PRIMARY ACTIVITY – I
- Mining is an important primary activity. It supports the industrial growth of a country.
- Mining is the extraction of valuable minerals or other geological materials from the Earth.
- Mining of stone and metal has been an important activity from prehistoric times.
- Early humans used minerals to make crude implements and weapons.
- Today, mining is carried on a very large scale since industries use minerals extensively.
- Minerals are non – renewable resources.
- Mining, therefore, is known as a Robber industry because the extracted materials cannot be replaced.
Classification of Minerals
- Minerals are classified based on their mineral content and used as metallic minerals, non – metallic minerals and power minerals.
- Metallic Minerals like iron ore contain metals while no metallic minerals like limestone do not contain metals.
- Power minerals are non-metallic minerals which are very important fuel resources.
|Metallic||Non – metallic||Power Mineral|
- A mineral may occur in pure from or maybe mixed with other materials of the rocks as ores.
- The Ores are mined and then refined to extract valuable elements
- Minerals ores may occur in cracks, faults or joints of rocks or as sediments.
- Mineral ore deposits are thus classified as occurring in veins, lodes, beds and alluvial deposits.
Types of Mining
- There are different methods of mining to extract minerals.
- Mining may be on the surface or subsurface (underground) depending on the occurrence of minerals
- Surface mining methods include open cast mining, strip mining and alluvial mining.
- It is used to mine the minerals that are found closer to the surface.
- Opencast mining involves the digging out of minerals that occur on the surface of the Earth.
- Strip mining removes long strips of overlying soil and rock.
- Alluvial mining is used to exact minerals by panning or dredging minerals like tin and gold which are sometimes mixed with alluvium in the river bed.
- Quarrying is the mining of building materials like limestone from the Earth‘s surface.
- In Underground Mining, ores are extracted from greater depths beneath the surface.
- Underground mining usually more expensive than surface mining. Safety precautions are very important in underground mining.
- For example, coal mines are often prone to catch fire because of the gases trapped underground.
- Drilling is a mining method used to extract minerals like oil and natural gas. Oil rigs are used for drilling oil wells.
- The most familiar sights in the oil fields are the tower-like features or derricks which mark the places where the oil is being drilled.
DISTRIBUTION OF MINERALS
Metallic minerals Iron Ore
- Magnetite, hematite, limonite and siderite are different types of iron ore, according to the iron content of the ore.
- Iron ore mines are found extensively in U.S.A Canada, Australia, China, Brazil, India and Kazakhstan.
- It is mined from open pits. Large copper mines are found in Utah in USA, Mexico, Zambia, Chile and Indonesia.
- Bauxite is the ore of aluminium. Bauxite is extracted from open-pit mines.
- Australia, Brazil, Jamaica and Guinea have large reserves of bauxite.
- Ore is called cassiterite. The ore is obtained by alluvial mining.
- Tin is mined in Malaysia, Bolivia, Indonesia, China, Russia, Nigeria and Congo.
- Gold is a precious metal that is extracted through the placer or alluvial method.
- Carat is the term used for the purity of the gold.
- The largest producers are South Africa, Canada, USA, Australia and Ghana.
Non – Metallic Minerals
- Salt, Potash, nitrates, Sulphur, mica, rock salt and phosphates are non – metallic minerals.
- Rubies and diamonds are also classified as non – metallic.
- It is extracted through underground mining.
- It is a bright yellow mineral.
- Heavy chemical Industries require sulphur to produce chemical products.
- The USA, Mexico, Italy and Japan are large producers.
- Mica is a black, transparent matter that splits easily into thin sheets.
- Mica is used in electrical industries.
- The USA, India, Norway, Brazil and Russia are important producers.
- Generally extracted from open-pit mines.
- It is used to make fire proof materials.
- It is mined in Canada, Russia, Brazil, South Africa, Rhodesia, China, USA and Italy.
- The three major sources of Power resources are coal, oil and natural gas.
- These non – renewable minerals have been discussed in an earlier lesson.
PRIMARY ACTIVITY – II
- The Earliest human civilizations developed in large river valleys.
- Agriculture is the key development that led to the rise of these civilizations.
- Agriculture is an important primary activity. Her, humans do not merely collect from nature but work with nature to produce their food.
- Agriculture includes not only the growing of crops and trees but may also include the domestication of animals.
- Agriculture includes preparation of land, seeding, irrigation, development of hybrid varieties in order to grow food to support large populations.
|Indus||Harappa and Mohenjo-Daro||Asia|
- Agricultural crops can be broadly grouped into food and cash crops.
- Cash crops are not consumed as food but are used as raw materials for further processing (For example rubber, Cinchona and cotton).
