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The Inner Tay Estuary, the inner, western part of the Firth of Tay, stretching from the Tay Railway Bridge in the east to the Queen's Bridge over the River Tay in Perth and the bridge in Bridge of Earn on the River Earn. The estuary is one of the largest in eastern Scotland and is up to 2.5 km wide. The estuary consists primarily of inter-tidal sand and mud flats that extend seaward out to the main channel of the estuary, the majority of which lie on the northern shore. Landward of these are saltmarsh and ''Phragmite''s reedbeds. There are two large islands: Mugdrum Island opposite Newburgh and Moncreiffe Island immediately below Perth. The narrow form of the estuary and the large volume of freshwater from the Rivers Tay and Earn restrict the influence of salt water west of the Tayport narrows. Much of the tidal water in the estuary is freshwater or mildly brackish. ==Nature conservation== The 20 km or so stretch between the railway bridge and the confluence of the Rivers Tay and Earn is a site of special scientific interest. The current SSSI was notified in August 1999 and extends to 4,115 hectares or thereby. Scottish Natural Heritage provides more information about the SSSI in its site management statement.〔(【引用サイトリンク】title=Inner Tay Estuary Site of Special Scientific Interest: Site management statement )〕 Perth & Kinross Council and Dundee City Council manage part of the north shore as a local nature reserve.〔(【引用サイトリンク】title=Detailed information for Inner Tay Estuary LNR )〕〔(【引用サイトリンク】title=Inner Tay Estuary Local Nature Reserve Draft Two Management Plan )〕 RSPB manages areas of reedbed. The ''Phragmites'' reedbeds on the north shore stretch for some 15 km and are thought to be the largest and most continuous in the UK. The reedbeds are tidal and flooded on spring tides. They support nationally important breeding bird populations. With the help of groynes built out into the estuary, reedbeds were planted in the 19th century to protect agricultural land, and have since expanded naturally. Much of the agricultural land was formerly marsh which itself had been drained and cultivated by Cistercian monks in the 15th and 16th centuries. In 1974 commercial harvesting of the reedbeds for thatching reed began, and has continued to the present day, albeit now on a reduced scale by RSPB. At its height approximately 30-40% of the reedbeds were cut by Tayreed (company) on an annual rotation (single wale) using a mechanical harvester known as a Seiga. Even at that extent the cutting was thought to have been compatible with, if not beneficial for, the bird, plant and insect interest of the reed beds. The best remaining saltmarsh is at the eastern, seaward end of the reedbeds and these support locally rare saltmarsh plants including sea club-rush ''Bolboschoenus maritimus'', grey bulrush ''Schoenoplectus tabernaemontani'' and common saltmarsh grass ''Puccinellia maritima''. The Inner Tay was the type locality of the midge ''Culicoides machardy'' (1960) but the species was rduced to a junior synonym of the previously described ''Culicoides machuriensis'' - a species of northern China, northern Russia, Scandinavia and Sctland. The mudflats of Invergowrie Bay are the first in Britain found to support the large polychaete worm ''Marenzellaria viridis'' - a species normally found only in north-eastern North America. Scottish Natural Heritage has commissioned and published habitat survey reports for the Inner Tay Estuary.〔(【引用サイトリンク】title=Central Environmental Surveys (2003). Habitat survey Inner Tay Estuary 2002]. Scottish Natural Heritage Commissioned Report No. 003 (ROAME No. F01LH04B) )〕〔(【引用サイトリンク】title=Bates, C. R., Moore, C. G., Malthus, T., Mair, J. M. and Karpouzli, E. (2004). (Broad scalemapping of habitats in the Firth of Tay and Eden Estuary, Scotland ). Scottish Natural Heritage Commissioned Report No. 007 (ROAME No. F01AA401D) )〕 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「Inner Tay Estuary」の詳細全文を読む スポンサード リンク
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