What is a mangrove?
The term 'mangrove', is used in the broad sense either to refer to the highly adapted plants found in tropical intertidal forest communities or the ecosystem itself. The term 'mangrove' may have been derived from a combination of the Malay word 'manggi-manggi', for a type of mangrove tree (Avicennia) and the Arabic 'el gurm', for the same, as 'mang-gurm'. As a word, it can be used to refer to a species, plant, forest or community!
A mangrove community
Nature, at the highest level of organisation, consists of the ecosphere which includes all living things (biosphere) together with non-living parts (atmosphere, hydrosphere, lithosphere). The next level is the biome which consists of groups of similar ecosystems over large geographic areas. Next is the ecosystem, which is a self-regulating community of organisms and their non-living environment.
The community, consists of interacting populations (single-species groups) of all the different plants and animals in the area, which in this case, is the mangrove. Thus essentially, the mangrove community is the biotic part of this ecosystem, which this book introduces.
Types of tropical rain forest
The term 'tropical rain forest' is used to describe forests of the ever-wet tropics or beyond, where there is, at most, minimal seasonal water shortage. These can be divided into dry-land and wetland rain forests. The first includes tropical lowland evergreen rain forest, which was the main type of forest covering Singapore, parts of which still exist in Bukit Timah Nature Reserve.
This also includes beach vegetation, which still exists along Singapore's east coast, Labrador Beach in the south, and the southern islands. Wetland rain forests include mangrove, brackish-water, freshwater and peat swamp forests. Of all these, only mangrove forests are under the direct influence of seawater.
Types of coastal habitats
The geological and environmental conditions of the shoreline result in different habitats. Exposure to currents and waves of the open sea results in the formation of rocky shore and sandy beaches. Sheltered shores, on the other hand, allow sediment from rivers and the sea to settle, and eventually become mangrove forests.
high tide (left) low tide (right)