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UNIT – 2 NATURAL RESOURCES. Contents. Classification of Natural Resources. Water Resources. Mineral Resources. Energy Resources. Land Resources. NATURAL RESOURCES. Natural resources are naturally occurring substances that are considered valuable in their relatively natural form.
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Contents Classification of Natural Resources Water Resources Mineral Resources Energy Resources Land Resources
NATURAL RESOURCES Natural resourcesare naturally occurring substances that are considered valuable in their relatively natural form. Air we breathe, Water to drink Land to live Food for growth
On the basis of origin, the natural resources Living Resources: All Living Natural resources like birds, animals Non – Living Resources: All non-living resources like ocean full of water, wind energy, sun, metals like iron, aluminium, gold, etc. Classification of Resources
Based on the availability, natural resources are divided into (a) Inexhaustible Resources Present in unlimited quantities on earth Eg: Water, wind, sun (b) Exhaustible Resources Present in limited quantities. Coal, oil ,gas
Renewable & Non-renewable Resources On the basis of Replenishability: Renewable : Resources have the ability to reappear or replenish themselves by recycling, reproduction or replacement. E.g.: Oxygen in air is replenished through photosynthesis. Fresh water is replenished through water cycles. Biological products include wild life and natural vegetation of all kinds. They are replenished through natural cycles of growth and reproduction.
Non-renewable Resources It exists in a fixed amount that cannot be re-made, re-grown or regenerated as fast as it is consumed and used up. Often fossil fuels, such as coal, petroleum natural gas , and Gold
WATER RESOURCES Introduction Use and over utilization of surface and ground water FLOODS DROUGHT Dams: Benefits & problems
Introduction • The economy, agriculture and industrial growth of mankind is largely dependent on water resources • Infact, ancient civilizations flourished along perennial surface water like streams and rivers SNIST/Biotech/Ravindra/ES-2Company Logo
Distribution of Water 90% of the earth is covered by water Of the total water available Oceans and salt lakes 97.6% Freshwater constitute 2.4% If we look at freshwater alone Trapped in ice and snow 87% Available as liquid water 13% Of the total available liquid water (13%) Groundwater constitutes 95% Lakes, rivers and streams 03% Soil moisture 02% Therefore, only about 0.1% of the world’s freshwater is accessible 11 11 SNIST/Biotech/Ravindra/ES-2Company Logo
Use and Overuse • Water is a vital natural resource which forms the basis of all life. • Water is needed to fulfill diverse Domestic requirements. • Aquaculture has come up as a very potent industry. • For generation of Hydroelectric Power. • In industrial processes viz., a raw material, solvent, chemical reactant, coolant, and cleaning agent. SNIST/Biotech/Ravindra/ES-2Company Logo
Use of Fresh Water SNIST/Biotech/Ravindra/ES-2Company Logo
Hydrological Cycle 15 15 SNIST/Biotech/Ravindra/ES-2Company Logo
Ground Water: • Groundwater is the source of about 90% country's drinking water. • In rural areas, groundwater is the only source for water and more than one-third of our 100 largest cities depend on it. • Rain water move downward and get stopped when the water meets rock that has no porosity. • A layer of sediment or rock that is highly permeable (porous) and contains water is called an aquifer. • This causes saturation of water in the soil and the zone is called saturation zone. • The upper boundary of the zone of saturation is called the water table.
However, groundwater is becoming contaminated with industrial effluents discharged on land and septic systems, as well as illegal and uncontrolled hazardous waste sites. • Once contaminated, groundwater is difficult, if not impossible, to restore.
Over utilization Groundwater • Groundwater abstraction from aquifers faster than natural recharge causes a ‘cone of depression’ in the water table • This may dry up nearby wells • Over utilization also allows aquifers to collapse followed by sinking of the groundwater surface • Overuse of freshwater allows salt water intrusion into aquifers used for domestic and agricultural purposes in coastal areas
Surface Water: • Surface waters are available as a result of precipitation. • Precipitation that doesn't seep into the ground or does not return to the atmosphere by evaporation or transpiration is called surface water. • Rain drops and snow flakes reach to surface of the earth • It forms streams, ponds, ocean, lakes, wetlands and artificial reservoirs
In china it takes 1000 tonnes of water to produce one tonne of wheat. • water required to grow a tonne of grain = manufacture a tonne of most industrial materials (e.g., metals or plastics, etc.). • World water council believes that by 2020, we shall need 17% more water than is available to feed the world.
Floods occur when water from heavy rainfall, melting ice or snow, tsunamis or a combination of these, exceeds the carrying capacity of the receiving river system. It is a natural process FLOODS
Floods occur when soil and vegetation cannot absorb all the water; water then runs off the land in quantities that cannot be carried in river channels or retained in natural ponds and constructed reservoirs held behind dams.
