WAEC SSCE - Geography - 2005 (Essay)
Ajụjụ 1 Ripọtì
(a) Explain the term soil erosion
(b) Write notes on soil erosion under the following headings:
(i) causes (ii) effects (iii) methods of prevention
(a) Meaning of soil erosion
Soil erosion is the wearing away, loosening and removal of the top (surface) layer of the soil from one place to another by natural agents such as running water, wind, ice or waves, and often accelerated by human activities. It is most serious when the fertile topsoil is stripped away faster than it can be replaced.
(b) Notes on soil erosion
(i) Causes
- Heavy rainfall and steep slopes, which give fast-flowing run-off that carries soil away (sheet, rill and gully erosion).
- Removal of vegetation cover through deforestation, bush burning and overgrazing, leaving the soil bare and exposed.
- Poor farming methods such as ploughing up and down slopes, continuous cropping and shifting cultivation on fragile land.
- Strong winds in dry, bare areas that blow away loose soil particles.
(ii) Effects
- Loss of soil fertility as the nutrient-rich topsoil is removed, reducing crop yields.
- Formation of gullies and badlands that destroy farmland, roads and buildings.
- Silting of rivers, dams and reservoirs by the eroded material, causing flooding and shortening the life of dams.
- Desertification and migration as land becomes unproductive, forcing people to move away.
(iii) Methods of prevention
- Afforestation and re-vegetation to bind the soil with roots and break the force of rain and wind.
- Contour ploughing, terracing and strip cropping on slopes to slow down run-off.
- Cover cropping, mulching and crop rotation to keep the soil covered and maintain fertility.
- Building drainage channels, check dams and planting wind breaks (shelter belts), and controlling bush burning and overgrazing.
Akọwa Nkọwa
(a) Meaning of soil erosion
Soil erosion is the wearing away, loosening and removal of the top (surface) layer of the soil from one place to another by natural agents such as running water, wind, ice or waves, and often accelerated by human activities. It is most serious when the fertile topsoil is stripped away faster than it can be replaced.
(b) Notes on soil erosion
(i) Causes
- Heavy rainfall and steep slopes, which give fast-flowing run-off that carries soil away (sheet, rill and gully erosion).
- Removal of vegetation cover through deforestation, bush burning and overgrazing, leaving the soil bare and exposed.
- Poor farming methods such as ploughing up and down slopes, continuous cropping and shifting cultivation on fragile land.
- Strong winds in dry, bare areas that blow away loose soil particles.
(ii) Effects
- Loss of soil fertility as the nutrient-rich topsoil is removed, reducing crop yields.
- Formation of gullies and badlands that destroy farmland, roads and buildings.
- Silting of rivers, dams and reservoirs by the eroded material, causing flooding and shortening the life of dams.
- Desertification and migration as land becomes unproductive, forcing people to move away.
(iii) Methods of prevention
- Afforestation and re-vegetation to bind the soil with roots and break the force of rain and wind.
- Contour ploughing, terracing and strip cropping on slopes to slow down run-off.
- Cover cropping, mulching and crop rotation to keep the soil covered and maintain fertility.
- Building drainage channels, check dams and planting wind breaks (shelter belts), and controlling bush burning and overgrazing.
Ajụjụ 2 Ripọtì
(a) Draw a sketch map of Africa. On the map, show and name one area of any two of the following
(i) Equatorial climate;
(ii) Mediterranean climate;
(iii) Hot Desert climate;
(iv) Tropical Continental climate
(b) Highlight four characteristics of the Equatorial climate
(c) Outline three ways in which forest vegetation is of economic importance in Africa
(a) Sketch map of Africa showing two climatic areas
Key: green shading represents the Equatorial Climate in the Congo Basin; yellow shading represents the Hot Desert Climate in the Sahara.
(b) Characteristics of the Equatorial climate
- Temperatures are high throughout the year, averaging about 26°C to 27°C.
- The annual range of temperature is very small, usually about 2°C to 3°C.
- Rainfall is heavy and well distributed throughout the year, often reaching about 200 cm or more annually.
- There are usually two rainfall maxima, occurring around the equinoxes.
- Most rainfall is convectional and commonly falls as heavy afternoon showers accompanied by thunder and lightning.
- Relative humidity is high throughout the year and cloud cover is extensive.
(c) Economic importance of forest vegetation in Africa
- It supplies valuable hardwood and timber for building, furniture making, paper and other industries.
- Lumbering, sawmilling and the sale of timber provide employment, income and foreign exchange.
- Forests provide fuel wood and charcoal for domestic and industrial use.
- They supply raw materials and useful products such as rubber, fruits, nuts, palm products and medicinal herbs.
- Forest reserves conserve wildlife and provide sites for tourism and recreation.
Akọwa Nkọwa
(a) Sketch map of Africa showing two climatic areas
Key: green shading represents the Equatorial Climate in the Congo Basin; yellow shading represents the Hot Desert Climate in the Sahara.
(b) Characteristics of the Equatorial climate
- Temperatures are high throughout the year, averaging about 26°C to 27°C.
- The annual range of temperature is very small, usually about 2°C to 3°C.
- Rainfall is heavy and well distributed throughout the year, often reaching about 200 cm or more annually.
- There are usually two rainfall maxima, occurring around the equinoxes.
- Most rainfall is convectional and commonly falls as heavy afternoon showers accompanied by thunder and lightning.
- Relative humidity is high throughout the year and cloud cover is extensive.
(c) Economic importance of forest vegetation in Africa
- It supplies valuable hardwood and timber for building, furniture making, paper and other industries.
- Lumbering, sawmilling and the sale of timber provide employment, income and foreign exchange.
- Forests provide fuel wood and charcoal for domestic and industrial use.
- They supply raw materials and useful products such as rubber, fruits, nuts, palm products and medicinal herbs.
- Forest reserves conserve wildlife and provide sites for tourism and recreation.
