Geography Class 08 NCERT

1. Resources - original form has changed. Technology is a human made resource.
1. Human - number and abilities of people. Transforms physical materials into a valuable resource.
2. Sustainable development - carefully utilizing resources so that meeting requirements of the present and taking care of the future generations.
2. Land, soil, water
1. Land
1. Land covers about 30% of total earth's surface (99% population occupies 30% of land area).
2. Land degradation, landslides, erosion, desertification are major threats to environment because of expansion of agriculture and construction.
3. Landslides are defined as mass movement of rock, debris, or earth down a slope;
4. often accompanied with earthquakes, floods, and volcanoes.
2. Soil - thin layer of grainy substance covering surface of earth. Closely linked to earth as landforms determine type of soil.
1. Soil is made up of organic matter, minerals and weathered rocks found on earth.
2. Major factors of soil formation - parent rock & climatic factors.
3. Indian soil types - alluvial, black, red, laterite, desertic and mountain soil.
4. Methods of soil conservation
1. Mulching - covering bare ground with organic material such as straw; helps retaining soil moisture.
2. Contour barriers - using stones, grass, soil to build barriers along contours.
3. Rock dam - rocks piled up to slow down flow of water; prevents gullies and further soil loss
4. Terrace farming - flat steps on steep slopes to grow crops on flat steps; reduce surface run off and soil erosion.
5. Intercropping - different crops in alternate rows and sown at different times
6. Contour ploughing & shelter belts (protect soil cover from winds)
3. Water in primitive oceans life began on earth 3.5 billion (earth is almost 4-4.5 billion years old) years back. Water can neither be added nor subtracted from earth.
3. Vegetation major vegetation types of the world - forests, grasslands, scrubs and tundra - depends on temperature and moisture.
4. Deciduous forests shed their leaves in a particular season to conserve loss of moisture through transpiration.
5. Natural parks
1. natural area designated to protect the ecological integrity of one or more ecosystems for the present and future generations
6. Biosphere reserves
1. series of protected areas linked through a global network, intended to demonstrate the relationship b/w conservation and development.
7. Minerals - naturally occurring substance with definite chemical composition.
1. Not evenly distributed, created without human interference.
2. Rock is an aggregate of one or more minerals but without definite composition of constituent of minerals. Rocks from which minerals are mined are known as ores.
3. Switzerland has no known mineral deposit.
4. Minerals - metallic (ferrous and non-ferrous) and non-metallic
1. Metallic - contain metals which conduct heat and electricity.
• Metallic minerals found in igneous and metamorphic rocks formations in large plateaus.
• Iron ore, bauxite, manganese ore.
• Non-ferrous contain non-iron metals such as gold, silver, copper, lead.
2. Non-metallic - do not contain metals.
• Limestone, mica, gypsum, coal, petroleum.
• Non-metallic minerals are in sedimentary rock formations of plains and young fold mountains.
5. Extraction of minerals
1. mining (open cast is removing surface, shaft uses deep bores),
2. drilling (deep wells are bored),
3. quarrying (simply dug from surface).
6. Minerals deposits
1. Rocks containing copper look blue in color.
2. Green diamond is rarest.
3. Nickel, zinc, copper is found almost everywhere.
1. Asia - China & India have large iron ore deposits, 50% of tin. Manganese, bauxite.
2. Europe - leading producer of iron-ore - Russia, Sweden, France. Lead, manganese.
3. North America - Canadian Shield (iron ore, gold, uranium), Appalachian region (coal) and Rockies. Western Cordilleras have vast deposits of lead, gold, silver.
4. South America - Brazil largest producer of high grade iron ore.
• Chile & Peru - leading in copper. Brazil & Bolivia - leading in tin.
• Continent also have - gold silver, manganese, bauxite, mica, platinum, diamond. +Mineral oil.
5. Africa - world's largest producer of diamonds, gold, platinum.
• South Africa, Zimbabwe, Zaire - world's gold.
6. Australia - Largest producer of bauxite (not a mineral, ore for aluminum).
• Oldest rock in western Australia 4.3b years ago.
7. Antarctica - variety of mineral deposits: coal, iron ore, gold, silver.
• Antarctic Treaty System regulates international relations wrt Antarctica.
• All land forms south of 60 degree latitude. Signed by 12 parties in 1959, effective 1961, currently 53 signatories,
• HQ - Buenos Aires.
• Sets aside Antarctica as a scientific preserve, establishes freedom of scientific investigation and bans military activity on that continent.
• Convention on the Regulation of Antarctic Mineral Resource Activities - prohibits mining on the continent
7. Distribution in India
• Iron, Bauxite, Mica (largest producer), Copper, Manganese, Gold (Kolar, deepest in world), salt (source - seas, lakes, rock)
8. Conventional sources of energy - Firewood (still heavily used in India for cooking) and fossil fuels.
1. Types of fossil fuels
1. Coal - most abundant.
• Used as a domestic fuel, industries and electricity generation.
• Also called buried sunshine.
• China top producer.
2. Petroleum - found between layers of rock, refined to produce variety of products,
1. called black gold.
