WAEC SSCE - Geography - 2015 (Essay)
Tambaya 1 Rahoto
(a) Define the following terms: (i) death rate: (ii) population explosion
(b) Explain the factors that influence death rate in Tropical Africa.
(c) Outline three effects of a growing, population in Tropical Africa.
(a) Definitions
- (i) Death rate: the number of deaths per 1,000 people in a population in one year. It is also called the crude death rate or mortality rate.
- (ii) Population explosion: a very rapid and sudden increase in the population of an area over a short period, caused mainly by a high birth rate combined with a sharply falling death rate.
(b) Factors that influence death rate in Tropical Africa
- Medical/health facilities: where hospitals, drugs, immunisation and trained personnel are adequate the death rate falls; where they are scarce it rises.
- Food supply and nutrition: adequate, balanced food lowers deaths, while famine and malnutrition raise them.
- Disease: the prevalence of malaria, cholera, HIV/AIDS and other tropical diseases raises mortality.
- Sanitation and clean water: good sanitation and safe water reduce deaths, poor sanitation increases them.
- War, natural disasters and civil unrest, and the general standard of living/poverty, also affect death rates.
(c) Three effects of a growing population in Tropical Africa
- Pressure on land and food: more mouths to feed lead to food shortage, land fragmentation and over-cultivation.
- Strain on social services and infrastructure: schools, hospitals, housing, water and roads become overstretched.
- Unemployment and overcrowding: too many job-seekers cause high unemployment, rural-urban migration, slums and environmental degradation.
Bayanin Amsa
(a) Definitions
- (i) Death rate: the number of deaths per 1,000 people in a population in one year. It is also called the crude death rate or mortality rate.
- (ii) Population explosion: a very rapid and sudden increase in the population of an area over a short period, caused mainly by a high birth rate combined with a sharply falling death rate.
(b) Factors that influence death rate in Tropical Africa
- Medical/health facilities: where hospitals, drugs, immunisation and trained personnel are adequate the death rate falls; where they are scarce it rises.
- Food supply and nutrition: adequate, balanced food lowers deaths, while famine and malnutrition raise them.
- Disease: the prevalence of malaria, cholera, HIV/AIDS and other tropical diseases raises mortality.
- Sanitation and clean water: good sanitation and safe water reduce deaths, poor sanitation increases them.
- War, natural disasters and civil unrest, and the general standard of living/poverty, also affect death rates.
(c) Three effects of a growing population in Tropical Africa
- Pressure on land and food: more mouths to feed lead to food shortage, land fragmentation and over-cultivation.
- Strain on social services and infrastructure: schools, hospitals, housing, water and roads become overstretched.
- Unemployment and overcrowding: too many job-seekers cause high unemployment, rural-urban migration, slums and environmental degradation.
Tambaya 2 Rahoto
(a) List any three types of mountains.
(b) In what four ways are mountains important to man?
(c) Outline two problems caused by mountains.
(a) Three types of mountains
- Fold mountains (e.g. the Alps, Himalayas, Atlas).
- Block (fault) mountains or horsts (e.g. the Ruwenzori).
- Volcanic mountains (e.g. Mount Cameroon, Kilimanjaro).
(Others include residual mountains formed by denudation, e.g. inselbergs.)
(b) Four ways mountains are important to man
- Source of rivers: High mountains induce heavy rainfall and act as water catchment areas, feeding rivers used for water supply, irrigation and hydro-electric power.
- Climatic barrier and rainfall: They force moist air to rise and cool, giving relief (orographic) rainfall on the windward side that supports farming.
- Mineral and forest resources: Mountains contain valuable minerals and timber, and their slopes support forestry and grazing.
- Tourism, defence and settlement: Their scenery attracts tourists, they served historically as natural defensive barriers, and cool highland climates favour settlement and plantation crops such as tea and coffee.
