Chapter 7. Biomes, Soils and Ecosystems
A biome is a large region with characteristic climate, vegetation and animal life [4].
| Biome | Typical climate | Features |
| Tropical rainforest | Hot, wet all year | Highest biodiversity (Amazon, Congo, Southeast Asia) |
| Savanna | Warm, with wet and dry seasons | Grasses with scattered trees (East Africa) |
| Desert | Very dry | Sparse, drought-adapted life |
| Mediterranean scrub | Dry summers, mild wet winters | Hardy shrubs |
| Temperate forest and grassland | Moderate rainfall, four seasons | Deciduous forest, prairies, steppes |
| Boreal forest (taiga) | Long cold winters | Conifers, the largest forest biome |
| Tundra | Very cold, permafrost | Mosses, lichens, low shrubs |
Soils form from parent rock, climate, living organisms, relief and time. Fertile soils such as the grassland mollisols support the world’s major grain regions, while heavily leached tropical soils are often nutrient-poor despite lush vegetation [4].
Biodiversity is threatened by habitat loss, overexploitation, pollution, invasive species and climate change [14][16].
Review: Why can a tropical rainforest soil be poor even though the forest above it is so productive?