|We've heard and
read, this summer, that carbon dioxide is a pollutant gas. Alberta's Bill 32,
introduced Tuesday, identities it as a natural resource.
is essential to life. Plants absorb it from the atmosphere and incorporate
the carbon component in their growing structure. Animals use plant material
as fuel and release the carbon content as carbon dioxide.
cycle diagram establishes the sheer magnitude of the carbon cycle.
|Note that plants
absorb about 120 billion tonnes of carbon from 440 billion tonnes of
atmospheric carbon dioxide annually. A similar amount is released by decay,
fires and food consumption by animals.
|Human use of
fossil fuels releases about 5.5 billion tonnes of carbon to the atmosphere as
20 billion tonnes of carbon dioxide.