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1Mind Maps

OSWAAL ICSE Combined Sample Question Papers for Semester-I, GEOGRAPHY, Class-X2

3Mind Maps

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7Mind Maps

ON TIPS NOTES

CHAPTER 1: Interpretation of Topographical Maps

Key Points and Concepts Topographical maps are the comprehensive and detailed description of cultural and natural features on

earth. One of the important features of the topographical map is grid reference. The grid reference is a set of horizontal and vertical lines, like latitude and longitude, to find the location

of a place on a map. A place’s position is fixed by noting its distance East and North of the origin of the grid. These are

known as Northing and Easting. Location can be calculated with the help of four-figure grid reference. For making the map interpretation easy, conventional signs and symbols are used on topographical

maps. These are used on a map to get detailed information about natural and cultural features. Topographical maps of India are prepared by the Survey of India. It includes India and its adjacent

countries. Topographical maps are the maps with detailed and accurate graphical representation of natural and

cultural features on the ground. Information is provided on a topographical map through the use of contour lines, scale, grid reference,

colour and symbols. All the elevations in topographical sheets can be shown with the help of contours. Contours are the imaginary lines drawn on the map to join the same elevations. Contour interpretation is done by relating the contour features on the map with real features on the

ground.l These features are contour interval, index contours, datum level, vertical interval, horizontal equiv-

alent, spot heights, triangulation points and benchmarks. The direction of a place is expressed in relation to a given point. The four directions are East, West, North, and South. North refers to the direction followed to get to the North Pole. True North is a geographical direction represented on maps and globes by lines of longitude. It is

indicated by the pole star. Magnetic North is the point at the top of earth that determines compass headings. Grid north is the direction of a grid line, which is parallel to the central meridian on the map. A bearing is the clockwise measurement of the angle formed between the north line and the line joining

the two given points.

Note making is a skill that we use in many walks of life : at school, university and in the world of work. However, accurate note making requires a thorough understanding of concepts. We, at Oswaal, have tried to encapsulate all the chapters from the given syllabus into the following ON TIPS NOTES. These notes will not only facilitate better understanding of concepts, but will also ensure that each and every concept is taken up and every chapter is covered in totality. So go ahead and use these to your advantage… go get the OSWAAL ADVANTAGE!!

9On Tips Notes

Globe is the actual representation of the earth. It is the drawing on a sphere representing the true shape of the earth. There are certain disadvantages of the globe, which makes the study of maps very important in geography.

The map is a symbolic representation of the earth or a part of it drawn on a flat surface. The elements of the map are the title, key or legend, direction, scale and grid system. Map projection is the process of transforming earth’s spherical surface to a flat map while maintaining

its spatial relationships. Maps can be classified on the basis of scale and on the basis of content. On the basis of the scale, map can be classified into large scale and small scale. On the basis of content, maps can be classified as political, physical and thematic. Gradient refers to the slope of the land. It is defined as the ratio of the change in height with distance. The land gradient is equal to vertical interval divided by horizontal equivalent. There are different types of slopes.

l Gentle Slope: When the contour lines are spaced further apart from each other.l Steep Slope: When the contour lines are drawn closer to each other.

Scale is an essential element in all types of maps. A scale is the ratio between a distance measured on a map and the corresponding distance on the

earth’s surface. Three types of scales are used:

l Statement of Scale, the scale of a map is indicated in the form of a written statement.l Graphical or Bar Scale shows map distances and the corresponding ground distances using a line

bar. It is divided into primary and secondary divisions. It is 10 to 20 centimeters long which is divided into 8 divisions of two cm each representing one km each from 1 to 7 km.

l Representative Fraction (R.F.) shows the scale of a map as a fraction or ratio. The numerator denotes the length on the map and the denominator denotes the actual distance on the ground. e.g. 1:50,000.