(c) Two problems caused by mountains
- They hinder transport and communication, making the construction of roads and railways difficult and expensive.
- They create a rain-shadow effect, leaving leeward areas dry, and their steep slopes encourage soil erosion and landslides while limiting the amount of land available for farming and settlement.
Bayanin Amsa
(a) Three types of mountains
- Fold mountains (e.g. the Alps, Himalayas, Atlas).
- Block (fault) mountains or horsts (e.g. the Ruwenzori).
- Volcanic mountains (e.g. Mount Cameroon, Kilimanjaro).
(Others include residual mountains formed by denudation, e.g. inselbergs.)
(b) Four ways mountains are important to man
- Source of rivers: High mountains induce heavy rainfall and act as water catchment areas, feeding rivers used for water supply, irrigation and hydro-electric power.
- Climatic barrier and rainfall: They force moist air to rise and cool, giving relief (orographic) rainfall on the windward side that supports farming.
- Mineral and forest resources: Mountains contain valuable minerals and timber, and their slopes support forestry and grazing.
- Tourism, defence and settlement: Their scenery attracts tourists, they served historically as natural defensive barriers, and cool highland climates favour settlement and plantation crops such as tea and coffee.
(c) Two problems caused by mountains
- They hinder transport and communication, making the construction of roads and railways difficult and expensive.
- They create a rain-shadow effect, leaving leeward areas dry, and their steep slopes encourage soil erosion and landslides while limiting the amount of land available for farming and settlement.
Tambaya 3 Rahoto
a) Draw a sketch map of Nigeria. On the map. show and name one area with:
(i) Mangrove swamp vegetation: (ii) Rain forest vegetation: (iii) Guinea savanna vegetation: (iv) Sudan savanna vegetation.
(b) Name three types of trees found in the forest zone of Nigeria.
(c) Explain four contributions of forest vegetation to the economic development of Nigeria.
(a) Sketch map of Nigeria showing vegetation areas
The vegetation changes mainly from wetter conditions in the south to drier conditions in the north. Therefore, mangrove swamp occurs around the Niger Delta coast; rain forest occurs inland in southern Nigeria; Guinea savanna occurs in the Middle Belt; and Sudan savanna occurs in the far north.
(b) Three trees found in the forest zone of Nigeria
- Mahogany
- Iroko
- Obeche
Other acceptable examples include African walnut, opepe, sapele and silk cotton.
(c) Four contributions of forest vegetation to Nigeria’s economic development
- Supply of industrial raw materials: forests provide timber for sawmills, furniture and plywood industries, as well as materials such as latex for rubber production.
- Employment: forestry provides work for lumbermen, hunters, sawmill workers, carpenters, transporters and people involved in forest-product trade.
- Construction and export earnings: wood is used for building houses and making furniture. Timber can also be exported, earning foreign exchange for Nigeria.
- Food, medicine and tourism: forests provide fruits, nuts, herbs and medicinal plants. They also support wildlife and attractive natural areas, which can promote tourism.
Examination reminder: For economic contributions, state both the forest product or service and how it helps the economy, such as providing jobs, supplying an industry, supporting construction or earning foreign exchange.
Bayanin Amsa
(a) Sketch map of Nigeria showing vegetation areas
The vegetation changes mainly from wetter conditions in the south to drier conditions in the north. Therefore, mangrove swamp occurs around the Niger Delta coast; rain forest occurs inland in southern Nigeria; Guinea savanna occurs in the Middle Belt; and Sudan savanna occurs in the far north.
(b) Three trees found in the forest zone of Nigeria
- Mahogany
- Iroko
- Obeche
Other acceptable examples include African walnut, opepe, sapele and silk cotton.
(c) Four contributions of forest vegetation to Nigeria’s economic development
- Supply of industrial raw materials: forests provide timber for sawmills, furniture and plywood industries, as well as materials such as latex for rubber production.
