Biomes

Many different systems of classification, we will look at one that classifies 9 different biomes. Climate, temperature and precipitation will influence the type of vegetation.

Vegetation Larger the vegetation, the more water is needed  Forests = Areas with a lot of rain Grasslands = Areas with moderate rain Deserts???? Area with little rain...so smart ;)

Simple Diagram LOW TEMPERATURES MODERATE TEMPERATURES HIGH TEMPERATURES HIGH PRECIPITATION 1) Coniferous Forest (Boreal/Taiga) 2) Temperate Rainforest (Deciduous Forest) 3) Tropical Rainforest MODERATE PRECIPITATION 4) Tundra 5) Prairie Grassland (Temperate) 6) Tropical Grassland/Savannah 7) Mediterranean Chaparral LOW PRECIPITATION 8) Cold Desert 8) Temperate Desert 8) Tropical Desert

Major Biomes of the World

1) Coniferous/Boreal/Taiga Forest -the largest biome by area

Climate Northern Hemisphere, humid continental climate (Warm summer, cold winter) Fog and snow are common Because there is not a lot of sunshine, there is not much evaporation so there is enough water to support trees.

Vegetation Cone-bearing trees with needles such as pine, spruce, fir and cedar. Needles can cause soil to be acidic; few plants grown under trees. The thinness of the soil is due largely to the cold, which hinders the development of soil and the ease with which plants can use its nutrients.

Adaptations Microtherms – vegetation survives in cold temperatures – thick bark. Shallow root system Flexible branches causes snow to fall off and winds not to break branches. Cones protect seeds from cold temperatures Waxy needles minimize transpiration.

Human Activities Deforestation from logging. Mining. Urbanization. Recreational value: hiking, camping, hunting.

2a) Temperate Rainforest Coastal non-tropical regions Coniferous trees are taller because of more precipitation. More growth under the trees because of less acidity of soil.

2b) Temperate Deciduous Forest East Coasts of North America, Asia and Europe. Trees lose their leaves in winter to save water and energy. Agriculture and Urbanization are threats to this biome.

Deciduous Forests

3) Tropical Rainforest Low Pressure belt of equator – high temperatures and high precipitation throughout the year – year round growing. The most diverse biome in the world

Vegetation: Megatherms – Require constant heat. A tall “canopy” of broad leaf evergreen trees An “understory” of smaller trees, bushes. A “ground cover” of ferns and other plants.

Adaptations Buttress Roots to support large trees. Lianas/Vines climb up to reach sunlight. Shallow roots due to leaching of soil. Evergreen to maximize photosynthesis. Tall canopy to compete for sunlight. Animals: most live in canopy (monkeys, frogs, butterflies, birds, etc…)

Human Activities Mining Deforestation for… Hardwoods (teak, mahogany) Population resettlement (urbanization) “Cash Crop” Plantation agriculture (bananas, coffee, coconuts, sugar, rubber, etc.) Grazing animals for N. American beef market

4) Tundra Long winters, short summers No trees Only mosses, lichens Permafrost prevents melted snow from reaching soil causes small lakes to cover landscape Adaptations: White colour for animals Low growing to protect from cold

Human Activities Mineral extraction Hunting of big game (large animals)

5) Tropical Grasslands (Savannah) Tropical/ Savannah 

Vegetation Wet/dry seasons. Not many trees, but some. Tall grasses Xerophytes (Cactuses- drought-loving). These plants have thick skins and are adapted to live in areas with little precipitation

Adaptations Grasses grow quickly during precipitation Lots of shallow roots to absorb water quickly. Long roots to reach groundwater. Vegetation widely spaced to avoid competing for moisture. Thick waxy leaves with thorns to prevent transpiration. Thick bark to protect from heat and wildfire. Trees have flat tops to create shade.

Human Activities Wildlife viewing (safaris tourism) Fire Deforestation for fuel Desertification Over grazing of animals

6) Prairie Grasslands (Temperate) Prairie regions in Canada. Also called steppe, pampas or veld. Less hot than tropical

Vegetation Grasses Sparse trees, usually along rivers. Adaptations: Grasses grow quickly during precipitation Lots of shallow roots to absorb water quickly. Long roots to reach groundwater.

Human Activities Prairie Fires are a natural threat. Agriculture, especially cereal crops such as wheat. Grazing livestock (animals) In Mongolia this leads to desertification. In Alberta, mineral extraction threatens the biome.

7) Mediterranean/Chaparral Small scattered trees and thorny bushes Sclerophyll: Type of plant that has adapted to the biome Long root systems and thick bark Plants have essential oils, which lead to wildfires which threaten humans Good area for agriculture because of richness of soil and moderate temperatures.

8) Deserts Tropical, Temperate and Cold types Xerophytes Cactus – Store water, deep root system and shallow roots. Thick waxy leaves to prevent transpiration

Human Activities Agriculture where water is available Over grazing Desertification