MagBook - India & World Geography PDF

A Must for Civil Services (Pre) Examination, State PCS & Other Competitive Exams INDIA & WORLD GEOGRAPHY Coverage of Important Facts from NCERT Books (Class 6-12) A Must for Civil Services (Pre) Examination, State PCS & Other Competitive Exams INDIA & WORLD GEOGRAPHY Co...

A Must for Civil Services (Pre) Examination, State PCS & Other Competitive Exams INDIA & WORLD GEOGRAPHY Coverage of Important Facts from NCERT Books (Class 6-12) A Must for Civil Services (Pre) Examination, State PCS & Other Competitive Exams INDIA & WORLD GEOGRAPHY Coverage of Important Facts from NCERT Books (Class 6-12) Authored By Vivek Sharma, Deepika Singh ARIHANT PUBLICATIONS (India) LTD. All Rights Reserved © PUBLISHER No part of this publication may be re-produced, stored in a retrieval system or by any means, electronic, mechanical, photocopying, recording, scanning, web or otherwise without the written permission of the publisher. Arihant has obtained all the information in this book from the sources believed to be reliable and true. However, Arihant or its editors or authors or illustrators don’t take any responsibility for the absolute accuracy of any information published and the damage or loss suffered thereupon. All disputes subject to Meerut (UP) jurisdiction only. ADMINISTRATIVE & PRODUCTION OFFICES Regd. Office 'Ramchhaya' 4577/15, Agarwal Road, Darya Ganj, New Delhi -110002 Tele: 011- 47630600, 43518550 Head Office Kalindi, TP Nagar, Meerut (UP) - 250002, Tel: 0121-7156203, 7156204 SALES & SUPPORT OFFICES Agra, Ahmedabad, Bengaluru, Bareilly, Chennai, Delhi, Guwahati, Hyderabad, Jaipur, Jhansi, Kolkata, Lucknow, Nagpur & Pune. ISBN 978-93-25798-04-5 PO No : TXT-XX-XXXXXXX-X-XX PRODUCTION TEAM Publishing Managers : Amit Verma Inner Designer : Mazher Chaudhary Project Head : Karishma Yadav Page Layouting : Sundar Bisht Project Coordiantor : Shivam Gupta Proof Reader : Sundip Giri Cover Designer : Bilal Hashmi Published By Arihant Publications (India) Ltd. For further information about the books published by Arihant, log on to www.arihantbooks.com or e-mail at [email protected] Follow us on  Earthquakes INDIA & WORLD GEOGRAPHY Weathering 1. The Universe and The Solar System 1-9 Erosion The Universe Cycle of Erosion Big Bang Theory Pulsating Theory 5. Climatology 40-52 Age of the Universe Atmosphere Components of the Universe Atmospheric Pressure Galaxies Atmospheric Circulations Stars Condensation The Solar System Clouds The Sun Humidity The Planets Rainfall Asteroids Air Masses Comets Fronts Meteors Cyclone Meteorites 6. Oceanography 53-58 Meteor Showers Oceans 2. The Earth 10-18 Relief Features of the Ocean Shape and Size of the Earth Temperature of Ocean Measurement of Earth’s Age Salinity of Ocean Motions of the Earth Ocean Currents Effects of Earth’s Motion Ocean Tides Distribution of Date and Time Coral Reefs International Date Line (IDL) 7. Biogeography 59-67 The Earth and the Moon Soil The Earth’s Magnetic Field Classification of Soil 3. Geomorphology 19-31 Natural Vegetation Introduction Major Biotic Regions Interior of the Earth Agro-Forestry Constituents of Earth 8. Human Geography 68-78 Earth Movements Evolution of Man Mountain System Races Plateaus Classification of Human Races Plains Population Landforms Produced by Different Processes Distribution of Population 4. Geomorphology II 32-39 Population Density Geomorphic Processes Population Growth Endogenetic Forces Human Development Report Volcanism Settlement  9. Economic Geography 79-96 Conventional Resources Agriculture Coal Types of Farming Petroleum Modern Agricultural Practices Oil Refineries in India Major Crops Non-conventional or Renewable Resources Cereal Crops Wind Energy Fibre Crops Solar Energy Cash Crops Nuclear Energy Beverage Crops Water Resources Food Security Marine Resources Fishing 14. Indian Agriculture 148-157 World Forest Resources Agriculture Types of Forests Features of Indian Agriculture Minerals Resources Green Revolution Types of Minerals Major Crop Types and Distribution Metallic Minerals Food Security Energy Resources New Initiatives in Agriculture Sector Industries Irrigation Major Industrial Belts Types of Irrigation Technique Transportation : Roadways, Railways, Waterways Multi-purpose Projects in India 10. Continents 97-108 15. Industrial Features of India 158-163 Africa Industries Antarctica Classification of Industries Asia Major Industries in India Australia Industrial Regions of India Europe North America 16. Transport, Trade and South America Communication in India 164-173 Roadways 11. India : Physical Aspects 109-131 Railways Geographic Profile Water Transport Geological Structure Pipeline Transport Physiography of India Air Transport Drainage Tele Communication Island Drainage International Trade Climate of India Natural Vegetation and Wildlife 17. India-cultural Settings 174-181 Scheduled Tribes 12. Indian States And Union Population of India Territories 132-138 States 18. Urbanisation In India 182-187 Union Territories Urban Social Process Evolution of Towns in India 13. Resources 139-147 Census Definitions of Urban Places in India Mineral Belts of India Urban Settlements According to Census of India Distribution of Minerals Trends and Patterns of Urbanisation in India ENVIRONMENT, ECOLOGY & 22. Climate Change 215-222 Causes of Climate Change BIODIVERSITY Greenhouse Effect 19. Ecology : Basic Concepts 188-195 Ozone Depletion Levels of Studying Ecology Impact of Global Warming Components of Ecosystem Effects of Climate Change Ecosystem Structures Parties to UNFCCC Functions of Ecosystem Kyoto Protocol Food Web Rio Declaration Food Chain Water Cycle 23. Disaster Management 223-228 Carbon Cycle Prevention Oxygen Cycle Mitigation Nitrogen Cycle Preparedness Phosphorus Cycle Response Ecosystem Patterns Recovery Types of Ecosystem Natural Disasters Man-made Disasters 20. Environment 196-204 Types of Environment Disaster Management in India Atmosphere World’s Major Conferences on Disasters Reduction Hydrosphere 24. Sustainable Development 229-236 Lithosphere Concepts of Sustainable Development Biosphere International Initiatives Towards Sustainable Types of Pollution Development Air Pollution Earth Summit, 2002 Water Pollution Rio + 20, 2012 Noise Pollution Land Pollution Sustainable Agriculture Marine Pollution Agro-forestry Organic Farming 21. Biodiversity and Its Conservation 205-214 Crop Rotation Mapping Diversity Bio-Fertilizers Biodiversity Biotechnology Hotspots International Conventions on Biodiversity Practice Set 1-5 237-256 Conservation Previous Years’ Solved Papers Set 1 257-270 Biodiversity in India Protected Area Network in India Previous Years’ Solved Papers Set 2 271-276 TOPICS FOCUS & TREND OF QUESTIONS The Universe and Solar System Biogeography Some of the important topics from examination perspective In this chapter, the components of biosphere, ecosystem and are various theories regarding the origin and evolution of the ecology explained that will help student to cope up the universe. After in-depth analysis of the previous year’s questions of evaluative perspective. Although, majority of question paper. This topic is very much important for the basic questions inclined towards this chapter. understanding of cosmology and Space technology. Human Geography The Earth This chapter is major sub-fields of the discipline of This is one of the important sections of the geography and geography that covers the world, its people, communities questions relates this chapter to another chapter that consists and cultures. of Earth’s interior, drainage pattern and landforms. This topic also concern of the mostly asked topics like-question of international date line and distribution of time and