environmental engineering

1. Environmental Engineering
(Main Considerations)
Feb. 2023

2. Environmental Main Issues
Environmental issues are:
• The harmful effects of human activities on the environment; these
include pollution, overpopulation, waste disposal, climate change,
global warming, the greenhouse effect, etc.
• Various environment protection programs are being practiced at the
individual, organizational and government levels with the aim of
establishing a balance between man and the environment.

3. Main Solutions/Strategies
• Prevention is always better than cure; that is why we plead for
prevention and control of environmental pollution;
• Replace disposal items with reusable items;
• The use of paper should be avoided;
• Conserve water and electricity (e.g. fossil fuels);
• Support environmental friendly practices;

4. Contd..
• Recycle waste to conserve natural resources;
• Control the increase of human population;
• Reduction in consumption of the natural resources (e.g. the use
of paper should be avoided);
• Support environmental friendly practices;
• Recycle waste to conserve natural resources.

5. Environment!
• Non-living component: Atmosphere + Hydrosphere + Lithosphere
• Living component: Biosphere (Human, Plants, Animal, etc.)

6. Atmosphere
• Troposphere;
• Stratosphere;
• Mesosphere;
• Thermosphere;
• Exosphere.

7. Layers of the Atmosphere

8. Troposphere
• The troposphere is the lowest layer of Earth's atmosphere.
• Most of the mass (about 75-80%) of the atmosphere is in the
troposphere.
• Most types of clouds are found in the troposphere, and almost
all weather occurs within this layer.

9. Stratosphere
• The stratosphere extends from the top of the troposphere to
about 50 km above the ground.
• The infamous ozone layer is found within the stratosphere.
• Unlike the troposphere, the stratosphere actually gets warmer
the higher you go!

10. Mesosphere
• Above the stratosphere is the mesosphere.
• It extends upward to a height of about 85 km above our planet.
• Unlike the stratosphere, temperatures once again grow colder as you
rise up through the mesosphere.
• The coldest temperatures in Earth's atmosphere, about -90° C are
found near the top of this layer.
• The air in the mesosphere is far too thin to breathe.

11. Thermosphere
• The layer of very rare air above the mesosphere is called the
thermosphere.
• High-energy X-rays and UV radiation from the sun are absorbed
in the thermosphere, raising its temperature to hundreds of
degrees.

12. Exosphere
• Some scientists consider the thermosphere to be the uppermost
layer of our atmosphere, others consider the exosphere to be
the actual final frontier of Earth's gaseous envelope.
• The air in the exosphere is very thin, making this layer even
more space-like than the thermosphere!

13. Hydrosphere
• A hydrosphere is the total amount of water on a planet
• The hydrosphere includes water that is on the surface of
the planet, underground, and in the air.

14. Total water on earth
• Saltwater: %97
• Polar ice: %2.3
• Fresh water: %0.7
 Underground fresh water: %0.66
 Fresh water in rivers and lakes: %0.03

15. Lithosphere
• It includes the soil which covers the rock's coating in many places;
• Rocks are subjected to continuous weathering forces rain, wind,
chemical and biological and suffer disintegration;
• A typical soil, suitable for agriculture, contains about %5 organic matter
and %95 inorganic matter.

16. Biosphere
• The biosphere is a global ecosystem composed of living organisms;
• The biosphere consists of the earth’s coating, hydrosphere, atmosphere
and various living species (micro-organisms to man);
• Both biosphere and environment have close interactions with each
other.

17. Pollution and Pollutants
The phenomenon of pollution is the external substances that
effect on properties of air, water and soil which known as
pollutants.
• Types of pollution:
Air pollution;
Water pollution;
Land pollution;
Noise pollution;
Radioactive pollution.

18. Pollutants - Natural and man-made
Sources
• Natural sources of air pollution are: volcanic activity,
vegetation deterioration, forest fires releasing carbon
monoxide;
• Man-made sources of air pollution are: gases, fogs,
particles and aerosols released by industries;
• Natural sources of water pollution are: soil erosion,
particles from atmosphere, vegetation deterioration etc.
• Man-made sources of water pollution are: domestic and
industrial sewage, agricultural run-off, radioactive wastes, oil
pollution, pesticides etc.

19. Ecosystem
• Ecology The study of living organisms, it deals with species,
organisms, populations, communities and biosphere;
• Population is defined as a group of individuals of any kind of organisms
• Community includes all the populations of a given area, called the
habitat;
• Community and the abiotic environment interact refer to the
ecological system or the ecosystem.

20. Classification of Ecology
1. Autecology:
• It is associated with the ecology of an individual species and its
population.
• It is also called species ecology
2. Synecology:
• It is the study of communities and divided into three fields
• Population ecology
• Community ecology
• Ecosystem ecology

21. Contd.
3. Classification on the Basis of Habitat
I. Aquatic ecology
a. Marine ecology
b. Freshwater ecology
c. Stream ecology
II.Terrestrial ecology
a. Grassland ecology
b. Forest ecology
c. Desert ecology

22. Objectives of Ecology
• To study the interrelationship between organisms in
population;
• Location and distribution of organism;
• The structural variations and efficient modifications;
• Seasonal, annual and successional changes;
• Productive ecology;
• Mathematical models to relate communication;

23. Solar Energy
• The sun is thermonuclear reactor;
• Hydrogen is transformed to helium;
• Release of radiant energy in the form of electromagnetic
waves;
• This radiation contains high frequency, short-waves X-rays and
gamma rays;
• Low frequency, long-wave radio waves
• Speed of wave is 300,000 Km/sec

24. Population Analysis
The number of organism living in an isolated community
• Population Characteristics
• Input
 Individuals coming e.g. by birth
Immigration
• Output
Death
Emigration

25. Population Growth
• Population is related to environment and effect on it.
• World population was 1 billion in 1830,
• Population increase to 2 billion in 1930,
• 30 years for 3 billion (1960),
• 25 years for 4 billion (1985)
• 12 years for 5 billion (1997).
World population is growing by 92 million every year now

26. Distribution of Population

27. Population Density
• Population density is defined as the
number of persons per m2 or km2;
• Population density of Australia is 4
people per km2
• While Bangladesh is 1800 people per
km2.
• Iraq is 91 people per km2

29. Questions?