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The Loe ((コーンウォール語:An Logh)), also known as Loe Pool, is the largest natural freshwater lake () in Cornwall, United Kingdom. The earliest recorded appearance of this simple name form was in 1337, when it was called "La Loo",〔Padel, O. J. ''Cornish Place Names'', p. 122.〕 but is mentioned as 'the lake' in 1302;〔Toy's ''History of Helston'', pp. 384 - 394.〕 Situated between Porthleven and Gunwalloe and downstream of Helston, it is separated from Mount's Bay by the shingle bank of Loe Bar. Both the Loe (including the southern arm known as Carminowe Creek) and Loe Bar are situated within the Penrose Estate, which is administered by the National Trust,〔National Trust. (Penrose Estate: Gunwalloe and Loe Pool ). Retrieved 28 November 2010.〕 and are designated as a Site of Special Scientific Interest by Natural England.〔Natural England. (SSSI units for Loe Pool ). Retrieved 28 November 2010.〕 It is within the Cornwall Area of Outstanding Natural Beauty〔Cornwall Area of Outstanding Natural Beauty. http://www.cornwall-aonb.gov.uk/〕 and is considered a classic Geological Conservation Review Site.〔May, V.J. Loe Bar. In May, V.J. and Hansom, J.D. (2003) Coastal Geomorphology of Great Britain, Geological Conservation Review Series, No. 28, Joint Nature Conservation Committee, Peterborough, 754 pp.〕 The South West Coast Path, which follows the coast of south-west England from Somerset to Dorset passes over Loe Bar. ==Formation of Loe Bar== The Loe was originally the estuary of the River Cober, a ria or drowned river valley now blocked by a sand and shingle bar with a fresh water lake behind. The valley can be traced several kilometres out to sea.〔http://projects.exeter.ac.uk/geomincentre/03Porthleven%20to%20Polurrian.pdf〕 The age of the bar is disputed, with estimates ranging from several thousand years to c. 700 years. With the melting of ice-sheets and glaciers after the last ice age, sea levels rose and reached their present levels about 6,000 years ago during what is known as the Flandrian Marine Trangression. The most likely origin is a barrier beach, (formed by wave action rather than by tides) that gradually moved onshore, as the sea level rose during the Holocene.〔http://jncc.defra.gov.uk/pdf/gcrdb/GCRsiteaccount1847.pdf〕 The shingle coming from drowned terraces of the former river that flowed down the English Channel (the nearest onshore source is 120 miles away in East Devon).〔 It is thought that Longshore Drift plays an important part in the maintenance of the Bar, with a strong current flowing to the south-east from Porthleven to Gunwalloe, depositing shingle along the Bar. The ebb flow is not a simple reverse flow and is not strong enough to remove all the deposits.〔Murphy, R.J., (1986). A Study of Loe Bar. In Cornish Studies 14:23–33.〕 The bar itself is a sediment sink as far as the overall beach budget is concerned.〔 The deposits have been tentatively dated as Eocene〔 and compared with Gunwalloe beach material, very little of the Loe Bar shingle is locally derived. The composition of the Bar deposits are: Chalk flint 86%, Quartz 9%, Grit 2.6%, Greensand chert 2% and Serpentine 0.5%.〔 The bar has increased significantly in historic times. Leland who visited the west country in 1542, reported that the bar was breached once in 3–4 years by storms causing sea water to mix with fresh in the pool, but it soon resinstated. Carew's ''Survey of Cornwall'' (1602) warns wayfarers using the bar as a footpath against times when the bar is washed away by the river's force "and some have so miscarried".〔Quoted in 〕 Early maps such as Speed (1674) and Tindal (1732) do not show the bar but Martyn's 'New and Accurate Map of the County of Cornwall' (1784) shows the 'Loe Bar'. However sea water still accumulated in the Loe from gales in the nineteenth century and had to be released by cutting the bar. The deepest sediments retrieved from the pool date from the first quarter of the 19th century. Cutting the bar would often reduce the height in the pool by because of the strong rush of water exiting from the pool (so that the breach in the bar was at least that deep) leaving much of the lake empty, and 1875 on was probably the first time in its history that the pool was predominantly fresh throughout the year rather than salt or brackish, producing significant changes in the lake ecology. Daniel Defoe in his tour around Great Britain writes that the River Cober makes a tolerable good harbour and several ships are loaded with tin, although over one hundred years before Defoe, Richard Carew (1602) described Loe Bar as ''"The shingle was relatively porous and fresh water could leave and seawater enter depending, on the relative heights of the pool and sea"'' Daniel Defoe, writing in the early 18th century, appears to state that ships were then able to trade up the Cober to Helston; this would seem to be the origin of other documentary sources claiming a port for the town in the historic period. There is no known archaeological evidence for the existence of a port at Helston and there is no primary evidence to support Defoe’s account.〔 * Some formation of the Bar is implied in the reference to Chyvarloe as 'Tywarlo', meaning 'the house over the pool' in 1235.〔title=Five coast and country trails Penrose/National Trust.〕 To prevent flooding in parts of Helston, the Bar has occasionally been breached, a practice known locally as "cutting", with the last occurring in 1984. The Bar has always resealed itself.〔Le. Messurier, B. and Luck, L. (1998) ''Loe Pool and Mount's Bay''. No. 12 in The National Trust Coast of Cornwall series of leaflets.〕 The 2013 investigations show a chart of a cross-section of part of the valley between Loe Bar and Helston as being built from twenty-five feet of silt upon seven feet of sea sand, above layers of peat from the remains of vegetation or of the ancient forest, that once covered Mount's Bay.〔DVD on 'Could Helston have been a port?'〕 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「The Loe」の詳細全文を読む スポンサード リンク
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