įorests at different latitudes and elevations, and with different precipitation and evapotranspiration form distinctly different biomes: boreal forests around the North Pole, tropical moist forests and tropical dry forests around the Equator, and temperate forests at the middle latitudes. Net primary production is estimated at 21.9 gigatonnes of biomass per year for tropical forests, 8.1 for temperate forests, and 2.6 for boreal forests. įorests account for 75% of the gross primary production of the Earth's biosphere, and contain 80% of the Earth's plant biomass.
The largest share of forests (45 percent) are in the tropical latitudes, followed by those in the boreal, temperate, and subtropic domains. More than half of the world's forests are found in only five countries (Brazil, Canada, China, the Russian Federation, and the United States of America). įorests are the predominant terrestrial ecosystem of Earth, and are distributed around the globe. It does not include land that is predominantly under agricultural or urban use." Using this definition, Global Forest Resources Assessment 2020 (FRA 2020) found that forests covered 4.06 billion hectares (10.0 billion acres 40.6 million square kilometres 15.7 million square miles), or approximately 31 percent of the world's land area in 2020. The United Nations' Food and Agriculture Organization (FAO) defines a forest as, "Land spanning more than 0.5 hectares with trees higher than 5 meters and a canopy cover of more than 10 percent, or trees able to reach these thresholds in situ. Hundreds of definitions of forest are used throughout the world, incorporating factors such as tree density, tree height, land use, legal standing, and ecological function. A forest is an area of land dominated by trees.
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