SEKOLAH MENENGAH KEBANGSAAN KHIR JOHARI

BIOLOGY

NAME : NURUL IZZATIE BINTI MOHAMAD

CLASS : 4 SCIENCE 3TEACHER : PN NOORNUJAIMI BT

NORDIN

CONTENTS PAGE

?? Objectives 2?? Problem Statement 3?? Air Pollution

The Sources The Pollutants The Effects Formation of Acid Rain

4-8

?? Water Pollution The Sources The Pollutants The Effects Eutrophication Biochemical Oxygen Demand

(BOD)

9-14

?? Reference 15

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?? To identify human activities that cause air and water pollution

?? To explain the effects of air and water pollution on living things and environment

?? To state the sources of the pollutants of air and water pollution

?? To describe the process of eutrophication and the formation of acid rain

?? To explain the effects of eutrophication and acid rain

?? What are the human activities that cause air and water pollution?

?? What are effects of air and water pollution on living things and environment?

?? What are the sources of the pollutants of air and water pollution?

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?? What are the process of eutrophication and the formation of acid rain?

?? What are the effects of eutrophication and acid rain?

Air pollution takes places when gases or particles accumulate in the air in high concentrations that can harm living organisms

and the environment.

SOURCES OF AIR POLLUTION

Sources of Air Pollution Due To Human Activities Are:

MOTOR VEHICLES

a.Motor vehicles such as cars, motorcycles, lorries, aeroplanes, ships and trains

b.Fossil fuels that include petroleum, diesel and gas used in motor vehicles produce carbon dioxide, carbon monoxide, sulphur dioxide, nitrogen dioxide, lead, soot and dust.

INDUSTRY

a. In the industrial sector, electric power stations and factories (cement, wood, chemical, iron) use diesel and discharge many types of pollutants into the atmosphere

b. Among the pollutants produced are carbon monoxide, sulphur dioxide, nitrogen dioxide, chlorine, dust and smoke.

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c. Agricultural chemicals such as airborne, pesticides, insecticides and herbicides are also sprayed into the air instead of landing on planted crops.

OPEN AIR BURNING

a. The burning of rubbish, solid wastes and forests produces a lot of smoke (causing haze), carbon dioxide and dust.

b. There are many people who practise open burning either of domestic rubbish or at rubbish dumps.

Figure 1 Sources of Air Pollutants

THE AIR POLLUTANTS

1. Sulphur dioxide2. Nitrogen dioxide3. Small particles, dust, smoke or soot4. Hydrocarbons (volatile organic compounds)5. Carbon monoxide6. Ozone7. Heavy metals (lead, mercury, cadmium and others)

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EFFECTS OF AIR POLLUTION

Effects of Air Pollution on the Health of Humans:

BRONCHITIS

a. Acute inflammation of the air passages within the lungsb. The patients suffers from high fevers, chest pains,

breathing difficulties and incessant coughing

EMPHYSEMA

a. Alveolar walls collapse and air sacs join with each other, thereby reducing the total surface area to volume ratio. Hence the total effective respiratory surface of the lugs for gaseous exchanged is reduced.

b. The symptoms are breathing difficulties and coughing and feeling tired.

SILICOSIS AND DARK LUNGS

a. Silicosis is caused by the breathing in of silicon dioxide (silica) and also of carbon particles.

b. The dust in the lungs stimulates the growth of scar tissue or fibroid around the dust particles.

c. The continuous growth of scar tissue will reduce the efficient functioning of the lungs

Effects of Air Pollution on Buildings:

Pollutants Material acted on DamageCarbon dioxide

Bricks made from limestone

Weakens the structure

Oxides of sulphur

Iron, copper, aluminium, skin, materials of the building structure (bricks, limestone, marble)

Corrodes to rust, copper sulphate, and aluminium sulphate. Chemical reactions weaken the whole building structure and denatures proteins and enzymes

Hydrogen sulphide

Metal silver and copper, paintworks

Turn metallic surface dull, lead based paints turn black because of the formation of lead

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oxideOzone Rubber, textiles and

colourCracks appear, becomes soft and easily torn colour turns dull

Nitrogen dioxide

Colour Colour turns dull

Dusts Building Dust covered and dirty

FORMATION OF ACID RAIN

Figure 2 Formation of Acid Rain

1. Sulphur dioxide and nitrogen dioxide released subsequently dissolve in atmospheric water vapour before coming down as acid rain in the form of sulphurous acid, sulphuric acid, nitrous acid and acid nitric.

2. Acid rain absorbed by the soil dissolves many mineral salts and washes them into rivers and lakes. This releases poisonous chemicals.

3. Acid rain flowing into rivers and lakes upsets the ecosystem by destroying many species of living organisms such as phytoplankton, zooplankton, fishes and other aquatic animals.

4. Acid rain falling on plants changes the colour of the leaves from green to purple and cause the leaves to die.

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Figure 3 Effects of Acid Rain on Human Health, Plants and Aquatic Animals

Figure 4 Effects of Acid Rain on Statue

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Water as a universal solvent because many types of chemical substances can dissolve in it makes it easy to be polluted.

Water pollution is caused by domestic wastes, industrial wastes that are discharged directly into rivers. Soil erosion can also

lead to water pollution.

