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TOPIC 1: SKILLS
A. Locating Features Using Grid References

4-figure grid references:
for general purposes
07
06
A
Northings
next (‘Up
the stairs’)
05
E.g.:
 A is located at grid 7005
04
70
71
72
73
Eastings first
(‘Along the floor’)

6-figure grid references:

P
07
5
for a more precise location
06
E.g.:
 Actual location of P is located at
grid reference 714065
2. Northings
(‘Up the
stairs’)
05
71
4
1. Eastings
(‘Along the floor’)
72
B. Finding Directions


Directions on a topographical map are given with reference to grid north.
Two ways to find directions:
I. Compass points
 Main or cardinal points: North, South, East and West. These are the general
directions.
 4 subcardinal points: NE, SE, NW and SW. They are found between the
cardinal points, which enable us to state the directions more accurately.
 8 subsidiary points: NNE, ENE, ESE, SSE, SSW, WSW, WNW and SSW.
They are found between the 4 subcardinal points, to allow for even greater
precision.
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II. Angular bearings
 Bearings are compass directions measured in degrees clockwise from 0°, east
is 90°, south is 180° and west is 270°.
 The bearings on topo maps are always measured from grid north and so they
are called grid bearings.
Cardinal, subcardinal, and subsidiary points
Compass bearings
Reading Compass Direction and Grid Bearing
Example I:
Two places are marked on the map (X and Y).
To find the angular bearing of Y from X:
1. Join the two points X-Y by a straight line.
2. Draw a straight line from North to South through
point X.
3. Measure clockwise the angle between the two
points X and Y.
4. The angle is 120°.
5. The direction of Y from X is East South East
(ESE).
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Example II:
1. To find the angular point of Q from P:
(follow the steps shown above)
2. The angle is [180° (North to South) + 70°] =
250°.
3. The direction of Q from P is West South
West (WSW).
C. Measuring Distances
 A scale is the ratio between the distance on the map and the actual distance on
the ground of two points.
 Map scale can be shown in 3 ways:
 Statement scale (written in words or figures)
E.g. 1cm represents 1km
 Line / Linear scale (a line that is divided into units and fractions of unit)
E.g.
 Representative fraction (R.F.) or representative scale (written in the form of ratio)
E.g. 1: 50 000
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Using R.F. To Calculate Actual Distance on the Ground
Example:
What is the actual distance on the ground in km between two
features that are 7cm apart in a map, given R.F. is 1:20 000?
Answer:
1 cm on the map represents 25 000cm (or 0.25km) on the ground
Therefore, 7cm on the map = 7 x 0.25km
= 1.65km
 There are two types of distance on topo maps, and are measured differently.
(a) Straight line distance:
(i) Use a ruler.
(ii) Measure the distance from one point to the other.
 The distance measured on the map and then read off the given graphic or
linear scale.
(b) Curved distances:
(i) Use a piece of thread/ a strip of paper.
(ii) Divide the length of the feature you are going to measure (e.g. Points A-B of
the river) into several short straight sections (#1 – #5).
#3
A
#1
#4
B
#2
#5
(iii) Lay the straight edge of a strip of paper along the line distance from the first
section (#1) to the second and third section (#2 & #3).
Mark the distance on the paper.
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#3
#2
1
#1
(iv) Begin from #3. Lay the straight edge of the paper to #4.
Mark the distance on the paper.
#1
#2
#3
#4
(v) Using the same method, mark the distance from #4 to #5.
#1
#2
#3
#4
#5
(vi) Measure the total distance for all sections (#1 to #5) by placing your paper
against the linear scale to obtain the correct actual distance, as shown below.
The distance from #1 - #5 along the river is 3km or 3000m.
#1
#2
#3
#4
#5
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Example:
1:50 000
1. Measure the direct (straight-line) distance (in km) from the School to the Post
Office (PO).
Answer:
Scale on the map: 1:50000 or 1cm represents 0.5km
Straight line distance on map: 4.7cm
Direct straight line distance = 4.7cm x 0.5km
= 2.35km
2. Measure the actual distance (by road) from the School to the Post Office.
Answer:
Scale on the map: 1:50 000 or 1cm represents 0.5km
Distance on map: Approximately 5.1cm
Actual distance (along the road) = 5.1cm x 0.5km
= 2.55km
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D. Interpreting Relief and Drainage
Contour lines
 A contour line is a line on a map, which joins all points of the same height above sea
level.
 They are printed in metres; and they show the relief accurately.

