Carmarthenshire and the Preserved counties of Wales, preserved county of Dyfed, Wales. It is on the estuary of the River Loughor and is the largest town in the Principal areas of Wales, ...

. 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) () 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 Wales Naturalists' Trust traces its origin to a me ...

and

Natural Resources Wales Natural Resources Wales () 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 Countryside Council for Wales, E ...

(NRW).

Turlough

Its remarkable

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

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

Ireland Ireland (, ; ; Ulster Scots dialect, Ulster-Scots: ) is an island in the North Atlantic Ocean, in Northwestern Europe. Geopolitically, the island is divided between the Republic of Ireland (officially Names of the Irish state, named Irelan ...

. 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 Pore space in soil, soil pore spaces and in the fractures of stratum, rock formations. About 30 percent of all readily available fresh water in the world is groundwater. A unit ...

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

Britain Britain most often refers to: * Great Britain, a large island comprising the countries of England, Scotland and Wales * The United Kingdom of Great Britain and Northern Ireland, a sovereign state in Europe comprising Great Britain and the north-eas ...

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

South Wales Coalfield The South Wales Coalfield () 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, especially in the South Wales ...

at Cernydd Carmel. This depression represents a

glacial A glacier (; or ) is a persistent body of dense ice, a form of rock, that is constantly moving downhill under its own weight. A glacier forms where the accumulation of snow exceeds its ablation over many years, often centuries. It acquires ...

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

Devonian The Devonian ( ) is a period (geology), geologic period and system (stratigraphy), system of the Paleozoic era (geology), era during the Phanerozoic eon (geology), eon, spanning 60.3 million years from the end of the preceding Silurian per ...

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 drainage basin sustainability. A practitioner of hydrology is called a hydro ...

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 A sinkhole is a depression or hole in the ground caused by some form of collapse of the surface layer. The term is sometimes used to refer to doline, enclosed depressions that are also known as shakeholes, and to openings where surface water ...

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 a form of precipitation where water drop (liquid), droplets that have condensation, condensed from Water vapor#In Earth's atmosphere, atmospheric water vapor fall under gravity. Rain is a major component of the water cycle and is res ...

water, which becomes mildly

acid An acid is a molecule or ion capable of either donating a proton (i.e. Hydron, hydrogen cation, H+), known as a Brønsted–Lowry acid–base theory, Brønsted–Lowry acid, or forming a covalent bond with an electron pair, known as a Lewis ...

ic by picking up

carbon dioxide Carbon dioxide is a chemical compound with the chemical formula . It is made up of molecules that each have one carbon atom covalent bond, covalently double bonded to two oxygen atoms. It is found in a gas state at room temperature and at norma ...

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 Caves or caverns are natural voids under the Earth's Planetary surface, surface. Caves often form by the weathering of rock and often extend deep underground. Exogene caves are smaller openings that extend a relatively short distance undergrou ...

passages. The limestone is then said to be

karst Karst () is a topography formed from the dissolution of soluble carbonate rocks such as limestone and Dolomite (rock), dolomite. It is characterized by features like poljes above and drainage systems with sinkholes and caves underground. Ther ...

ified 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 the traditional method in woodland management of cutting down a tree to a tree stump, stump, which in many species encourages new Shoot (botany), shoots to grow from the stump or roots, thus ultimately regrowing the tree. A forest ...

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'', commonly known as mezereum, mezereon, February daphne, spurge laurel or spurge olive, is a species of ''Daphne'' in the flowering plant family Thymelaeaceae, native to most of Europe and Western Asia, north to northern Scand ...

(''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 fa ...

(''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'', the herb Paris or true lover's knot, is a species of flowering plant in the family Melanthiaceae. It occurs in temperate and cool areas throughout Eurasia, from Spain to Yakutia, and from Iceland to Mongolia. It prefers ...

(''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 Insectivore, 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 i ...

(''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, habitat refers to the array of resources, 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 manifestation of its ...

s to exist side by side, including

ash wood ''Fraxinus'' (), commonly called ash, is a genus of plants in the olive and lilac family, Oleaceae, and comprises 45–65 species of usually medium-to-large trees, most of which are deciduous trees, although some subtropical species are evergr ...

s, species-rich

grassland A grassland is an area where the vegetation is dominance (ecology), dominated by grasses (Poaceae). However, sedge (Cyperaceae) and rush (Juncaceae) can also be found along with variable proportions of legumes such as clover, and other Herbaceo ...

heathland A heath () is a shrubland habitat found mainly on free-draining infertile, acidic soils and is 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'', also called the common primrose, is a species of flowering plant in the family (biology), family Primulaceae, native plant, native to Eurasia.''Flora Europaea'Primula vulgaris''/ref> The common name of this plant is prim ...

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. It has fleshy dark green, heart-shaped leaves and d ...

. The local landscape is a mix of traditional agriculture and

quarry A quarry is a type of open-pit mining, open-pit mine in which dimension stone, rock (geology), rock, construction aggregate, riprap, sand, gravel, or slate is excavated from the ground. The operation of quarries is regulated in some juri ...

ing activity, with

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

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 Repub ...

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

is also practised.

Turlough

Flora

Fauna

References

See also