Map scales can be converted from one to another according to the user’s need. Theheightthatisrepresentedbyatriangle(Δ)besideanumberwhichindicatesitsheightabovemean

sea level, likeΔ234 iscalledTriangulatedHeight. It ismoreaccurate thanSpotHeightbecause it iscalculated by trigonometry.

Spot Height is represented on the map by a black dot in front of the number like, .176, which indicates the height of that particular point above mean sea level.

Surveyors make a permanent cut or mark on a rock, stone, prominent building or place called the Bench Mark (B.M.). It indicates the height of that place above mean sea level.

CHAPTER 2: Location, Extent and Physical Features

Key Points and Concepts India isaSouthAsiancountry locatedbetween8°4′Nand37°6′ N latitudes, while the longitudinal

extent of the country is 68°7′ E and 97°25′ E longitudes. Thestandardmeridianofthecountrypassesthrough82°30′ E longitude. India has a total land boundary of 15,200 km and a coastline extending upto 7,516.6 km that includes the

coastline of Andaman and Nicobar Islands. It is connected to Asian and European countries through land and sea routes, respectively. India shares its land boundaries with Pakistan, Afghanistan, China, Nepal, Bhutan, Bangladesh and

Myanmar. Sri Lanka is separated from India by a narrow canal of sea formed by Palk Strait and the Gulf of Mannar,

whereas the Maldives Islands are situated to the south of Lakshadweep.


The Indian sub-continent island has been divided into five physiographic divisions : l The Northern Mountain Walll The Plains of Northern Indial The Peninsular Plateaul The Coastal Plainsl The Islands

The Himalayas is broadly divided into:l The Western Himalayasl The Eastern Himalayas

The longitudinal divisions of the Himalayas are:l Himadri,l Himachal andl Shivalik

The Indus-Ganga-Brahmaputra Plain

The main relief features of the Northern Plains are:l Bhabar l Terai l Bhangar l Khadar

The Peninsular Plateau

It is made up of hard, crystalline, igneous and metamorphic rocks. The plateau is triangular in shape. The average elevation of the plateau in the South is 1000 m and in the North, it is 100 m.

The Narmada River divides the plateau into two parts: l The Malwa Plateaul The Deccan Plateaul The Coastal Plains

The extent of the Western Ghats is from the mouth of the Tapi River in the north to Kanyakumari in the south.

The average height of the Western Ghats is around 1200 metres. The highest peak of the Western Ghats is Anamudi with an elevation of 2,695 metres. The Western Ghats rise abruptly from the narrow Western coastal plains. The main sub-divisions of the Western coastal plains are:

l Konkan Coast in Maharashtral Kanara Coast in Karnataka andl Malabar Coast in Kerala

It is continuous with a steep slope and rugged topography. It is the source of rivers of the Deccan Plateau. The extent of the Eastern Ghats is from Mahanadi Valley in the north to Nilgiri Hills in the south. TheaverageheightoftheEasternGhatsis450metres. The length of the Eastern Ghats is 1100 kms. The highest peak of the Eastern Ghats is Mahendragiri with an elevation of 1500 metres. The Eastern Ghats are broken and cut through by many rivers. It rises gently from the Eastern Coastal Plains.

11On Tips Notes

The Island Groups

The two island groups of India are Lakshadweep and Andaman and Nicobar Islands. The name ‘Lakshadweep’ means a ‘hundred thousand islands’ in Malayalam and Sanskrit. These islands are of coral origin, which developed around volcanic peaks. Andaman and Nicobar Islands are the peaks of a submerged mountain range. ThehighestelevationintheAndamanandNicobarIslandsistheSaddlePeak,whichis737mhigh. Barren Island in the Andaman group is the only active volcano in South Asia.