When the contour lines are spaced far apart the land is gentle.

When the contour lines are very close together the land is very steep.

When there are no contour lines, the area is flat.
I. A contour map
A contour map has the following features:
(a) contour lines to represent relief features
(b) height shown in units of metres or feet
(c) a contour interval / vertical interval (V.I.) between two contour lines
 contour intervals are small where relief is low
(e.g. lowland areas : 5 or 10m)
 contour intervals are large in mountainous regions (e.g. 100m, 150m
or more)
E.g. The contour interval in the map above is 100m
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II. Relief features as shown on the contour map
1. A Valley
A
long
and
narrow
depression
between
two
areas
highland
that
of
usually
carries
a
river/stream.
 Identified
from
V-shape
pointing to highland.
2. A Spur
 An area of highland that
projects (juts) out from the
side of a mountain/hill.
 Identified
from
V-shape
pointing to lowland.
3. A Hill
 Represented
by
circular
contour lines.
4. A Knoll
 A small rounded hill situated
away
from
the
other
highland or mountain range.
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5. A Plateau
 A flat topped upland.
6. Undulating ground
 A flat topped upland.
6. A Saddle / Col
 A low point on a ridge or a
line of mountains.
 It is sometimes called a col.
6. Ridge
 A long narrow upland or a
linear steep-sided upland,
forming the highest part of a
range of mountains.
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7. An upland region with gap, pass and
peaks
 Gap - A lowland valley which cuts
across a ridge
 A river may flow through the gap
 Pass - A narrow passage or gap
across a range of mountains; similar
to a saddle but is deeper
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Relief Features: Slopes
 Contour Patterns
 Steep Slope
 represented
 Gentle Slope
by
contours
close
 represented by contours wide apart
together
Steep & gentle slopes
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 Uniform Slope
 Stepped Slope
 the spaces between the contours
 represented by contours in turn steep
remain the same (from top to foot)
and gentle at intervals.
 wide contour spacing alternates
with narrow contour spacing
Uniform & irregular (stepped) slopes
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 Concave Slope
 Convex Slope
 the spaces between the contours  the spaces between the contours
decrease as height increases.
 gradient
becomes
gentler towards the foot
increase as height increases.
progressively  gradient
becomes
progressively
steeper towards the foot
Concave & convex slopes
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Relief Features: Rivers
1. Gorge
 A deep and narrow valley with precipitous
rocky walls, generally occupied by a river.
2. Bluff
 A high bald headland or a steep prominent
cliff on the outer bank of a meandering river.
 The
erosive
force
of
water
is
partly
responsible for the steepness of the wall.
3. Interlocking spurs
 Spurs on the opposite sides of a valley
interlock to form interlocking spurs.
 Due to the position of the spurs, the river
flows through bends at every turn.
Relief Features: Coasts
1. Headland
 A coastal feature which resembles a cape.
 It projects seaward with a steep slope
merging with the seawater.
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III. River Drainage Patterns
-
Refers to the arrangement of the river and its tributaries in a drainage basin.
1. Dendritic (tree-like)
 River has many tributaries joining from many
directions to main river at acute angles (less than
90°);
 A shape like the trunk and branches of a tree.
 The most common river drainage pattern.
2. Radial (spoke-like)
 River flows down in all directions from the top of a
hill/mountain;
 Resembles the spokes of a fully opened umbrella.
3. Trellis (rectangular)
 The tributaries join the river at almost right angles
(90°);
 Streams flow over a region with resistant and lessresistant rocks alternating in structure.
 Resembles the pattern formed by bricks on the
wall.
4. Centripetal
 Stream or tributaries down to a central point;
 Opposite to the radial pattern.
 Common in inland basins and desert regions
where streams from various directions drain
towards a central depression.
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The Interpretation of Topographical Maps (Human Aspects)
3 major aspects of topographical landscape:

