Mangroves are woody trees or shrubs that grow in mangrove habitats or mangal (Hogarth, 1999). The mangrove is often considered a type of biome. Mangrove habitat is exclusively tropical and tidal, and therefore having soil or sediment that is water-logged and saline or of variable salinity. Areas where mangal occurs includes estuaries and marine shorelines. A wide variety of plant species can be found in mangrove habitat, but some 54 species in 20 genera, belonging to 16 families constitute the "true mangroves" — species that occur exclusively in mangrove habitats and rarely elsewhere (Hogarth, 1999).

A biome is an area on the earth's surface that has a certain set of characteristics. There are seven kinds of biomes in the world: tundra, taiga, temperate forest, tropical rainforest, desert, grassland, and ocean. The map above shows where each of these biomes can be found around the world. Although it does not appear in the key, the ocean is represented by the blue area on the map.

A biome is a large geographical area of distinctive plant and animal groups, which are adapted to that particular environment. The climate and geography of a region determines what type of biome can exist in that region. Major biomes include deserts, forests, grasslands, tundra, and several types of aquatic environments. Each biome consists of many ecosystems whose communities have adapted to the small differences in climate and the environment inside the biome. All living things are closely related to their environment. Any change in one part of an environment, like an increase or decrease of a species of animal or plant, causes a ripple effect of change in through other parts of the environment. The earth includes a huge variety of living things, from complex plants and animals to very simple, one-celled organisms. But large or small, simple or complex, no organism lives alone. Each depends in some way on other living and nonliving things in its surroundings.