Geography Reference
In-Depth Information
The
ecological footprint
is another tool for allowing people
to understand the wider impact they have on the environment
through the activities they undertake and the products they
consume. It is similar to the carbon footprint discussed in Chapter
2. The ecological footprint estimates the amount of ecological
resources that are used by individuals, companies or countries. It is
a measure of the amount of biologically productive area needed to
both produce resources used and to absorb waste created by an
activity or in the creation of a purchased product. Most developed
countries appear to be using more resources than they can sustain
and are therefore running at an ecological deficit. It was estimated
in 2010 by the Global Footprint Network that it takes the Earth 17
months to regenerate what we currently use in 12 months. The
measure can be used to set goals for reducing consumption (recy-
cling, wind power etc.) or increasing ecological productivity (for
example, roof gardens).
SUMMARY
• Light, temperature, moisture availability, geological factors,
humans and biotic factors such as competition, adaptation and
migration all result in differences across the biosphere.
• Ecosystemsaredynamicwithinputsofenergy,cyclesofnutri-
ents and changes through time.
• Thecoldbiomesofthetundraandtaigahavelowproductivity
and vegetation is slow-growing restricted by short growing
seasons. Irregular fire is a feature helping to regenerate and
increase productivity in the taiga.
• Thetemperatebiomesofthedeciduousforest,evergreenforest,
Mediterranean chaparral, and temperate grasslands are domi-
nated by seasonality, with the latter two showing more adapta-
tions to fire.
• Themainbiomesinthetropicsarethehighlyproductiveand
diverse tropical forests, the lower productivity savanna and the
low productivity hot deserts. Savanna species often show adap-
tation to regular fire.
• Humanshavehadamajorimpactonthebiospherebyreducing
biodiversity through deforestation, agriculture, overexploitation
of species and other environmental damage.