date. Economic Geography This chapter covers the location, distribution and spatial organisation of economic activities across the world. It Geomorphology helps students to understand the economic aspect of This chapter cover important aspects that is Earth file, geography. Economy is the bases of all the discipline and this landforms history, tectonic uplift which is very important from topic broaden the student’s horizon to understand the examination point of view. If we analyse the pattern of economic aspects of the geography. question in previous years, most of them are related Earth movements, land forms produced by different processes, constituents of Earth and also geomorphic processes. Continents This is one of the important chapter from examination point of view, in which the large landmass on Earth is explain Climatology according to their characteristics, features and extent. This chapter cover important points that help student to discover and explain the impacts of climate, so that society can plan its activities, design its builidings and infrastructure India : Physical Aspects This is one of the important topic from examination point of and anticipate the effects of adverse condition. In the past the view. It covers India’s frontier, relief features, i.e., mountains, questions have been asked regarding the important plateaus, plains, islands. Apart from this, Indian geography atmospheric pressure and circulations, Air Masses, fronts and should be given move emphasis because it is common for cyclone. Most of the competitive examination give special both prelim and mains while Indian geography is important weightage to this chapter and question will asked by relating for prelims, but the nature of question earlier it used to be other topics of geography, so it is very important topics on the mapped based or location based Indian geography, but examination point. current trends is mostly related with agriculture, environment angles. Oceanography This chapter consist of diverse topics reflect multiple blend of Indian States And Union Territories knowledge of the ocean world such as salinity and This topic deals with important aspects of States and UTs temperature, ocean ridge, currents, the living oceans and about their location, features and extent. Questions are coral reefs that will help student to tackle multidisciplinary frequently asked almost all exams about Jharkhand, Andhra questionnaires. This topic provides information to the very Pradesh, Maharashtra and Madhya Pradesh. common asked question related to ocean tides, coral reefs and ocean current. Resources master trivial compilation of every aspects related ecology, environment and biodiversity like other topics, environment The topic deals with the resources distribution about minerals, and biodiversity can be classify into two heads. industry, energy which very much important for examination. Statis Indian Agriculture Basic theoretical and static stuff such as biomes, in-situ, ex-situ This topic deals with the India’s agriculture patterns, modes of wildlife conservation. distribution and contribution in GDP. Current Based Industrial Features of India IPCC report, kyotoprotcol supreme court order on xyz issue, This topic deals with industrial development, pattern of cleaning of yamuna, Ban on minning etc. industries, agro-based industries and major industrial cluster from examination point of view. Climate Change This topic deals with significant and lasting change in Transport, Trade and Communication statistical distribution of weather patterns over period ranging in India from decades to millions of years. It is become international This topic consisted the major topics from which questions topic of discussion then how can examination would be are frequently asked such as trends in transports, major ports destituted. It is one of impudent topic after environment and trade regions and network of communication. biodiversity which has given special weight age because it is the only regulating factor of the sub-field of the geography. Every competitive examination asked question by the factor India-Cultural Settings of the climate change relate with other topics through affects. This topic deals how regional variation formed India’s distinct cultural setting. Chapter 18 (Demographic Features of India) This chapter is sub-part of human geography, which deals Disaster Management with the distribution of India’s population. This topic deals with environmental impacts on using resources, disaster prevention, disaster preparedness, relief, recovery. Settlement Geography of India This topic deals with rural settlement, urbanisation and urban agglomeration. Sustainable Development This is very important topic from examination point of view. This topic covers the various facets of sustain ability and also Ecology; Environment; Biodiversity describe an economy in equilibrium with basic ecological This is the major important topic from examination point of support system. As far as the new syllabus, a significant view. It covers some important topics such as importance of number of questions are being asked from on these topic environment, affect of climate on environment, global every year and also in creases the number of question day by warming, tropic, food chain, species variation and biome or day. Apart from examination, this topic became world wide planet. This topic is given special weightage by the UPSC and agenda. Hence, it became prominent and important for any other competitive examination. The level of question had examination point of View. asked was pro-concept and current based. Hence, the topic is  India & World Geography Chapter one The Universe and the Solar System Universe The Big Bang Theory — All the heavenly bodies i.e. stars, — It is the most acclaimed theory proposed Universe is the sum total planets, satellites, asteroids, meteors by Georges Lemaitre in 1930s and later strongly evidenced by George Gamow, of all the potentially comets, dust and gases are called celestial bodies, which together form the which explained the modern Big Bang knowable objects. The theory. universe. The science of studying these study of universe on a heavenly bodies is known as astronomy — Theory states that, at the beginning, all grand scale is called and the scientists who practice matter forming the universe existed in one cosmology. The universe astronomy are called astronomers. place in the form of a tiny ball (singular or primeval atom) with an unimaginably includes planets, stars, galaxies, the contents of Theories about Universe small volume, infinite temperature and — Universe has been fascinating since indefinite density. intergalactic space, the ancient times. Various scholars have — Around 15 billion years ago, a vast smallest sub-atomic presented their views on universe. These explosion occurred and the primeval atom particles and all matter theories can be put into two categories: disintegrated giving rise to space and time and the expansion of the universe that still and energy. (i) Early Theories continues till today and will continue — Geocentric Theory The theory is further. proposed by Ptolemy in AD 140, which — The expansion of matters further formed states that the Earth is the centre of the galaxies and these galaxies are universe. continuously expanding and moving away — Heliocentric Theory The theory is from each other in an accelerated velocity proposed by Copernicus in AD 1543, and in the process cooling the universe. according to which the Sun is the centre — The Big Bang or the expanding universe of the universe. is now proven by the discovery of the — In 1805, British astronomer Hershel Cosmic Microwave Background Radiation studied universe with the help of (CMBR) and Wilkinson Microwave telescope and stated that the solar Anisotropy Probe (WMAP). system is merely a small part of a galaxy. — Another important astronomic observation — An American astronomer, Edwin P called red shift also proved the expansion Hubble in 1925 said that the universe of universe. has a diameter of 2.5 billion light years — The recent experiments at the Large and is composed of several galaxies. Hadron Collider (LHC), built by the European Organisation for Nuclear (ii) Modern Theories Research beneath the Franco-Swiss There are four main modern theories put border near Geneva, Switzerland, aims to forward to explain the origin and evolution of recreate conditions just after big bang to the universe: have a better understanding of the phenomenon. 