Failure of levees and dams and inadequate drainage in urban areas can also result in flooding. Floods damage property, cause soil erosion and endanger the lives
Flooding may deposit as much as 0.4 inches (1 cm) of sediment a year on a flood plain • Floods throughout Asia in 1998 killed 7,000 people, damaged more than 6 million houses and destroyed 25 million hectares of cropland in Bangladesh, China, India and Vietnam • In 2005, the remarkable flooding by Hurricane Katrina, caused more than $200 billion in losses, constituted the costliest natural disaster in U.S. history
Flood Control Measures Reforestation Construction of dams, reservoirs, and floodways (artificial channels that divert floodwater) Defenses such as levees, bunds, reservoirs, and weirs are used to prevent rivers from bursting their banks
‘Deficiency of rainfall over a period of time, resulting in a water shortage for some activity, group or environmental sector’ ‘Dryness due to a deficiency of precipitation and is related to the climatic conditions in a specific environment’ DROUGHT
EFFECTS OF DROUGHT Economic impacts • Lower crop yields, • Spend on irrigation, • Digging wells, • loss of livestock Environmental impacts • Forest fires, • Soil erosion, • Loss of habitat • Loss of endangered species
Social impacts • Conflicts between people • Mental and physical stress on people due to economic losses • Health problems related to low water flows • Threat to public safety from an increased number of forest and range fires • Reduced incomes • Population migrations from rural to urban areas • Fewer recreational activities • Loss of Human life SNIST/Biotech/Ravindra/ES-2Company Logo
DAMS – Benefits and problems Dam is the barrier constructed across a stream or river to impound water and raise its level. Dams - Benefits To concentrate the natural fall of a river at a given site; To generate electricity; To direct water from rivers into canals ,irrigation and water-supply systems; To increase river depths for navigational purposes; To control water flow during times of flood and drought; To create artificial lakes for recreational use. The first dam was built about 4000 BC to divert the Nile in Egypt in order to provide a site for the city of Memphis. SNIST/Biotech/Ravindra/ES-2Company Logo
loss of vegetal cover submergence of large area of land (human settlement) soil erosion Resettlement and rehabilitation problem of displaced people. variation in water table and enhanced seismic activities due to pressure of water. Salts left behind by evaporation increase salinity of the river and makes it unusable. The nature and magnitude of the impacts vary with the project locations and the conditions therein. Environmental Impacts of Large dams - Problems SNIST/Biotech/Ravindra/ES-2Company Logo
MINERAL RESOURCES Introduction Use and Over exploitation Environmental effects of extracting and using mineral resources Case studies 31 31 SNIST/Biotech/Ravindra/ES-2Company Logo
Introduction Minerals are naturally occurring chemical elements or compounds, formed through inorganic processes They are exhaustible, non-renewable resources found in the earth's crust More than 3,000 mineral species are known. However, only 200 minerals are put to economic use They are characterized by chemical composition crystalline structure physical properties Minerals are not evenly distributed in the world Therefore, each country is dependent upon other countries for the requirement of certain minerals India has large reserves of iron, manganese, lime stone, dolomite, silica, and mica But it has little reserves of copper, gold, silver, lead and phosphate Even for NPK fertilizers, India is dependent upon foreign countries 32 32 SNIST/Biotech/Ravindra/ES-2Company Logo
Classification of Minerals MINERALS 1. Metals 2. Industrial Minerals 3. Construction Materials The study of minerals is called ‘Mineralogy’ 33 33 SNIST/Biotech/Ravindra/ES-2Company Logo
Precious Metals Gold Silver Platinum I. Metals (b) Steel Metals Iron Nickel Cobalt 34 34 SNIST/Biotech/Ravindra/ES-2Company Logo
(c) Base Metals Copper Lead Tin Zinc (d) Light metals Magnesium Aluminium 35 35 SNIST/Biotech/Ravindra/ES-2Company Logo
(e) Nuclear Metals Uranium Radium Thorium (f) Special Metals Lithium Germanium Arsenic 36 36 SNIST/Biotech/Ravindra/ES-2Company Logo
II. Industrial Minerals Quartz Trona Salt Potash Asbestos Feldspar Sulphur Phosphates 37 37 SNIST/Biotech/Ravindra/ES-2Company Logo
III. Construction Materials Sand Gravel Brick clays Limestone Shale Granite Travertine Marble collectively known as dimension stones 38 38 SNIST/Biotech/Ravindra/ES-2Company Logo
