Just like its climate, Earth’s land cover varies widely between regions. Some regions are characterized by deserts, while in others swamps predominate. Boreal forests, also called taiga, cover much of the planet’s northern latitudes, while tropical forests are a common feature in equatorial countries. These diverse types of land cover can be further broken down into “ecoregions”—large expanses of land, each with a distinct biological and environmental character.
Mapping land cover often involves defining a set of ecoregions and determining which part or parts of Earth’s surface match the criteria for each ecoregion. To define a set of ecoregions, scientists may supplement existing work, such as maps of species distribution and vegetation types, with new insights and data gathered from regional experts.
The land cover types included in this map layer are based on biogeographic research (sources listed here), a framework last updated in 2017 that defines more than 846 land-based ecoregions within about a dozen biomes or habitat types. This map layer represents those broader categories, like deserts and tropical forests. A couple of tips for navigating this layer: 1) If a region is shaded entirely in the color representing a particular biome, it indicates that that biome is the predominant one, but there may be characteristics of other biomes present as well. 2) The actual borders between biomes are often large regions unto themselves rather than precise lines. There’s even a name for these transition areas: ecotones!
This map layer from RESOLVE Biodiversity and Wildlife Solutions includes the following biomes:
Boreal Forests/Taiga: widespread in northern Russia and Canada, boreal forests are typically home to lots of conifers, mosses, and lichens
Deserts and Xeric Shrubland: the evaporation rate may be greater than the rate of precipitation in these dry regions exemplified by the Sahara and Gobi
Flooded Grasslands and Savannas: like mangroves, this biome is waterlogged land that may support grasses, shrubs, and trees; the Everglades of South Florida are an example
Mangroves: the mangrove tree dominates these coastal regions, which frequently lie within intertidal zones
Mediterranean Forests, Woodlands, and Scrub: these wooded regions are known for their hot, dry summers and cool, wet winters
Montane Grasslands and Shrublands: this biome, which features waxy, hairy plants, defines the Tibetan Plateau and parts of the Andes
Bare Earth: occurring largely in Earth’s polar regions, bare earth includes tundra, a type of cold desert with sparse vegetation
Temperate Broadleaf and Mixed Forests: this biome may include oak, beech, and maple trees; in contrast to tropical forests, biodiversity here is usually concentrated near the forest floor
Temperate Coniferous Forests: this biome has warm summers and cool winters with a wide variety of plant life including either needleleaf or broadleaf evergreen trees
Temperate Grasslands, Savannas, and Shrubland: trees are less common in this biome, which goes by many names—such as prairie, pampas, and veld
Tropical and Subtropical Coniferous Forests: located mostly in North and Central American regions with low precipitation and moderate temperature variability making it ideal for needleleaf conifers to grow
Tropical and Subtropical Dry Broadleaf Forests: this biome is characterized by year-round warm temperatures but seasonal precipitation that results in long dry periods and features drought-deciduous trees, for example, the forests of southern Mexico or central India
Tropical and Subtropical Grasslands, Savannas, and Shrublands: prominent in East Africa, these regions are often too dry to support much tree growth
Tropical and Subtropical Moist Broadleaf Forests: common in the region between the Tropics of Cancer and Capricorn, this biome has steady temperatures year-round and high precipitation allowing for evergreen and semi-evergreen trees
Tundra: found near the poles, this biome is characterized by a cold desert, dark winters, and sunny summers with low growing vegetation
