Đồng Bằng Sông Hồng

location

The region of Đồng Bằng Sông Hồng is located in the north (Red River Delta)

The Red River Delta (Vietnamese Đồng Bằng Sông Hồng ) is a region in northern Vietnam ( Bắc Bộ ). It is shaped by the river system of the Red River ( Sông Hồng ), which it formed with its sediment deposits. The river system flows into the Gulf of Tonkin (Vietnamese Vịnh Bắc Bộ, Chinese 北部湾 Beibu Wan). The most important cities are Hanoi , Hải Phòng , Thái Bình and Nam Định .

Geology and vegetation

The delta at Haiphong

The location of the delta has fluctuated significantly over the course of the earth's history; for example, about 4,000 years ago the sea level was 5 to 6 meters higher, so that the mouth was west of Hanoi (Higham 1989) .

The amount of sediment that has always been carried along has increased significantly in recent years due to deforestation , intensive cultivation and high soil erosion in the catchment area and is currently around 10,000,000 t annually, i.e. H. 1.5 kg per m³ of water. This results in a heavy soil order and a growth of the delta by around 100 m per year. The red river is also notorious for its strong seasonal fluctuations in the amount of water and its heavy flooding.

Since the eleventh century, these conditions have forced the Vietnamese to contain the river system with dykes, which today are designed for a water flow between 49,000 and 57,000 m³ / s. The highest value to date of 37,000 m³ / s was measured in 1945. The diked river bed is now partly higher than the surrounding land. The maximum tidal range on the coast of the delta is approx. 4 m. If the Intergovernmental Panel on Climate Change ( IPCC) predicts that sea levels will rise, the entire delta, which is only between 1 m and 3 m above sea level, is at risk.

Various multinational commissions, such as the Flocods ( FLOod COntrol Decision Support ) project, deal with the threats to the river system and its delta .

National parks and nature reserves

The Red River Delta was included in the UNESCO MAB program as a biosphere reserve in 2004 .

administration

Irrigation of rice fields between Hà Nội and Hoa Binh. In the absence of electrical connections in the fields, this work is still done manually today.

Provinces

Cities with provincial status

population

The Delta is the region of origin of the Kinh people . With 15% of the Vietnamese population, the region is one of the most densely populated in the world.

History and meaning

The delta with its fertile sediment deposits is a major area of agricultural production in Vietnam. About 47% of the area (820,800 hectares) is agricultural land, on which more than a third of the country's rice production is grown. The irrigation and drainage takes place through a sophisticated system of dams, dykes and canals. The total length of the dikes, which are up to 40 m wide at the base, is more than 3000 km today, and there are often traffic routes on the crowns.

The region was heavily bombed during the Vietnam War .

Individual evidence

^ Charles Higham: The Archeology of Mainland Southeast Asia . Cambridge University Pr., 1989, ISBN 0-521-27525-3

literature

Bas van Maren: Morphodynamics of a cyclic prograding delta. The Red River, Vietnam . Royal Dutch Geographical Society et al., Utrecht 2004, ISBN 90-6809-363-0 , ( Nederlandse geografische studies 324), ( Also : Utrecht, Univ., Diss., 2004).

Piet Hoekstra, Tjeerd CE van Weering: Morphodynamics of the Red River Delta, Vietnam . In: Journal of Asian earth sciences 29, 2007, 4, ISSN 1367-9120 , pp. 505-507.

Web links

UNESCO MAB Program: Red River Delta

21 106Coordinates: 21 ° 0 ′ N , 106 ° 0 ′ E

[1] Charles Higham: The Archeology of Mainland Southeast Asia . Cambridge University Pr., 1989, ISBN 0-521-27525-3