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The North German Plain or Northern Lowland〔 is one of the major geographical regions of Germany. It is the German part of the North European Plain. The region is bounded by the coasts of the North Sea and Baltic Sea to the north and Germany's Central Uplands (''die Mittelgebirge'') to the south. In the west, the southern boundary of the North German Plain is formed by the Lower Saxon Hills - specifically the ridge of the Teutoburg Forest, the Wiehen Hills, the Weser Hills and the Lower Saxon Börde - which partly separate it from that area of the Plain known as the Westphalian Lowland. Elements of the Rhenish Massif also act a part of the southern boundary of the plain: the Eifel, Bergisches Land and the Sauerland. In the east the North German Plain spreads out beyond the Harz mountains and Kyffhäuser further to the south as far as the Central Saxon hill country and the foothills of the Ore Mountains. ==Landscape, soils and their formation== It is known that the North German Plain was formed during the Pleistocene era as a result of the various glacial advances of terrestrial Scandinavian ice sheets as well as by periglacial geomorphologic processes. The terrain may be considered as part of the Old or Young Drift (''Alt-'' or ''Jungmoräne''), depending on whether or not it was formed by the ice sheets of the last glacial period, the Weichselian Ice Age, The surface relief varies from level to undulating. The lowest points are low moorlands and old marshland on the edge of the ridge of dry land in the west of Schleswig-Holstein (the Wilster Marsh is 3.5 metres below sea level) and in the north west of Lower Saxony (Freepsum, 2.3 metres below sea level). The highest points may be referred to as Vistula and Hall glaciation terminal moraines (depending on the ice age which formed them) – e.g. on the Fläming Heath (200 metres above sea level) and the Helpt Hills (179 metres). Following the ice ages, rain-catching high moor bogs originated in western and northern Lower Saxony during warm periods of high precipitation (cf the Atlantic warm period). These bogs were formerly widespread but much of this terrain has now been drained or otherwise superseded. The coastal areas consist of Holocene lake and river marshes and lagoons connected to Pleistocene Old and Young Drift terrain in various stages of formation and weathering. After or during the retreat of the glaciers, wind-borne sand often formed dunes, which were later fixed by vegetation. Human intervention caused the emergence of open heath such as the Lüneburg Heath, and measures such as deforestation and the so-called ''Plaggenhieb'' (removal of the topsoil for use as fertiliser elsewhere) caused a wide impoverishment of the soil (Podsol). The most fertile soils are the young marshes (''Auen-Vegen'') and the Börde areas (Hildesheim Börde, Magdeburg Börde, with their fertile, loess soils). High level bog peat can be found in the poorest soils, e.g. in the Teufelsmoor. In the loess areas of the lowland are found the oldest settlement locations in Germany (Linear Pottery culture). The north eastern part of the plain (Young Drift) is geomorphologically distinct and contains a multitude of lakes (e.g. the Mueritz lake in the Mecklenburg Lake Plateau) which are vestiges of the last ice age. The retreating glaciers left this landscape behind around 16,000 to 13,000 years ago. In comparison, the dry plains of northwestern Germany (Lower Saxony, western Schleswig-Holstein and the Bochum area of North Rhine Westphalia) are more heavily weathered and levelled (Old Drift) as the last large scale glaciations here occurred at least 130,000 years ago. The region is drained by rivers that flow northwards into the North Sea or the Baltic. The Rhine, Ems, Weser, Elbe and Havel are the most important rivers which drain the North German Lowlands into the North Sea and created woods in their flood plains and folds, e.g. the Spreewald ("Spree Forest"). Only a small area of the North German Plain falls within the catchment area of the Oder and Neiße rivers which drain into the Baltic. 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「North German Plain」の詳細全文を読む スポンサード リンク
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