1.1 – Biomes and Earth’s Spheres
 an ecosystem is the term used for the interaction between
living and non-living things in a set area
o ecosystems come in all sizes
o ecosystems combine to make biomes
biome = large geographic regions that contain similar
ecosystems
 there are 5 main terrestrial (land) biomes in Canada:
o tundra  far North
o mountain (aka coniferous) forest  western Canada
o grasslands  Prairies
o boreal forest  spans all across Canada
o temperate deciduous forest  southern Ontario
 there are 2 main aquatic (water) biomes in Canada:
o marine  oceans
o freshwater  lakes, streams, ponds, rivers, wetlands
 biomes combine to make up the 4 major spheres on Earth:
i. biosphere = the part of the Earth where living things
exist
ii. lithosphere = the hard part of the Earth’s surface
(ex: stones, rocks, mountains)
iii. hydrosphere = the part of the Earth that is water
(includes salt and fresh, water vapour)
iv. atmosphere = the layer of air above the Earth’s
surface (gases)
Biosphere
 Earth is the only planet with a biosphere that we know of
 this is the sphere that interacts the most with the other 3
(is not distinct from the other 3 spheres)
Illustrating the interconnectedness of the 4 spheres:
The water cycle
 Sun’s rays evaporate huge amounts of water from oceans
and other bodies of water within the hydrosphere
 as water vapour rises in the atmosphere, it cools and
condenses, forming clouds
 eventually the water falls back to the lithosphere as
precipitation (liquid or solid)
 as water returns to the oceans by river systems, it erodes
rocks and picks up other materials (nutrients, minerals)
 it’s absorbed by plants in the biosphere so they can
undergo photosynthesis
 it’s consumed by animals in the biosphere
 water plays a critical role in the survival of animals (cell
respiration, body cooling, hydration, etc.)
 without water, the biosphere couldn’t exist!