Land use

Transport

Settlements
Land-use features
1. Be familiar with all the symbols used to denote various kinds of land use
Example:
 Agricultural land use
- usually are green in colour
 Roads
- major roads: usually shown in red (
)
- minor roads & tracks: usually in yellow
 Railways
 Rivers & streams
- black and white pecked lines (
)
- light blue in colour
2. Land use is always related to physical landforms
Example:
 Low lying areas
- suitable for food crop cultivation such as padi & fruit
 Undulating grounds
- most suited to grow cash crops (rubber, oil palm),
where drainage is better
 Hilly areas
- can support certain crops like rubber; & padi can be
grown on terraced hills
 Mountainous regions
- terraced highland areas are suitable for growing tea &
cultivated vegetables (e.g. Cameron Highlands)
 Limestone hills
- would not support crops but are quarried for marble,
road constructions and cement works
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A. Agricultural land use
1. Padi cultivation
 Padi fields are located mainly in level, low-lying areas, which can be easily flooded.

T
hus, most widely found in river valleys, flood plains, deltaic regions & coastal plains where
there are no contours or at most at 15m contour.
 Also cultivated in land reclaimed from swamps along rivers & seacoast.
 Most padi farms are criss-crossed with network of drains and canals; allow for irrigation.
 Hill padi is also grown on higher ground, often in terraced slopes, usually above 100m.
 Roads are extensively used to bring in fertilizers, insecticides and machinery to padigrowing areas and to transport padi to nearest rice mills.
2. Rubber cultivation
 Rubber is widely grown on undulating land as there is excellent drainage.
 Rubber can also be cultivated between 50m to 200m on hill slopes, but not beyond
600m because it is too cold for the trees to survive. The latex does not flow readily.
 Rubber can also be grown on reclaimed swampland along rivers & sea coast,
provided it does not flood.
Large rubber estates need well-developed network of main roads and secondary
roads as the tapped latex has to be sent to the factories for daily processing. There are
also clusters of labour lines, large bungalows for the estate manager, and a Hindu temple
for the tapper as many of them are Indians in Malaysia.
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 Secondary roads and footpath serve rubber small-holders as they cannot afford the
construction of good roads and modern houses.
 Railways are less important than roads, but where the railway line runs close to an estate,
it serves to transport processed rubber of export through the nearest port.
3. Oil palm cultivation
 Oil palm is a fast-expanding cash crop and is now the most extensively cultivated in both
estates and small-holdings.
Oil palm is grown in extensive land, in low-lying areas where the soil is peaty.
 A system of light railways and roads (for lorries) are built within the plantation to provide
speedy transport of the harvested fruit to the palm oil mills. (Any delay in transportation will
result in the loss of its fat content and the quality of the processed oil).
 The road or railway system also connects the big estate to the main settlement where
the factory, labourers’ quarters, the office and other services are found.
A good network of roads is also built to bring the processed palm oil to the nearest ports
for export. Oil palm estates can be very big and a labourer may take several hours to walk
from one part of the estate to another. Therefore, an efficient transport system is
needed to convey the labourers to all part of the estate and to collect the produce and take
it to the factory.
On these estates, the settlements are mostly clustered together in the central area for
quick and easy gatherings and meetings.
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4. Coconut cultivation
 Coconuts are mainly grown in low-lying areas, flat ground and the sandy coastal regions
where the drainage is good.
 The coconut small-holders are served mainly by minor roads or rivers to transport their
coconuts, copra or coconut oil.
5. Tea
 It is mainly confined to cooler upland regions (on hill slopes – indicated by contours)
such as Cameron Highlands in P. Malaysia, in large tea plantations.
6. Sugar cane
 Sugar-cane is grown extensively in large plantations on lowlands as well as on
undulating inland regions. It is served by railways & roads to be transported to the
nearest mills for processing into refined sugar.
Tea and sugar cane plantation
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7. Local fruits and vegetables
 These are grown by farmers in the outskirts of towns for the local market. Fruits like
mangoes, pomelo and papaya are grown in small orchards.
 All kinds of vegetables are grown by local farmers in small market farms for the daily
needs of the people. Market gardens are served by roads to the nearest market.
 The more valuable highland vegetables (e.g. cabbage & lettuce) are grown by farmers