2 Magbook ~ Geography–India and World Red Shift Theory — The fate of the universe is determined by a struggle between the momentum of expansion and the pull of — Light is formed of a band of colours called spectrum. Violet gravity. The rate of expansion is expressed by the Hubble colour has the shortest wavelength and lies at one end of Constant (Ho) while the strength of gravity depends on the spectrum and red light has longest wavelength and lies the density and pressure of the matter in the universe. at another end. — If the pressure of the matter is low then the fate of the — The movement of a star or galaxy affects its light as seen universe is governed by the density. If the density of the by the observer. When the star is approaching the observer universe is less than the ‘critical density’, which is the light shifts to the blue end of the spectrum and the proportional to the square of the Hubble Constant, then light shifts to the red end when the star recedes away. the universe will expand forever. — This is known as the doppler effect or doppler shift. The — If the density of the universe is greater than the ‘critical doppler shift of the galaxies show that they are receding density’, then gravity will eventually win and the universe and that the universe is in a state of rapid and accelerated will collapse back on itself, which is called big crunch. rate of expansion. This astronomical observation is known as red shift. — This strange form of matter is now referred as dark energy. If the dark energy infact plays a significant role in Steady State Theory the evolution of the universe, then in all likelihood the — Bondi, Gold and Fred Hoyle developed this theory. universe will continue to expand forever. According to this theory, the number of galaxies in the observable universe is constant and new galaxies are Components of the Universe continuously being created out of empty space, which fill — Our universe has a foamy structure. Considering only the up the gaps caused by those galaxies, which have crossed largest structures the visible universe is made up of the boundary of the observable universe. As a result of it, filaments, superclusters and galaxy groups and clusters. the overall size of mass of the observable universe remains The galaxy groups and clusters in combined form are constant. Thus, a steady state of the universe is not called superclusters, which are on turn form part of disturbed at all. walls, which are also parts of filaments. Pulsating Theory — The visible part of universe is concentrated in certain parts in a complex scaffold that surrounds a network of — According to this theory, the universe is supposed to be enormous cosmic voids or vast empty spaces. expanding and contracting alternately i.e. pulsating. At present, the universe is expanding. — In addition to the ‘normal’ matter that makes up the visible parts of the universe, scientists have discovered — According to Pulsating theory, it is possible that at a certain that there are vast amounts of unseen matters called time, the expansion of the universe may be stopped by the dark matters. In proportion gravitational pull and it may contract again. After it has —Dark energy : 68% been contracted to a certain size, explosion again occurs —Dark matter : 27% and the universe will start expanding. The alternate —Visible matter : 5% expansion and contraction of the universe give rise to pulsating universe. The visible matter of the universe are composed of: Hydrogen : (72-75%) Age of the Universe Helium : (23-26%) Other elements : 8) found in the hot deserts of the content of organic matter in the upper 80 cm of the soils mid-latitudes. Lime forms a deposition over the upper and no permafrost. The amount of organic matter is at layer of the soil. Thin soils having poor horizonizalian. least 20% to 30% in more than half of this thickness, or Near absence of humus or low humus content. the horizon that is rich in organic matter rests on rock or rock rubble. Red Desert Soil Inceptisols — This is the soil of hot deserts in the tropical region. It is characterised by deposition of lime near the surface and — Inceptisols have a wide range in characteristics and occur absence of humus. Moderate to high fertility depending on in a wide variety of climates. They can be formed in nitrogen (N) content. Productive if abundant irrigation is almost any environment, except for an arid environment available and salt removed. and the comparable differences in vegetation are great. Magbook ~ Biogeography 63 Entisols Mollisols — The unique properties common to entisols are dominance — The unique properties of mollisols are a combination of a of mineral soil materials and absence of distinct very dark brown to black surface horizons (mollic pedogenic horizons. The absence of features of any major epipedon) that makes up more than one-third of the set of soil forming processes is itself an important combined thickness of A and B-horizons. distinction. — Mollisols characteristically form under grass in climates — Entisols are soils in the sense that they support plants, but that have a moderate to pronounced seasonal moisture they may be in any climate and under any vegetation. deficit. Vertisols — Some mollisols, however, formed under a forest ecosystem — These soils have markers of processes related to the and a few formed in marshes or in humid climates. failure of soil materials along shear planes (slickensides). — Mollisols are extensive soils on the steppes of Europe, Because the soil material moves, the diagnostic properties Asia, North America and South America. have many accessory properties. — Among them are a high bulk density when the soils are Soil Erosion dry, low or very low; hydraulic conductivity when the soils — Geologic erosion or Natural erosion is the action of the are moist, an appreciable rise and fall of the soil surface wind, water, ice and gravity in wearing away rock to form as the soils become moist and then dry and rapid drying soil and shape the ground surface. Except for some as a result of open cracks. stream and shore erosion, it is a relatively slow, — The unique properties common to vertisols are a high continuous process that often goes unnoticed. The natural content of clay, pronounced changes in volume with erosion of soil is accompanied by formation of new soils changes in moisture, cracks that open and close as the nature always maintains the universal equilibrium periodically and evidence of soil movement in the form of and harmony. slickensides and of wedge-shaped structural aggregates — Accelerated erosion is the speeding up of erosion due to that are tilted at an angle from the horizontal. Black soil of human activity. Farming, construction, logging and mining Deccan plateau is a type of vertisol. are the principle causes of accelerated erosion. These activities radically upset the delicate balance that nature Oxisols has developed