Ajụjụ 3 Ripọtì
(a) List three plantation crops in Africa
(b) Outline four ways in which plantation agriculture is important
(c) Highlight three differences between plantation agriculture in West Africa and East Africa
(a) Three plantation crops in Africa
- Cocoa.
- Oil palm.
- Rubber.
(Others acceptable: coffee, tea, sugar cane, banana, sisal.)
(b) Four ways in which plantation agriculture is important
- Foreign-exchange earnings: plantation crops such as cocoa, coffee, tea and rubber are exported and bring in foreign currency.
- Employment: plantations provide large-scale jobs for many workers in growing, harvesting and processing.
- Raw materials for industry: they supply factories (for example oil palm for oil and margarine, rubber for tyres), encouraging industrial growth.
- Development of infrastructure and rural areas: roads, railways, health and housing facilities are provided, and the crops widen and diversify the economy.
(c) Three differences between plantation agriculture in West Africa and East Africa
| West Africa | East Africa |
|---|---|
| Mostly lowland/coastal crops such as oil palm, cocoa and rubber. | Mostly highland crops such as tea, coffee and sisal grown on the cooler plateaux. |
| A large share of output comes from smallholder/peasant farmers alongside plantations. | Large European/foreign-owned estates played a bigger role in the plantation system. |
| Grown mainly in the hot, wet equatorial/forest lowlands. | Grown mainly on the high, cooler and well-drained volcanic uplands. |
Akọwa Nkọwa
(a) Three plantation crops in Africa
- Cocoa.
- Oil palm.
- Rubber.
(Others acceptable: coffee, tea, sugar cane, banana, sisal.)
(b) Four ways in which plantation agriculture is important
- Foreign-exchange earnings: plantation crops such as cocoa, coffee, tea and rubber are exported and bring in foreign currency.
- Employment: plantations provide large-scale jobs for many workers in growing, harvesting and processing.
- Raw materials for industry: they supply factories (for example oil palm for oil and margarine, rubber for tyres), encouraging industrial growth.
- Development of infrastructure and rural areas: roads, railways, health and housing facilities are provided, and the crops widen and diversify the economy.
(c) Three differences between plantation agriculture in West Africa and East Africa
| West Africa | East Africa |
|---|---|
| Mostly lowland/coastal crops such as oil palm, cocoa and rubber. | Mostly highland crops such as tea, coffee and sisal grown on the cooler plateaux. |
| A large share of output comes from smallholder/peasant farmers alongside plantations. | Large European/foreign-owned estates played a bigger role in the plantation system. |
| Grown mainly in the hot, wet equatorial/forest lowlands. | Grown mainly on the high, cooler and well-drained volcanic uplands. |
Ajụjụ 4 Ripọtì
(a) Draw an outline map of Africa. On the map, locate and name,
(i) one are important for the mining of each of coal, diamond and Old;
(ii) one important town in two of the areas in (a)(i) above
(b) Highlight three ways in which the minerals in (a)(i) above are of economic importance to Africa.
(c) Outline two problems associated with mining in Africa.
(a) Outline map of Africa showing mineral areas and towns
Key to the map
- Coal: Witbank (Emalahleni) coalfield, South Africa.
- Diamond: Kimberley, South Africa.
- Gold: Witwatersrand, South Africa.
- Towns named: Johannesburg in the Witwatersrand gold-mining area, and Kimberley in the diamond-mining area.
(b) Economic importance of the minerals to Africa
- Gold and diamonds are exported to earn foreign exchange and increase government revenue.
- Coal supplies energy for thermal power generation, rail transport and industries.
- Mining provides employment and promotes the growth of mining towns, roads, railways and related industries.
(c) Problems associated with mining in Africa
- Mining is capital-intensive: machinery, skilled labour and modern technology are often inadequate or expensive.
- Mining causes environmental hazards such as land degradation, destruction of vegetation, open pits and pollution of water and air.
Akọwa Nkọwa
(a) Outline map of Africa showing mineral areas and towns
Key to the map
- Coal: Witbank (Emalahleni) coalfield, South Africa.
- Diamond: Kimberley, South Africa.
- Gold: Witwatersrand, South Africa.
- Towns named: Johannesburg in the Witwatersrand gold-mining area, and Kimberley in the diamond-mining area.
(b) Economic importance of the minerals to Africa
- Gold and diamonds are exported to earn foreign exchange and increase government revenue.
- Coal supplies energy for thermal power generation, rail transport and industries.
- Mining provides employment and promotes the growth of mining towns, roads, railways and related industries.
(c) Problems associated with mining in Africa
- Mining is capital-intensive: machinery, skilled labour and modern technology are often inadequate or expensive.
- Mining causes environmental hazards such as land degradation, destruction of vegetation, open pits and pollution of water and air.
Ajụjụ 5 Ripọtì
(a) Define the following terms:
(i) optimum population;
(ii) over-population;
(iii) population density
(b) The total population of country Q in the year 1998 was 4 million. If the land area of country Q is 400,000 km2, calculate the population density of country Q
(c) Highlight four disadvantages of the population density calculated in (b) above on the economy of country
(a) Definitions
- (i) Optimum population: the ideal population size that, with the available resources and level of technology, gives the highest standard of living (the greatest output and welfare per person). It is neither too many nor too few people for the resources.
- (ii) Over-population: a situation in which the population is too large for the available resources and technology to support at a reasonable standard of living, so that resources are over-stretched and welfare falls.
- (iii) Population density: the average number of people living on each unit area of land, usually expressed as persons per square kilometre. It is found by dividing the total population by the total land area.
(b) Population density of country Q
\[\text{Population density} = \frac{\text{Total population}}{\text{Land area}}\]
\[= \frac{4\,000\,000}{400\,000} = 10 \text{ persons per km}^2\]
Population density = 10 persons per km2 (a low/sparse density).
(c) Four disadvantages of this low population density on the economy of the country
- Shortage of labour: too few people to work the farms, mines and industries, so resources remain unused or under-developed.