- Employment: forestry provides work for lumbermen, hunters, sawmill workers, carpenters, transporters and people involved in forest-product trade.
- Construction and export earnings: wood is used for building houses and making furniture. Timber can also be exported, earning foreign exchange for Nigeria.
- Food, medicine and tourism: forests provide fruits, nuts, herbs and medicinal plants. They also support wildlife and attractive natural areas, which can promote tourism.
Examination reminder: For economic contributions, state both the forest product or service and how it helps the economy, such as providing jobs, supplying an industry, supporting construction or earning foreign exchange.
Tambaya 4 Rahoto
(a) Explain the following terms:
1.rotation of the earth;
2.revolution of the earth;
3.equinox.
(b) Outline three effects of the revolution of the earth
(a) Explanation of terms
- Rotation of the earth: This is the spinning of the earth on its own axis from west to east. The axis is an imaginary line drawn through the North and South Poles, inclined at \(66\tfrac{1}{2}^\circ\) to the plane of the earth's orbit (or \(23\tfrac{1}{2}^\circ\) from the vertical). One complete rotation takes about 24 hours and gives rise to day and night.
- Revolution of the earth: This is the movement of the earth in its orbit around the sun. The earth completes one revolution in about \(365\tfrac{1}{4}\) days (one year), moving in an elliptical path while its axis remains tilted and pointing in the same direction (parallelism of the axis).
- Equinox: This is the time, occurring twice a year (around 21 March and 23 September), when the sun is overhead at the equator and day and night are of equal length (12 hours each) all over the world. The word means "equal night".
(b) Three effects of the revolution of the earth
- It causes the seasons of the year (spring, summer, autumn and winter) because of the changing position of the earth relative to the sun combined with the tilt of the axis.
- It causes varying lengths of day and night at different times of the year, especially away from the equator.
- It causes the apparent migration of the overhead sun between the Tropic of Cancer and the Tropic of Capricorn, and forms the basis of the calendar year of about \(365\tfrac{1}{4}\) days, which necessitates a leap year.
Bayanin Amsa
(a) Explanation of terms
- Rotation of the earth: This is the spinning of the earth on its own axis from west to east. The axis is an imaginary line drawn through the North and South Poles, inclined at \(66\tfrac{1}{2}^\circ\) to the plane of the earth's orbit (or \(23\tfrac{1}{2}^\circ\) from the vertical). One complete rotation takes about 24 hours and gives rise to day and night.
- Revolution of the earth: This is the movement of the earth in its orbit around the sun. The earth completes one revolution in about \(365\tfrac{1}{4}\) days (one year), moving in an elliptical path while its axis remains tilted and pointing in the same direction (parallelism of the axis).
- Equinox: This is the time, occurring twice a year (around 21 March and 23 September), when the sun is overhead at the equator and day and night are of equal length (12 hours each) all over the world. The word means "equal night".
(b) Three effects of the revolution of the earth
- It causes the seasons of the year (spring, summer, autumn and winter) because of the changing position of the earth relative to the sun combined with the tilt of the axis.
- It causes varying lengths of day and night at different times of the year, especially away from the equator.
- It causes the apparent migration of the overhead sun between the Tropic of Cancer and the Tropic of Capricorn, and forms the basis of the calendar year of about \(365\tfrac{1}{4}\) days, which necessitates a leap year.
Tambaya 5 Rahoto
(a) Define climate.
(b) Describe the three climatic belts recognized by the Greek system of climatic classification.
(c) Outline three reasons why Koppen’s system of climatic classification is the most widely accepted.
(a) Definition of climate
Climate is the average weather conditions of a place recorded and generalised over a long period of time, usually not less than 35 years. It considers elements such as temperature, rainfall, pressure, humidity and wind.
