folio biology form 4

8/13/2019 Folio Biology Form 4

1/31


2/31

1

No. CONTENT PAGE

1. Introduction 2

2. Objective 3

3. Human Activities That Endanger An

Ecosystem

i. Causes

ii. Source

4 - 19

4. Greenhouse Effect And The Thinning Of

The Ozone Layer

20 - 25

5. Steps To Maintain A Stable

Environment

26 - 28

6. Conclusion 29

7. References 30


3/31

2

I , Muhammad Amin Bin Rosnan from 4 Alfa would like to thank those who

have been indirectly or directly involved in the making of this folio titled

ENDANGERED ECOSYSTEM. Ministry Of Educations effort in organizing the

making of this folio is highly appreciated in a way of increasing students

understanding in biology. Hence, not only increasing students level of understanding,but also increasing the value of studying biology as it is related to our living. By doing

this folio, it does not only increase my understanding towards biology, also it makes

me grow enthusiastic towards the intriguing subject, biology. I have now completed a

paperwork on the topic ENDANGERED ECOSYSTEM based on the last chapter

in the form 4 syllabus.

Nevertheless, I felt relief and grateful upon having such fabulous companion and

references who were my biology teacher Madam Airin Binti Abu Bakar, my parents,

helpful friends also siblings. I was really thankful to those who have helped me

out,being supportive yet helpful especially in providing extra information on the topic

which is given to in the making of this folio. Without their help surely I will not be

able to make this folio as a satisfying piece. Not to forget to my headmaster Tuan Haji

Sabuddin Bin Haji Sani for giving the students the opportunity to make this folio. Last

but not least, thank you once again to those who has helped directly or indirectly in the

making of the folio.


4/31

3

THE REASON FOR THE PAPERWORK IS BEING DONE IS DUE TO

SEVERAL OBJECTIVES AS STATED BELOW :

To evaluating human activities that endanger an ecosystem.

To understanding the greenhouse effect and the thinning of the ozone layer.

To realizing the importance of proper management of development

activities and the ecosystem.

To instill awareness among human about the importance of the preservation

and the conservation of the ecosystem.

To deduce the time for the depletion and the destruction of the environment

due to the environmental problems caused by human beings.


5/31

4

Human activities that threaten the ecosystem

The worlds population might reach to 10 billion in the next fiftyyears. Hence, when

there are increments in the number of the worlds population, it generally means that

there is an increasing demand for shelter, food, medicine, transport and raw materials.

Today, due to expectation of modern living and industrial revolution, the world has to

confront the destruction of forests tobuild more houses, to being use as plantation areas

and to buildroads just to fulfill humans needs.

Unplanned developments and mismanagement of ecosystem give rise to vast amounts

of environmental crisis. Among those environmental problems are greenhouse effect,

global warming,pollution, soil erosion, landslide, flashflood and ozone depletion.

The human activities that we are talking about are like agriculture, burning or

combustion, industrialisation and last but not least, deforestation.


6/31

5


7/31

6

Human activities made many drawbacks to the environment. Whether we like

them or not, these cons of the human activities have made all of us now leaving

in a hardship. The impacts can now be clearly seen by looking at our devastating

environment conditions.


8/31

7

Large areas of forests are cleared for extracting timber or fuel wood, agricultureneeds, and for the sake of urbanisation. The impacts are enormous and

outrageous. Let see what are the drawbacks of deforestation:

1.Deforestation causes soil erosion, landslides and flash floodsWithout proper development and planning, a land stripped of its vegetation is

subject to soil erosion.

Soil erosion is the removal and thinning oh the soil layer due to physical and

climatic processes, such as high rainfalls.

The absense of plant systems makes the soil structure unstable.

When there are heavy rains for a long period of time, the top layer of the soil

crumbles and this leads to landslides on steep hillsides.

The eroded soil is then carried by moving water and deposited at the bottom of

rivers.

This, together with depletion of water catchment areas, causes flash floods

during the rainy seasons.

Soil erosion caused the land to be depleted of minerals and natural resources,

making the land infertile.