CHAPTER 3: Climate

Key Points and Concepts The word ‘monsoon’ is derived from the Arabic word ‘mausim’, meaning season. Therefore, ‘monsoon’ can be defined as the seasonal reversal of the planetary wind system. There are a number of factors which influence the climate of India- the Himalayas, the monsoon winds,

latitude, altitude, distance from the sea, western disturbances, etc.l The Himalayas prevent the South-West moisture laden winds from crossing over it which results in

heavy rainfall in the entire Indian Sub-Continent. It also protects from the cold Siberian winds from entering the Indian region.

l The monsoon winds bring summer rainfall over the whole of South Asia. The southwest monsoon winds move from the Arabian Sea branch and the Bay of Bengal branch to the low-pressure areas of north and northwest India.

l These winds bring heavy rainfall during summers from June to September. In October when it withdraws and retreats, it picks up moisture from the Bay of Bengal and shed a good amount of rainfall on the eastern coastal plain of India. The winds blowing over the land are cold and dry.

l The important line of latitude, the Tropic of Cancer passes through the middle of India dividing it into two zones- Temperate Zone (Northern part) and the Tropical Zone (Southern part). The southern tropical zone remains warm throughout the year and practically has no winter season.

l The places beyond the Tropic of Cancer never experience overhead sun while all the places in the southern zone experience overhead sun twice a day.

l Relief is also an important factor in affecting the climate of India. The Western Ghats stand as a barrier on the way of the South-West monsoon winds which come from the Arabian Sea and result in heavy rain on the western coastal plains.

l The Himalayas in the extreme north prevents the moisture laden winds from crossing it and thus, causes heavy rainfall in the major portion of the Indian Sub-Continent. The Aravalli Range in the west runs parallel to the South West monsoon winds and thus, doesn’t shed any rainfall in that region.

l Higher the altitude, lower the temperature. It is due to normal Lapse Rate, i.e. for every rise of 166 metres, there is a decrease of 1°C of temperature. Thus, the mountains are cooler than the plains.

l The three major surrounding water bodies. The Indian Ocean, Arabian Sea and Bay of Bengal have a great influence and impact on the water bodies. They are the major source of rain in India and also due to its proximity; the coastal places have moderate climatic conditions.

l During the winter season, due to the Western disturbances over the Mediterranean Sea, the westerly cyclonic winds blow towards India and bring the northwest part of India under its influence. These cyclonic winds bring rain to the North West part of India.

l Air currents which determine the arrival and departure of the monsoons are known as Jet Streams. The westerly jet streams prevail over the northern plains while the easterly jet streams steer the tropical depression over India.

l Due to the distance from the sea, the areas far away from the influence of the sea experience


continental type of climate, i.e. too hot in summers and too cold in winters. The coastal places, on the other hand, experience equable or maritime climate due to the nearness of the sea. The land breeze and sea breeze are caused due to the differential heating and cooling of land and sea.

l El-Nino is a warm ocean current which increases the surface temperature of the sea and affects the monsoon winds in the Indian Ocean. It causes a weak drought-like situation in the Indian Sub-Continent.

In India, on the basis of monsoon variations, the year may be categorized into four main seasons. They are:

l The Hot Summer Season (March to May) l The Hot and Wet or Rainy Season (June to September) l The Retreating South West Monsoon (October to November) l The Cold and Dry Winter Season (December to February) Features of the Indian monsoon are:

l Monsoon rainfall occurs in summer.l Rainfall is unpredictable.l Indian monsoon is also characterized by orographic rainfall.l Rainfall is unevenly distributed.l Indian monsoon has convectional rainfall.l Rainfall also affects the economy of the country. l The Arabian Sea branch of monsoon causes more than 200 cm of rainfall in the Western Ghats.l Rainfall decreases from west to east and from south to north.