- Small home market: low demand for goods and services discourages large-scale production and investment.
- High cost of infrastructure per head: roads, water, electricity and other services are expensive to provide and maintain for a thinly spread population.
- Weak revenue and slow development: a small population yields little tax revenue and a small workforce, so defence, government services and the general pace of economic growth suffer.
Akọwa Nkọwa
(a) Definitions
- (i) Optimum population: the ideal population size that, with the available resources and level of technology, gives the highest standard of living (the greatest output and welfare per person). It is neither too many nor too few people for the resources.
- (ii) Over-population: a situation in which the population is too large for the available resources and technology to support at a reasonable standard of living, so that resources are over-stretched and welfare falls.
- (iii) Population density: the average number of people living on each unit area of land, usually expressed as persons per square kilometre. It is found by dividing the total population by the total land area.
(b) Population density of country Q
\[\text{Population density} = \frac{\text{Total population}}{\text{Land area}}\]
\[= \frac{4\,000\,000}{400\,000} = 10 \text{ persons per km}^2\]
Population density = 10 persons per km2 (a low/sparse density).
(c) Four disadvantages of this low population density on the economy of the country
- Shortage of labour: too few people to work the farms, mines and industries, so resources remain unused or under-developed.
- Small home market: low demand for goods and services discourages large-scale production and investment.
- High cost of infrastructure per head: roads, water, electricity and other services are expensive to provide and maintain for a thinly spread population.
- Weak revenue and slow development: a small population yields little tax revenue and a small workforce, so defence, government services and the general pace of economic growth suffer.
Ajụjụ 6 Ripọtì
Study the map extract on a scale of 1:50,000 and answer the following questions
(a) On the map extract:
(I) Print the letters shown in the brackets below on one example of each of the following features: Conical Peak (CP) Narrow River Valley (NRV) Even Slope (ES)
(b) Calculate the gradient of the minor road from the road junction in Sabongidda to the Church in Aviosi
(c) Describe the location and functions of uhomora
(a) Printing the letters on the map
- Conical Peak (CP): print in the north-east, on the hill whose contour rings are roughly circular and close together, tapering to a single high point (the ground above 750 ft).
- Narrow River Valley (NRV): print in the south-west, where the contours form a sharp V enclosing a stream.
- Even Slope (ES): print in the eastern part, where the contours are equally spaced, showing a uniform gradient.
(b) Gradient of the minor road from the Sabongidda junction to the church in Aviosi
Height at the Sabongidda road junction \(=250\text{ ft}\); height at the church in Aviosi \(=675\text{ ft}\).
\[\text{Vertical interval}=675-250=425\text{ ft}.\]Road distance measured on the map \(=5.9\text{ in}\). Since \(1\text{ mile}=5280\text{ ft}\) and the scale is 1:50,000 (1.25 in to 1 mile):
\[\text{Horizontal equivalent}=\frac{5.9}{1.25}=4.7\text{ miles}=4.7\times5280=24\,816\text{ ft}.\]\[\text{Gradient}=\frac{\text{Vertical interval}}{\text{Horizontal equivalent}}=\frac{425}{24\,816}=\frac{1}{58}.\]The gradient of the minor road is 1 in 58 (1:58).
(c) Location and functions of Uhomora
Location: Uhomora lies in the south-east of the map, on the spur between two tributaries of River Onwan, on level ground between the 250 ft and 300 ft contours.
Functions:
- It is a nodal town, being the meeting point of two minor roads.
- It performs a medical function, shown by the hospital and dispensary.
- It performs an educational function, shown by the schools.
- It performs a religious function, shown by the churches.
Akọwa Nkọwa
(a) Printing the letters on the map
- Conical Peak (CP): print in the north-east, on the hill whose contour rings are roughly circular and close together, tapering to a single high point (the ground above 750 ft).
- Narrow River Valley (NRV): print in the south-west, where the contours form a sharp V enclosing a stream.
- Even Slope (ES): print in the eastern part, where the contours are equally spaced, showing a uniform gradient.
(b) Gradient of the minor road from the Sabongidda junction to the church in Aviosi
Height at the Sabongidda road junction \(=250\text{ ft}\); height at the church in Aviosi \(=675\text{ ft}\).
\[\text{Vertical interval}=675-250=425\text{ ft}.\]Road distance measured on the map \(=5.9\text{ in}\). Since \(1\text{ mile}=5280\text{ ft}\) and the scale is 1:50,000 (1.25 in to 1 mile):
\[\text{Horizontal equivalent}=\frac{5.9}{1.25}=4.7\text{ miles}=4.7\times5280=24\,816\text{ ft}.\]\[\text{Gradient}=\frac{\text{Vertical interval}}{\text{Horizontal equivalent}}=\frac{425}{24\,816}=\frac{1}{58}.\]The gradient of the minor road is 1 in 58 (1:58).
(c) Location and functions of Uhomora
Location: Uhomora lies in the south-east of the map, on the spur between two tributaries of River Onwan, on level ground between the 250 ft and 300 ft contours.
Functions:
- It is a nodal town, being the meeting point of two minor roads.
- It performs a medical function, shown by the hospital and dispensary.
- It performs an educational function, shown by the schools.
- It performs a religious function, shown by the churches.
Ajụjụ 7 Ripọtì
(a) Draw a sketch map of Nigeria. On the map, locate and name'
(i) the Mid-West industrial zone;
(ii) the South-East industrial zone'
(iii) the North-Central industrial zone;
(iv) one important town in each zone in (a)(i) — (iii) above
(b) Highlight three problems faci,ng manufacturing industries in Nigeria.
(c) Suggest solutions to any two of the problems highlighted in 5(b) above
(a) Sketch map of Nigeria showing the industrial zones
Key: MW = Mid-West industrial zone; SE = South-East industrial zone; NC = North-Central industrial zone.