between rainfall and runoff. — The unique properties of oxisols are extreme weathering of — Runoff water is a major factor for soil erosion. Runoff most minerals other than quartz to kaolin and free oxides, water includes sheet erosion that ripped off top fertile soil, very low activity of the clay fraction and a loamy or clayey rill erosion, gully erosion that erode the soil and form texture (sandy loam or finer). badland topography and slip erosion that are caused by — Oxisols characteristically occur in tropical or sub-tropical hydraulic pressure existed by moisture penetrating into regions, on land surfaces that have been stable for a long the soils during the heavy rains. time. Spodosols Soil Conservation Methods — Spodosols have markers in at least an upper sequum of No-Tillage Farming Growing of crops without removing the dominant processes that translocate humus and existing plant cover and previous crop residues. aluminum or humus, aluminium and iron, as amorphous Minimum Tillage Farming Shallow ploughing only to the depth materials. needed to ensure quick seed germination and leaving crop — The unique property of spodosols is a B-horizon, residues and ground litter to protect the soil. consisting of an accumulation of black or reddish Contour Cropping Ploughing and planting along the contours of amorphous materials that have a high cation exchange the land, so that water cannot runoff the soil as easily. capacity. Strip Cropping Alternating strips of close growing plants (such as Ultisols grass or clover) and regular crops (such as corn, cotton, — Ultisols, like alfisols, have markers of clay translocation, potatoes). The strips of close growing plants, slow water but they also have markers of intensive leaching that are runoff and when combined with contour cropping can reduce absent in alfisols. soil erosion by 75%. — The unique properties common to ultisols are an argillic Terracing Developing flat, step-like terraces to reduce water runoff on very steep slopes. horizon and a low supply of bases, particularly in the lower horizons. 64 Magbook ~ Geography–India and World Soil Conservation Methods — Roots are shallow due to availability of much water and allows to tap the abundant nutrients found in the ground Crop Rotation and Cover Crops Planting fields periodically with layer. These forests are shrinking. close growing secondary crops that allow less soil erosion and planting dense growing cover plants when no crop is — Temperate coniferous forests found in Japan, China, being grown. Europe, North America etc (only in Northern hemisphere). These are cone-shaped to adopt snowfall. These are Gully Reclamation Seeding gullies with quick-growing plants and evergreen and forests are having only one variety of tree in using check dams of manure and straw to reduce erosion. each area i.e. pine, fir, spruce etc. Windbreaks ( Shelter belts) Planting rows of shrubs and trees as — Benefits of forest includes contribution of oxygen to wind-breaking barriers along the windward edges of atmosphere, formation of rains, providing natural croplands to reduce soil loss from wind. Replanting trees on land no longer used to grow crops. resources, have medicinal value and provide place for recreational activities. It also provide natural habitat, Not Planting Marginal Land Raising crop yields on good land to prevent soil erosion, provide catchment area for drainage reduce pressure on farm marginal land. basins. Land Classification and Zoning Classifying land according to its suitability for cultivation and using land use zoning and Biotic Regions of the World controls to prevent the loss of good cropland and the planting — Biome is a biotic community characterised by of marginal land. distinctiveness in life forms of the important climax species. Trewartha, on the basis of availability of soil, Natural Vegetation water and temperature, has divided the biomes of the world into the following five categories: — Natural vegetation refers to plants which have grown naturally and not planted by human beings. Primary (i) Tropical Rainforest (Selva) vegetations are untouched, unspoiled forests that exists in — Unchanging climate of high temperatures and very heavy its original condition. Secondary vegetations are the rainfall. Luxuriant growth, evergreen variety. Light is the forests that has been disturbed in someway, naturally or limiting factor, not nutrients. Trees consist of several layers artificially and have fewer varieties of plants. and little undergrowth. — Three major types of natural vegetation are forest, — Contain a large number of epiphytes (stranglers). Climbers grassland and deserts with many sub-groups. Forest types including lianas are numerous. Trees have buttress or stilt can be classified as tropical rainforests, temperate roots and drip trips. deciduous forests and temperate coniferous forests. — Abundance of detritivorous, particularly ant and termites. Grasslands can be classified as tropical savannas and Insects are very large; moths have wingspan of 30 cm; temperate grasslands. Desert vegetations can be divided spiders are large enough to eat small birds. Dominated by into hot desert vegetation and cold tundra vegetation. snakes (anaconda) and reptiles. — Tropical rainforests are found mainly along the equator between tropics, temperate forests are found mainly (ii) Tropical Savanna between tropics and sub-Arctic circles in both the — Long dry warm season and short rainy season, water is hemisphere and coniferous forests are only found in the limiting factor. Dominated by grasses and water Northern hemisphere between 60°N and 70° N. availability determines tree growth. Trees exhibit various — At lower temperature less than 6°C, few plants can grow drought resistant features consist of spines (Acacia), and at warm temperature above 20°C, allow abundant baobab is bottle-shaped. plant growth. — Vegetation shows many adaptations to fire. Most trees are — Precipitation also influence to vegetation positively. Most fire resistant, therefore, species diversity is low. Some forests grow with high rainfall above 1000 mm a year and seeds are covered with hard shell, which breaks at 80°C in moderate rainfall regions between 200 mm and only. Most of the trees reproduce themselves by throwing 1000 mm, grasslands are found and precipitation below up suckers not many by seed germination. Possess thick 200 mm only. bark and thick bud scales. — Tropical rainforests are very dense and has three distinct — High productivity and abundance of easily digestible food layers i.e. emergent, canopy and undergrowth, found has led to large number of first order consumers. mainly in Amazon basin, South-East Asia, Central Africa Encourages large numbers of herds of growing etc. Epiphytes and lianas are predominants in this forests mammals–Lions, big cats, hunting dogs, jackals and to overcome shortage of sunlight. hyenas. Magbook ~ Biogeography 65 — Dominated by hoofed mammals adopted to running on flat — Except for Ptarmigan, tundra birds are migratory using the plain–wild beast zebra, giraffe. The largest animals are short period of reproduction and surviving the rest of the conspicuous related to size–elephant, giraffe, rhinoceros; year elsewhere–geese, shore-birds and songbird. related to mobility–gazelles, ostriches, other flightless birds Subcutaneous fat-insulator prevents heat from body. such as emus. — Various adaptations—some ants and termites survive in Major Biotic Regions intense fire by moving underground; most animals display — The biomes are determined by the degree to which remarkable camouflage, ungulates are agile and swift-footed moisture is available to plants in a scale ranging from to escape sharp-clawed sharp-toothed