(b) The three climatic belts of the Greek system
The ancient Greeks divided the earth into three temperature zones based on distance from the equator and the angle of the sun's rays:
- The Torrid (Tropical) Zone: Lying between the Tropic of Cancer (\(23\tfrac{1}{2}^\circ\)N) and the Tropic of Capricorn (\(23\tfrac{1}{2}^\circ\)S). The sun is overhead at some time of the year, so it is permanently hot.
- The Temperate Zones: Two belts lying between the tropics and the Arctic Circle (\(66\tfrac{1}{2}^\circ\)N) and Antarctic Circle (\(66\tfrac{1}{2}^\circ\)S). They receive slanting rays and experience moderate, seasonal temperatures.
- The Frigid (Polar) Zones: Two belts lying between the polar circles and the poles. The sun's rays are very oblique, so they are permanently cold.
(c) Three reasons why Koppen's system is the most widely accepted
- It is based on measurable, quantitative data (definite values of temperature and rainfall), so it is precise and can be applied objectively anywhere.
- It links climate closely with natural vegetation, making the classification meaningful and easy to relate to the real world.
- It uses a simple system of letter symbols (A, B, C, D, E, etc.) that is concise, easy to remember and allows detailed sub-division of climatic types.
Bayanin Amsa
(a) Definition of climate
Climate is the average weather conditions of a place recorded and generalised over a long period of time, usually not less than 35 years. It considers elements such as temperature, rainfall, pressure, humidity and wind.
(b) The three climatic belts of the Greek system
The ancient Greeks divided the earth into three temperature zones based on distance from the equator and the angle of the sun's rays:
- The Torrid (Tropical) Zone: Lying between the Tropic of Cancer (\(23\tfrac{1}{2}^\circ\)N) and the Tropic of Capricorn (\(23\tfrac{1}{2}^\circ\)S). The sun is overhead at some time of the year, so it is permanently hot.
- The Temperate Zones: Two belts lying between the tropics and the Arctic Circle (\(66\tfrac{1}{2}^\circ\)N) and Antarctic Circle (\(66\tfrac{1}{2}^\circ\)S). They receive slanting rays and experience moderate, seasonal temperatures.
- The Frigid (Polar) Zones: Two belts lying between the polar circles and the poles. The sun's rays are very oblique, so they are permanently cold.
(c) Three reasons why Koppen's system is the most widely accepted
- It is based on measurable, quantitative data (definite values of temperature and rainfall), so it is precise and can be applied objectively anywhere.
- It links climate closely with natural vegetation, making the classification meaningful and easy to relate to the real world.
- It uses a simple system of letter symbols (A, B, C, D, E, etc.) that is concise, easy to remember and allows detailed sub-division of climatic types.
Tambaya 6 Rahoto
(a) Outline five factors that should he considered in the location of an industry
(b) State five benefits of industrialization to a country
(a) Five factors to consider in the location of an industry
- Raw materials: nearness to the source, especially for bulky, heavy or perishable materials, to cut transport costs.
- Power/energy supply: availability of reliable electricity, gas or fuel to run machines.
- Market: nearness to the consumers of the product, especially for bulky, fragile or perishable finished goods.
- Labour: availability of enough skilled and unskilled workers at reasonable cost.
- Transport: good roads, railways, ports or waterways to move raw materials in and goods out.
- (Also: water supply, capital, land, and government policy.)
(b) Five benefits of industrialisation to a country
- Employment: industries create many jobs and reduce unemployment.
- Economic growth and income: they raise national income (GDP) and government revenue through taxes.
- Foreign exchange: export of manufactured goods earns foreign currency and reduces dependence on imports.
- Development of infrastructure: industrialisation brings roads, power, water and communications and stimulates towns.
- Diversification and self-reliance: it processes local raw materials, adds value, and reduces overdependence on primary products; it also promotes skills and technology.
Bayanin Amsa
(a) Five factors to consider in the location of an industry
- Raw materials: nearness to the source, especially for bulky, heavy or perishable materials, to cut transport costs.
- Power/energy supply: availability of reliable electricity, gas or fuel to run machines.
