UNIVERSITY OF CAGAYAN VALLEY
School of Liberal Arts and Teacher Education
College Avenue, Tuguegarao City 3500
Dr. Matias P. Perez Sr. Bldg.
Course Code : (BSIT-Auto 4A)
Course Title : Environmental Science
FINAL PERIODIC COVERAGE
MODULE No.
TITLE:
01
Population and Human Ecology
 Environmental Pollution
 Greenhouse Effect/ Global Warming
 Ozone Depletion
OVERVIEW
The aim of this module is to introduce students to recent developments
in natural resource management focused on the ideas of natural
capital, ecosystem services and sustainable landscape management
and thus a module set firmly with the socio-ecological tradition of
human ecology. The module will trace the traditions of this gradual
harmonization of resource management discourse and how it plays
out conceptually, empirically and at the interface of environmental
science, policy, and practice. The module will also set this tradition in a
critical frame, drawing back to underlying assumptions about the idea
of nature, and the relationship between nature, economy, human
development, and well-being. It will also have a practical edge by
covering issues of environmental citizenship and the ethical,
procedural, and practical rationales that underpin different forms and
levels of engagement in environmental decision making.
INTRODUCTION Any human activity brings along with it, many side effects. One aspect
of it could bring about development while the other side of the coin
could be a detrimental effect. These unfavorable changes often lead
to environmental issues that affect the natural balance of the
environment.
We can define environmental issues as the harmful effects of any
human activity on the environment. This includes both the biological
and physical aspects of the environment. Air pollution, water pollution,
natural environment pollution, garbage pollution, etc. are some of the
major environmental issues that are causing immense concern.
LEARNING
OUTCOMES
 discusses options for preventing and controlling pollution.
LEARNING
OBJECTIVES
 Describe the main types of pollution
 Describe the sources of pollution and the way pollutants reach
the environment
 Describe the main characteristics of water, air, and soil pollution
DISCUSSION
Pollution, also called environmental pollution, the addition of any
substance (solid, liquid, or gas) or any form of energy (such as heat,
sound, or radioactivity) to the environment at a rate faster than it can
be dispersed, diluted, decomposed, recycled, or stored in some
harmless form. The major kinds of pollution, usually classified by
environment, are air pollution, water pollution, and land pollution.
Modern society is also concerned about specific types of pollutants,
such as noise pollution, light pollution, and plastic pollution. Pollution of
all kinds can have negative effects on the environment and wildlife
and often impacts human health and well-being.
History of Pollution
Although environmental pollution can be caused by natural events
such as forest fires and active volcanoes, use of the word pollution
generally implies that the contaminants have an anthropogenic
source—that is, a source created by human activities. Pollution has
accompanied humankind ever since groups of people first
congregated and remained for a long time in any one place. Indeed,
ancient human settlements are frequently recognized by their
wastes—shell mounds and rubble heaps, for instance. Pollution was not
a serious problem if there was enough space available for each
individual or group. However, with the establishment of permanent
settlements by great numbers of people, pollution became a problem,
and it has remained one ever since.
Cities of ancient times were often noxious places, fouled by human
wastes and debris. Beginning about 1000 CE, the use of coal for fuel
caused considerable air pollution, and the conversion of coal to coke
for iron smelting beginning in the 17th century exacerbated the
problem. In Europe, from the Middle Ages well into the early modern
era, unsanitary urban conditions favored the outbreak of populationdecimating epidemics of disease, from plague to cholera and typhoid
fever. Through the 19th century, water and air pollution and the
accumulation of solid wastes were largely problems of congested
urban areas. But, with the rapid spread of industrialization and the
growth of the human population to unprecedented levels, pollution
became a universal problem.
Pollution Control
The presence of environmental pollution raises the issue of pollution
control. Great efforts are made to limit the release of harmful
substances into the environment through air pollution control,
wastewater treatment, solid-waste management, hazardous-waste
management, and recycling. Unfortunately, attempts at pollution
control are often surpassed by the scale of the problem, especially in
less-developed countries. Noxious levels of air pollution are common in
many large cities, where particulates and gases from transportation,
heating, and manufacturing accumulate and linger. The problem of
plastic pollution on land and in the oceans has only grown as the use
of single-use plastics has burgeoned worldwide. In addition,
greenhouse gas emissions, such as methane and carbon dioxide,
continue to drive global warming and pose a great threat to
biodiversity and public health.
Various Types of Pollution
There are various types of pollution which affect our lives on daily basis.
