A vegetation zone is a large area of land where climate conditions produce a distinct, recognizable type of plant life. Tropical rainforests, grasslands, deserts, and boreal forests are all examples. The boundaries of these zones are shaped primarily by temperature and precipitation, which together determine what can grow in a given place.
The concept is straightforward: travel far enough north, south, or up a mountainside, and the plants around you will change in predictable ways. Those transitions mark the edges of different vegetation zones.
How Climate Draws the Lines
Temperature and rainfall are the two biggest factors controlling which plants dominate a landscape. Hot, wet conditions near the equator support dense broadleaf forests. Hot, seasonally dry conditions produce savannas, where scattered trees sit above a continuous layer of tall grass. Cold, dry conditions at high latitudes give rise to treeless tundra. Between these extremes, you get temperate forests, steppes (dry grassy plains), and scrublands, each reflecting a particular balance of warmth and moisture.
Soil plays a supporting role. In the Arctic, permafrost keeps the ground frozen year-round, and only a shallow surface layer thaws during summer, limiting plant roots to dwarf shrubs and herbs. In the wet tropics, iron-rich soils called ferralsols develop on well-drained land, while sandy, nutrient-poor soils in the same latitude can shift the vegetation toward entirely different species. Boreal and temperate forests often sit on acidic soils known as podzols, which form under coniferous trees and heather in humid conditions.
These factors interact. A region with enough rainfall to support forest might instead be grassland if its soils drain too quickly or its winters are too harsh. That interplay is why vegetation zones don’t follow neat latitude lines on a map.
The Major Zones Around the World
Vegetation zones repeat wherever similar climates exist, even on different continents. The actual species differ, but the overall structure of the plant community looks remarkably similar. Chaparral, the dense, drought-adapted shrubland found in southern California, also appears in Chile, Spain, Italy, southwestern Australia, and the tips of Africa. The plants are different species, but they’ve evolved the same forms in response to the same climate pattern: mild, wet winters and hot, dry summers.
The broadest categories include:
- Tropical rainforest: One of the largest zones on Earth, dominated by broadleaf trees forming a dense upper canopy with extraordinary biodiversity beneath it. Found near the equator in South America, Central Africa, and Southeast Asia.
- Tropical savanna: Open tree canopy over continuous tall grass, shaped by hot conditions with a pronounced dry season. The East African savannas are the classic example.
- Desert and semi-desert: Sparse, drought-resistant vegetation in areas receiving very little rainfall, such as the Sahara, the Arabian Peninsula, and interior Australia.
- Steppe and grassland: Dry, grassy plains with few or no trees. The Eurasian steppe, the North American Great Plains, and the Argentine Pampas all fit this category.
- Temperate forest: Deciduous or mixed forests in regions with moderate rainfall and distinct seasons, including much of eastern North America, Western Europe, and parts of East Asia.
- Boreal forest (taiga): Vast coniferous forests stretching across northern Russia, Scandinavia, and Canada, dominated by spruce, pine, and fir.
- Tundra: Treeless landscapes at the highest latitudes or altitudes, with only low shrubs, mosses, and lichens surviving the short growing season.
Vegetation Zones on Mountains
You don’t have to travel thousands of kilometers to cross vegetation zones. Climbing a single mountain can take you through several in a matter of hours. Temperature drops roughly 6.5°C for every 1,000 meters of elevation gain, so a mountain in the tropics might have rainforest at its base, cloud forest partway up, alpine meadows higher still, and bare rock or ice at the summit.
This vertical pattern is called altitudinal zonation, and it has fascinated scientists for centuries. The transitions, however, aren’t as tidy as textbook diagrams suggest. USDA Forest Service research in the northern Rocky Mountains has shown that local topography can override elevation entirely. Cold air pools in valleys, creating frost pockets where high-elevation species grow at surprisingly low altitudes. Meanwhile, warm, south-facing slopes can push lowland species hundreds of meters higher than expected. One study in Idaho found that the same tree species occurred at elevations ranging from 863 to 1,158 meters on one mountainside, while grassland steppe dominated at the same elevation just 25 kilometers to the west.
The lesson: elevation is a useful shorthand, but the actual vegetation zone at any point depends on slope direction, drainage, cold air movement, and dozens of other local factors.
How Vegetation Zones Differ From Biomes
You’ll often see “vegetation zone” and “biome” used interchangeably, and for everyday purposes they overlap heavily. But they aren’t quite the same thing. A biome is defined by the structure and function of its ecosystem, including animal life, not just its plants. Biomes are identified by the life forms of their dominant organisms rather than by specific species. So “tropical rainforest” is both a vegetation zone (defined by its plant community) and a biome (defined by the full ecosystem).
An ecozone is broader still. Ecozones are large-scale divisions of the Earth’s surface based on evolutionary history, separated by barriers like oceans, deserts, or mountain ranges that have kept organisms evolving in relative isolation. A single ecozone can contain several biomes. Think of it as a nesting system: ecozones contain biomes, and biomes are closely tied to vegetation zones. In practice, “vegetation zone” is the most intuitive of the three terms because it describes exactly what you’d notice walking through a landscape: the plants changed, so you’ve entered a different zone.
How Climate Change Is Shifting the Boundaries
Vegetation zones are not fixed. As global temperatures rise, these boundaries are migrating, generally toward the poles and uphill. A 2025 study in Oregon projected that by 2041 to 2070, 63% of the state’s landscape will shift to climate conditions associated with a different vegetation zone than the one currently there.
The projected changes are dramatic. Conifer-dominated forests, which currently cover about 64% of Oregon’s study area, are expected to shrink to just 27%. Shrublands would expand from 33% to 46% of the landscape, and grasslands from 0.5% to 3.1%. Cold forests and high-elevation parklands are projected to nearly disappear, replaced by warmer, drier forest types. Several specific forest types, including lodgepole pine and subalpine fir, face reductions of more than 90%.
The speed of these changes matters. The study estimated that climate conditions are shifting at roughly 3 kilometers per year, which is faster than many plant species can naturally disperse their seeds to new territory. That mismatch means some vegetation zones won’t simply migrate; the plants that define them may not be able to keep up.
Human Activity and Fragmented Zones
Climate isn’t the only force redrawing vegetation zones. Urbanization and agriculture have directly replaced or fragmented natural plant communities across much of the planet. Converting land to urban use is one of the most irreversible changes humans impose on a landscape: it eliminates vegetation biomass, fragments habitats, and alters local water and nutrient cycles.
The cascading effects compound the damage. As cities expand onto productive farmland, agriculture pushes outward into previously natural areas. Research from India and China shows that agricultural land loss around cities drives farming into new territory, putting pressure on whatever vegetation zone sits at the frontier. In India, this agricultural displacement is happening more around smaller cities than major urban centers, spreading the impact across wider areas. In the tropics, the direct loss of plant biomass from likely urban expansion zones is projected to contribute about 5% of total emissions from tropical deforestation and land-use change.
The result is that many of the world’s vegetation zones no longer exist as continuous bands on the map. They persist as patchwork fragments, with roads, farms, and cities breaking up what were once seamless transitions from one zone to the next.