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Slade Brook () is a biological and geological Site of Special Scientific Interest in Gloucestershire, notified in 2003.〔(Natural England SSSI information on the citation )〕〔(Forest of Dean District Local Plan Review, adopted November 2005, Appendix D 'Nature Conservation Site Designations Within the Forest of Dean District', Sites of Special Scientific Interest )〕 ==Location and habitat== The site, which include an active tufa-forming stream, is in the Forest of Dean plateau and Wye Valley Area of Outstanding Natural Beauty. The stream system has a series of tufa dams, plunge pools and connecting stream sections. This results from a combination of physical and chemical processes.〔 The Slade Brook rises on the Carboniferous Limestone of the Forest of Dean. It flows for two kilometres before joining the River Wye, which is also notified as an SSSI. Approximately a kilometre section of the stream includes the main focus of tufa deposition.〔 Rainwater (which percolates into sinkholes in the limestone), is enriched with dissolved calcium carbonate. When emerging from springs along the Brook, the removal of carbon dioxide causes precipitation of calcium carbonate. The main deposits of the calcium carbonate are at a series of dam-like structures, which are constructed of tufa.〔 The process is assisted by vegetation (which includes tree litter such as twigs and branches), alae and mosses. The flow of the stream is slowed down and photosynthesis encourages the removal of the carbon dioxide. The vegetation and debris then become the area for tufa accumulation.〔 The site is significant as tufa dams actively forming are relatively rare and this site has approximately sixty. They enable research into the origins of fossil tufa dams as well as modern formations〔 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「Slade Brook」の詳細全文を読む スポンサード リンク
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