Terrestrial biomes

Geographical zonation

Climatic zonation

Geo-climatic interactions

• Temperature more significant near poles
• Precipitation more significant near equator

Ten terrestrial biomes

1. Tundra (arctic and alpine)
2. Boreal forest
3. Temperate rain forest
4. Temperate deciduous forest
5. Temperate grassland
6. Chaparral
7. Desert
8. Tropical rain forest
9. Savanna
10. Mixed montane

Eight zoogeographical regions

1. Afrotropical
2. Antarctic
3. Australian
4. Indomalayan
5. Nearctic
6. Neotropical
7. Oceanian
8. Palearctic

Spatial distribution of terrestrial biomes and zoogeographical regions

Features to note

• Geographic range
• Seasonality
• Annual Precipitation
• Average Monthly Temperature Range
• Soil nutrients/acidity
• Predominant vegetation
• Species richness
• NPP (percent of terrestrial/freshwater total)
• Primary threats

Tundra

Tundra

Range:	Extreme northern latitudes
Seasons:	Long, harsh winters and short summers
Precipitation:	10-25 cm
Temperature:	$-30$- $15^{\circ}\text{C}$
Soil:	Low nutrient content
Vegetation:	Mosses, lichens, grasses, sedges
SR:	Low
Productivity:	1%
Threats:	Fossil-fuel exploration, climate change

Boreal forest (taiga)

Boreal forest (taiga)

Range:	South of tundra
Seasons:	Long winters and short summers
Precipitation:	50 cm
Temperature:	$-25$- $15^{\circ}\text{C}$
Soil:	Acidic, low mineral content
Vegetation:	Conifers, occasional deciduous stands
SR:	Moderate
Productivity:	9%
Threats:	Logging, mining

Temperate rain forest

Temperate rain forest

Range:	Northwest coast of North America, southern South America, southeastern Australia
Seasons:	Mild winters and cool summers
Precipitation:	127 cm
Temperature:	$5$- $20^{\circ}\text{C}$
Soil:	Low nutrient content, high organic content
Vegetation:	Conifers, epiphytes
SR:	Very high
Productivity:	6%
Threats:	Logging

Temperate deciduous forest

Temperate deciduous forest

Range:	Temperate regions
Seasons:	Cold winters and hot summers
Precipitation:	75-150 cm
Temperature:	$4$- $28^{\circ}\text{C}$
Soil:	High nutrient content, high organic content
Vegetation:	Broad-leaved hardwoods, broad-leaved evergreens in southern forests
SR:	High
Productivity:	8%
Threats:	Logging, agriculture, plantation forestry

Temperate grassland

Temperate grassland

Range:	Temperate regions
Seasons:	Cold winters and hot summers
Precipitation:	25-75 cm
Temperature:	$0$- $28^{\circ}\text{C}$
Soil:	High nutrient content, high organic content
Vegetation:	Grasses
SR:	Moderate (large numbers of threatened/endemics)
Productivity:	4%
Threats:	Agriculture, overgrazing

Chaparral

Chaparral

Range:	Mediterranean region, North American Southwest, southwestern and southern Australia, central Chile, southwestern South Africa
Seasons:	Mild winters and hot summers
Precipitation:	Abundant in winter, absent in summer
Temperature:	$15$- $25^{\circ}\text{C}$
Soil:	Thin, low nutrient content
Vegetation:	Evergreen shrubs
SR:	Moderate-low
Productivity:	5%
Threats:	Fire suppression, vegetation removal

Desert

Desert

Range:	Temperate (cold deserts) and subtropical (hot deserts) regions
Seasons:	Hot deserts consistently hot, cold deserts vary, both undergo daily extremes
Precipitation:	$<25$ cm
Temperature:	$0$- $20^{\circ}\text{C}$
Soil:	Low organic content, high mineral content
Vegetation:	Cacti, scrub
SR:	Low
Productivity:	1.2%
Threats:	Recreation, poaching, development, aquifer depletion

Savanna

Savanna

Range:	Tropical regions; Africa, South America, northern Australia
Seasons:	Predominantly driven by precipitation rather than temperature
Precipitation:	76-150 cm, highly seasonal
Temperature:	$16$- $24^{\circ}\text{C}$
Soil:	Low nutrient content
Vegetation:	Grass, occasional trees
SR:	Charismatic megafauna
Productivity:	10%
Threats:	Agriculture, overgrazing, rangeland

Savanna

Savanna

Savanna

Tropical rain forest

Tropical rain forest

Range:	Tropical regions; Latin America, Sub-Saharan Africa, Southeast Asia
Seasons:	Little variation
Precipitation:	200-450 cm, consistent
Temperature:	$25$- $27^{\circ}\text{C}$
Soil:	Low nutrient content, nutrients in vegetation
Vegetation:	Broad-leaved deciduous trees, epiphytes, lianas
SR:	Highest levels for terrestrial biomes
Productivity:	32%
Threats:	Agriculture, logging

Canopy structure

Tropical rainforest

Tropical rainforest

[allowframebreaks] References