Environmental Engineering Reference
In-Depth Information
countries would be able to follow an income-pollution path similar to that
of the developed countries as the demand of the developed countries for
pollution-intensive products was being met by the developing countries.
Therefore, the developing countries did not have anyone to pass on the
production of such products to.
The role of population density
In the economic-growth-environment literature, there are a number of
empirical studies that included population density variables as it is per-
ceived that population density af ects the relationship between income
and the environment. As mentioned earlier, Cropper and Grii ths (1994)
examined the ef ects of population pressure on deforestation by including
the rural population density and the rate of population growth as inde-
pendent variables in their equation. They found an EKC relationship for
both Africa and Latin America with turning points of $4760 and $5420,
respectively. They found that the higher the rural population density, the
higher the deforestation rate. An increase in rural population density by
100 persons per 1000 hectares implied an increase of the deforestation rate
by 0.33 per cent in Africa. However, none of the variables included for Asia
were statistically signii cant. The authors also found that the rural popu-
lation density for Africa shifted the relationship between income and the
rate of deforestation upwards, which implied the existence of a large trade-
of between per capita income and rural population density. For instance,
a country with a population density of 0.1 persons per hectare, being the
average population density for the sample of African countries, had a peak
deforestation rate of 1.26 per cent per year at a per capita income level of
$4760. For a country with a population density of 0.7 persons per hectare,
it would need a per capita income level of $11 650 per year to achieve the
same deforestation rate. Nevertheless, the authors concluded that defor-
estation was the problem of market failure, which resulted from the lack
of dei ning and enforcing property rights. Therefore, reducing the rate of
population growth was not necessarily the best method for reducing the
rate of deforestation in developing countries.
Also as mentioned earlier, Panayotou (1997) explored the role of popu-
lation density using two approaches: the reduced-form analysis and the
income decomposition analysis with its three constituents, scale, composi-
tion and abatement. Under the reduced-form approach, Panayotou found
an inverted U-shaped relationship with a per capita turning point of just
under $5000. However, he found that the higher the population density, the
higher the level of ambient SO
2
at every income level. With respect to the
decomposition approach, the author found that, controlling for all other
factors, low levels of population density of under 50 persons per square