- Mid-West industrial zone: the Benin City, Sapele and Warri area. Important town: Warri.
- South-East industrial zone: the Enugu, Onitsha, Aba and Port Harcourt area. Important town: Aba.
- North-Central industrial zone: the Kaduna, Zaria and Jos area. Important town: Kaduna.
(b) Problems facing manufacturing industries in Nigeria
- Erratic power supply: Industries spend heavily on generators and fuel when public electricity supply fails.
- Inadequate capital: Many manufacturers cannot obtain sufficient long-term loans to buy machinery, raw materials or expand production.
- Dependence on imported raw materials, machinery and spare parts: Foreign exchange shortages and high import costs raise production costs and interrupt production.
(c) Solutions to two of the problems
- Improving power supply: Government and private power producers should expand electricity generation, transmission and distribution, while industries can use reliable alternative energy sources such as gas and solar power.
- Providing capital and local inputs: Banks and government should provide low-interest industrial loans and tax incentives. Local raw materials should be developed, while local fabrication of machinery and spare parts should be encouraged to reduce import dependence.
Akọwa Nkọwa
(a) Sketch map of Nigeria showing the industrial zones
Key: MW = Mid-West industrial zone; SE = South-East industrial zone; NC = North-Central industrial zone.
- Mid-West industrial zone: the Benin City, Sapele and Warri area. Important town: Warri.
- South-East industrial zone: the Enugu, Onitsha, Aba and Port Harcourt area. Important town: Aba.
- North-Central industrial zone: the Kaduna, Zaria and Jos area. Important town: Kaduna.
(b) Problems facing manufacturing industries in Nigeria
- Erratic power supply: Industries spend heavily on generators and fuel when public electricity supply fails.
- Inadequate capital: Many manufacturers cannot obtain sufficient long-term loans to buy machinery, raw materials or expand production.
- Dependence on imported raw materials, machinery and spare parts: Foreign exchange shortages and high import costs raise production costs and interrupt production.
(c) Solutions to two of the problems
- Improving power supply: Government and private power producers should expand electricity generation, transmission and distribution, while industries can use reliable alternative energy sources such as gas and solar power.
- Providing capital and local inputs: Banks and government should provide low-interest industrial loans and tax incentives. Local raw materials should be developed, while local fabrication of machinery and spare parts should be encouraged to reduce import dependence.
Ajụjụ 8 Ripọtì
(a) Define the term Vulcanicity
(b) Describe the mode of formation and appearance of a volcanic plateau
(c) Highlight four effects of Vulcanicity
(a) Meaning of Vulcanicity
Vulcanicity (vulcanism) is the process by which molten rock (magma), gases and other volcanic materials from the interior of the Earth are forced towards or onto the surface. It includes both intrusive activity (magma cooling within the crust to form features such as batholiths, dykes, sills and laccoliths) and extrusive activity (lava and materials reaching the surface to form volcanoes, lava plateaux and geysers).
(b) Formation and appearance of a volcanic (lava) plateau
Mode of formation: A volcanic plateau is formed by fissure eruptions. Very fluid, basic (basaltic) lava wells up quietly through long cracks or fissures in the crust rather than from a single vent. Because the lava is thin and runny, it spreads out over a wide area before cooling. Repeated eruptions build up layer upon layer of solidified lava (basalt) until a thick, extensive, raised, flat-topped upland is formed.
Appearance: It appears as a broad, high, almost level or gently undulating tableland with steep edges. It is built of horizontal sheets (layers) of basalt, and rivers later cut deep gorges and valleys into it. Examples include the Jos Plateau region basalts, the Ethiopian (Abyssinian) Plateau and the Deccan Plateau of India.
(c) Four effects of Vulcanicity
- Fertile soils: weathered volcanic (lava) materials give rich soils good for farming crops such as coffee, tea and cocoa.
- Landform and scenic value: it creates mountains, plateaux, crater lakes and hot springs that attract tourists.
- Mineral and geothermal resources: volcanic areas yield useful minerals and provide geothermal energy (steam/hot springs) that can generate electricity.
- Hazards: violent eruptions destroy life, farmland and property, and can cause earthquakes and force people to migrate.
Akọwa Nkọwa
(a) Meaning of Vulcanicity
Vulcanicity (vulcanism) is the process by which molten rock (magma), gases and other volcanic materials from the interior of the Earth are forced towards or onto the surface. It includes both intrusive activity (magma cooling within the crust to form features such as batholiths, dykes, sills and laccoliths) and extrusive activity (lava and materials reaching the surface to form volcanoes, lava plateaux and geysers).
(b) Formation and appearance of a volcanic (lava) plateau
Mode of formation: A volcanic plateau is formed by fissure eruptions. Very fluid, basic (basaltic) lava wells up quietly through long cracks or fissures in the crust rather than from a single vent. Because the lava is thin and runny, it spreads out over a wide area before cooling. Repeated eruptions build up layer upon layer of solidified lava (basalt) until a thick, extensive, raised, flat-topped upland is formed.
Appearance: It appears as a broad, high, almost level or gently undulating tableland with steep edges. It is built of horizontal sheets (layers) of basalt, and rivers later cut deep gorges and valleys into it. Examples include the Jos Plateau region basalts, the Ethiopian (Abyssinian) Plateau and the Deccan Plateau of India.
(c) Four effects of Vulcanicity
- Fertile soils: weathered volcanic (lava) materials give rich soils good for farming crops such as coffee, tea and cocoa.
- Landform and scenic value: it creates mountains, plateaux, crater lakes and hot springs that attract tourists.
- Mineral and geothermal resources: volcanic areas yield useful minerals and provide geothermal energy (steam/hot springs) that can generate electricity.
- Hazards: violent eruptions destroy life, farmland and property, and can cause earthquakes and force people to migrate.
