The distribution of biomes is largely a result of the Earth’s tilt and atmospheric circulation. The Climatograph is the essential tool for identifying biomes, plotting monthly average temperature and precipitation. Terrestrial biomes are defined by these abiotic factors that dictate the plant and animal adaptations found within each region, along with soil quality and primary productivity rate.

Tundra

The Tundra is a cold, dry biome characterized by permafrost (soil or rock that remains frozen from one year to the next). This cold desert has low net primary productivity and a very short growing season, supporting only mosses, lichens, and small shrubs. As the global temperature rises, the melting permafrost creates a positive feedback loop by releasing methane (CH4), a greenhouse gas, into the atmosphere.

Taiga (Boreal Forest)

The Boreal Forest consists of cold winters and short growing seasons dominated by coniferous trees. These trees have needle-like leaves to reduce water loss and shed snow easily. The soil is acidic and nutrient-poor because the cold climate slows the decomposition of fallen needles, keeping organic matter locked in the leaf litter.

Temperate Rainforest

Temperate rainforests are found in coastal regions. They feature moderate temperatures and very high precipitation. The constant moisture supports massive trees like Redwoods, but the heavy rainfall often leaches nutrients from the soil, making it less fertile than other temperate forests. It is characterized by high biomass and frequent coastal fog.

Temperate Seasonal Rainforest

Temperate seasonal rainforest is a biome that experiences four distinct seasons and moderate precipitation. This biome is dominated by deciduous trees that drop their leaves in winter to conserve water. The rapid decomposition of this organic matter creates highly fertile soil. Consequently, much of this biome has been cleared for human settlement and industrial agriculture.

Shrubland

Also known as woodland or chaparral, shrubland is defined by hot, dry summers and mild, rainy winters. It is a biome adapted to fire. Many plants in this biome have leathery leaves to prevent water loss and produce seeds that require the heat of a fire to germinate. The soil is nutrient-poor due to nitrogen leaching during the winter, and this biome is increasingly threatened by human-induced wildfires.

Temperate Grassland

Temperate grassland is a biome characterized with hot summers, cold winters, and moderate precipitation. This biome is dominated by grasses rather than trees. It possesses the most fertile soil on Earth thanks to the rapid growth and decay of deep grass roots. Frequently converted into “breadbaskets” for grain production, these areas are maintained by periodic fire and grazing.

Tropical Rainforest

Tropical rainforest is located near the equator. It is a biome that has the highest net primary productivity and biodiversity due to constant heat and rain. However, the soil in this biome is extremely nutrient-poor because plants here absorb nutrients almost instantly after decomposition. Adaptations include broad leaves for sunlight capture and buttress roots for stability in shallow soil.

Savanna

Also known as tropical seasonal forest, the savanna features warm temperatures with distinct wet and dry seasons. It is characterized by vast grasslands and drought-deciduous trees that drop leaves during the dry season to save water. While this biome is more fertile compared to the rainforest, it is highly susceptible to desertification from overgrazing.

Desert

Deserts is a biome that has dry air and receive less than 25 cm of rain annually. This biome has the lowest net primary productivity of all terrestrial ecosystems. Because the metabolic rate is extremely slow, deserts take centuries to recover from human disturbance.