Landslides Flash flood


9/31

8

2.Deforestation results in the loss of biodiversityDeforestation has a devastating effect on the biodiversity in tropical rainforests.

The destruction of millions hectares of forests by human activities means:

The removal of the bases of numerous food webs

The loss of habitats of many species of flora and fauna

The extinction of countless species and varieties of plants and animals. The

extinction of flora and fauna species reduces the biodiversity. Biodiversity can

be rich source of food and priceless medicines to mankind.

3.Deforestation causes climatic changes

Deforestation disrupts the normal weather patterns, creating hotter, drier weather

and causing global climatic changes.

The removal of trees reduces transpiration, rainfall and the rate at which plants

absorb carbon dioxide from the atmosphere during photosynthesis.

This leads to an increase in the carbon dioxide level in the atmosphere. High

levels of carbon dioxide prevent heat from escaping from the atmosphere.

This is known as the greenhouse effect which is believed to lead to global

warming.

Forest clearing and burning of wood result in air pollution and release more

carbon dioxide into the atmosphere .

Burning of trees in the tropics adds about 25% more carbon dioxide to the

atmosphere.


10/31

9

Excessive use of land for intensive farming decreases the space and resources

available for other species.

In intensive farming, farmers often use inorganic fertilisers, which contain

nitrates, phosphates and potassium ions, to improve crop yields.

Since nitrate and ammonium ions are highly soluble, the do not remain in the

soil for long and are quickly leached into the surrounding rivers and lakes.

This leads to eutrophication.

Intensive farming


11/31

10

The burning of fossil fuels adds about 75% of carbon dioxide tothe atmosphere.

An increase in carbon dioxide levels is associated with the greenhouse effect and

global warming.

Smoke from vehicle


12/31

11

An increase in human population generates an increase in both domestic and

industrial waste.

The dumping of waste in landfills poses a great danger to living organisms as toxic

subtances and other pollutants from the dumpsites leak into the ground and

eventually pollute the nearby water sources.

Factory


13/31

12

Pollution can be defined as any undesirable change in the environment due to the

release of harmful substances following undesirable human activities. There are four

types of pollution, namely:

Air Pollution

Air pollution is the change in the composition of air due to the presence of pollutants

(gases or particles) in high concentrations that can be harmful to life as well as to the

environment.

Air pollution from open burning

Air pollution

Water pollution

Thermal pollution

Noise pollution


14/31

13

Sources of Air Pollution

There are various sources of air pollution. These include:

Motor vehicles use fossil fuel which emits carbon dioxide, carbon monoxide, sulphur

dioxide, dust, etc. Industries also use fossil fuel as their source of energy. Open

burning produces a great amount of smoke, dust and carbon dioxide. This in turn can

cause hazes and affect visibility and human health.

Effects of Air Pollution on Human Health

Air pollution is detrimental to human health. The continuous inhaling of polluted air

can cause various ailments such as bronchitis, emphysema and cancer of the lungs

and silicosis. It also affects the eyes, causing them to become irritated and leading toconjunctivitis and other problems.

People wearing mask

Motor vehicles

Industries

Open burning


15/31

14

Effects of Air Pollution on Buildings

Air pollution also reacts with the structural components of buildings such as the brick

works, paint and the metal components.

Corrode building

Effects of Air Pollution on Plants

Air pollution also damages plants by oxidising the cellular components and enzymes

of the plants. The air pollution causes the leaves to turn yellow. This process is

known as chlorosis (a reduction in the amount of chlorophyll). Prolonged exposure to

air pollution causes the plants to weaken, be infected by diseases and eventually, the

plants die.

Dying tree


16/31

15

Effects of Air Pollution on the Climate

There are various effects of air pollution on the climate such as:

The Formation of Acid Rain

The formation of acid rain involves various stages. In the first stage, the large

amounts of sulphur dioxide and nitrogen dioxide released from factories and vehicles

combine with atmospheric water vapour/droplets. This combination produces

sulphuric acid and nitric acid in the water droplets. The presence of acid in the water

droplets causes the pH to drop below 5.0.