- Market: nearness to the consumers of the product, especially for bulky, fragile or perishable finished goods.
- Labour: availability of enough skilled and unskilled workers at reasonable cost.
- Transport: good roads, railways, ports or waterways to move raw materials in and goods out.
- (Also: water supply, capital, land, and government policy.)
(b) Five benefits of industrialisation to a country
- Employment: industries create many jobs and reduce unemployment.
- Economic growth and income: they raise national income (GDP) and government revenue through taxes.
- Foreign exchange: export of manufactured goods earns foreign currency and reduces dependence on imports.
- Development of infrastructure: industrialisation brings roads, power, water and communications and stimulates towns.
- Diversification and self-reliance: it processes local raw materials, adds value, and reduces overdependence on primary products; it also promotes skills and technology.
Tambaya 7 Rahoto
(a) Outline the problems of agricultural development in Nigeria.
(b) Suggest solutions to the problems outlined in (a) above.
(a) Problems of agricultural development in Nigeria
- Poor/traditional methods: reliance on crude tools (hoe and cutlass) and low technology gives low yields.
- Land tenure system: fragmented, communally owned holdings make large-scale mechanised farming difficult.
- Inadequate finance/credit: farmers lack capital and loans to buy inputs and machinery.
- Pests and diseases attack crops and livestock and reduce output.
- Poor storage and processing facilities, leading to heavy post-harvest losses.
- Unreliable rainfall and drought in the north, and flooding elsewhere.
- Poor transport and marketing, and low, fluctuating prices that discourage farmers.
- Rural-urban migration draining the young farm labour force, and shortage of extension services and improved inputs.
(b) Solutions to the problems
- Mechanise farming and supply improved seeds, fertilisers and modern tools to raise yields.
- Reform the land tenure system to allow access to larger farm holdings.
- Provide credit and finance through agricultural banks and government loan schemes.
- Control pests and diseases with chemicals, vaccination and research.
- Build storage, processing and preservation facilities to cut losses.
- Expand irrigation to overcome unreliable rainfall.
- Improve rural roads, transport and marketing, and guarantee fair prices.
- Strengthen extension services and training, and make farming attractive to check migration.
Bayanin Amsa
(a) Problems of agricultural development in Nigeria
- Poor/traditional methods: reliance on crude tools (hoe and cutlass) and low technology gives low yields.
- Land tenure system: fragmented, communally owned holdings make large-scale mechanised farming difficult.
- Inadequate finance/credit: farmers lack capital and loans to buy inputs and machinery.
- Pests and diseases attack crops and livestock and reduce output.
- Poor storage and processing facilities, leading to heavy post-harvest losses.
- Unreliable rainfall and drought in the north, and flooding elsewhere.
- Poor transport and marketing, and low, fluctuating prices that discourage farmers.
- Rural-urban migration draining the young farm labour force, and shortage of extension services and improved inputs.
(b) Solutions to the problems
- Mechanise farming and supply improved seeds, fertilisers and modern tools to raise yields.
- Reform the land tenure system to allow access to larger farm holdings.
- Provide credit and finance through agricultural banks and government loan schemes.
- Control pests and diseases with chemicals, vaccination and research.
- Build storage, processing and preservation facilities to cut losses.
- Expand irrigation to overcome unreliable rainfall.
- Improve rural roads, transport and marketing, and guarantee fair prices.
- Strengthen extension services and training, and make farming attractive to check migration.
Tambaya 8 Rahoto
(a) Draw an outline map of Nigeria. On the map. show and name:
(i) the position of Tropical Maritime air mass (S.W. Winds) in July:
(ii) the position of Inter Tropical Convergence Zone (I. T. C. Z) in July;
(iii) the relative position of Tropical Continental air mass (N. F. Winds) in July:
(iv) three towns located in (a.)(i) above.
(b) State four characteristics of the wet season in Nigeria.
