Environmental Engineering Reference
In-Depth Information
annual rate of deforestation between 1961 to 1986, dissolved oxygen in
rivers, faecal coliforms in rivers, municipal waste per capita and carbon
emissions per capita. The income data used were GDP per capita meas-
ured in 1985 US PPP. In order to overcome the comparability problem
of data across countries arising from dif erences in dei nitions and inac-
curate measurement sites, they applied a simple modelling technique, on
a consistent basis, to a large number of environmental quality indicators
and countries. They highlighted that there were four determinants af ect-
ing environmental quality in any given country. The determinants were
(1) climate and location, which was referred to as endowment, (2) per
capita income, which rel ected the production structure, urbanization and
consumption patterns of private goods, (3) exogenous factors, which were
available to all countries, but change over time, such as technology, and
(4) policies, which rel ected the social decisions af ecting the provision of
environmental public goods. Shai k and Bandyopadhyay in their study
focused on the relationship between per capita income and environmen-
tal quality, while taking into account the other determinants. The study
showed that some environmental indicators improved with higher income
per capita, such as water and sanitation, others worsened then improved,
such as particulates and sulphur oxides, and others deteriorated steadily,
such as dissolved oxygen in rivers, municipal solid wastes and carbon
emissions. For those environmental indicators that followed a bell-shaped
curve with rising income, the turning points varied. For instance, the
turning point for particulates was around $3280 per capita, while that of
sulphur oxides was around $3670 per capita.
Shai k (1994) concluded that individuals and countries tended to
address environmental problems at dif erent stages of economic develop-
ment depending on the relative costs and benei ts of the environmental
problem. For instance, water and sanitation were the i rst to be addressed,
given the relatively low costs and high private and social benei ts involved.
Local air pollution came next as it imposed external but local costs and
was relatively costly to abate, with high benei ts. They were also addressed
when countries reached a middle level of income where they became more
severe, as middle-income economies were often energy-intensive and
industrialized. Environmental problems that could be externalized, and
therefore, borne by poor or other countries, came last, such as solid wastes
and carbon emissions, as there were few incentives to bear the associ-
ated signii cant costs to abate. Moreover, the level of technology had a
positive impact on certain environmental quality indicators. If the costs
of degradation were localized, such as water sanitation and air pollution,
there would be high demand for improvements, and therefore technology
was crucial. However, where costs could be externalized and there was