THE SOURCES OF WATER POLLUTANTS AND THEIR EFFECTS

Figure 5 The Causes of Water Pollution

Source of Air

Pollution

Pollutants Harmful Effects

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Discharge of domestic wastes into rivers

Untreated sewage (faeces and liquid wastes)

Encourages growth of bacteria, causing diseases such as cholera, typhoid and dysenteryBacteria increases due to increased concentration of nitrates and phosphates in untreated sewageBacteria use up the oxygen supply in water to decompose the untreated sewage and other organic wastes. This reduces the oxygen concentration and kills the aquatic animals and plants. The decomposition of dead organisms further increases the bacteria population in the waterCause bad odour and unsightly view

RubbishDetergents

Non-biodegradable rubbish prevents sunlight from reaching the plants in the river and prevents oxygen diffusion. This threatens aquatic lifeHigh concentration of detergents reduces the concentration of oxygen in the water and threatens the lives of aquatic organisms

Oil spillage Oil that spills from ships’ oil tanks

Causes death to all life forms in the seaCauses death of sea birds and sea lionsPollutes the beaches

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Figure 6 Discharge of Industrial Wastes

Source of Air

Pollution

Pollutants Harmful Effects

Discharge of industrial wastes into rivers

Organic wastes from remains of oil palms and rubber plantationsToxic chemical wastes from electronic factories such as arsenic, lead, mercury and zinc

Contaminate the water physicallyDecomposition of organic wastes reduces the concentration of oxygen in waterAccumulation of toxic chemicals that are non-biodegradable through the food chain in aquatic organisms results in the poisoning of aquatic animals and man. These toxic substances damage body organs and are harmful to man, causing cancer and mutation.

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Source of Air

Pollution

Pollutants Harmful Effects

Discharge of agricultural wastes (leaching from farms to nearby rivers)

Fertilisers and faeces which contain nitrates and phosphates

The high concentration of nitrates and phosphates in rivers or ponds

results in eutrophication. The nitrates and phosphates promote

rapid growth of algae, the algae will later use up the oxygen supply in the water, killing fish and other

aquatic organisms.Agrochemicals such as insecticides, pesticides, herbicides and fungicides

Agrochemicals are non-biodegradable, highly toxic and

harmful as they can be passed on in food chains and accumulate in the bodies of aquatic animals and man. These chemical wastes in significant amounts are poisonous to aquatic

animals and can damage the organs in the body, cause cancer and contaminate water supplies.

EUTROPHICATION

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1. Eutrophication occurs when inorganic nutrients and organic material enter a river or a lake. The discharge of untreated sewage into a river also has an immediate effect on the biotic and abiotic components of the water ecosystem.

2. The enrichment of lakes and rivers with nutrients encourages photosynthesising organism in the water, particularly algae, to grow rapidly, resulting in a population explosion known as an algal bloom.

3. The density of the algae so high that light intensity in the water to reach the lower depths is greatly reduced. As a result, the plants in the water die.

4. The death of plants and algae and the subsequent decomposition of these organisms by bacteria lead to a severe depletion of oxygen in the water for the decomposition increases the usage of oxygen, causing the death of aerobic organisms.

5. The rapid growth of the algae and the process of decomposition lead to the increase in biochemical oxygen demand (BOD).

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Figure 7 Eutrophication of a River

BIOCHEMICAL OXYGEN DEMAND (BOD)

1. BOD refers to the amount of dissolved oxygen taken up by microorganisms that decompose organic waste matter in water.

2. The dissolved oxygen concentration can be used as an indicator of water pollution level.

3. A high BOD indicates the presence of a large number of microorganisms which suggest a high level pollution. The higher the BOD value, the more polluted the water sample is.

4. Methylene blue solution is used to analyse the presence of oxygen in water. In the presence of low concentration of oxygen, the colour of methylene blue is decolourised rapidly. Hence, the BOD value of the water is high.

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Betsy Teh Lay Hong, 2012. Longman Essential Biology SPM Selangor: Pearson Malaysia Sdn. Bhd.

Mah Chee Wai, Tina Lim Swee Kim, 2013. Nexus Bestari Biology SPM. Selangor: Sasbadi Sdn.Bhd.http://www.google.com.my/search?newwindow=1&hl=en&biw=1366&bih=643&site=imghp&tbm=isch&sa=1&q=eutrophication+diagram&oq=eutroph&gs_l=img.1.2.0l10.73001.78539.0.81134.10.7.2.1.1.0.205.1031.0j6j1.7.0....0.0..1c.1.20.img.DPVTEJV2nmU#facrc=_&imgdii=_&imgrc=i5lNXqppgkPv7M%3A%3BtZVMDotjolTRrM%3Bhttp%253A%252F%252Fthebritishgeographer.weebly.com%252Fuploads%252F1%252F1%252F8%252F1%252F11812015%252F9983563_orig.jpg%3Bhttp%253A%252F%252Fthebritishgeographer.weebly.com%252Ffreshwater-environments-and-management.html%3B655%3B461

http://www.google.com.my/search?newwindow=1&hl=en&site=imghp&tbm=isch&source=hp&biw=1366&bih=643&q=source+of+water+pollution&oq=source+of+wat&gs_l=img.1.1.0l10.90908.101254.0.104156.17.12.2.3.4.0.263.2586.0j3j9.12.0....0.0..1ac.1.20.img.JddPh3XK-fY#facrc=_&imgdii=_&imgrc=jo2gSNVJkKRqKM%3A%3B1cIFk5iMsPn5JM%3Bhttp%253A%252F%252Fcnx.org%252Fcontent%252Fm41441%252F1.7%252Fgraphics7.png%3Bhttp%253A%252F%252Fcnx.org%252Fcontent%252Fm41441%252F1.7%252F%3B646%3B399

http://www.google.com.my/search?newwindow=1&hl=en&biw=1366&bih=643&site=imghp&tbm=isch&sa=1&q=effects+of+water+pollution+diagram&oq=effects+of+water+pollution+diagram&gs_l=img.3...6512.12103.0.12474.13.12.0.1.1.0.390.2307.2j5j4j1.12.0....0.0..1c.1.20.img.HahB1ex-b3w

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