March 21, 2017. Earth / A Geography of Hope
Cyril F. Kormos, Russell A. Mittermeier, Tilman Jaeger, Brendan Mackey
Forests cover some 4 billion hectares worldwide, about one third of the terrestrial surface of the planet. At the broadest level, three vast biomes can be distinguished: boreal, temperate and tropical forests. These three major biomes show pronounced differences in terms of their ecology, history, status, and conservation prospects, but face a similar range of threats throughout the world.
Named after “Boreas”, god of the north wind in Greek mythology, the circumpolar boreal forests constitute the world’s largest forest biome. Some two-thirds of the forest biome are located in Siberia, and the remainder is shared by Alaska and Canada, with smaller but important expanses in Scandinavia, Central Asia and Mongolia.
Temperate forests remain only in a patchy distribution across the United States, Europe and the Asian mid-latitudes. Outstanding examples with important expanses of primary temperate forests include the Valdivian Forests of Chile and Argentina, the lesser-known Caspian Forests of Iran and Azerbaijan, and the Manchurian Mixed Forests. Fascinating and irreplaceable temperate rain forests cover the northwestern coast of North America from northern California to southern Alaska, and parts of the coast of southern Chile, New Zealand and Australia.
The largest expanses of tropical forest are found in Amazonia and the Congo Forest, in parts of Southeast Asia, and on New Guinea. Concretely, tropical forests are mostly distributed across South and Central America, West and Central Africa, Asia and Oceania. While acknowledging definitional challenges, as well as the limits and uneven distribution of available data, it is estimated that there are around 1.2 billion hectares of closed tropical forest worldwide. Roughly one-half is located in South America (some 600 million hectares), followed by Africa with some 275 million hectares, and Asia with some 220 million hectares. The remainder is distributed across Oceania and North and Central America.
This is an excerpt from the CEMEX Nature Series Book “A Geography of Hope: Saving the Last Primary Forests” (2016)