Mangroves provide a wide range of well-documented ecosystem services, such as coastal protection from storm waves and surges, a nursery function for many juvenile marine animals including commercially important (fish and shellfish) species, carbon sequestration, providing wood and charcoal, etc. The relative importance of these services varies between locations.

The foundation species (i.e., the most abundant species building the system) in the mangroves around South-East Asia can be divided in pioneering and non pioneering species:

  • Pioneers
    • Avicennia spp.
    • Sonneratia spp.
  • Non-pioneers
    • Rhizophora spp.
    • Bruguiera spp.
    • Ceriops spp.
    • Xylocarpus spp.
    • Heritiera spp.

Figure 3 depicts the zonation in mangrove forests depending on the inundation levels, with the mudflat in front of the forest (zone 1), the pioneer zone (zone 2), and the non-pioneer zones (zone 3+4). A complete overview of mangrove species around the world can be found in Tomlinson (1986) and the World Atlas of Mangroves (Spalding, 2012).

The area of mangroves is globally declining due to population growth and coastal squeeze; mangrove areas have been replaced by economically driven other land uses. The most important threats to the remaining mangroves are:

  • coastal erosion
  • direct anthropogenic impacts: land reclamation, harbour construction, shrimp farming, etc.
  • risk of oil and other chemical spills from ships
  • accelerated sea-level rise and the ensuing coastal squeeze.