Environmental pollution is one the most significant challenges that the
world is facing in our day. Without a doubt, Environmental pollution has
existed for centuries. But it began to be a severe issue following the
industrial revolution in the 19th century. Pollution generally takes place
when pollutants pollute the natural surroundings, and it can bring
about changes that affect our everyday lifestyles unfavorably.
Pollution also results in environmental degradation. Evidence suggests
that since the industrial revolution, contaminants in atmosphere have
been growing day by day and resulting in severe damage to the
earth. Hazardous waste, toxic chemicals, suspended particles are
affecting both humans and animals on daily basis. Many of the toxins,
chemical and plastic have found their way in ecological food chain.
traces of such harmful substances are found in living organisms which
is a serious problem.
Pollutants are the main elements of pollution which are usually waste
materials of diverse types. Environmentalists consider that pollution can
disturb our ecosystem and the steadiness in the environment. With
modernization and urban growth, the rise of factories across the world,
the development in the field of technology, the increasing use of
vehicles and growth in our lives, pollution has hit the highest point.
Environmental pollution is a primary reason for giving rise to global
warming and many if the incurable human diseases. Pollution happens
in different forms such as air, water, soil, radioactive, light, noise, and
heat. There are different kinds of pollution and each of them have
their sources and causes associated with them.
Following are the Main Types of Pollution
The effects of pollution are undoubtedly many and extensive. Extreme
levels of pollution are causing scores of harm to human health, animal
health, tropical rain-forests etc. All kinds of pollution including air,
water, soil pollution, etc. have an impact on the environment.
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Air Pollution
Water Pollution
Land Pollution (soil pollution)
Noise Pollution
Radioactive/ Nuclear Pollution
Thermal Pollution,
Light pollution
Marine Pollution/ Ocean Pollution
Water Pollution
One of the most common forms of pollution is water pollution.
Generally, it is the contagion of any body of water including lakes,
groundwater, sea, oceans, etc. A few examples include raw sewage
and wastewater running into the lake or streams: Industrial waste drips
polluting groundwater, the illicit putting of stuff or items within bodies of
water, etc. The most explicit kind of water pollution affects surface
waters including oceans, lakes, and rivers which are used as drinking
water. Sewage, Nutrients, Chemical waste, radioactive waste, etc.
can make water polluted. Water pollution also results in death of water
bodies, kill organisms and fish, crabs, birds, seagull’s, dolphins, etc.
Common Sources of Water Pollution:
Human activities are the main source of water pollution. The most
polluting type include discharging of industrial waste into water bodies
such as lakes and rivers. The harmful chemicals and toxic waste
without being treated is directly discharged to water bodies. Another
reason is the mixing of untreated sewage to rivers. Polluted and
contaminated water from houses is not treated and rather made to
enter the water bodies. Plastic materials such as bottles, carry bags,
packaging material also find their way to water bodies which adds to
the water pollution and adversely affects its quality and aquatic life.
Another example of water pollution includes mixing up of high
temperature (hot water/ discharge) into water bodies at normal
temperature. The sudden change and rise in temperature of water
also has negative impact on aquatic life. Acid rain is also regarded as
one of the polluting factors.
Acid Rain: Sulphur dioxide and nitrogen oxides react with water in the
atmosphere producing sulphuric acid and nitric acid. These acids
come down along with the rain. This phenomenon is called acid rain.
The pH of acid rain varies from 3-6. The composition of acid rain is
sulphuric acid, nitric acid, and weak carbonic acid.
It has the following adverse effects:
 Causes respiratory and skin disorders.
 Affects productivity of plants by damaging the leaves.
 Enters the soil and affects pH and other conditions.
 Enters the ground and river which causes harm to the aquatic
life.
 Causes damage to marble and thus damages buildings and
monuments like the Taj Mahal
Air Pollution
Air Pollution is another main environmental pollution faced by our
world today. It takes place when damaging stuff including particulate
matter and biological molecules are dumped into Earth’s atmosphere.
It results in diseases, allergies, or premature death in humans. Air
pollution can bring harm to other living organisms such as animals and
food crops that we eat. In general, it is the pollution of air by smoke
and dangerous gases, chiefly oxides of carbon, sulfur, and nitrogen.
Exhausting fumes from vehicles, natural gas, the burning of fossil fuels,
Radiation spills or nuclear accidents, destructive off-gassing from things
such as paint, plastic production, and so on can cause pollution. Such
a type is generally regarded as “external pollution” only however it is
not true. Pollutants outside the home is as dangerous as inside the
home and offices. Such pollution which is present in a closed space of
home or office space is called indoor air pollution.