(c) List two cash crops grown during the wet season in Nigeria.
(a) Outline map of Nigeria showing the air masses and the ITCZ in July
In July, moist Tropical Maritime (T.M.) south-westerly winds cover virtually the whole of Nigeria. The ITCZ lies north of Nigeria, approximately along latitude 20°N, and the dry Tropical Continental (T.C.) north-easterly winds are restricted to the area north of the ITCZ. Lagos, Ibadan and Enugu are shown within the area occupied by the T.M. air mass.
(b) Characteristics of the wet season in Nigeria
- The prevailing air mass is the moist Tropical Maritime air mass, which blows as south-westerly winds from the Atlantic Ocean.
- Rainfall is heavy and frequent, often accompanied by thunderstorms and squall lines.
- Relative humidity is high, generally about 80% to 100%, and cloud cover is extensive.
- Rainfall is greatest and lasts longest in the south, decreasing northwards. The south has a double rainfall maximum, with an August break, while the north has a single maximum.
(c) Two cash crops grown during the wet season in Nigeria
- Cocoa
- Oil palm
Bayanin Amsa
(a) Outline map of Nigeria showing the air masses and the ITCZ in July
In July, moist Tropical Maritime (T.M.) south-westerly winds cover virtually the whole of Nigeria. The ITCZ lies north of Nigeria, approximately along latitude 20°N, and the dry Tropical Continental (T.C.) north-easterly winds are restricted to the area north of the ITCZ. Lagos, Ibadan and Enugu are shown within the area occupied by the T.M. air mass.
(b) Characteristics of the wet season in Nigeria
- The prevailing air mass is the moist Tropical Maritime air mass, which blows as south-westerly winds from the Atlantic Ocean.
- Rainfall is heavy and frequent, often accompanied by thunderstorms and squall lines.
- Relative humidity is high, generally about 80% to 100%, and cloud cover is extensive.
- Rainfall is greatest and lasts longest in the south, decreasing northwards. The south has a double rainfall maximum, with an August break, while the north has a single maximum.
(c) Two cash crops grown during the wet season in Nigeria
- Cocoa
- Oil palm
Tambaya 9 Rahoto
(a) List four commodities exported from your country to any one European country.
(b) Outline four reasons for the low volume of trade among West African countries.
(c) Suggest four ways of improving trade ammo. West African countries.
(a) Four commodities exported from my country (Nigeria) to a European country (for example the United Kingdom)
- Crude petroleum (oil)
- Cocoa
- Rubber
- Tin and other solid minerals (also timber, hides and skins)
(b) Four reasons for the low volume of trade among West African countries
- Similar products: the countries produce and export the same primary goods (cocoa, groundnuts, palm produce, minerals), so they need one another's goods little and compete rather than trade.
- Poor transport links between the countries, with few good roads and rail lines connecting them, raising the cost of movement.
- Different currencies and colonial trade ties that bind each country more to Europe than to its neighbours.
- Trade barriers such as high tariffs, customs delays, language differences and border restrictions, plus smuggling and lack of industrial goods to exchange.
(c) Four ways of improving trade among West African countries
- Strengthen ECOWAS and remove tariffs and other trade barriers to form a free-trade area.
- Improve transport and communication - build international roads, railways and telecommunication links between the countries.
- Diversify economies and industrialise so that countries produce a wider range of goods to exchange.
- Adopt a common currency and harmonise trade policies, and set up joint industrial and marketing projects.
Bayanin Amsa
(a) Four commodities exported from my country (Nigeria) to a European country (for example the United Kingdom)
- Crude petroleum (oil)
- Cocoa
- Rubber
- Tin and other solid minerals (also timber, hides and skins)
(b) Four reasons for the low volume of trade among West African countries
- Similar products: the countries produce and export the same primary goods (cocoa, groundnuts, palm produce, minerals), so they need one another's goods little and compete rather than trade.
