Land use change and sustainable living way with flooding in the Mega Delta of South East Asia

Research Project , Research Report 2004

Shigeko HARUYAMA Graduate school of Frontier Science, The Univ. of Tokyo

Abstract

The Asia Pacific region is one of the most hazardous region where located in active tectonic movement and intensity rainfall zone in monsoon Asia. In Japan, many Typhoons attacked coastal provinces and the floods caused extensive damages to the suburban areas and rural area in last summer, 2004. The considerable paddy fields situated in the fringe areas of low-lying mega-cities had disappeared due to urbanization during the economic growth. This transformation and land use change brought the loss of inundation capacity of lands; hence rainwater concentrated and was running into the river protected by artificial embankments and downstream city area immediately with serious flooding damage. Last 50 years, Japan tried to prepare hard infrastructures, such as, “Dam construction, Dike construction, Floodway construction etc.” against flooding, however, probability of precipitation and precipitation intensity and flood frequency and return period of flooding has been increasing.
Mega cities of South East Asia have been remarkable urban sprawl and dynamic change of the Natural and Human environment. Risk against natural hazard has been increasing in these cities and suburban area is also becoming more vulnerable against natural hazard. One of the huge city is Hanoi capital where is located on the alluvial plain in the great delta. The Red river Delta of Northern Part of Vietnam has been remarkable changed in the Late Quaternary Period and the these alluvial plain along the Red River has been constructed and formed for fluvial geomorphology affected by great response from continuous sea level change under the global climatic change in the Holocene period. Sea level change and their influences on the tropical delta and sub-tropical delta are multiple diversities in South East Asia. In this project, considering for each climatic specific features and near future global warming, delta and sea linkage were studied and researched assessment from response of climatic change. We tried to describe paleo-geography in the delta.

Keywords:

Red River Delta, Living with disaster, Land use change