2. USA is top producer for crude annually since OPEC went for production cuts.
3. Natural gas - found with petroleum deposits,
1. released when crude oil brought to surface.
2. US/Russia top producers. US thanks to shale gas and hydraulic fracturing.
2. Other conventional sources
1. Hydel - Norway was 1st country to develop hydroelectricity.
2. China is top producer with Brazil in 2nd.
3. India 14% of total power generation capacity is hydel.
9. Non-conventional
1. Solar - prepare in detail
2. Wind - prepare in detail
3. Nuclear - obtained from nuclei of atoms of naturally occurring radioactive elements like uranium and thorium, these undergo fission in nuclear reactors.
• Indian coast has thorium in monazite sands (AP largest, mined by Indian Rare Earths Ltd under DAE).
• Reactors are in Kalpakkam, Tarapur, Narora, Kaiga
4. Geothermal - heat energy from earth in form of hot springs
• Manikaran and Puga Valley in Ladakh.
5. Tidal - France built first tidal station.
• During high tide, energy of tides used to turn the turbine installed.
6. Biogas - organic waste such as dead plant and animal material can be converted into biogas.
• Organic waste is decomposed by bacteria in biogas digesters to emit biogas which is basically methane and carbon dioxide.
• Hydrogen sulfide is main sewage gas.
10. Agriculture
1. 3 types of economic activities -
1. Primary - connected with extraction and production of natural resources
2. Secondary - processing of these resources
3. Tertiary - support to primary and secondary
2. Agriculture - raising crops and rearing livestock,
1. sericulture - rearing of silk worms,
2. pisci culture - breeding of fishing in artificial ecosystem,
3. viticulture - cultivation of grape,
4. horticulture - growing vegetables, flowers and fruits
3. India's agricultural land 60%, arable 53%.
1. Organic farming - organic manure and natural pesticides are used, no genetic modification is done to increase crop yield.
2. Types of farming
1. Subsistence farming - practiced to meet needs of family, low level of tech and household labor.
2. Intensive (depend on monsoon, rice/wheat main crop) and primitive (shifting - in areas of heavy rainfall and quick regeneration of vegetation with crops like maize, yam, potatoes, cassava, & nomadic herding - in arid and semi-arid regions).
3. Shifting cultivation names
1. Jhumming (NE India),
2. Milp (Mexico),
3. Roca (Brazil),
4. Ladang (Malaysia).
4. Commercial farming - crops are grown and animals reared for sale in market, practiced in North America, Europe and Asia.
1. Plantation - large amount of capital and labor, usually in tropical regions.
4. Major crops -
1. Rice - major crop of the world, staple diet of tropical and sub-tropical regions.
1. Needs high temperature,
2. high humidity and rainfall.
3. Grows best in alluvial clayey soil which can retain water.
2. Wheat - requires moderate temperature and rainfall during growing season.
1. bright sunshine at the time of harvest.
2. Best in well drained loamy soil.
3. Millets - coarse grains (Jowar, bajra, ragi in India. Nigeria, China, Niger.)
1. can be grown on less fertile and sandy soils,
2. needs low rainfall
3. moderate high temperature.
4. Maize (corn) - requires moderate temperature,
1. rainfall and lots of sunshine.
2. Needs well drained fertile soils. North America, Brazil, China.
5. Cotton
1. requires high temperature,
2. light rainfall
3. 210 frost free days and bright sunshine.
4. Best on black and alluvial soil. China, USA, India
6. Jute - golden fiber.
1. Alluvial soil and high temperature,
2. heavy rainfall and humid climate.
3. Grown in tropical areas. India and Bangladesh.
7. Coffee - (discovered in Arabia around 850 AD, goats were feeding on it)
1. warm and wet climate
2. well drained loamy soil.
3. Hill slopes more suitable. Brazil, Colombia, India.
8. Tea - cool climate and high rainfall throughout the year.
1. Well drained loamy soil
2. gentle slopes plus high labor. Kenya, India, China, SL.
11. Industries - refers to an economic activity that is concerned with production of goods, extraction of minerals or provision of services.
1. Classification on the basis of:
1. Raw materials - agro based, mineral based, marine based, forest based
2. Size - cottage, small, medium, large scale
3. Ownership - public, private, cooperative, state owned
2. Iron and steel industry
1. iron ore + limestone + coke (blast furnace) = molten iron + slag.
2. 8 coal :4 iron ore :1 limestone =1 steel. (Smelting - process in which metals are extracted from their ores by heating beyond melting point).
3. Steel is back bone of modern industry. India is at 90 million tons in 2016.
3. Cotton textile - man-made fibers are nylon, polyester, acrylic, rayon.
1. First textile mill in country at Fort Gloster, Kolkata 1918.
2. flourished in Maha & Guj because of humid climate.
12. Ministry of Human Resource Development (now change in M/o education)
1. created in 1985.
2. More than 90% population stays in 10% of land surface.
3. Avg density of population in India - 382 persons per sq km.
4. Factors affecting distribution of population
1. topography,
2. climate,
3. soil,
4. water,
5. minerals ,
6. socio-c ultural and economical.