🌱 APES Topic 1.2: Terrestrial Biomes
A biome is a large geographic region on land defined by its climate, primarily average annual temperature and precipitation, and the distinct plant and animal life adapted to these conditions. A biome contains characteristic communities of plants and animals that result from (and are adapted to) its climate. Climate includes temperature and precipitation, which is often determined by latitude. Terrestrial biomes vary significantly from aquatic biomes.
Key terrestrial biomes are determined by factors such as temperature, precipitation, latitude, altitude, soil type, and disturbances like wildfire.
Global distribution of natural resources such as lumber and freshwater varies because of climate, geography, latitude and altitude, nutrient availability, and soil.
Major terrestrial biomes include:
Tundra: Very cold, short growing season, low precipitation (snow/ice), permafrost, low-growing plants.
Boreal Forest / Taiga: Cold winters, short summers, moderate precipitation, dominated by coniferous trees.
Temperate Rainforest: Moderate temperatures, high precipitation, large evergreen trees, abundant ferns and mosses.
Temperate Seasonal Forest: Moderate temperatures, distinct seasons, high precipitation, deciduous trees.
Grasslands: Moderate precipitation, hot summers, cold winters, dominated by grasses, fertile soils.
Savanna / Tropical Seasonal Forest: Warm year-round, distinct wet/dry seasons, grasses with scattered drought-tolerant trees.
Tropical Rainforest: Hot year-round, very high and frequent precipitation, extremely dense vegetation and high biodiversity, rapid nutrient cycling.
Desert: Very low precipitation, extreme temperature swings (hot days, cold nights), plants with water-saving adaptations.
Plants and animals in each biome show unique adaptations to survive their specific climate conditions. Biome distribution is generally predictable by latitude and altitude. Nutrient availability in soils is closely tied to decomposition rates, which vary with temperature and moisture.
Biomes are dynamic systems, with boundaries shifting due to climate change (e.g., warming leading to permafrost thaw) and human activities such as deforestation, agriculture, and altered fire regimes. The global distribution of biomes is not static - it has changed in the past and may change again as a result of current climatic trends.