Chapter 9 : Endangered Ecosystem

9.2 The Greenhouse Effect and the Thinning of the Ozone Layer.

9.3 The Importance of Proper Management of Development Activities and the Ecosystem.

9.2 The Greenhouse Effects and the Thinning of the Ozone Layer

The Greenhouse EffectWhat is a green house effect?o The greenhouse effect is a process by which

radiactive energy leaving a planetary surface is absorbed by some atmospheric gases, called greenhouse gases. The greenhouse gases are carbon dioxide, carbon monoxide, oxides of nitrogen, methane and chlorofluorocarbons (CFCs). They transfers energy to other components of the atmosphere, and it is re-radiated in all directions, including back down towards the surface. This transfers energy to the surface and lower atmosphere, so the temperature is higher than it would be if direct heating by solar radiation were the only warming merchanism.

o The greenhouse effect influences living things and the ecosystem in the following ways. The amount of carbon dioxide in atmosphere

increases, the temperature of the earth rises and this increases the rate of photosynthesis and the crop yield.

The greenhouse effect causes global warming because the rise in the temperature of the earth accelerates evaporation of water and reduces soil humidity.

Climatic changes such as changes in the direction of the wind and the distribution of rainfall will bring about storms, drought or floods.

Melting of ice at the North Pole and South Pole will increase the sea level and cause floods in

low-lying areas.

oThe following measures can be taken to reduce the greenhouse effect.

Use alternative forms of energy such as wind/hydro/solar/geothermal energy. Reduce the burning of fossil fuels. Reduce deforestation. Replant trees which have been cut down. Reduce the number of glass buildings.

The Thinning of the Ozone Layer

o Ozone gas (O3) occurs naturally in the stratosphere layer (ozone layer) which is 17-25 km above the Earth’s surface.

o Examples of substances/gases what will react with the ozone molecules to form molecular oxygen are chlorofluorocarbons, carbon dioxide, oxides of nitrogen and methane gas.

o The main cause of ozone depletion is the increase in the level of chlorofluorocarbons (CFCs), which are active chemicals that contain chlorine, carbon and fluorine.

o The impact of ozone depletion on humans include the risk of skin cancers, cataracts and sunburns.

o UV radiation weakens the immune system and the ability of the body to resists infectious diseases.

The temperature of the surroundings rises, and there are changes in the direction of the

wind, the global climate and the sea level.Antarctica was an early victim of ozone

destruction. A massive hole in the ozone layer right above Antarctica now threatens not only that continent, but many others that could be

the victims of Antarctica’s melting icecaps.

9.3 Importance of Proper Management of Development Activities and The Ecosystem.

Implementation of LawsThe Malaysian government has implemented acts

and laws to protect the quality of the environment. Examples: The Environmental Quality Act, 1974,

1985 (amendment) and National Forestry Act, 1984.

Regulation for disposal of crude palm oil waste in water (Crude Palm Oil Regulations, 1977) Regulation for industrial and domestic waste

disposal (Sewage and Industrial Effluents Regulations, 1979)

Use of Technology Use Biotechnology, special bacteria can be

produced to break down the oil layer from an oil spill in the sea.

Exhaust gases are passed through catalytic converters to reduce the amount of carbon monoxide and oxides of nitrogen emitted from the exhaust pipes.

Filters are fixed on chimneys to reduce the release of toxic gases.

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Unleaded petrol, natural gas and alcohol can be used to replace leaded petrol for vehicles.

Treat sewage in sewage treatment plants and treat toxic waste from factories before it is discharged so as to reduce water pollution.

Organic waste from agriculture can be processed into methane for fuel.

ARASSOYO?(understood

?)

Education on the Management of Resources The public must be educated on the importance

of protecting and caring for the environment through the mass media and various environment campaigns.

The public must be educated on the concept of the 4Rs. The 4Rs stand for recycle, reuse, reduce, renew.

a) Recycle – collecting and segregating waste materials according to their types and turning this waste materials into new products.

b) Reuse things such as old plastics , containers, and bottles instead of throwing them away.

c) Reduce the use of materials.d)Renew the use of materials such as bottles and

plastic containers after they are clean.

Preservation and Conservation of The Soil, Water, Flora and Fauna of Forests and Mangrove Swamps. Conservation and preservation of land will

decrease leaching and soil erosion. Practice crop rotation, planting, of cover

crops, controlled grazing, contour ploughing, terracing, use of synthetic and natural fertilizers to fertilize the soil and practice strip cultivation.

Water sources must be preserved and not use as dumping sites for domestic and toxic waste which can pollute the water.

Natural habitats will perish, animals and plants will be endangered when there is no control on human activities such as deforestation for development, agriculture and industry.

Replanting programmes ensure that the trees which have been cut down by logging activities are replaced with new trees so that the forest will continue to productive and we able to support lives.

Minimise damage to the environment when building an infrastructure.

Laws should be implemented to punish the people involved in illegal logging activities.

Clearing of mangrove swamps for timber and agriculture robs the flora and fauna of their habitats. Effort must be made to conserve these mangrove swamps to maintain ecological balance.

The Practice of Biological Control.

Biological control is an alternative method of controlling pests. It involves the used of natural predators to reduce the population of pests.

It is effective and will not pollute the environment.

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