Effects of air pollution:
Formation of Photochemical Smog
When pollutants like hydrocarbons and nitrogen oxides combine in the
presence of sunlight, smog is formed. This is a mixture of gases and
since it is formed by photochemical reactions, it is called the
photochemical smog. The word ‘smog’ is derived from the two words-
smoke and fog. It forms a yellowish-brown haze especially during
winter and hampers visibility. It also causes many respiratory disorders
and allergies as it contains polluting gases.
Depletion of Ozone layer
The stratosphere of the atmosphere has ozone (O3). Ozone is known to
absorb the Ultraviolet (UV) rays present in the sun’s radiation. The UV
rays are believed to cause skin cancer and mutations. Thus, the ozone
protects us from the harmful effects of the UV rays. However,
hydrocarbons such as the chlorofluorocarbons (CFCs) destroy the
ozone molecules which deplete the ozone layer. Ozone holes have
been detected in the atmosphere which permit the UV rays to reach
the earth’s surface. The harmful effects of the UV rays are visible in the
countries such as Australia and New Zealand where the rate of skin
cancer is higher than the other regions of the world.
Aerosol Formation
Aerosol is formed by the dispersion of solid or liquid matter in the
atmosphere. There are natural aerosols also in the atmosphere.
However, polluting aerosols are formed by the pollutant particulate
matter like carbon particles. If the aerosols form a thick layer in the
troposphere, they affect the weather conditions by blocking the solar
radiation. Aerosols are also deposited on the leaves and affect the
photosynthesis. Aerosols disperse the organic metallic pollutants far
and wide.
Indoor Air Pollution
It refers to the physical, chemical, and biological characteristics of air
inside home, office, an institution, or center. Indoor air pollution is a
concern from the developed countries, where energy efficiency
improvements, sometimes make homes sterile, reducing ventilation
and increases pollutants level. Indoor air problem can be subtle and
do not always produce early impact on health.
Common Sources of air pollution:
The most widely known source of air pollution is the burning of fossil
fuels such as coal and petroleum. Fossil fuels are being used in large
quantities for over centuries in one or other form. Automobiles are
driven by fossil fuels which causes pollution. Another example is the
burning of coal in coal based electric power stations to generate
electricity. Burning of crops, waste and garbage are another equally
damaging to the environment. Construction activity though does not
result in release of harmful gases directly, but it adds large amount of
particulate matter and other harmful suspended particles which
causes pollution.
Soil Pollution
Soil Pollution takes place when the existence of toxic chemicals,
pollutants or impurities in the soil is in high. Soil contamination presents
a high risk to plants, wildlife, humans and indeed, the soil itself. The
surplus, escalating the use of chemicals such as pesticides, herbicides,
insecticides, and fertilizers is one of the main contributory factors.
The primary cause why the soil becomes impure is on account of the
presence of human-made waste. Industrial activity, agricultural
activities, waste disposal, accidental oil spills, acid rain, etc. are the
main reasons for soil pollution. Effects of soil pollution include the effect
on the health of humans, effect on the growth of plants, decreased
soil fertility, toxic dust, changes in soil structure, etc.
Massive cutting of trees, referred to as deforestation is a major
contributor of land pollution. The roots of trees which binds the soil gets
lost with time because of running water & also because of strong
winds. In hilly and mountain areas, trees play even a much more
important role and keeps big rocks in place. Because of activities such
as blasting, cutting of trees and construction in hilly areas, occurrences
of landslides have increased.
Common Sources of Soil Pollution
Soil pollution is a major problem with agricultural areas because of
extensive use of human-made waste products which are full of
chemicals. It directly affects the quality and quantity of crops. The
major contributory factors of soil pollution include use of chemical
fertilizers in agricultural practices. Some of the causes are same as that
of water pollution like acid rain, discharge of untreated sewage and
industrial waste. Additionally, throwing of garbage, especially plastic
material contributes substantially to this kind of pollution since they are
non-biodegradable. Burning of crops after harvesting also has
negative effect on the soil and it lowers its fertility.
Noise Pollution
Noise pollution has become more of an environmental issue since the
industrial age. It is disturbing or extreme noise that can harm the
activity or balance of human as well as animal life. The cause of most
outdoor noise globally is primarily originated from machines and
transportation systems, motor vehicles engines, factory machine
sounds, aircraft, and trains. Noise pollution can result from machines,
construction activities, and music performances. Noise pollution can
cause tinnitus, hearing loss, sleep disturbances, hypertension, highstress levels, and other destructive effects on humans. It causes
uneasiness and damage to live being’s mental and physical health.
