The World's Biomes: Climate and Biomes

Vegetation on Earth takes on characteristic forms according to climate (temperature and precipitation). This is called a biome.

Basic Knowledge

A biome is a group of all organisms distributed in a particular climate zone, named mainly according to vegetation (physiognomy). When temperature and precipitation are used as two axes, the world's major biomes are classified as follows.
Tropical and subtropical (hot and humid)
・Tropical rainforest: Many species of evergreen broad-leaved trees. Amazon, Congo, and Southeast Asia.
・Subtropical rainforest: Okinawa and Taiwan.
・Monsoon forest: Tropical regions with wet and dry seasons. Deciduous broad-leaved trees such as teak and sala.
Temperate
・Laurel forest: Warm-temperate zone. Evergreen broad-leaved trees such as sudajii and tabunoki, with glossy cuticles. South of the Kanto region of Japan.
・Deciduous broad-leaved forest: Cool-temperate zone. Deciduous broad-leaved trees such as buna and mizunara. Tohoku and southern Hokkaido.
・Sclerophyll forest: Mediterranean climate (dry summers and rainy winters). Olive and cork oak.
Subarctic and polar
・Coniferous forest (taiga): Subarctic zone. Ezomatsu, todomatsu, and karamatsu. Russia and Canada.
・Tundra: Polar zone. Mosses, lichens, and shrubs.
Arid regions
・Savanna: Tropical grassland. Africa.
・Steppe: Temperate grassland. Mongolia and the North American prairie.
・Desert: Extremely little precipitation. Cacti and other plants.

Further Exploration

On a biome distribution diagram (vertical axis: mean annual temperature; horizontal axis: annual precipitation), major biomes are arranged so that deserts are in the lower left and tropical rainforests are in the upper right. Even with the same annual precipitation, vegetation changes greatly: lower temperatures produce coniferous forests, while higher temperatures produce tropical rainforests.
Japan stretches from north to south and has climate zones ranging from subtropical to cool-temperate. Therefore, its latitudinal distribution includes diverse biomes: Okinawa has subtropical rainforests, Kyushu to Kanto has laurel forests, Tohoku to southern Hokkaido has deciduous broad-leaved forests, and eastern and northern Hokkaido has coniferous forests. In learning, it is standard to remember the representative tree species of each biome (tropical rainforest: dipterocarps; monsoon forest: teak; laurel forest: sudajii; deciduous forest: buna; coniferous forest: ezomatsu; sclerophyll forest: olive).

Points to Note

① Do not confuse laurel forest (warm-temperate and evergreen) with deciduous broad-leaved forest (cool-temperate and deciduous). ② Monsoon forest and deciduous broad-leaved forest have similar names but are different: monsoon forests lose leaves in the tropical dry season, while deciduous broad-leaved forests lose leaves in the cool-temperate winter. ③ Sclerophyll forests are characteristic of the Mediterranean climate of dry summers and rainy winters. ④ Distinguish the three grassland and desert systems: savanna (tropical), steppe (temperate), and tundra (polar).

Practice

1. What is the biome south of Kanto in Japan that is centered on evergreen broad-leaved trees such as sudajii?
2. What is the cool-temperate biome centered on buna called?
3. What biome with thick, hard-leaved trees such as olive is found in a Mediterranean climate?