The formation of acid

rain

The greenhouse effect

Hazes


17/31


18/31

17

Eutrophication

One of the main effects of water pollution is eutrophication. Eutrophication is a

process where the water in ponds or lakes becomes rich in dissolved nutrients

(nitrates and phosphates) produced from fertilisers or sewage. The high concentration

of dissolved nutrients promotes the growth of algae and blue green bacteria which

cover up the surface of the ponds or rivers.

As a result, sunlight is prevented from reaching the algae and aquatic plants at the

bottom of the water. Photosynthesis cannot take place and they die. The

decomposition of dead plants by the aerobic bacteria uses more oxygen in the water

and reduces its concentration. This in turn increases the biochemical oxygen demand

(BOD).

The BOD is an indication of the amount of dissolved oxygen in water. A lower BOD

indicates that a high amount of oxygen has dissolved in the water while a higher

BOD indicates that a low amount of oxygen has dissolved in the water.

The BOD for clean water is less than 1 part per million (ppm; in highly polluted

water with human wastes, the BOD is between 200-400 ppm.

Algal bloom


19/31


20/31

19

Noise Pollution

Noise pollution is man-made noise that disrupts the environment. Excessive noise

pollution is harmful to living organisms. The sources of noise pollution are vehicles,

aeroplanes and trains, music, entertainment and drilling machines as well as noise

caused by piling at construction sites.

Excessive and very loud noise can damage the ear drums as well as the cells in the

inner part of the ear leading to hearing loss and deafness.

The threshold of the normal sound suitable for the ear is in the range of 40-60

decibels. Sounds of higher decibels, such as the sound of a jet engine (> 125 decibels)

and piling at construction sites (>100 decibels) are not suitable for the ears and

should be avoided.

Drilling


21/31

20

The Greenhouse Effect

The greenhouse effect is an effect in the atmosphere as a result of the presence of

certain gases , called the greenhouse gases.

Greenhouse gases in the atmosphere are similar to the glass panes of a greenhouse

which trap the heat and warm the greenhouse.

Carbon dioxide, cllorofluorocarbons (CFCs), methane, nitrous oxide, low level

ozone, and water vapour make up the greenhouse gases.

With the exception of CFCs, most of the greenhouse gases occur naturally.

However, all of them are also the results of human activities.

Today, data collected around the world show a steady increase in the concentration

of greenhouse gases. At the same time, there is also rapid development and

industrialisation.

Since the beginning of the Industrial Revolution, atmospheric concentrations of

carbon dioxide have increased by nearly 30%, the concentrations of methane have

more than doubled, and the concentrations nitrous oxide (N20) have risen by about

15%.


22/31

21

The greenhouse effect

Scientists believe that the combustion of fossil fuels and other human activities

such as deforestation and industrial production are the primary reasons for the

increased concentration of atmospheric carbon dioxide.

As the concentration of greenhouse gases rises, the greenhouse effect increases,

trapping more heat in the atmosphere and raising the average temperature on Earth.

This overall rise in the average temperature of the atmosphere is known as global

warming. The increase in atmospheric temperature has been high enough to cause

changes in the global climate.

Over last 40 years, the average temperature on Earth has increased by about

0.2-0.3C.

In Malaysia, temperature has been rising at 0.18C every decade.

Without emission control policies, it is projected that carbon dioxide

concentrations will be 30-150% higher than the present level. The average

temperature on earth may rise between 1.5C and 4.5C by 2100.


23/31

22


24/31

23

THE EFFECTS OF GLOBALWARMING

The Occurrence Of Floods

-As the mean temperature rises, the polarice caps and glaciers melt.

- A rise in sea levels caused low-lyingareas to be flooded.

Climatic Changes

- Global warming leads to changes inwind direction and the distribution of

rainfall. As a result, agrcultural activitiesare affected.

- Global warming causes weather patternsto change. This affects the distribution ofspecies which may lead to the extinction

of species in certain regions.

Occurence Of Drought

- Global warming increases thefrequency of droughts.