Ajụjụ 9 Ripọtì
(a) Highlight three advantages-and three disadvantages of water transport
(b) Explain any four factors-that hinder the use of water transport
(a) Advantages and disadvantages of water transport
Three advantages:
- Cheapest for bulky goods: ships and barges can carry very large, heavy cargoes (oil, grain, ores) over long distances at low cost per tonne.
- Natural, ready-made routes: seas, oceans, rivers and lakes provide free routeways, so little construction is needed compared with roads and railways.
- Low fuel and maintenance cost per unit carried, and it links many countries and continents, promoting international trade.
Three disadvantages:
- Very slow, so it is unsuitable for perishable goods and urgent deliveries.
- Limited routes: it can serve only places on or near navigable water, and needs feeder transport to reach inland destinations.
- Affected by weather and needs costly port facilities; storms, fog, ice and shallow water can delay or endanger vessels.
(b) Four factors that hinder the use of water transport
- Shallow water, rapids, waterfalls and sand bars that block or interrupt navigation on rivers.
- Seasonal changes in water level (low water in the dry season, floods in the wet season) that make some rivers navigable only part of the year.
- Silting of channels, ports and river mouths, and the growth of aquatic weeds, which obstruct vessels.
- Freezing of rivers and lakes in cold regions, and adverse weather such as storms and fog; also the high cost of dredging and building/maintaining harbours.
Akọwa Nkọwa
(a) Advantages and disadvantages of water transport
Three advantages:
- Cheapest for bulky goods: ships and barges can carry very large, heavy cargoes (oil, grain, ores) over long distances at low cost per tonne.
- Natural, ready-made routes: seas, oceans, rivers and lakes provide free routeways, so little construction is needed compared with roads and railways.
- Low fuel and maintenance cost per unit carried, and it links many countries and continents, promoting international trade.
Three disadvantages:
- Very slow, so it is unsuitable for perishable goods and urgent deliveries.
- Limited routes: it can serve only places on or near navigable water, and needs feeder transport to reach inland destinations.
- Affected by weather and needs costly port facilities; storms, fog, ice and shallow water can delay or endanger vessels.
(b) Four factors that hinder the use of water transport
- Shallow water, rapids, waterfalls and sand bars that block or interrupt navigation on rivers.
- Seasonal changes in water level (low water in the dry season, floods in the wet season) that make some rivers navigable only part of the year.
- Silting of channels, ports and river mouths, and the growth of aquatic weeds, which obstruct vessels.
- Freezing of rivers and lakes in cold regions, and adverse weather such as storms and fog; also the high cost of dredging and building/maintaining harbours.
Ajụjụ 10 Ripọtì
(a) if the time in London is 08.00 hours GMT and the local time in Addis Ababa is 12.00 noon on what longitude ts Addis Ababa?
(b) Write explanatory notes on the following:
(i) Time zones; (ii) Standard Times; (iii) International Dateline
(a) Longitude of Addis Ababa
The Earth turns \(360^\circ\) in 24 hours, so \(1\) hour of time = \(15^\circ\) of longitude.
Time difference between Addis Ababa (12:00 noon) and London (08:00 GMT):
\[12:00 - 08:00 = 4 \text{ hours}\]
Longitude difference:
\[4 \times 15^\circ = 60^\circ\]
Because Addis Ababa is ahead of GMT (its clock reads later than London's), it lies east of the Greenwich Meridian.
Addis Ababa is on longitude \(60^\circ E\).
(b) Explanatory notes
(i) Time zones: A time zone is a belt of the Earth's surface, about \(15^\circ\) of longitude wide, that keeps the same clock time. The world is divided into 24 such zones (each 1 hour apart) so that places within a zone use one convenient standard time instead of a slightly different local time at every meridian.
(ii) Standard time: This is the single, uniform clock time adopted by a whole country or zone, usually based on a chosen central meridian. It saves the confusion of many local times; large countries that stretch across several meridians (such as the USA or Russia) adopt more than one standard time.
(iii) International Date Line: This is the imaginary line drawn mainly along the \(180^\circ\) meridian in the Pacific Ocean where the date changes. A traveller crossing it going westward (eastern to western hemisphere) gains a day (moves the calendar forward), while going eastward loses a day. The line is bent in places to avoid splitting land areas and island groups into two different dates.
Akọwa Nkọwa
(a) Longitude of Addis Ababa
The Earth turns \(360^\circ\) in 24 hours, so \(1\) hour of time = \(15^\circ\) of longitude.
Time difference between Addis Ababa (12:00 noon) and London (08:00 GMT):
\[12:00 - 08:00 = 4 \text{ hours}\]
Longitude difference:
\[4 \times 15^\circ = 60^\circ\]
Because Addis Ababa is ahead of GMT (its clock reads later than London's), it lies east of the Greenwich Meridian.
Addis Ababa is on longitude \(60^\circ E\).
(b) Explanatory notes
(i) Time zones: A time zone is a belt of the Earth's surface, about \(15^\circ\) of longitude wide, that keeps the same clock time. The world is divided into 24 such zones (each 1 hour apart) so that places within a zone use one convenient standard time instead of a slightly different local time at every meridian.
(ii) Standard time: This is the single, uniform clock time adopted by a whole country or zone, usually based on a chosen central meridian. It saves the confusion of many local times; large countries that stretch across several meridians (such as the USA or Russia) adopt more than one standard time.
(iii) International Date Line: This is the imaginary line drawn mainly along the \(180^\circ\) meridian in the Pacific Ocean where the date changes. A traveller crossing it going westward (eastern to western hemisphere) gains a day (moves the calendar forward), while going eastward loses a day. The line is bent in places to avoid splitting land areas and island groups into two different dates.
Ajụjụ 11 Ripọtì
(a) State any four factors that determine the temperature of a place
(b) (i) List the two climatic elements used as the basis of Koppen's classification
(ii) Identify the main climatic groups in Koppen's climatic classification
(a) Four factors that determine the temperature of a place
- Latitude: places near the Equator receive the Sun's rays more directly and are hotter than places near the poles where the rays are slanting.
