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practice 38
created Mar 14th, 17:54 by Heartking001
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A significant challenge confronting engineers and scientists in developing
countries is the search for appropriate solutions to the collection, treatment,
and disposal or reuse of domestic waste. Technologies of waste collection
and treatment that have been taught to civil engineering students and
practiced by professional engineers for decades are, respectively, the water
borne sewerage and conventional waste treatment systems such as
activated sludge and trickling filter processes. However, the above systems
do not appear to be applicable or effective in solving sanitation and water
pollution problems in developing countries. Supporting evidence for the
above statement is the result of a World Health Organization report which
showed that in the year 2000 some 1.1 billion people did not have access to
improved water supply, and 2.4 billions were without access to any sort of
improved sanitation facility. For both the water supply and sanitation services,
the vast majority of those without access are in Asia. Although the
percentages of population served with adequate water supply and sanitation
increased during the past decade, due to rapid population and urban growth,
these percentages for the urban areas are not expected to increase much in
the next decade, while a lot of improvement is needed for the rural areas.
Sanitation conditions in both urban and rural areas need to be much
improved as large percentages of the population still and will lack these
facilities. Polprasert cited several reasons for the failure to provide sewerage
to the population of the cities of the developing countries. The construction of
sewerage systems implies large civil engineering projects with high
investment costs. Soil is the most important renewable natural resource. It is
the medium of plant growth and supports different types of living organisms
on the earth. The soil is a living system. It takes millions of years to form soil
upto a few cm in depth. Relief, parent rock or bed rock, climate, vegetation
and other forms of life and time are important factors in the formation of soil.
Various forces of nature such as change in temperature, actions of running
water, wind and glaciers, activities of decomposers etc. contribute to the
formation of soil. Chemical and organic changes which take place in the soil
are equally important. Soil also consists of organic and inorganic materials.
On the basis of the factors responsible for soil formation texture, age,
chemical and physical properties, the soils of India are classified in different
types
countries is the search for appropriate solutions to the collection, treatment,
and disposal or reuse of domestic waste. Technologies of waste collection
and treatment that have been taught to civil engineering students and
practiced by professional engineers for decades are, respectively, the water
borne sewerage and conventional waste treatment systems such as
activated sludge and trickling filter processes. However, the above systems
do not appear to be applicable or effective in solving sanitation and water
pollution problems in developing countries. Supporting evidence for the
above statement is the result of a World Health Organization report which
showed that in the year 2000 some 1.1 billion people did not have access to
improved water supply, and 2.4 billions were without access to any sort of
improved sanitation facility. For both the water supply and sanitation services,
the vast majority of those without access are in Asia. Although the
percentages of population served with adequate water supply and sanitation
increased during the past decade, due to rapid population and urban growth,
these percentages for the urban areas are not expected to increase much in
the next decade, while a lot of improvement is needed for the rural areas.
Sanitation conditions in both urban and rural areas need to be much
improved as large percentages of the population still and will lack these
facilities. Polprasert cited several reasons for the failure to provide sewerage
to the population of the cities of the developing countries. The construction of
sewerage systems implies large civil engineering projects with high
investment costs. Soil is the most important renewable natural resource. It is
the medium of plant growth and supports different types of living organisms
on the earth. The soil is a living system. It takes millions of years to form soil
upto a few cm in depth. Relief, parent rock or bed rock, climate, vegetation
and other forms of life and time are important factors in the formation of soil.
Various forces of nature such as change in temperature, actions of running
water, wind and glaciers, activities of decomposers etc. contribute to the
formation of soil. Chemical and organic changes which take place in the soil
are equally important. Soil also consists of organic and inorganic materials.
On the basis of the factors responsible for soil formation texture, age,
chemical and physical properties, the soils of India are classified in different
types