The Bay of Bengal branch strikes the coast of Myanmar and part of south-east Bangladesh. Arakan Hills along the coast of Myanmar deflect a big portion of this branch towards the Indian Sub-

continent. Monsoon enters West Bengal and Bangladesh from south and south-east and not from the south-

westerly direction. In the month of October, the South –West Monsoon winds weaken and start withdrawing. The temperature and humidity levels are still high and this period of oppressive heat and humidity is

called October Heat. Similarly, Kalbaisakhi is a local wind that blows in West Bengal and Assam in the month of April, which

is accompanied by thunderstorms and heavy rainfall. This rain is beneficial for the growth of tea in Assam and rice and jute in West Bengal. Mango Showers or Cherry Blossoms are also the local winds which blow in Kerala during summers in

June. This wind helps in the growth of mango, coffee and tea. By the end of September, monsoon winds retreat up to Punjab from Central India by mid-October and

from the southern coast of India by early November. The Bay of Bengal branch carries with it cyclones from the Andaman Islands and strike India’s Godavari

Krishna basin, bringing heavy rainfall in Odisha and Andhra Pradesh. The Arabian Sea branch also weakens by this time. The retreating monsoon is associated with:

l The occurrence of cyclonic depressions that originate over the Andaman Sea.l These cyclonic depressions generally cross the eastern coast of India and cause heavy and wide-

spread rainfall.l These tropical cyclones are very destructive, cause cyclonic storms in the Krishna Godavari delta.l These tropical cyclones strike the coast of Odisha, West Bengal and Bangladesh.l Huge rainfall in the Coromandel Coast during this time is caused by depressions and cyclone.

The period from December to May covers two distinct seasons. The first is the cold wet season of the north east monsoon and the second is the hot and dry season. During the cold wet season, there is high pressure over the continent, so the northeast trade winds blow from the continent to the ocean.

13On Tips Notes

These winds are known as the Northeast Monsoon. It is the time of very pleasant season with low temperature. Temperature decreases from north to south.

The hot and dry season begins in March and ends in May. During this season, the winds move from sea to the land, as there is low pressure on the land due to high temperature. This season is mostly characterized by dry atmospheric conditions with occasional local storms.

CHAPTER 4: Soil Resources

Key Points and Concepts The soil is the most productive and renewable layer of the earth. It is the naturally occurring, unconsolidated covering of broken rock particles and decaying organic

matter on the surface of the earth. The soil is formed over millions of years. Various agents of weathering and gradation produce a thin layer of soil. It is a thin layer of the crust of the earth, which serves as a natural medium for the growth of plants and

supports different types of living organisms. Almost all the ancient civilizations had developed rich fertile soils of river valleys. Despite technological advancement and industrialization, most of the world’s population still lives in

areas of rich fertile soil which helps grow food. Main factors affecting soil formation are climate, nature of parent rocks and topography. Climate is responsible for weathering, growth, and decay of vegetations and biochemical processes. Weathering is caused due to extremities of temperature, freezing and thawing of ice rocks. Vegetation determines the humus content of the soil. The roots of the plants penetrate into the soil and make the soil porous. Deep-rooted plants bring solution up from the sub-soil. Bacteria and Fungi transform the atmospheric nitrogen into soil nitrogen. Nature of parent rock determines the colour, texture, permeability, chemical and physical properties. In hills and slopes, steep slopes have a thin layer of soil. On the basis of the genesis, colour, composition and location, the soils of India have been classified into

eight types :l Alluvial soils are depositional soil as they are transported and deposited by rivers and streams. It

is the most fertile soil. l Black soil is referred to as regur soil, but is popularly known as “black cotton soil”, as the most

common crop grown on this soil is cotton.l Red soil develops a reddish colour due to a wide diffusion of iron in the crystalline and metamorphic

rocks. It looks yellow when occurs in a hydrated form.l Laterite soil is derived from the Latin word ‘Later’ which means ‘brick’. Laterite soils develop in the

areas with high temperature and high rainfall. These are found in Karnataka, Kerala, Tamil Nadu, Madhya Pradesh and the hilly areas of Odisha and Assam.

l Arid or desert soils range from red to brown in colour. These soils are sandy in texture and saline in character.

l Mountainous soils are formed in the forest areas, where sufficient rainfall is available. These soils are loamy and silty on the valley side and coarse-grained in the upper slopes.