- Altitude: temperature falls with height (about \(6.5^\circ C\) per 1000 m), so highlands are cooler than lowlands on the same latitude.
- Distance from the sea (continentality): coastal places have milder, more even temperatures because the sea heats and cools slowly, while inland places have hotter days and colder nights.
- Ocean currents and prevailing winds: warm currents/winds raise temperature and cold currents/winds lower it (also acceptable: cloud cover, nature of the surface/vegetation, and aspect).
(b) Koppen's climatic classification
(i) The two climatic elements used as the basis:
- Temperature and Precipitation (rainfall).
(Koppen combined these with the natural vegetation of each region.)
(ii) The main climatic groups in Koppen's classification:
- A - Tropical (hot, wet) climates.
- B - Dry (arid and semi-arid/desert and steppe) climates.
- C - Warm temperate (mild, mid-latitude) climates.
- D - Cold temperate (cold, snowy, mid-latitude/continental) climates.
- E - Polar (cold, ice and tundra) climates.
(Some versions add H - Highland/mountain climates.)
Akọwa Nkọwa
(a) Four factors that determine the temperature of a place
- Latitude: places near the Equator receive the Sun's rays more directly and are hotter than places near the poles where the rays are slanting.
- Altitude: temperature falls with height (about \(6.5^\circ C\) per 1000 m), so highlands are cooler than lowlands on the same latitude.
- Distance from the sea (continentality): coastal places have milder, more even temperatures because the sea heats and cools slowly, while inland places have hotter days and colder nights.
- Ocean currents and prevailing winds: warm currents/winds raise temperature and cold currents/winds lower it (also acceptable: cloud cover, nature of the surface/vegetation, and aspect).
(b) Koppen's climatic classification
(i) The two climatic elements used as the basis:
- Temperature and Precipitation (rainfall).
(Koppen combined these with the natural vegetation of each region.)
(ii) The main climatic groups in Koppen's classification:
- A - Tropical (hot, wet) climates.
- B - Dry (arid and semi-arid/desert and steppe) climates.
- C - Warm temperate (mild, mid-latitude) climates.
- D - Cold temperate (cold, snowy, mid-latitude/continental) climates.
- E - Polar (cold, ice and tundra) climates.
(Some versions add H - Highland/mountain climates.)
Ajụjụ 12 Ripọtì
(a) Draw an outline map of Nigeria. On the map, locate and name;
(i) the Gulf of Guinea; (ii) the Bight of Bonny; (iii) latitude 14°N; (iv) the country to the Western border; (v) the Federal Capital Territory
(b) Describe the size and location if Nigeria in relation to other countries of West Africa
(a) Outline map of Nigeria
(b) Size and location of Nigeria in relation to other countries of West Africa
Size
- Nigeria has a land area of about 923,768 km².
- It is the fourth largest country in West Africa by land area, after Niger, Mali and Mauritania.
- It occupies approximately one-seventh of the total area of West Africa.
- It is about four times the size of Ghana and about thirteen times the size of Sierra Leone.
- Its greatest east-west extent is about 1,300 km, while its north-south extent is about 1,100 km.
- It is the most populous country in West Africa.
Location
- Nigeria is located in the central/eastern part of West Africa, on the coast of the Gulf of Guinea.
- It lies approximately between latitudes 4°N and 14°N, and longitudes 3°E and 15°E.
- It is bounded by the Republic of Benin to the west, Niger to the north, Chad to the north-east across Lake Chad, and Cameroon to the east.
- To the south, Nigeria is bounded by the Atlantic Ocean, particularly the Gulf of Guinea. The Bight of Bonny lies along its south-eastern coast.
Akọwa Nkọwa
(a) Outline map of Nigeria
(b) Size and location of Nigeria in relation to other countries of West Africa
Size
- Nigeria has a land area of about 923,768 km².
- It is the fourth largest country in West Africa by land area, after Niger, Mali and Mauritania.
- It occupies approximately one-seventh of the total area of West Africa.
- It is about four times the size of Ghana and about thirteen times the size of Sierra Leone.
- Its greatest east-west extent is about 1,300 km, while its north-south extent is about 1,100 km.
- It is the most populous country in West Africa.
Location
- Nigeria is located in the central/eastern part of West Africa, on the coast of the Gulf of Guinea.
- It lies approximately between latitudes 4°N and 14°N, and longitudes 3°E and 15°E.
- It is bounded by the Republic of Benin to the west, Niger to the north, Chad to the north-east across Lake Chad, and Cameroon to the east.
- To the south, Nigeria is bounded by the Atlantic Ocean, particularly the Gulf of Guinea. The Bight of Bonny lies along its south-eastern coast.
Ajụjụ 13 Ripọtì
(a) Describe three characteristics of forest vegetation
(b) Outline three ways in which vegetation is important as an environmental resource
(c) Highlight two problems that may arise from over-utilization of vegetation resources
(a) Three characteristics of forest vegetation
- Trees dominate and grow tall, forming a closed or nearly closed canopy so that the ground receives little sunlight.
- Layered (storeyed) structure, with emergent tall trees, a main canopy layer, and lower shrub and ground layers.
- Dense and varied plant life, many species of hardwood trees mixed together, with climbers (lianas), epiphytes and, in wet forests, broad evergreen leaves; the trees often have buttress roots.
(b) Three ways vegetation is important as an environmental resource
- Protects the soil and water: it binds the soil with roots, checks erosion, and helps rainfall to soak in, keeping rivers and springs supplied.
- Regulates climate and air quality: plants take in carbon dioxide and give out oxygen, add moisture to the air, and moderate temperature, reducing the greenhouse effect.
- Habitat and raw materials: it provides a home for wildlife and supplies timber, fuel wood, medicines, fruits and grazing, which support human livelihood.
(c) Two problems from over-utilization of vegetation resources
- Deforestation leading to soil erosion and loss of fertility, flooding, silting of rivers and eventual desertification.
