Agriculture, Fisheries and Conservation Department



Adaptation of Mangroves

  • As mangroves grow in inter-tidal zone, their trunk and even their canopy may be covered by tidal water during high tide period. The mangroves also face the risk of being washed away by tides due to the unstable substratum.

  • However, mangroves have many special features for adapting to such stressful coastal environment. These amazing structures make them different from the other terrestrial plants.


  • [A dropper of Bruguiera gymnorrhiza]

    A dropper of Bruguiera gymnorrhiza

    Germinated seeds that attach to the parent plant of mangroves (e.g. Bruguiera gymnorrhiza) after germination.
  • This kind of viviparous reproduction allows rapid growth and establishment of mangrove seedlings once they come into contact with the substratum.
  • It increases the survival rate of the mangroves in the unstable substratum and the intertidal environment.

[Prop roots of Kandelia obovata]

Prop roots of Kandelia obovata

Prop roots

  • Branched supporting roots that arise from the lower trunk of some mangrove species (e.g. Kandelia obovata).
  • Provide additional stability to the trees in the soft unstable substratum by broadening the tree base.

[Pneumatophores of Avicennia marina]

Pneumatophores of Avicennia marina


  • Erect aerial roots arising from cable roots to facilitate gaseous exchange of the roots of some mangrove species (e.g. Avicennia marina) under water-logged soil condition
  • Contain aerenchyma tissue to allow rapid gaseous transportation.

["Knee" of roots of Bruguiera gymnorrhiza]

"Knee" of roots of Bruguiera gymnorrhiza

"Knees" of roots

  • The roots of some mangrove species (e.g. Bruguiera gymnorrhiza, Kandelia obovata) form into "knees" that project above the mud surface to facilitate gaseous exchange.

[Salt glands of Aegiceras corniculatum]

Salt glands of Aegiceras corniculatum

Salt glands

  • Present in the leaves of some mangrove species (e.g. Aegiceras corniculatum).
  • Used to concentrate and actively excrete the absorbed salts so as to regulate the salt concentration inside the mangroves.
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Last Review Date : 29 July 2015