Radioactive/ Nuclear Pollution
Radioactive pollution is a different type of pollution, it is caused
because of radioactive contamination (radio-logical contamination).
Such pollution is not very common in everyday life but of concern
where radioactive material and radioactive substances are used. The
risk of radioactive contamination increases in vicinity of Nuclear
thermal power plants, factories, in major hospitals etc. and can cause
serious problems if the radiation and exposure is not controlled.
Generally, the use of such harmful substance is very careful manner in
controlled environment. This is because of the widespread and longlasting damage in case of any leak or contact with such substance.
Dealing with radioactive waste becomes particularly important
because of the lack of safe disposal of such waste, thus mishandling of
radioactive waste can cause huge damage.
Some other Main types of pollution that we must be careful include:
Light pollution: It is a broad term that denotes many problems that are
caused by the useless, ugly, and pointless use of artificial light. Specific
class of light pollution consist of light trespass, over-illumination, glare,
light clutter, and sky glow.
Thermal pollution: It denotes the sudden increase or drops off in the
hotness of a natural body of water which may be ocean, lake, river,
sea, or pond by human influence. A general reason of thermal
pollution is the use of water as a coolant by power plants and business
firms.
Radioactive pollution: It can happen because of the release of
radioactive stuff or high-energy elements into the air, water, or soil on
account of excessive human activity, either by mistake or intentionally.
Ocean or marine pollution: This is caused because of the pollutants
and unwanted material entering water bodies. It can be result of such
material from various lower level water bodies or direct dumping into
oceans.
Greenhouse effect, global warming are well known issues cause
because of burning of fossil fuels such as coal, petroleum, natural gas
resulting in increased emission of carbon dioxide, nitrogen oxides,
Sulphur oxides, heavy metals in atmosphere. Out of various kinds of
pollution, air pollution is the major contributor to global warming.
People often talk about carbon dioxide (CO2) interchangeably with
GHGs. This is because CO2 is the most prevalent GHG. It represents
about three-quarters of all global GHG emissions, and the amount in
the atmosphere has risen dramatically. Before the industrial age, levels
were around 275 parts per million (ppm), now they are at 395 ppm,
with some areas at 400 or higher. This is significant since the last time
the planet had levels that high was likely 800,000 years ago. People
often talk about carbon dioxide (CO2) interchangeably with GHG.
When we cut down forests, we lose part of the system that reduces
GHGs. Additionally, if these cut trees are then burned or allowed to
decay, the carbon which was trapped in the tree is then released
back into the atmosphere. So not only do we lose an ally for reducing
GHGs, we end up causing an additional increase.
Global Warming: Most of the solar radiation entering the earth’s
atmosphere is reflected into the space. However, some of the heat is
absorbed by the gases like the carbon dioxide. This serves to keep the
earth warm much like the greenhouses. Greenhouses are glasshouses
which maintain a temperature higher than the surroundings for the
plants to grow and yield better. The other gases that contribute to this
are water vapor, methane, chlorofluorocarbons (CFCs) and nitrous
oxide. These gases are called the greenhouse gases.
While greenhouse effect is a necessary and natural phenomenon.
Every year the temperature is going up due to pollution and the levels
of these greenhouse gases is also going up. This is called global
warming. According to estimates, at the current rate of increase, the
average global temperature will go up by 3oC to 8oC in the next 100
years.
This has an adverse effect on climate of different regions. Moreover,
distribution of plants and animals is also disturbed. Food and
agricultural production will be hit drastically. Melting of snow caps and
resultant increase in sea levels
Various rules and regulations have been formed all over the world.
Environmental Protection Agency, Water Department, Pollution
Boards, NGOs, and departments have been formed. These agencies
or departments forms guidelines, policies, and acts to check the
pollution levels. They also work on collecting data about worst polluted
places, hazardous waste sites, changes in pollution levels etc. Rules &
regulations in form of acts defines the acceptable level of pollution,
defines penalties, actions, and other requirements to be kept in mind.
Depending on the need, such rules are applicable to individuals,
business entities, industries, manufacturers and as well as government
undertakings.
ACTIVITY
Activity # 1
1. Why is a point source of pollution easier to identify than a non-point
source of pollution?
2. Describe what is meant by the term’s liquid waste and solid waste,
using examples from your own experience to illustrate your answer.
3. Describe how water pollution can change the characteristics of
water.
Prepared by: Dr. Soledad R. Taguibao