- Destruction of habitat and loss of biodiversity, so that wildlife and useful plant species become scarce or extinct, and the climate is disturbed.
Akọwa Nkọwa
(a) Three characteristics of forest vegetation
- Trees dominate and grow tall, forming a closed or nearly closed canopy so that the ground receives little sunlight.
- Layered (storeyed) structure, with emergent tall trees, a main canopy layer, and lower shrub and ground layers.
- Dense and varied plant life, many species of hardwood trees mixed together, with climbers (lianas), epiphytes and, in wet forests, broad evergreen leaves; the trees often have buttress roots.
(b) Three ways vegetation is important as an environmental resource
- Protects the soil and water: it binds the soil with roots, checks erosion, and helps rainfall to soak in, keeping rivers and springs supplied.
- Regulates climate and air quality: plants take in carbon dioxide and give out oxygen, add moisture to the air, and moderate temperature, reducing the greenhouse effect.
- Habitat and raw materials: it provides a home for wildlife and supplies timber, fuel wood, medicines, fruits and grazing, which support human livelihood.
(c) Two problems from over-utilization of vegetation resources
- Deforestation leading to soil erosion and loss of fertility, flooding, silting of rivers and eventual desertification.
- Destruction of habitat and loss of biodiversity, so that wildlife and useful plant species become scarce or extinct, and the climate is disturbed.
Ajụjụ 14 Ripọtì
(a) Explain the term error of closure
(b) Highlight any four sources of error of closure in closed traverse survey
(c) Outline two meaures that could be taken to avoid an error of closure
(a) Meaning of error of closure
In a closed traverse the survey lines are run round an area and should end exactly at the starting point. The error of closure is the small gap or difference between the true starting point and the point at which the survey actually closes when it is plotted, that is, the amount by which the survey fails to close back onto its origin. It shows the total accumulated error of the survey.
(b) Four sources of error of closure in a closed traverse survey
- Instrumental errors: a faulty or wrongly graduated chain/tape, a badly adjusted compass or theodolite, or a bent ranging pole.
- Errors in measuring angles/bearings: wrong reading of the compass or theodolite, local magnetic attraction affecting the needle, or failing to take the back bearing.
- Errors in measuring distances: inaccurate chaining, sag or stretch in the tape, sloping ground not corrected to the horizontal, or miscounting the chains/arrows.
- Personal (human) and plotting errors: careless booking, mistakes in recording figures, and errors made when plotting the survey on paper (wrong scale, poor drawing).
(c) Two measures to avoid an error of closure
- Check and adjust the instruments before use and take readings carefully, repeating and averaging measurements of both distances and angles.
- Apply proper field checks such as measuring back bearings, using check lines/tie lines, and keeping away from sources of magnetic disturbance; any small residual error is then distributed by adjustment (for example the Bowditch rule) when plotting.
Akọwa Nkọwa
(a) Meaning of error of closure
In a closed traverse the survey lines are run round an area and should end exactly at the starting point. The error of closure is the small gap or difference between the true starting point and the point at which the survey actually closes when it is plotted, that is, the amount by which the survey fails to close back onto its origin. It shows the total accumulated error of the survey.
(b) Four sources of error of closure in a closed traverse survey
- Instrumental errors: a faulty or wrongly graduated chain/tape, a badly adjusted compass or theodolite, or a bent ranging pole.
- Errors in measuring angles/bearings: wrong reading of the compass or theodolite, local magnetic attraction affecting the needle, or failing to take the back bearing.
- Errors in measuring distances: inaccurate chaining, sag or stretch in the tape, sloping ground not corrected to the horizontal, or miscounting the chains/arrows.
- Personal (human) and plotting errors: careless booking, mistakes in recording figures, and errors made when plotting the survey on paper (wrong scale, poor drawing).
(c) Two measures to avoid an error of closure
- Check and adjust the instruments before use and take readings carefully, repeating and averaging measurements of both distances and angles.
- Apply proper field checks such as measuring back bearings, using check lines/tie lines, and keeping away from sources of magnetic disturbance; any small residual error is then distributed by adjustment (for example the Bowditch rule) when plotting.
Ajụjụ 15 Ripọtì
(a) Explain the term karsi topography
(b) Name any four features found in karst regions
(c) Highlight five characteristics of karst regions
(a) Meaning of karst topography
Karst topography is the distinctive scenery that develops in regions of thick, well-jointed limestone (or other soluble rock such as dolomite or chalk) as a result of solution (carbonation) weathering. Rainwater, being a weak carbonic acid, dissolves the limestone along its joints and cracks, producing a landscape of underground drainage with characteristic surface and underground features. The name comes from the Karst region of the former Yugoslavia.
(b) Four features found in karst regions
- Swallow holes (sink holes / dolines).
- Limestone caves and caverns.
- Stalactites and stalagmites (in the caves).
- Limestone pavements with clints and grikes; also gorges and underground streams.
(c) Five characteristics of karst regions
- Underground drainage: surface streams disappear down swallow holes and flow underground, so the surface is often dry.
- Presence of caves and caverns formed by solution beneath the surface, decorated with stalactites (hanging from the roof) and stalagmites (rising from the floor).
- Bare, rocky surface with limestone pavements (clints separated by grikes) and thin, poor soils, so vegetation is scanty.
- Numerous joints and cracks in the well-bedded limestone along which solution takes place; enlarged joints and dolines are common.
- Deep gorges and steep-sided valleys formed where cave roofs collapse, and re-emergence of streams as springs at the foot of the limestone.
Akọwa Nkọwa
(a) Meaning of karst topography
Karst topography is the distinctive scenery that develops in regions of thick, well-jointed limestone (or other soluble rock such as dolomite or chalk) as a result of solution (carbonation) weathering. Rainwater, being a weak carbonic acid, dissolves the limestone along its joints and cracks, producing a landscape of underground drainage with characteristic surface and underground features. The name comes from the Karst region of the former Yugoslavia.
