Mangrove forests are a feature of the intertidal zone of tropical and subtropical coastlines. They have developed several unique morphological and physiological characteristics to adapt to their shifting, saline and muddy environment as they play an important role in coastal protection and maintenance of both water quality and biodiversity. Mangroves have high economic, ecological and social significance but are continually under threat from coastal development, excessive wood gathering, fishpond operations, diversion of freshwater and mining or extraction of minerals.
Although there is greater interest in mangrove afforestation programs, difficulties occur in ensuring a reliable supply of selected propagules for increasing the number and scale of plantings. Mangroves present particular problems of seed collection due to the nature of the habitat, of seed viability, which is only for short periods each year, and of seed storage since storage life is short and most seeds are large. The survival of mangrove seedlings in the field is also generally poor because of the dynamic nature of their habitat, thus replacement plantings often need to be undertaken for up to three years (Saenger and Siddiqi, 1993).