- Poor transport links between the countries, with few good roads and rail lines connecting them, raising the cost of movement.
- Different currencies and colonial trade ties that bind each country more to Europe than to its neighbours.
- Trade barriers such as high tariffs, customs delays, language differences and border restrictions, plus smuggling and lack of industrial goods to exchange.
(c) Four ways of improving trade among West African countries
- Strengthen ECOWAS and remove tariffs and other trade barriers to form a free-trade area.
- Improve transport and communication - build international roads, railways and telecommunication links between the countries.
- Diversify economies and industrialise so that countries produce a wider range of goods to exchange.
- Adopt a common currency and harmonise trade policies, and set up joint industrial and marketing projects.
Tambaya 10 Rahoto
(a)What are environmental hazards?
(b)List three examples of environmental hazards.
(c)Explain five ways of preventing desert encroachment.
(a) Meaning of environmental hazards
Environmental hazards are natural or human-induced events, processes or conditions in the environment that pose a threat to human life, property, economic activities and the natural landscape. They are potentially damaging occurrences within the biophysical environment that can result in loss of life, injury, destruction of property or disruption of social and economic life.
(b) Three examples of environmental hazards
- Flooding.
- Drought and desertification.
- Earthquakes (or volcanic eruptions, landslides, soil erosion, deforestation and pollution).
(c) Five ways of preventing desert encroachment
- Afforestation and reforestation: Planting trees and grasses over bare land binds the soil with roots, reduces wind speed at ground level and returns moisture to the atmosphere, so the desert margin is held back.
- Establishment of shelter belts (windbreaks): Rows of drought-resistant trees planted at right angles to the prevailing wind reduce wind erosion and prevent sand from being blown onto farmland and settlements.
- Control of overgrazing: Limiting the number of animals per unit of land and practising rotational grazing allows vegetation to recover, keeping the ground covered so that wind and sun cannot strip and dry the soil.
- Control of bush burning and deforestation: Enforcing laws against indiscriminate burning and tree felling preserves the protective vegetation cover that shields the soil from drying and erosion.
- Provision of irrigation and water conservation: Building dams, boreholes and irrigation channels supplies water to dry areas, enabling continuous cultivation and vegetation growth that hold the land against advancing sand.
Public enlightenment on land conservation and the use of alternative fuels (to reduce dependence on firewood) also help to check desert encroachment.
Bayanin Amsa
(a) Meaning of environmental hazards
Environmental hazards are natural or human-induced events, processes or conditions in the environment that pose a threat to human life, property, economic activities and the natural landscape. They are potentially damaging occurrences within the biophysical environment that can result in loss of life, injury, destruction of property or disruption of social and economic life.
(b) Three examples of environmental hazards
- Flooding.
- Drought and desertification.
- Earthquakes (or volcanic eruptions, landslides, soil erosion, deforestation and pollution).
(c) Five ways of preventing desert encroachment
- Afforestation and reforestation: Planting trees and grasses over bare land binds the soil with roots, reduces wind speed at ground level and returns moisture to the atmosphere, so the desert margin is held back.
- Establishment of shelter belts (windbreaks): Rows of drought-resistant trees planted at right angles to the prevailing wind reduce wind erosion and prevent sand from being blown onto farmland and settlements.
- Control of overgrazing: Limiting the number of animals per unit of land and practising rotational grazing allows vegetation to recover, keeping the ground covered so that wind and sun cannot strip and dry the soil.
- Control of bush burning and deforestation: Enforcing laws against indiscriminate burning and tree felling preserves the protective vegetation cover that shields the soil from drying and erosion.
- Provision of irrigation and water conservation: Building dams, boreholes and irrigation channels supplies water to dry areas, enabling continuous cultivation and vegetation growth that hold the land against advancing sand.
Public enlightenment on land conservation and the use of alternative fuels (to reduce dependence on firewood) also help to check desert encroachment.
