The number of biomes in the world varies depending on how each biome is categorized. Some contend that there are five major types of biomes, while others say that there are nine or even 14 biomes.
Those that claim that there are five biomes are referring to aquatic, desert, forest, grassland and tundra biomes. These are all broad categories of biomes.
A person that claims that there are 14 biomes in the world separates the forest category into taiga, chaparral and temperate forest. According to this theory, grasslands are separated into savanna and temperate grasslands. The aquatic category is divided into freshwater, freshwater wetlands, marine, coral reef and estuaries. The alpine category is also included.
Those that contend that there are nine biomes are only referring to geographical biomes and are not considering aquatic biomes.