312/1

GEOGRAPHY

Paper 1

JUNE 2022

Time: 2¾ hours

KASSU JET JOINT EXAMINATION

Kenya Certificate of Secondary Education

312/1

Paper 1

GEOGRAPHY

SECTION A

Answer all the questions in this section.

1. (a) State three reasons why it is important to study geography (3 marks)

It leads to development of career opportunities

Promotes positive attitudes towards protection

Encourages international awareness

Encourages time management or responsibility

Helps to develop mental skills

(b) What is the relationship between Geography and Agriculture

Geography studies the relief of an area which helps identify areas suitable for agricultural activities.

Geography studies different types of soils which influence types of agricultural crops.

Geography deals with the study of climate and weather which is important in the planning of agricultural activities such as planting and harvesting.

2. (a) What is weather forecasting? (2 marks)

It is the prediction of the state or condition of the atmosphere of a given place within a specified time.

(b) List three elements of weather. (3 marks)

Humidity

Air pressure

Rainfall

Wind

Cloud cover

Study the diagram below and use it to answer the questions (a) and (b) below.

Identify the feature (1 mark)

Plug dome/plug volcano/spine volcano

Describe how it is formed. (4 marks)

Earth movements from a vent in the Earth's crustal rocks.

Highly viscous magma is forced out through the vent as a cylindrical mass.

The eruption is explosive, breaking the rocks around the vent, and the rock debris settle around the vent.

The magma cools and solidifies rapidly as it rises, forming a plug.

More underground magma pushes upwards, rising higher above the ground to form a cylindrical circular pillar of solid lava called a plug.

(a) What is Karst scenery? (2 marks)

It is a landscape made of chalk, limestone, or dolomite rock surfaces and underground features formed due to carbonation and solution processes.

(b) State three factors influencing the occurrence of underground water.

The amount of rainfall

Slope gradient

Vegetation cover

Level of ground saturation

The rate of evaporation

The diagram below shows how land glaciated features. Study the diagram and answer the following question.

What is outwash plain (2 marks)

It is a gentle sloping area made of unconsolidated materials of clay, soil, and gravel deposited in a surface manner in lowland glaciated areas by meltwater.

Identify the features marked U, V, and W (3 marks)

U – Drumline

V – Erratic block

W – Moraine dammed lake.

SECTION B

Answer question SIX and any other TWO questions from this section.

6. Study the map of Nyeri 1:50000 (sheet 120/4) provided and answer the following questions

(a) (i) Name the two districts in the northern part of the map extract (2 marks)

Laikipia district

Nyeri district

(ii) Give the latitudinal extent of the area covered by the map (2 marks)

From 0°19' South to 0°30' South

(iii) According to the marginal information provided in the map, what is the magnetic variation of the area when the map was drawn. (2 marks)

Magnetic variation = 1° 31′

(iv) Calculate the area of Nyeri forest on the map. Give your answer in square kilometers. (2 marks)

Complete square = 2

Incomplete squares = 21

Area = 2 + 21/2 = 2 + 10.5 = 12.5 km

Describe drainage of the area covered by the map (5 marks)

The main drainage feature is rivers

River Chanya is the main river

Most rivers are permanent

There are many reservoirs in the area covered by the map

River Chanya and its tributaries form a dendritic drainage pattern

Rivers generally flow from west to east/westwards

There is a high density of/many rivers in the area covered by the map

Most rivers originate from Aberdares forest

Most rivers are bending/winding

Most rivers are in the youthful stage

(c) Citing evidence from the map, explain three factors that favour the growing of coffee in Nyeri area. (6 marks)

The area experiences cool temperatures that favour coffee growing due to high altitude as evidenced by contours that rise above 1600 metres above sea level

The area receives high rainfall that is adequate for growing coffee as evidenced by the presence of many permanent rivers/presence of forests

The area has well-drained soils suitable for coffee growing, evidenced by the presence of gently sloping terrain as indicated by moderately spaced contours

The area has an adequate supply of labour necessary for coffee picking, evidenced by the high density of settlement

The area has a well-developed transport network for transporting coffee to the coffee factories, evidenced by the many roads/tracks

(NB the factor, evidence, and explanation must be given)

(d) Explain three factors that have influenced settlement in the area covered by the map (6 marks)

Transportation: the area is served by many roads, which makes the movement of people and goods easy, thus encouraging settlement along the roads

Drainage: there are few settlements/no settlements along the rivers/near reservoirs. This may be due to seasonal flooding/presence of pests and waterborne diseases

Vegetation: there are no settlements/few settlements within the forests due to land being reserved for forests

Relief: there are many settlements in the southeastern part because the land is gently sloping/most of the river valleys have no settlement

(a)(i) Differentiate between a rock and a mineral. (2 marks)

A rock is a substance that is an aggregate of mineral particles forming the earth's crust while minerals are naturally occurring inorganic substances with definite physical and chemical properties occurring at or beneath the surface of the earth.