Erosion by water occurs in regions of heavy rainfall and steep slopes. Different types of erosion caused by water are:l Sheet erosionl Gully erosionl Stream-bank erosion


Soil erosion takes place when the soil is removed faster than it is formed. Causes of soil erosion are:

l Topographyl Nature of rainfalll Increasing populationl Erratic nature of rainfalll Overgrazing by domestic animalsl Bad farming techniquesl The topography of the regionl Deforestationl Nature of soill Human factor

Soil conservation is an effort by human beings to prevent soil erosion or at least reduce the rate of erosion. Different measures for the conservation of soil are:

l Afforestationl Restricted grazingl Proper farming techniquesl Plugging of gulliesl Planting of shelter belts

Proper farming techniques need to be adopted for soil conservation. These techniques include:l Terracing of hilll Constructing bundsl Strip croppingl Contour ploughingl Planting trees

In India, the government has taken special conservation measures :l Scheme of integrated watershed managementl Rainwater harvestingl Scheme for reclamation and development of ravine areasl Scheme for control of shifting cultivationl National project on development and use of bio-fertilizers.

CHAPTER 5: Natural Vegetation

Key Points and Concepts Forests are one of the most significant features of the land surface. They are essential for the survival of animals and human beings on earth. Forests provide a number of resources to mankind. There is a continuous decline of forests due to their overexploiting by human beings. Deforestation increases the concentration of carbon dioxide in the atmosphere. It leads to global warming, an increase in temperature of the earth’s surface and atmosphere. Cutting of trees has many other harmful consequences. The conservation measures, which are required to stop the destruction of forests, are as follows :

l Increase area under forestsl Stop deforestationl Create corridors between reserved forestsl Develop alternative sources of energy

15On Tips Notes

l Strong legislation and implementation rulesl Increase people’s participation

Massive programmes for tree plantation are to be undertaken. Planting trees should be encouraged on lands unfit for agriculture. Some non-conventional sources of energy that can be used are :

l Solar Energyl Wind Energyl Hydel Energy

National Forest Policy was adopted by the Government of India in 1952. It was further modified in 1988.

The prime objectives of National Forest Policy are as follows :l Aims at maintenance of environmental stabilityl Ecological balance should be preserved.l If the ecological balance is disturbed, it should be restored.l Soil erosion and denudation in the catchment areas of rivers, lakes, etc. should be checked.l Soil and water conservation techniques should be applied for the mitigation of floods and droughts.

Social Forestry refers to the management and protection of forests. Another purpose of social forestry is afforestation of lands, which are not fit for agriculture. The main features of social forestry are :

l Raising plantations with the help of local peoplel Making proper use of unused and fallow landsl Making use of easily implement able technology

Benefits derived to be equally distributed among all the people. Agroforestry is a part of social forestry. It represents the intermediate stage between forestry and agri-

culture. Following are the objectives of social forestry:

l To reduce the pressure on natural forests for timber and non-timber producel To maintain the natural fertility of the soill To check soil erosionl To properly utilise the farm resourcesl To maintain the ecological balancel To obtain different types of forest and agricultural products sustain ablyl To make the best use of all the available resources

Tropical Rainforests are found in those areas, which receive more than 200 cm of annual rainfall. In India, they are found in the Western Ghats, Lakshadweep, Andaman and Nicobar Islands, upper parts of Assam and in the Tamil Nadu coast.

Tropical Deciduous Forests are found in areas which receive rainfall between 70 - 200 cms. They are also known as the ‘Monsoon Forests’ and are found in Jharkhand, West Odisha, Chhattisgarh and on the eastern slopes of the Western Ghats. The trees in these forests shed their leaves for six to eight weeks in dry summers.

