Biomes – part 2 Terrestrial biomes

Factors to consider : temperature and precipitation Determine which plant species can live in the environment The plants then dictate which animal species can live there Different terrestrial biomes include: 1. Tropical forests 2. Boreal forests 3. Temperate forests 4. Grasslands and shrublands 5. Artic tundra 6. Deserts 7. alpine biomes

Tropical forests  Located near the equator  Temperature range 20-34˚C  Forests can be seasonal or evergreen  Seasonal : rainy and dry season, Africa  Evergreen : rainforest, no dry season, South America and Asia

Tropical rain forests  Occupy less than 10% of earth’s land mass  Provide habitat for 50 to 80% of terrestrial plant and animal species  Major damage has been done to the rainforests in the past 30 years due to clear cutting and burning  Rainforests can help regulate climate change

Boreal forests  Boreal – borealis, which mean North  Cover large part of Canada and northern Russia  Composed of conifers, forest floors of moss and lichen  Nutrient poor soil  Many lakes and marshes also found  Human disturbance is greatest threat

lichen

Boreal forests : world map

Temperate forests  Southern Canada, US, Europe, part of Asia  In Canada :mix of conifers and deciduous trees  Further south: mostly deciduous trees  Nutrient rich soil : decomposing leaves causes rapid plant growth and a dense multi-layered forest  Plants/grass/moss, bushes, trees

The rich vegetation of the temperate forests provides the perfect habitat for black bears, squirrels and raccoons

Temperate forests : disturbances  Largely destroyed by human activity  Montreal and Toronto were once temperate forests  Forests cleared for farmland

Grasslands and shrublands  The prairies  Enough rainfall to avoid desertification but not enough for trees to grow  Temperate grasslands : hot summer, long cold winter  Savannas: tropical or subtropical, hot year round  Derived grasslands: artificial fields of grass, farmland 90% of prairies are farms now

Temperate grasslands Savannas Derived grasslands

Arctic tundra  North of the boreal forests  Tundra : treeless land  6% of world’s land mass  Consists of grasses, stunted bushes, moss, lichen  Long cold winters, very short summers  Slow plant growth  Ground does not thaw completely (permafrost)

Artic tundra (continued) Many migratory birds spend the summers here Caribou, arctic foxes and lemmings live year round Climate change is putting this biome at great risk, the arctic is warming up twice as fast as the global average

Deserts  1/3 of the earth’s land mass  Low precipitation, extreme temperatures  Found at all latitudes  Cold deserts, hot deserts, sand deserts and stone deserts  Less than 25 cm of precipitation  Temp extremes -89˚C in Antarctica and +52.5˚C in Thar desert Asia

Deserts  Rare plant life  Few animals, highly adapted to desert life  Sahara desert : largest in world  Temp range – day time very hot and dry and at night it can get down to 0˚C  No humidity or clouds to trap the sun’s heat

Alpine biomes  Defined by altitude not latitude  Rocky mountains, Andes, Himalayas  Higher altitude = lower temperature  Creates vegetation zones  Deciduous, conifers, tundra, snowy desert