- Food Crops May be grown as subsistence crops or as commercial crops.
Geographical Factors that determine Agriculture
- Major factors that affect Agricultural diversity and distribution are climate, landforms, soils, availability of water and labour.
- Climatic factors like temperature and rainfall affect agriculture.
- Most plants cannot grow if the temperature falls below 60 C as the soil gets frozen.
- Different crops are grown in different climate regions.
- For example, rice is the principal crop of the tropical region as it requires high temperature and plenty of water.
- Wheat is a temperate crop which grows in the cool climate.
- Altitude affects the temperature and so it also affects agriculture.
- In the High altitude areas of tropical regions, temperate crops like carrots can be grown.
- Growing seasons vary from crop to crop. Some crops like cotton require 200 frost-free days for their optimum growth and so are grown in the warmer seasons.
- Moisture availability determines the type of crop and the growing season. The seasonality of rainfall is important.
- Crops require adequate rain for their growth but the timing of the rain affects crops differently.
- Seasonal variation of rainfall is important as different crops require water at different times.
- For example, coffee must have dry conditions before and during harvest while maize needs water in the same season.
- The amount of rainfall determines the types of crops grown in an area.
- Rice is grown wherever the rainfall is abundant, while millets are grown in the drier regions.
- Uni or mono-cropping – only one crop is raised in the field at one time.
- Multiple cropping is the practice of growing two or more crops in the same field during a single growing season.
- For example, in the Garhwal Himalayas, 12 or more crops are grown on the same plot, including various types of beans, grams and millets and harvested at different times.
- Where rainfall is inadequate or unreliable, irrigation is necessary for agriculture.
Types of Irrigation
- Ditch irrigation is one in which water distributed to the fields through canals.
- Sprinkler irrigation sprays water through sprinklers located in the field.
- Central pivot irrigation the circular area around a pivot is irrigated, often creating a circular pattern in crops when viewed from above.
- Drip Irrigation which water is delivered at or near the root zone of plants, drop by drop.
- The major relief features are mountains, plateaus and plains. Among them, the plains with fertile soils and level lands make agriculture possible.
- The most intensively cultivated areas of the world are the lowlands.
- For example, the plains of North India are best suited for agriculture.
- On mountain slopes, agriculture is limited by the availability of level land.
- The hill slopes are however ideal for crops like tea and coffee which require well-drained slopes where the water will not stagnate.
- Soils influence crop cultivation because different crops prefer different soils.
- Alluvial soils are the most fertile and ideal for agriculture since they are replenished constantly.
- Other fertile soils that are used extensively for agriculture include volcanic soils and grassland soils.
- Besides geographical factor, social and economic factors influence the type of agriculture which is practised by different groups of people.
Types of Agriculture
- Agricultural types include shifting agriculture, subsistence farming, intensive subsistence farming, commercial agriculture, extensive mechanized farming and mixed farming.
- The type of agriculture refers to the nature of the organization of agricultural operations and crop types.
- In this type of farming, the farmers grow just enough food for themselves and their families.
- Subsistence agriculture may be of two types-simple subsistence agriculture and intensive subsistence agriculture.
- Simple subsistence farming is practised by small tribal groups and is also called shifting agriculture.
- The farmers clear small parts of the forest by cutting and burning the trees and grow simple crops like millets and yam.
- After a few years, they abandon the farms and move to another part of the forest and repeat the same process
- Shifting agriculture is called by different names in different parts of the world-Roco in Brazil, Jhum, Bewar and Poda in India, Milpa in Central America and so on.
- Intensive subsistence farming is found in the densely populated monsoon lands of Asia.
- Rice is the dominant crop, Farms are very small and the farmers cultivate it intensively using manure, high yielding varieties of seeds, family labour and the land is never left fallow. Crop yield is very high.
- This type of farming is also called extensive farming.
- In this type of farming, crops are raised on a very large scale and faring is mechanized.
- Wheat is the dominant crop and yield is low commercial farming is common in North America and Argentina in South America.
- The plantation is very large farms in tropical areas which involve heavy capital and focus on crops like tea, coffee and rubber.
- These are usually perennial crops where are crops yields for many years.
- Plantations are found in Sri Lanka, Malaysia, India, Indonesia etc.,
- This is a special type of farming found in the well – developed parts of the world in which crops, as well as livestock, are raised.
- Such farms are common in Western Europe.
PRIMARY ACTIVITY – III
- A range of crops is grown by human – some for food and others for fibre.
- Cereals are grass-like plants which have starchy, edible seeds.
- The most common cereals are rich, wheat, Maize and millets.
- Rice is an important staple food for a large part of the human population, especially in Asia and Latin America.