predators. abundant (forest biome) to almost none (desert biome). But, within each biome, conditions of temperature are (iii) Tropical Desert vastly different from low to high latitudes. — Extremely hot with unreliable and scarce rainfall. Plant life Forest Biome adapted to aridity. — A forest is defined as a plant formation consisting of trees — Two general classes of vegetation are: growing close together and forming a layer of foliage that —Perennials succulents adjust to aridity by various avoiding largely shades to ground. The forest biome spans a great mechanisms–extensive root system, transpiration reduction, dying back of leaves as in many grasses, heavy cuticular and climatic range, from wet equatorial to cold sub-Arctic. epidermal layers, waxy coating on leaves, sunken stomata. — Forest biome includes following forest types: —Ephemerals have short life cycle and may form a fairly dense The Equatorial Rainforest stand after rainfall. They evade drought develop vigorously and produce large number of fruits and flowers during rain. — It extends over the Amazon lowland of South America, Congo lowland of Africa, a coastal zone extending — Animals show various adaptations–escape involves Westward from Nigeria to Guinea and in South-East Asia aestivation or dormancy, seasonal migration, nocturnal from Sumatra on the West to the islands of the Western habit, kangaroo rat seals its burrow by day to keep Pacific on the East. chamber moist, obtains water by own metabolic process and from hygroscopic water in food, liberates The Tropical Rainforest concentrated urine. — Areas include Southern and South- Eastern Asia in Western ghats of India, coastal Myanmar, coastal Vietnam (iv) Taiga Biome and the Philippines, Eastern Brazilian coast, the — Winters are long and severe, summers are cool and brief, Madagascar coast and North- Eastern Australia. very low mean annual temperature. Conical shape, smooth leaf surface, needle leaf, sunken stomata. The Temperate Rainforest — Covers South-Eastern USA, Southern Japan, Southern — Evergreen and needle is a design that helps active useful Brazil, Uruguay and Northern Argentina, South-Eastern working temperatures in temporarily productive periods at South Africa, European highland from France in the West minimum cost of maintenance. to Slovakia in the East, Eastern Chinese coast, — Large mammalian herbivores (deer and bear) are adapted South-Eastern coast of Australia and New Zealand. to make use of regenerating forest in burned areas for browse. Migratory animals—aestivation, dormancy. The Monsoon Forest — Presents a more open tree growth than the equatorial and (v) Tundra Biome tropical rainforests. The most important feature of the — Extremely cold and dry. Limiting factors are severe cold monsoon forest is the deciduous nature of most plant and shortage of radiant energy. Adapted short growing species. season and extreme cold climate. Lack of tall plants as a consequence of the requirement to balance a heat budget Savanna Biome and conserve moisture. — This biotic region consists of a combination of trees and — Summer thaw turns it into a quagmire of puddles, bogs grassland in various proportions. The appearance of the and shallow lakes. Surface is covered with a mat of vegetation can be described as park-like, with trees spaced lichens, mosses, grasses, sedges. singly or in small groups and surrounded by or interspersed — During short summers, large number of migratory birds, with surfaces covered by grasses or by some other plant life especially waterfowl invade the tundra to feed on. form, such as shrubs or annuals in a low layer. 66 Magbook ~ Geography–India and World Grassland Biome — Carbon credit earning through Clean Development Mechanism (CDM) will be an additional income benefit by — This biotic region consists of an upland vegetation largely social forestry for afforestation/reforestation and wasteland or entirely of herbs, which may include grasses, grass-like development. It’s a community based work on massive plants and forbs (broadleaf herbs). plantation through panchayat/ village assembly involving — The important formation classes of grasslands are: farmers, village workers, government and private bodies 1. Prairies 2. Steppe 3. Pampas etc, under Joint Venture Programme. 4. Veld 5. Downland Agroforestry — Prairies are characterised by tall, deep rooted grasses of the interior North American plains. The Steppes cover a — Agroforestration is an integrated approach of combining belt extending from Hungary in the West to Mongolian and agricultural and forestry technologies to create more Eastern Chinese plains in the East. Other important diverse, productive, profitable, healthy and sustainable grassland areas include Pampas of South America, Veld land use systems. It is also helpful in soil conservation plateau of South Africa, Northern and Central African and and increasing ecological aspects. Agroforestry is well the Downland in Australia. practiced in Bangladesh and India. — Agri Silviculture System It refers to that type of system in Desert Biome which the agricultural crops and forest tree species are — The desert biome, associated with the climates of extreme grown on same piece of land at unit period of time. e.g. aridity, has thinly dispersed plants and hence a high growing of teak and onion. percentage of bare ground exposed to direct insolation and — Silvo Pastoral System It refers to that type of system in the forces of wind and water erosion or freeze-thaw action. which the silvicultural tree species are grown in combination with pastoral grass. e.g. growing of teak and Social Forestry berseem grass for fodder purpose. — Social forestry is a management and protection of forest — Agri Silvo Pastoral System It refers to the system that and afforestation on the degraded land with the purpose combines agricultural crops, silvicultural tree species and of helping in the environment, social and rural grasses on same piece of land at a unit period of time. development.  Self Check Build Your Confidence 1. Consider the following characteristics 8. In which of the following soil forming processes, 1. Long and severe winter. organic acids of soluble chelates are formed? 2. Conical shape smooth leaves. (a) Leaching (b) Podzolisation 3. Low species diversity. (c) Laterisation (d) Salinisation 4. Large mammalian herbivores. 9. The nature of vegetation in the world changes Which type of biome has above characteristics? according to (a)Taiga biome (a) latitude (b) climate (b) Tundra biome (c) nature of soil (d) All of these (c) Selvas (d) Tropical savanna 10. Chernozems are (a) silica rich temperate grassland soils 2. Contour bunding or cropping is a method of soil (b) iron rich humid upland soils conservation used in [IAS 2013] (c) humus rich dark brown colour soils in semi-arid region (a) desert margins, liable to strong wind action (d) humus rich tropical grassland soils (b) low flat plains, close to stream courses, liable to flooding (c) scrubland, liable to spread to weed growth 11. Hard pan and clay pan in soil are found in (d) None of the above (a) A- horizon (b) B- horizon (c) C- horizon (d) D- horizon 3. Which of the following is/are unique characteristic(s) of equatorial forest? [IAS 2013] 12. If a tropical rainforest is removed, it does not regenerate quickly as compared to a tropical 1. Presence of tall, closely set trees with crowns forming a deciduous forest. This is because [IAS 2011] continuous canopy. (a) the soil of rainforest is deficient in nutrients 2. Co-existence of a large number of species. (b) propagules of the trees in a rainforest have a poor 3. Presence of numerous varieties of epiphytes. viability Select the correct answer using the codes