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The River Barle runs from the Chains on northern Exmoor, in Somerset, England to join the River Exe at Exebridge, Devon. The river and the Barle Valley are both designated as biological Site of Special Scientific Interest. On the Chains above Simonsbath is a reservoir known as Pinkery Pond. It was formed by damming the River Barle, in the 19th century by John Knight and his son, and was originally intended to be . The purpose is unknown but close to the pond is the remains of a small canal. Wheal Eliza Mine was an unsuccessful copper and iron mine on the river near Simonsbath. The river passes under a late medieval six arch stone Landacre Bridge in Withypool, and the Tarr Steps a prehistoric clapper bridge possibly dating from 1000 BC. The stone slabs weigh up to 5 tons apiece. According to local legend, they were placed by the devil to win a bet. The bridge is long and has 17 spans. It has been designated by English Heritage as a grade I listed building.〔(【引用サイトリンク】 work=Images of England )〕 In Dulverton the river is crossed by the Barle Bridge. ==Ecology== The river flows through the Somerset Wildlife Trust's Mounsey Wood Nature Reserve and Knaplock and North Barton SSSI notified in 1954. The site is within Exmoor National Park. The Barle Valley contains extensive tracts of ancient upland sessile oak ancient woodland which exhibit variations in structure and species composition as a result of difference in past management, geology and topography. The diversity of the site is increased substantially by areas of valley mire, heathland and acid grassland. Eighty five woodland vascular plant species have been recorded including thirty one ancient woodland indicators from a single compartment. The meadows are one of the few sites for great burnet (''Sanguisorba officinalis'') on Exmoor. Springs emerging from the base of sandstone slopes generate nutrient poor acid mires dominated by Sphagnum and Polytrichum moss carpets. The lichen flora is exceptional both for its luxuriance and in the number of rare species. One hundred and sixty five taxa of epiphytic lichens are present containing a remarkably large proportion of ancient woodland indicators giving the Barle a very high index of ecological continuity. The site contains an outstanding assemblage of woodland breeding birds including particularly high densities of wood warbler (''Phylloscopus sibilatrix''), redstart (''Phoenicurus phoenicurus'') and pied flycatcher (''Ficedula hypoleuca''). The River Barle provides an important habitat for kingfisher (''Alcedo atthis''), dipper (''Cinclus cinclus'') and grey wagtail (''Motacilla cinerea''), while scrub and heath have breeding stonechat (''Saxicola torquata'') and whinchat (''Saxicola rubetra''). Twenty species of butterfly have been recorded in the valley including the nationally scarce marsh fritillary (''Eurodryas aurinia'') and nationally vulnerable high brown fritillary (''Argynnis adippe''). Both roe deer (''Capreolus capreolus'') and red deer (''Cervus elaphus'') graze areas of wood pasture. The presence of otters (''Lutra lutra'') on the Barle has been regularly recorded. A colony of dormice (''Muscardinus avellanarius'') inhabits at least one of the hazel coppices.〔(【引用サイトリンク】 work=English Nature )〕 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「River Barle」の詳細全文を読む スポンサード リンク
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