on terraced hill slopes in the cool Cameron Highlands.
8. Cocoa
 It is ether grown in small holdings on lowlands.
 It is a lowland crops and provide some cash income before the rubber trees are matured
enough to be tapped for their latex.
B. Mining land use
1. Open cast mining
 Evident with symbol: (
), as mining holes are often left behind after the mineral (e.g.
tin or coal) has been extracted.
 Roads are seen leading to the mines as lorries are used to transport the lodes or ores
from the bottom of the mines to the processing centres. There might also be paths used
by jeeps and workers in approaching the mining area.
Tin-mining region
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C. Transport
1. Transport or communication is important for the development of agriculture, mining,
industries, trade and settlement growth.
2. Pattern of road system:
(i) Dispersed pattern
(ii) Concentric pattern
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(iii) Grid-iron pattern
- They are rectangular in pattern.
- E.g.: Estates are served by better roads, and a higher density of transport
network.
- This type of pattern is also found in New Towns and planned administrative
capitals (e.g. Canberra in Australia).
3. How various physical factors affect the pattern & density of the transport network:
(i) Physical relief
- Roads and railways avoid steep hills because vehicles and trains cannot move or pull
load over very steep gradient.
- Many roads in alpine areas go in a zig-zag pattern to overcome steep gradients.
- Where there are alternatives, roads and railways will be built through gaps and pass
so as to avoid the hills to save cost and construction effort.
(ii) Floods & swamps
- Where a lowland area is liable to floods, roads and railways are built on levees and
embankments to minimize flooding liability.
- Along coastal districts, roads are built away from the swamps or along higher ground
inland to avoid possible floods.
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(iii) Other specific obstacles
I. Streams & rivers
- Wooden or concrete bridges are built across them so that the traffic is not
interrupted.
II. Large lakes or inland areas
- Ferries are recommended to link two sides of a huge lake, instead of a bridge
which is expensive to build.
III. Deep valley & gorges
- Special steel bridges or embankments are raised at suitable levels to bridge such
gaps to smoothen the on-flow traffic.
IV. Obstruction by other lines of transport
- Where a road is blocked by a railway track, level crossings are used such that
cars and passengers can only cross ager the railway carriage has passed.
V. Settlements & land use
- The larger the settlement, the greater the land use, a greater density of transport
network is needed to serve the people and their economic activities.
- Different types of network used in different stages of development of a settlement
or economic activity.
Example:
 Villages are served by secondary roads, footpaths or motorable tracks.
 Large cities are served by multiple-track railway lines, all-weather metalled
roads, and even underground railways.
 Estates are served by better roads and a higher density of transport network.
 The road systems in older towns are often chaotic and unplanned. In New
towns and planned administrative capitals (e.g. Canberra, Australia) the roads
are well-laid out in a grid-iron pattern or have rectangular/concentric patterns.
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D. Settlements
1. In topo maps, a house is shown by a square or a circular dot.
2. Types of Rural Settlements:
(a) Dispersed / scattered
- There are 15 houses scattered within the map area of the rural district.
- People live far away from each other, houses are scattered.
- The diagram shows a dispersed settlement.
- E.g. In Africa: the natives live in huts far apart from one another and are served
only by a passing main road some distance away.
(b) Linear
- Houses are arranged in a line, either along a road, rail, river or canal.
- The diagram shows a linear settlement.
- Linear settlements are most commonly found in raised ground near the seacoast
or on levees along rivers. This is to avoid flooding.
- E.g. In many padi-growing areas, all the houses are found on both sides of the
canal that run parallel to one another.
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(c) Nucleated
-
The houses are grouped closely together at the junction of roads.
-
The diagram shows a nucleated settlement.
-
Settlements in estates (e.g. oil palm plantation), where the labour lives, the
manager’s house and the oil palm factory are grouped together.
-
E.g. In Malaysia: all the new villages are nucleated settlements where everybody
lives within the village boundary, complete with market, shops and community hall
in Kampung Ampang, Peninsular Malaysia.
3. In rural areas, where there are very few houses, one can count the number of houses
in a village.
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