(b) Four features found in karst regions
- Swallow holes (sink holes / dolines).
- Limestone caves and caverns.
- Stalactites and stalagmites (in the caves).
- Limestone pavements with clints and grikes; also gorges and underground streams.
(c) Five characteristics of karst regions
- Underground drainage: surface streams disappear down swallow holes and flow underground, so the surface is often dry.
- Presence of caves and caverns formed by solution beneath the surface, decorated with stalactites (hanging from the roof) and stalagmites (rising from the floor).
- Bare, rocky surface with limestone pavements (clints separated by grikes) and thin, poor soils, so vegetation is scanty.
- Numerous joints and cracks in the well-bedded limestone along which solution takes place; enlarged joints and dolines are common.
- Deep gorges and steep-sided valleys formed where cave roofs collapse, and re-emergence of streams as springs at the foot of the limestone.
Ajụjụ 16 Ripọtì
(a) Explain the term settlement
(b) Describe four characteristics of an urban settlement
(c) Outline four functions which an urban settlement can perform for a rural settlement
(a) Meaning of settlement
A settlement is any place, ranging from a single homestead to a large city, where people live and build their dwellings and carry on their activities. It is the way in which people group their houses and occupy a piece of land. Settlements may be temporary or permanent, and are broadly divided into rural (village) and urban (town/city) types.
(b) Four characteristics of an urban settlement
- Large population living at high density, so houses are close together and often storeyed.
- Non-agricultural occupations dominate: most people work in industry, commerce, services and administration rather than farming.
- Well-developed infrastructure and services: good roads, electricity, pipe-borne water, schools, hospitals, banks, markets and recreational facilities.
- Complex functions and land use with distinct residential, commercial, industrial and administrative zones, and a wide range of social groups.
(c) Four functions an urban settlement performs for a rural settlement
- Market/commercial centre: the town buys the farm produce of the villages and supplies them with manufactured goods.
- Provision of services: it offers higher-order services such as hospitals, secondary and tertiary schools, banks and administrative offices used by rural people.
- Source of employment: it absorbs surplus rural labour, providing jobs in industries and services.
- Centre for processing and distribution: it processes raw materials from the countryside and acts as a transport/collecting hub linking the villages to wider markets; it also supplies farm inputs (tools, fertiliser) and spreads new ideas and technology.
Akọwa Nkọwa
(a) Meaning of settlement
A settlement is any place, ranging from a single homestead to a large city, where people live and build their dwellings and carry on their activities. It is the way in which people group their houses and occupy a piece of land. Settlements may be temporary or permanent, and are broadly divided into rural (village) and urban (town/city) types.
(b) Four characteristics of an urban settlement
- Large population living at high density, so houses are close together and often storeyed.
- Non-agricultural occupations dominate: most people work in industry, commerce, services and administration rather than farming.
- Well-developed infrastructure and services: good roads, electricity, pipe-borne water, schools, hospitals, banks, markets and recreational facilities.
- Complex functions and land use with distinct residential, commercial, industrial and administrative zones, and a wide range of social groups.
(c) Four functions an urban settlement performs for a rural settlement
- Market/commercial centre: the town buys the farm produce of the villages and supplies them with manufactured goods.
- Provision of services: it offers higher-order services such as hospitals, secondary and tertiary schools, banks and administrative offices used by rural people.
- Source of employment: it absorbs surplus rural labour, providing jobs in industries and services.
- Centre for processing and distribution: it processes raw materials from the countryside and acts as a transport/collecting hub linking the villages to wider markets; it also supplies farm inputs (tools, fertiliser) and spreads new ideas and technology.
Ajụjụ 17 Ripọtì
(a) Draw a sketch map of Nigeria. On the map, locate and name;
(i) The Eastern Railway Line;
(ii) four major stations along the railway line in (a)(i) above
(b) Outline three advantages of rail transportation in Nigeria
(c) Highlight three limitations of rail transportation in Nigeria
(a) Sketch map of Nigeria showing the Eastern Railway Line
Key: solid line = Eastern Railway Line. The four stations shown are Port Harcourt, Aba, Enugu and Makurdi.
(b) Advantages of rail transport in Nigeria
- It is a relatively cheap means of carrying bulky and heavy goods, such as cement, petroleum products, minerals and farm produce, over long distances.
- It has a high carrying capacity: a train can convey many passengers or large quantities of freight at one time.
- It links distant parts of the country, promotes trade and national integration, and opens up areas served by the railway.
(c) Limitations of rail transport in Nigeria
- Railways operate on fixed tracks and fixed schedules; they do not provide door-to-door service, so road transport is needed at both ends of a journey.
- The railway network is limited, with many old, poorly maintained tracks, locomotives and coaches, leading to breakdowns and delays.
- Construction, rehabilitation and maintenance of railway lines are very costly, especially where bridges, drainage works and difficult terrain are involved.
Akọwa Nkọwa
(a) Sketch map of Nigeria showing the Eastern Railway Line
Key: solid line = Eastern Railway Line. The four stations shown are Port Harcourt, Aba, Enugu and Makurdi.
(b) Advantages of rail transport in Nigeria
- It is a relatively cheap means of carrying bulky and heavy goods, such as cement, petroleum products, minerals and farm produce, over long distances.
- It has a high carrying capacity: a train can convey many passengers or large quantities of freight at one time.
- It links distant parts of the country, promotes trade and national integration, and opens up areas served by the railway.
(c) Limitations of rail transport in Nigeria
- Railways operate on fixed tracks and fixed schedules; they do not provide door-to-door service, so road transport is needed at both ends of a journey.
- The railway network is limited, with many old, poorly maintained tracks, locomotives and coaches, leading to breakdowns and delays.
- Construction, rehabilitation and maintenance of railway lines are very costly, especially where bridges, drainage works and difficult terrain are involved.