- The land becomes dry and infertile.This leads to a drop in crop yields.

Spread of Diseases

- With warmer climates, pests andvectors may spreads to new areas.

- The warmer conditions lead to anexpansion of territories for diseases-

carrying vectors, resulting in an increasein the outbreaks of diseases such as

malaria and dengue fever.


25/31

24

The Thinning Of The Ozone Layer

The ozone layer is a region in the stratosphere, between 20 and 25 kilometres

above the surface of the Earth.

The ozone layer contains high con centrations of ozone molecules (O3) that

absorb ultraviolet (UV) radiation and shield organisms from its damaging effects.

The ozone layer filters out UV radiation.


26/31

25

The thinning of ozone layer has been recorded by scientists since the 1970s.

In 1985, it was reported that the stratopheric ozone over the Antarctica has

declined by 40% since 1977.

The atmosphere in this area has very low ozone concentrations, resulting in the

formation of an ozone hole. An ozone hole has now appeared above the Arctics as

well.

Consequently, UV radiation has risen by 7% per decade in the southern

hemisphere.

This layer of ozone shields us from excessive ultraviolet radiation from the sun.

A satellite image of the ozone hole over the Antarctica. The dark region on

the image is actually an ozone hole.


27/31

26

There are many steps can be taken to maintain the balance of nature such

as:

1. Implementation of laws:

Environment Quality Act, 1974

Controls and prevents the pollution of the environment

Controls the type of licensing, content and quality of environment

Tests and examines the samples of substances and gas fromindustries

Natural Forestry Act, 1984

-Aims at protecting and preserving our forests and wildlife

Pesticides Act, 1974

-Aims at controlling the use of pesticides

Protection of Wildlife Act, 1972

-Aims at protecting wildlife animals, birds and plants

Fisheries Act, 1985

-Aims at controlling marine pollution


28/31

27

2.Use of technology:

Use modern equipment and chemicals to control oil spills.

Recycle rubbish.

To look for methods to do research.

Change organic rubbish to biogas.

Use less polluting and clean fuels in motor vehicles.

Control and treat the toxic and dangerous waste before disposing.

3.Education:

To increase the awareness and sensitivity of theindividual to the

environment.

To provide the basic knowledge of environmentalproblems and effects of

pollutions.

To teach the public the necessary skills to protect andmaintain a healthy

society.

To help the individuals to become responsible andsensitive to the

environment.


29/31

28

4.Preservation and conservation of the ecosystem:

Force the development companies to replant the forest trees after

deforestation.

Remaining the mangrove swamps area so that the ecosystemis protected.

Restore the mining and used land for agriculture.

Put effort in rivers cleaning to ensure there is sufficient supplyof water in

future) Practice of biological control.

A method of controlling the animal pests by using naturalpredators insteadof using chemical substances.

Factors to choose the animals predators.

5.Efficient use of energy: Reduce the burning of coal, petroleum and other fossil fuels.

Substitute natural gas for coal at power plants.

Improve fuel efficiency in vehicles-use cars that run on energy-efficient

engines.

Use a cleaner fuel by reducing the content of sulphur in diesel and

switching to gas.

Improve energy efficiency in factories.


30/31

29

The effects of unplanned development and mismanagement of the ecosystem

can lead to damaging consequences such as soil erosion, flash floods, landslides,

eutrophication ,pollution global warming, ozone depletion, climatic changes and

loss of biodiversity. There are four types of pollution which are air, water,

thermal, and noise pollution. Greenhouse gases released by various human

activities can trap heat in the atmosphere and raise the Earths average

temperature. Such an overall rise in the Earthstemperature can leads to global

warming. The thinning of ozone layer is mainly due to the accumulation of

chloroflurocarbon (CFCs)in the atmosphere. Sustainable development must take

into consideration of proper management of the ecosystem to ensure a balance

of nature is maintained.


31/31

Biology Form 4 Text Book.

Success (Oxford Fajar) Biology ( 2013 edition ) reference books.

folio biology form 4

Documents