- Rice is a tropical crop which grows well in alluvial plains and river deltas.
- The parent’s species of rice are native to South Asia.
- Rice was first domesticated in the Yangtze River valley of China.
Conditions for the growth of rice
- Rice requires an average temperature of 240 C and an average rainfall of 150 cm. Where rainfall is inadequate, the crop has to be irrigated.
- Rice requires a level surface because it is grown in standing water.
- Upland areas are terraced and levelled to create lowland and flooded condition.
- Rice can be cultivated thrice in a year in the river deltas.
- Alluvial soils are best suited for rice cultivation because of their high fertility.
- Rice is a labour-intensive crop since the preparation of the field, sowing, transplanting, weeding and harvesting are done by hand.
- Asia is the largest producer of rice.
- Asian farmers account for 98 % of the world‘s rice producers.
- China, India, Indonesia and Bangladesh are the top 4 producers of rice In India, rice is grown extensively in all the major river valleys.
- Wheat is a temperate crop and it is an essential part of the diet of the temperate regions.
- About 25 % of the world‘s farmland is devoted to wheat cultivation.
Conditions for the growth of wheat
- Wheat requires warm and moist conditions in the early stages of growth and dry sunny conditions in the later stages.
- Temperatures of 150C – 200 C is ideal for wheat growth.
- It requires an average rainfall of 50 – 60 cm.
- It grows best in clayey or loamy soils.
- The world‘s best wheat comes from the soils of the temperate grasslands due to large amounts of organic matter in the soil.
- Wheat cultivation is highly mechanized and requires open undulating topography
- The world‘s greatest wheat-producing areas are USA, China, Ukraine, Canada, Argentina, Australia, India and Pakistan.
- In India, U.P, Punjab and Haryana and the Major wheat-producing states
- Fibre crops include cotton, jute and flax.
- Cotton is a shrub native to tropical and sub – tropical regions.
- The soft fluffy fibre grows in a ball around the seeds of the cotton plant.
- The Seeds are removed from the fibre by means of a process called ginning.
Conditions for the growth of cotton
- Cotton grows well in areas having a temperature between 20 – 300 C and rainfall of 50 – 100 cm.
- Black soils and alluvial soils are best suited for cotton cultivation.
- It requires cheap and skilled labour, especially for handpicking cotton bolls.
- Cotton is harvested mechanically in some parts of the world.
- The leading producers of cotton are the USA, Uzbekistan, Brazil and Pakistan.
- In India, cotton producing states include Maharashtra, Gujarat, Tamil Nadu, Karnataka and Madhya Pradesh.
- Andhra Pradesh, Punjab and Haryana and parts of Rajasthan.
- Jute is a long soft shiny vegetable fibre which can be spun into coarse strong threads.
- jute is used for making jute bags, carpets and yarns.
Conditions for the growth of Jute
- Jute requires a high temperature of 300 C and rainfall of more than 150 cm.
- Well-drained fertile alluvial soils are ideal for the cultivation of jute.
- Cheap labour is required to obtain the fibre by retting the plant.
- Retting is a microbiological process in which the plant is soaked in water for 2 – 3 weeks to soften the outer bark after which the fibre is removed
- India and Bangladesh are the major producers of jute.
- Sugarcane is a tall tropical grass which grows to a height of 3.5 m.
- It is cultivated almost everywhere in the tropics and the subtropics.
Conditions for the growth of sugarcane
- Sugarcane requires a hot climate with an average temperature of 240 C throughout the year.
- It requires about 130 cm of rainfall and deep, well-drained fertile soils.
- It requires a large supply of cheap labour, especially during harvest.
- Latin America and Southern and Eastern Asia are the main producing regions.
- India, Pakistan, Indonesia and Brazil are other important producers.
- Tea is a beverage made from the leaves of a tropical shrub. Tea is a hardy perennial shrub.
- The plant is constantly trimmed to a height of 1.5m. to stimulate the growth of new leaves and to facilitate the picking of the leaves
Conditions for the growth of Tea
- Tea is cultivated on the hill slopes of the tropics and the subtropics.
- It requires an average temperature of 210 C and rainfall of 150 cm for its growth Severe frosts damage the crop.
- Tea requires well-drained soils.
- Tea can withstand heavy winds and sunshine and hence grown in windward slopes of the hills.
- It is a labour-intensive crop.
- China, India and Sri Lanka are the major producers of tea.
- In India tea is grown in Assam, West Bengal, Kerala and Tamil Nadu.
- With the advancement in science and technology, humans started to process natural resources of the Earth, Including agricultural crops to make a new product for his use.
- These activities of man are called as secondary activities.
- This will be dealt with in the following chapters.