given below (c) the rainforest species are slow growing (a) Only 1 (b) 2 and 3 (d) the exotic species invade the fertile soil of rainforest (c) 1 and 3 (d) All of these 13. In dry regions, the leaf size becomes smaller due to 4. Which one of the following pairs is correctly matched? (a) reducing metabolism (a) Latosols : Scrubs (b) maintaining growth (b) Chernozem : Savannas (c) reducing transpiration (c) Sierozem : Selvas (d) protecting plant from animals (d) Podzsol : Conifers 14. Soil water available to plants is maximum in 5. In the hot and humid regions of the tropics, the (a) clayey soil (b) silty soil characteristic soil is (c) sandy soil (d) loamy soil (a) laterite (b) pedocal (c) pedalfer (d) alluvial 15. The capacity of a soil to hold water against the pull 6. Which of the following regions are characterise by little of gravity is called as undergrowth trees of several layers? (a) storage capacity (a) Tropical savanna (b) Tropical rainforest (b) wilting capacity (c) Tropical desert (d) Taiga (c) wilting point 7. Which of the following soils is formed in the regions of (d) hygroscopic capacity ample rainfall and is characterised by abundance of 16. Which type of soil retains maximum amount of aluminium and iron? water? (a) Pedocal (b) Pedalfer (a) Loam (b) Sandy (c) Peat (d) Histosols (c) Clay (d) Red 1. (a) 2. (d) 3. (c) 4. (d) 5. (a) 6. (b) 7. (b) 8. (b) 9. (d) 10. (c) 11. (b) 12. (a) 13. (c) 14. (a) 15. (d) 16. (c) Chapter eight Human Geography Evolution of Man Characteristics of Races Human beings are — Scientists believe that the gradual The best marked race characters are as follows: vertebrates and belong evolution of man on the Earth started Colour of the Skin to class Mammalia. in the Tertiary period. Paleontological — The colour of the skin has always been held evidences show that the first ancestors Within the class as specially distinctive. The coloured race of man lived in the African continent, portraits of ancient Egypt remain to prove Mammalia, man belongs 65 million years back. the permanence of complexion during a to the order primates, a — Ramapithecus is the oldest fossil lapse of a hundred generations, group that originated ancestor of man in the direct line of distinguishing coarsely, but clearly the types evolution. It lived for a short period of the red-brown Egyptian, the yellow-brown about 65 million years between 16 and 18 million years ago. Canaanite, the comparatively fair Libyan and ago and includes not — Australopithecus (African ape-man) the black Negro. only monkeys and apes, lived in Africa about 5 million years — These broad distinctions have the same kind but also the lorises, ago that ultimately gave rise to genus of value as the popular terms describing lemurs and tarsiers. homo, about 2 million years ago. white, yellow, brown and black races, which Humans belong to the — Homo Habilis (the handy man) lived in often occur in ancient writings and are still Africa about 2 million years ago. Homo used. family Hominidae, in erectus appeared about 1.7 million — The varieties of the human skin may be which homo sapiens is years ago and is believed to have followed from the fairest hue of the Swede the only living species. migrated to Asia and Europe. and the darker tint of the Provencal, to the — Neanderthal man (Homo sapiens withered leaf brown of the Hottentot, the neanderthalensis), a primitive form of chocolate brown of the Mexican and the homo sapiens, was common in Europe brown-black of the West African. and Asia. They resembled the modern Hair human being though they were relatively short, stocky and well built — Hair’s structure and arrangement is a better physically. indication of race than its tint. — The Neanderthal man was wiped out — The hair differs in quantity between and gave way to the more efficient scantines of the body of the Mongol and Cro-Magnon about 34000 years ago. profusion on the body of Aino while as to the arrangement on the scalp, the tufts of the — Homo sapiens began to spread all over Bushman contrast with the more equal the world after the last glacial period. distribution on the European head. Races — The straight hair of the North American or Malay is recognisable at once as different — Race is a term used for large group of from the waving or curling hair of the people with some basic inherited European and both from the naturally freezed physical characteristics in commons, hair of the Negro. e.g. skin colour, hair, facial features and head shape etc. Three major racial Stature stocks are Caucasoid, Mongoloid and — Stature is by no means a general criterion of Negroid. race and it would not, for instance, be Magbook ~ Human Geography 69 difficult to choose groups of Englishmen, —Thyroid Gland Due to inactivity of this gland, people of Mongolian race have Kafirs and North American-Indians, whose flat face, small forehead. mean height should hardly differ. —Adrenal Gland This gland influences the complexion. — Proportions of the limbs, compared in length — Besides these, adaptation, mutation and migration are also important with the trunk, have been claimed as factors influencing the racial differences. constituting peculiarities of African and Physical Characteristics of Races American races; and other anatomical points, Characteristic Caucasoid Negroid Mongoloid such as the conformation of the pelvis, have /Races speciality. But inferences of this class have Skin colour Light reddish Brown to Light yellow to hardly attained to sufficient certainty and white to olive brown-black. yellow-brown. generality to be set down in the form of rules. brown. Some are Some are Some are reddish brown. yellow-brown. brown. Skull Head hair Light blonde to Brown-black in Brown to — The conformation of the skull is second only dark brown in colour. Coarse in brown-black in to the colour of the skin as a criterion for the colour. Fine to texture. Curly to colour. Coarse in distinction of race. medium in texture. frizzly or woolly in texture. Straight Straight to wavy form. in form. Classifications of Human Races in form. — Different ethnologists have classified human Body hair Moderate to Slight. Sparsely profuse. distributed. races differently. Among these, the most Eye colour Colour is light Brown to Brown to dark important are as follows: blue to dark brown-black. brown. —Caucasoid Nordic, Alpine, Mediterranean brown. —Mongoloid Mongolian, Melanesian and Special eye Lateral eye-fold. Vertical eye-fold. Epicanthic fold. American Indian features —Negroid Negro, Melanesian, Pygmy Black. Head form Dolichocephalic to Predominantly Predominantly —Capoid Bushmen/Hottentots. brachycephalic. dolichocephalic. brachycephalic. Height is medium Height is low to Height is medium. —Australoid Australian Aboriginal and Papuans. to very high. medium. Face Narrow to medium Medium broad to Medium broad to Denisovan broad. narrow. Strong very broad. The Denisovan are extinct species or sub-species of prognathism is Cheekbones are archaic humans of the genus Homo. Scientists have very often present. high and fat. discovered jawbone of this ancient species from the Nose Leptorrhine to Platyrrhine, Mesorrhine to Tibetan Plateau. It was identified on the basis of the mesorrhine. usually bridge is platyrrhine. analysis of protein. This species existed 1,60,000 Usually bridge is low. Usually bridge is years ago. Earlier its evidences were found in the high. low to medium. Denisova Cave in the Altai mountains in Siberia. Factors Influencing the Racial Population Differences — Population geography is closely related to demography (the study of population statistics and trends). Population Geography is concerned Climatic Changes with the understanding of the regional differences in the Earth’s — A unique race evolves due to living in the covering of people. same climatic conditions for very long time. e.g. white races in the colder regions or Distribution of Population Negroid races in the Mediterranean tropical — World population distribution is uneven. There are places having region. Due to change in climate, racial sparse population and dense population. Sparsely populated places characteristics are also changed. e.g. brown tend to be difficult places to live. These are usually places with hostile complexion of Mestizo. environments, e.g. desert areas of the world. Places, which are Hormonal Influence densely populated are habitable environments, e.g. Europe. Less than — Hormones also influence the differences in 10% of the world’s population lives in the Southern hemisphere, and races 80% lives between 20° degrees and 60° North latitude. —Pituitary Gland Due to higher activity of this Factors Affecting Distribution gland, people of Caucasian race are tall, well built, with beautiful and proportionate nose and Physical Factors broad chin. — Landforms, climate (temperature, amount of precipitation and length of crop growing season), vegetation, soils and water supplies. 70 Magbook ~ Geography–India and World Climatic Conditions Means of Transport and Communication — Climate influences growth of population. Moderate climate — Highly developed means of air, surface and water add to leads to the growth of population because it is pleasant and the density of population in a particular region because refreshing. In these regions, density of population is high. there the people can manage and carry on agricultural, On the other hand, people do not like to live in too hot and commercial as well as industrial activities. too cold climates. — Economic Factors Resources, accessibility, diseases and Natural Resources pests, stage of development of economy etc. — The regions having rich wealth of natural resources like coal, — Political Factors Stability of government, political scope water, minerals and forest wealth, promote economic growth for development, efficient bureaucracy, restrictions of and income, thus, favour the growth of population. This is international boundaries etc. the reason why North-West Europe, Bihar and West Bengal have high density of population. Densely Populated Regions — Important areas in the world where the average density Soils of population is 200 or more persons per square km. — Rich and fertile soil always help in the growth and — These highly dense regions usually coincide with either development of agricultural activities with substantially high fertile river valleys or urban conurbations. yield per hectare. This is so, because fertile lands produce a variety of crops to support dense population, so East and — While the regions of East Asia and South Asia South Asian region and Northern plains of India are densely correspond to agriculturally exploited river plains and populated. It must be noted here that all the river valleys of deltas, the regions of North-West Europe and Eastern the world are densely populated regions of the world. North America correspond to industrial agglomerations. Important Tribes of the World Aborigines Australoids, native people of Australia. Kamba Bantus of Central Kenya. Ainu Caucasoids of Japan. Kikuyu Agricultural tribes of Kenya belonging to Negroid Red-Indian Mongoloid racial stock distributed in various parts of racial stock. North, Middle and South America. Lapp Caucasoid group of people found in Northern Bantu Negritoes of Central Africa. Scandinavia, Sweden, Northern Finland, Norway and Beduoins Pastoral tribes in Arabia, Syria and North Africa. Black North-Western region of Russia. fellow Australian aborigines. Semang Group of Negroes having a well proportioned sturdy Bushmen A group of Negroid racial stock known as khuai or built body with mesocephalic head, round face, short flattened and very broad nose, but without thick san, confined mainly to the Kalahari desert. everted lips, found in Malayan Peninsula and East Characterised by presence of steatopygia. Sumatra. Chukchi Mongoloids inhabiting Chukchi Peninsula. Shan Inhabitants of South China, Assam, Myanmar. Dravidian Caucasoid racial stock in Peninsular India. Vedda Short statured inhabitants of Sri Lanka with the Fellah Agricultural labourers of Nile valley in Egypt. smallest heads. Han Original inhabitants of China. Yuit Inhabitants of Siberia and St Lawrence island of Hausa Original inhabitants of Nigeria. Alaska. Inca Inhabitants of Peru in Kulko valley. Zulu Bantu speaking people of South Africa’s Cape Jarawa Inhabitants of Andaman. Province. Endangered Tribes of the World Hadza They live in Tanzania. Their number is merely 200. Yukagir Population of this tribe of Siberian region is merely They speak the language similar to Bushman. 2000. They are hunters and hunt the reindeers. Kung This tribe lives in Kalahari region. Genetic and Chukchi This Palco-Asian language speaking tribe lives in Paleontological evidences show that once they lived in North-Eastern Siberia and North America. extensive area of Africa. Onge This tribe of Negrito group, living in Andaman, has only Apache The population of this tribe, living in the plains of Oklahoma 100 members. This fast disappearing tribe migrated in of USA is 1000. They had migrated here from Siberia. this region from Africa, thousands of years back. Yanomami This nearly extinct tribe found at the boundary of Brazil Sentinali This is also an endangered tribe of Andaman and and Venezuela. Nicobar islands. Magbook ~ Human Geography 71 Sparsely Populated Regions Factors Affecting Population Density — Over 70% of the land surface is sparsely populated i.e. less — Following are the factors that affect population density: than 50 persons per square kilometre. In general, the hot, cold, arid and mountainous areas are Physical Factor High Density Low Density sparsely populated, which may be classified under the Relief (shape Lowland which is flat, e.g. Highland that is following categories: and height of Ganges valley in India. mountainous, e.g. —Deserts and arid lands land) Himalayas. —Ice caps and cold regions Resources Areas rich in resources Areas with few (e.g. coal, oil, wood, resources tend to be —Mountainous regions fishing etc) tend to sparsely populated, —Tropical rainforests densely populated, e.g. e.g. The Sahara. Western Europe. Moderately Populated Areas Climate Areas with temperate Areas with extreme — Tropical savannas climates tend to be climates of hot and — Temperate grasslands densely populated as there cold tend to be — Tropical coastlands is enough rain and heat to sparsely populated, grow crops, e.g. UK. e.g. the Sahara — Temperate coastlands Desert. Political Countries with stable Unstable countries Important Facts of the World Population governments tend to have tend to have lower a high population density, population densities Nearly 75.5% of the total population of the world lives in less e.g. Singapore. as people migrate, developed regions of Latin America (8.4% of world’s e.g. Afghanistan. population), Africa, Asia, Polynesia, Melanesia and Social Groups of people want to Other groups of Micronesia. All these regions are passing through the first or live close to each other people prefer to be the second stage of demographic transition. for security, e.g. USA. isolated, e.g. 58.2% of the total population of the world live in Asia Scandinavians. (erstwhile USSR excluded), 5.8% in erstwhile USSR; 20% and Economic Good job opportunities Limited job 16.7% of world’s population are found in China and India, encourage high opportunities cause respectively. After these, USA, Indonesia, Brazil, Pakistan, population densities. some