Tropical Desert Forests are found in areas receiving an annual rainfall of less than 50 cm. These forests are found in the semi-arid areas of Gujarat, Rajasthan, Madhya Pradesh and Chhattisgarh.

The trees in these forests have long roots, which penetrate deep into the soil. They store water in their stems and have thick and small leaves to reduce the rate of transpiration. Mangrove Forests are found in the coastal regions, influenced by tides. Mud and silt get accumulated

on such coasts. The trees in these forests have their roots submerged in water. They are found in the deltas of Ganga, Mahanadi, Krishna, Godavari and Kaveri.

Mountain Forests are found in high altitude areas in the North and South. They are mostly coniferous trees.


Chapter 6: Water Resources

Key Points and Concepts Waterisaninfinitelyrenewableresource.About97%ofthetotalwaterisfoundinoceans.Only3%of

the water available is fresh water, which is found in a river, lake, stream, etc. Water is an important natural resource, which is necessary for human survival. It is used in our day-to-day life for various purposes from domestic to industrial, from agriculture to

generating electricity. Demand for water has risen due to an increase in the population. Conservation of water is needed due to declining availability and increasing demand for fresh water. Water management is the only way to boost the quality and quantity of water resources. Different methods of water conservation are :

l Construction of Damsl Harvesting Rainwater l Watershed Managementl Mass Awarenessl Recharging of Groundwater

Irrigation facilities increase the food production. As an agro-based country, it’s important to develop irrigation facilities in India. It becomes even more relevant in the wake of the fact that rainfall in India is unreliable. Favourable conditions for the development of irrigation in India are : l Perennial Rivers –Most of the north Indian rivers are snow fed and perennial.

l Excess water from these rivers can be diverted to the fields through canals.l The mountainous, rocky and uneven terrain of the north and Peninsular India provide good sites

for building dams. l Suitable sites for constructing tanks are the uneven terrain which provide natural depressions to

built tanks. l This water can be utilized for irrigation.

The first one is well irrigation. In this type of irrigation, a hole is dug in the ground to obtain the subsoil water.

There are also various methods of drawing water from well like; bucket system, Dekhli method and Rhote method.

The second means of irrigation is canal irrigation. It is carried out by building weirs or dams across the rivers. The water is stored in reservoirs and then

distributed to the fields through a network of canals and distributaries. Canals are of two types : peren-nial canals and inundation canals.

The third method of irrigation is tank irrigation. Tanks are small-sized reservoirs formed by small earthen embankment to store runoff water for

irrigation. They are usually constructed on the rocky bed to prevent seepage. Rain-water harvesting is an activity of collecting rainwater directly or recharging it into the ground to

improve groundwater storage. It is economical and environment friendly. Methods of Rainwater Harvesting There are two main techniques of rain-water harvesting :

l Traditional technique: Storage of rain-water on the surface is a traditional technique. The structures used for water storage are underground tanks, ponds, check dams, weirs, etc.

l Modern technique: It is a new concept of water harvesting and the structures generally used are pits, trench, dug wells, recharge shaft, etc.

Areas used for rainwater harvesting are :l Roof tops

17On Tips Notes

l Paved and unpaved areasl Water bodiesl Storm water drains

Components of Rainwater Harvesting System are categorised into following groups :l Catchment Area is the place from where the rain-water is collected.l Transportation System is to transport the rainwater from the collection surface to the storage reser-

voir.l A filter is used to remove suspended pollutants.l Storage facility is used to store water.l Recharge Structure is made to recharge ground-water.

Major parts of our country are facing the continuous failure of monsoon which has increased water scarcity.

Drastic use of groundwater due to ever-increasing population is leading to its constant depletion. Excessive heat waves during summers create a situation similar to drought in some places. It is imperative to take adequate measures to meet the drinking water needs of the people besides ir-

rigation and domestic needs. It is practiced in most of the large cities like Chennai, Bengaluru, Delhi and Mumbai. It became a part of the State policy. It increases the availability of surface water.

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