Environmental Engineering Reference
In-Depth Information
uncertain knowledge of their detrimental ef ects, such as carbon emissions,
there was little demand for technological improvements. Furthermore, he
highlighted that environmental improvements were not automatic. They
required ef ective environmental policies and investments to be put in
place to reduce environmental degradation.
Panayotou (1993) examined the relationship between nominal per
capita of GDP and four environmental indicators: SO
2
, NO
x
, SPM and
deforestation using cross-sectional data. The income data used were GDP
per capita in 1985 nominal US dollars. There were 54 countries in the pol-
lution sample and 68 in the deforestation sample and the three pollutants
were measured in terms of emissions per capita on a national basis. He
found evidence of EKC for the four indicators with turning points per
capita of around $823 for deforestation, $3000 for SO
2
, $5500 for NO
x
and
$4500 for SPM, measured in 1985 US dollars of nominal GDP. Panayotou
concluded that:
at low levels of development both the quantity and intensity of environmental
degradation are limited to the impacts of subsistence economic activity on the
resource base and to limited quantities of biodegradable wastes. As economic
development accelerates with the intensii cation of agriculture and other
resource extraction and the take of of industrialization, the rates of resource
depletion begin to exceed the rates of resource regeneration, and waste genera-
tion increases in quantity and toxicity. At higher levels of development, struc-
tural change towards information-intensive industries and services, coupled
with increased environmental awareness, enforcement of environmental regu-
lations, better technology and higher environmental expenditures, result in
levelling of and gradual decline of environmental degradation. (Panayotou,
1993, p. 1)
In another study on deforestation, Cropper and Grii ths (1994) exam-
ined the relationship between per capita income and the rate of deforesta-
tion in three regions: Africa, Latin America and Asia. They used pooled
cross-sectional and time series data for each region for the period 1961 to
1988. Their sample included 64 developing countries. They also examined
the ef ects of population pressure on deforestation, which they captured
by including the rural population density and the rate of population
growth as independent variables in their equation. They reported two
i ndings. First, an EKC relationship for both Africa and Latin America
with turning points of $4760 and $5420, respectively. These turning points
were higher than those found by Panayotou, possibly because of the use of
panel data. Second, the rural population density for Africa shifted the rela-
tionship between income and the rate of deforestation upwards. However,
none of the variables included for Asia were statistically signii cant. They
concluded that reducing the rate of population growth was not necessarily