(b) Describe the following characteristics of minerals. (2 marks)

(ii) Hardness. (2 marks)

This is a measure of resistance of a mineral to disintegration. Some minerals e.g. diamond have a high resistance to breakage while others are soft, e.g. Talc.

(c)(i) What are igneous rocks? (2 marks)

These are rocks that are formed from cooling and solidification of magma or lava on or below the earth’s surface.

(ii) State three notable differences between plutonic and volcanic rocks. (3 marks)

Plutonic rocks form from magma while volcanic rocks form from lava.

Plutonic rocks form deep in the earth’s crust while volcanic rocks form on the surface of the earth.

During formation of plutonic rocks, magma cools slowly while during formation of volcanic rocks, lava cools rapidly.

Plutonic rocks form large crystals/coarse-grained/ textured while volcanic rocks form small crystals or no crystals at all/are fine-grained. (3 marks)

(d) Describe the formation of the following rocks.

(i) Mechanically formed sedimentary rocks. (3 marks)

Sediments of rock particles are derived from pre-existing rocks by the process of weathering.

The sediments are transported by agents of erosion e.g., water, wind, ice, and deposited in sea or on land in layers.

The sediments undergo compaction and cementation as more layers are deposited and consolidated to form a new rock.

(ii) Chemically formed sedimentary rocks. (3 marks)

They form when minerals in rocks get dissolved and carried in solution in water bodies.

Water reaction with these dissolved minerals leads to precipitation of the sediments.

The sediments accumulate at the bottom of the water body and finally compress to form a rock.

8. Identify the missing type of rocks. (3 marks)

(a) Supposing you were to carry out a field study on rocks at the Kenyan coast.

(i) State two reasons as to why you would ask for permission from the school administration. (2 marks)

For the administration to be informed of some students being out of school for official purposes.

To help in preparation of the budget needed.

To help in preparation of the transport means. (any first 2, 1=2mks)

(ii) What reasons would you give for the widespread of sedimentary rocks at the coastal plain? (3 mks)

The coastal plains were once part of the extensive continental shelf of the Indian ocean and so sedimentation took place.

Shallow continental shelf provided a conducive environment for coral polyps to form sedimentary rocks.

Many rivers deposit their load at the mouth in the ocean, accumulating to form sedimentary rocks.

10 (a) Differentiate between soil texture and soil structure (2 marks)

Soil texture is the size distribution of mineral particles composed in the soil, while soil structure is the way the individual soil particles are arranged and joined to form lumps/clusters.

OR

Soil texture is the coarseness and fineness of soil grains, while soil structure is the arrangement of soil particles to form particular shapes.

(ii) Apart from living organisms, name four other components of soil (4 marks)

Organic matter

Soil water / moisture

Soil air

Mineral particles / weathered materials / inorganic matter

(b) The diagram below shows different layers of soil. Use it to answer questions (b) (i), (ii) and (iii)

(i) Name the soil layers X, Y, and Z. (3 marks)

X – Sub soil

Y – Weathered parent rock materials

Z – Parent rock

(ii) Give two main processes of soil formation which takes place in horizon W (2 marks)

Elluviation

Leaching

(iii) State four characteristics of soil in horizon X (2 marks)

Consists mainly of silicate clays, aluminium and iron

Made up of hard pan/laterite

Soils are prismatic/columnar

It’s a zone of illuviation/zone of enrichment

Soils are generally dark in colour

Explain how the following farming practices may result to loss of soil fertility

(i) Continuous irrigation (2 marks)

Causes leaching of soil nutrients making the soil deficient of soluble minerals causing soil salinity

(ii) Over grazing (2 marks)

Leads to the removal of vegetation cover thus exposing the soils to agents of soil erosion which will remove the top fertile soils

(iii) Over cultivation (2 marks)

Weakens the soil structure making it easy for agents of soil erosion carrying away the top soil

May increase oxidation resulting to loss of organic matter

(d) Explain ways in which natural vegetation may prevent soil from erosion (4 marks)

Plant leaves cover and reduce the force of the rain drops controlling splash erosion

Vegetation cover increases the rate of rain water infiltration into the soil reducing surface run off controlling sheet erosion

The roots of plants increase the rate of rain water percolating into the soil controlling erosion

The plant roots bind the soil particles together thus controlling erosion

Plant cover reduces the rate of soil water evaporation making the soil moist/wet and compact

Dead and decaying vegetation matter adds humus to the soil making the soil particles bound