Geography Reference
In-Depth Information
for sequestering CO
2
in ocean and land biomass. On the demand side, we evaluate
the record of harvests for human consumption (fishing, forestry, crops, grazing
lands, etc.), the removal of land from productive inventory for construction,
environmental degradation through production of waste, and in particular, the
production of CO
2
emissions through the combustion of fossil fuels. The results are
expressed in units of surface area using formulas built on equivalencies. The
calculations supposedly conform to the laws of thermodynamics and are consistent
with the principles of ecology. Unfortunately, the indicator is imperfect since
calculations are complex and equivalencies controversial, such that the scientific
controversy relating to the various environmental parameters has produced a
proliferation of accounting methods which not only do not agree but frequently
obscure the debate.
Whatever the relevance of figures advanced here and there, one cannot deny that
the ecological footprint of the United States far exceeds their national resources. The
excess of consumption over the natural capacity for regeneration is not sustainable
over the long term (overshooting), as it entails drawing on the natural wealth of the
land, thus reducing its ability to support the development of future generations. Such
overshooting contributes heavily to the production of greenhouse gases. The
arguments are quite convincing and many environmental NGOs have adopted this
accounting.
According to the Global Footprint Network created by Wackernagel [EWI 08],
in 2005, biologically productive surfaces available per inhabitant amounted to less
than 1.6 hectare-equivalents of dry land and 0.5 hectare-equivalents of ocean
surfaces, mainly located on continental shelves. To ensure sustainable development
and the preservation of biodiversity, humanity should reserve at least 12% of
available surface areas for other species. These lands should be classified as
protected areas and set aside as nature reserves, out of reach of human activity. At
least, this is the recommendation of the Brundtland Report [BRU 87]. Biologists
however, go further and suggest that fully a third of biologically productive areas
should be protected. With acceptance in principle and agreement on accounting
methodologies, a general scheme may be broken down by country, region, city and
even household.
The largest countries by surface area naturally have the greatest advantage,
provided that the surface area is not desert land (see Table 10.1). Biological
productivity is also higher in hotter regions than in colder regions. Thus, by
Wackernagel's accounting, the United States are the most productive biotope before
Brazil.