areas to be Bangladesh, Russia, Japan and Nigeria etc come in that order. Particularly in large cities sparsely populated, in MEDCs and LEDCs e.g. Amazon 80% of the world’s population concentrated in 20% of the around the world. rainforest. world’s total land area. 90% of the world’s population is distributed in the Northern hemisphere. Carrying Capacity — Carrying capacity is the maximum population size that a Population Density species can maintain indefinitely in a given area, without — Population density is the degree of compaction in a diminishing the capacity of the area to sustain the same population or the closeness of persons living on a given population size in the future. It is function of both the surface. resource requirements of the organism and the size and It may be assessed in the following various ways and resource richness of the area. Biologists distinguish using various techniques: between biophysical carrying capacity and the maximum —Crude density or Arithmetic density is the most common population size that could be sustained bio-physically method. It is a straight measurement of the total number of under given technological capabilities and social carrying people per unit of land. capacity. —Nutritional or Physiological density is the number of persons per unit of area of cultivated land. It is a refined method of Kinds of Population on the Basis of Growth calculating man land ratio. There are three kinds of populations: —Agricultural density is a density of agricultural population over (i) Rapidly growing population is a population, which has high cultivated area. It is an useful index of man-land relationship birth rate and low death rate, so there are more number of in primarily an agrarian context. young individuals in the population. —Economic density is the ratio between the requirements of (ii) Stationary population is a population, which has equal birth population and the resources made available to it by and death rates, so population shows zero population growth. population in the areas it occupies. (iii) Declining population is a population, which has higher death —Room density is most commonly used in urban studies. It is rate than birth rate, so the population has more numbers of older individuals. the average number of people per room in a given area. 72 Magbook ~ Geography–India and World Population Growth Factors Affecting Population Growth — Change in population can be measured both in terms Birth Rate of absolute numbers and in percentage. — Demographic Structure Regions with a high proportion of adults — The natural rate of growth of population is the ratio of will tend to have high birth rates. the difference between births and deaths by — Education With education come knowledge of birth control, population to the total population at the beginning of greater social awareness and a wider choice of action. the period and multiplying it with hundred. — Religion Many of the world’s religions, like the Muslim and — The negative rates of natural increase results from an Roman Catholic, encourage large families in order to safeguard excess of deaths over births. Positive rates of natural the continuance of their beliefs. Some, actively oppose any increase results from an excess of births over deaths. form of contraception. — Basic components of population growth are fertility, — Social Customs In some places, polygamy is practiced and this mortality and migration. These three components are adds greatly to levels of fertility. Certain cultures attach great precisely measured to calculate the magnitude of importance to a male heir, so that large families are common in change in population. the hope of male child or in order to ensure the survival of at Fertility least one boy. — Diets and Health The poorest and most under-nourished people — Fertility refers to the occurrence of birth. It of the world tend to have the highest birth rates. is different from fecundity, which refers to reproductive capacity of women during her entire Death Rate reproductive period. — Demographic Structure Countries where there is a high — Crude Birth Rate (CBR) is the number of live births proportion of aged people will have generally high death rates. on per thousand births in a year. — Health and Medical Services The better medical services and During a year supplies, the lower will be the death rates. = × 1000 Population (mid - year) — Social Class Poorer sections of population usually have higher — It is the simplest measure of fertility which is death rates than do richer sections. expressed in terms of number of live births in a year — Occupations Certain occupations are more dangerous than per 1000 of mid-year population. It bringing out exact others and therefore, lead to a greater number of deaths. rate at which the population increases through birth. — Fertility Ratio (FR) is expressed in terms of children World Population Prospects 2019 below 5 years of age per 1000 females of The World Population Prospectus : The 2019 Revision, reproductive age group. published by UN Department of Economic and Social Population of children below 5 years Affairs, provides a comprehensive review of global FR = × 1000 Female population between 15 to 49 years demographic trends and prospects for the future. The current world population of 7.8 billion is expected to Mortality reach 8.6 billion in 2030, 9.8 billion in 2050 and 11.2 billion — Mortality refers to the occurrence of death. Crude in 2100 according to United Nations report. Death Rate (CDR) is the ratio between the number of deaths in a single year and the total population and is expressed as a number per thousand. Theories on Population Growth — In order to explain the nature of population growth and the Infant and Child Mortality Rate relationship between population and resources, many theories — Infant Mortality Rate (IMR) measures the probability have been proposed, which are as follows: of death in the first year of life, are the sum of neonatal mortality rate (from birth to age 28 days) Malthusian Theory and post- neonatal mortality rate (from 1 to 11 — According to Thomas Malthus, a British demographer, there was months of age). a finite optimum population size in relation to food supply and that an increase in population beyond that point; would lead to a — Child Mortality Rate (CMR) or Under-5 Mortality Rate decline in living standards and to war, famine and disease. His (U5MR) refers to deaths from birth up to a child’s 5th theory was based on two principles: birthday. Each rate is calculated as the number of (i) Human population, if unchecked, grows at a geometric or exponential deaths in the specific age group per 1000 live births. rate. e.g. a U5MR of 150 indicates that there are 150 i.e. 1 —> 2 —> 4 —> 8 —> 16 —> 32 etc. deaths before the 5th birthday for every 1000 live (ii) Food supply, at best, only increases at an arithmetic rate. births or that 15% of children die before age 5. i.e. 1 —>2 —>3 —>4 —>5 etc. Magbook ~ Human Geography 73 — Malthus considered that this must be so because — Third Stage This is the stage of declining population growth. yields from a given field could not go on increasing Due to spread of education, consciousness about the small forever and the amount of land available is finite. The families and development in the social and economic positive and preventive checks which occur in human structure, the birth rate declines alongwith the death rate. populations to prevent excessive growth relate to This stage is evident in Eastern Europe, Central Asia and practices affecting mortality and fertility respectively. China etc. India has also entered into this stage, since 1991. — According to him, Preventive (or negati