ranking to the lowest): Risk 9 – the coastal area in Group I; Risk 8 – the coastal area
in Group II; Risk 7 – the coastal area in Group III; Risk 6 – the coastal area in Group
IV; Risk 5 – the inland area in Group I; Risk 4 – the inland area of Group II; Risk 3 –
the inland area of Group III; Risk 2 – the inland area of Group IV; Risk 1 – interior
of Risk 2–5 areas. The illustrated risk map is in the middle section of Fig. 10.8 The
risk map shows the coastal areas such as Giao Thuy, Hai Hau, and Hoang Hoa are
the most dangerous places – they have the highest probability of encountering a
land loss problem in the near future. The deposition areas consist of new and soft
soils and are therefore easily affected by coastal erosion. The risks of the deposition
areas are also higher than those of the inland areas.
Fig. 10.4 Risk map of the coastal erosion by calculating the cluster analysis of UPGMA with the
items of Coastal Dynamics Index (CDI), banks and height of land. In the calculation, actual CDI
numeric value was used
10 Mapping Coastal Erosion Risk in the Southern Red River Delta, Vietnam
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