Tropical depressions and storms constrain the distribution of mangroves. In the coastal plains of the north, the soil is very rich in alluvia but mangroves only form narrow stretches inside the river mouths because they cannot grow at spots with strong waves and winds. This has also resulted in the devastation of the sheltered nurseries and spawning grounds of many species of sea animals as well as water birds. A storm accompanied by heavy rain can break mangrove branches, cause flowers and fruit to fall off and carries a lot of seedlings into the sea. There are also indirect relationships between climate change and the mangrove ecosystem through changes in sea level.
Inundation is only one of the effects.
As sea level rises, coastal erosion and the severity of coastal flooding will increase and coastlines will recede unless they are stabilized by dykes or through sand nourishment. Salt water intrusion into ground water, rivers, bays and estuaries will increase. Changes in rainfall patterns and in temperature will modify salinity gradients in estuaries and alter rates of river delta sedimentation. Coastal currents and upwelling patterns are likely to shift geographically and change in intensity. There are a number of causes for sea level rise in the Vietnamese coastal and riverine areas.