Dyke design, floodplain restoration and mangrove co-management as parts of an area coastal protection strategy for the mud coasts of the Mekong Delta, Vietnam

Abstract

The dynamic coastlines in the Lower Mekong Delta of Vietnam are threatened by the impacts of climate change, particularly by the increased intensity and frequency of storms and floods, as well as by rising sea levels. The most effective coastal protection systems consist of different elements arranged in series, for instance natural floodplains vegetated with mangroves and a sound dyke line. However, the unsustainable use of natural resources and development in the coastal zone are threatening the protection function of the mangrove forest belt. In sites where severe erosion has destroyed the mangrove belt, restoration of floodplains and mangrove rehabilitation is only possible after the wave energy has been reduced by physical barriers. This can be achieved with bamboo fences, which reduce erosion and stimulate sedimentation. Restoration of the eroded floodplains creates the preconditions for rehabilitation of the destroyed mangrove forest. Mangrove management is an important element of an area costal protection strategy.

Monitoring changes in land use and distribution of mangroves in the southeastern part of the Mekong River Delta, Vietnam

“…Local farmers have individually expanded their aquaculture land without land-use planning. Besides, there are small new segments of the mangroves that were planted along the coast, especially in the mudflats area outside the sea dyke systems (Albers et al, 2015;Joffre et al, 2018).…”

Exceptional rates and mechanisms of muddy shoreline retreat following mangrove removal

“…This situation is worsened by the belief that mangroves create an unhealthy environment (Nijbroek (). Similar observations have also come from other tropical field sites where the muddy coastline is engineered, such as in Thailand (Winterwerp et al ., ), and Vietnam (Albers and Schmitt, ).…”

Sedimentation and Survival of the Mekong Delta: A Case Study of Decreased Sediment Supply and Accelerating Rates of Relative Sea Level Rise

“…A complicating factor is the rise in eustatic and relative sea level in the Mekong Delta that is the focus of the next section. The possibility of future shoreline erosion associated with a combined decline in sediment delivery and increase in the rate of sea level rise has resulted in several studies that suggest strategies such as (1) non-structural adaptation of coastal populations (Boateng, 2012), (2) creation of barriers using natural materials (Albers and Schmitt, 2015), and (3) increased planting of mangroves on sea-facing shorelines (Phan et al, 2015).…”