geology, climate and soil
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Geology, climate and soil The Hungarian Plain is a land-locked lowland surrounded by mountains. Between 230 and 140 million years ago, the basin was part of the huge Tethys Sea, the mother of the present day Mediterranean Sea. A part of this ancient sea was isolated by the formation of the Alps, Dinaric Alps and Carpathians to create the smaller Pannonian Sea, an inland water body, similar to today’s Black Sea. The Pannonian Sea reached its maximum size in the late Pliocene era, some two million years ago, and is thought to have covered most of the present-day plain. The sea deposited a layer of up to 3,000 metres of marine sediment. In a later period of tectonic upheaval, the fringes of the lowland plateau started to rise and the sea retreated to the south-east. Increased input from rivers turned the remaining sea into a freshwater lake that eventually emptied into the Black Sea through the Iron Gates gorge, the grand gateway through the Balkan mountains on the border of Serbia and Romania where today the Danube River flows. During the Ice Ages, a broad belt of loess -a very fine-grained, silty-loamy soil- was deposited over the Hungarian Plain. Loess is formed when sheets of ice grind the underlying bedrock. When dry, loess is easily wind-blown. After the ice ages it has spread over a great belt on the southern edge of the former ice sheet, including the Hortobágy region.
Only a thin vegetation of herbs and grasses can grow on the alkaline soils of the Hortbágy. Wild Chamomile is one of them and occurs locally in abundance.
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hortobágy