Uses of Minerals Minerals have always been important after their uses were discovered Mineral wealth reveals a country’s economy and their ability to sell or create products For example, The USA became the richest and the mostpowerful nation in the world in even less than 200 years, due to huge mineral and energy resources Minerals have many uses. They are: Gold Gold is mostly used for making ornaments Gold could be hammered into thin sheets that could be made into useable items without fear of breaking or rusting 39 39 SNIST/Biotech/Ravindra/ES-2Company Logo
Table 2.1 Important uses of some of the major metals 40 40 SNIST/Biotech/Ravindra/ES-2Company Logo
Major Minerals of India India has large number of economically useful minerals India also produces 75% of the worlds Mica Coal and lignite: West Bengal, Bihar, Jharkhand, Orissa, M.P, A.P ,TN Uranium (Pitchblende or Uranite ore): Jharkhand, Andhra Pradesh (Nellore, Nalgonda), Meghalaya, Rajasthan (Ajmer). Aluminium (Bauxite ore): Jharkhand, West Bengal, Maharashtra, M.P, Tamilnadu. Iron(haematite and magnetite ore): Jharkhand, Orissa, Bihar, M.P, A.P, Tamilnadu, Karnataka, Maharashtra and Goa. Copper (Copper Pyrites): Rajasthan (Khetri), Bihar, Jharkhand, Karnataka, M.P, West Bengal, Andhra Pradesh and Uttaranchal. Gold Mines: Ramagiri field in Andhra Pradesh, Kolar and Hutti in Karnataka. Diamond belt: Panna diamond field in district of Panna , Chatarpur. And Satna in MP, and some parts of Banda in UP Petroleum deposits are found in Assam and Gujarat, Bombay, Assam, Tripura, Manipur, WB, Punjab, Himachal Pradesh. 41 41 SNIST/Biotech/Ravindra/ES-2Company Logo
Exploitation The ever increasing demand of the limited mineral deposits and over exploitation may exhaust them within a few decades 42 42 SNIST/Biotech/Ravindra/ES-2Company Logo
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Environmental Effects Any civilization could not exist without mining because it is the only way to obtain mineral resources Without mining, for example, we could not have sources for new metals However, mining practiced without critical safeguards can have dangerous effects to individuals and environment Exploration: Drilling & sampling Loss of vegetation Noise pollution Road trailing Habitat loss Mining operations disrupt ecosystems and may destroy the habitat of many species. For instance, about 350 tons of soil, rock and vegetation must be removed from an area to produce only 1 tonne of copper This process destroys the native biodiversity and makes an area vulnerable to land degradation by erosion and pollution 44 44 SNIST/Biotech/Ravindra/ES-2Company Logo
Mining and Milling - Ore extraction, crushing /grinding of ore, chemical concentration of ore. wind borne dust, acid generation from waste rock, heavy metal leaching from acid mine drainage Mining leads to severe water, air and land pollution Many drainage waters from mining areas have high sulfate and iron concentrations When exposed to air, pyrite and ferrous sulphide in coal seams produce sulphuric acid Plants can be seriously affected in areas with waste water contaminated by copper, nickel, lead and zinc mines Such waste discharges may also kill the decomposers and reduce the soil fertility There are also impacts on aquatic life. One recent study found that mine discharges contain selenium, a chemical harmful in high doses accumulates in fish downstream That might also pose a risk to humans who eat the fish 45 45 SNIST/Biotech/Ravindra/ES-2Company Logo
Smelting & and Refining Processing of mineral concentrate by heat or electro-chemical processes Use of toxic chemicals for processing Sulphur dioxide emissions contribute to acid rain Require high energy 46 46 SNIST/Biotech/Ravindra/ES-2Company Logo
Mine Closure Waste dumps Dismantling of buildings Surface water contamination Revegetation failure Wind pollution Improperly disposed fuel drums 47 47 SNIST/Biotech/Ravindra/ES-2Company Logo
CASE STUDIES 1) Jaduguda Uranium Mine, Jharkhand—-exposing local people to radioactive hazards (2)Jharia coal mines, Jharkhand—underground fire leading to land subsidence and forced displacement of people (3) Sukinda chromite mines, Orissa—seeping of hexavalent chromium into river posing serious health hazard, Cr6+ being highly toxic and carcinogenic (4) Kudremukh iron ore mine, Karnataka—causing river pollution and threat to biodiversity (5) East coast Bauxite mine, Orissa—Land encroachment and issue of rehabilitation unsettled (6) North-Eastern Coal Fields, Assam—Very high sulphur- contamination of groundwater 48 48 SNIST/Biotech/Ravindra/ES-2Company Logo
Uranium Mining in Nalgonda Uranium reserves in Jaduguda mines, Jharkhand supplied the yellow cake until 2004 There is a pressing need for mining more uranium to meet the demands of India's nuclear programme Uranium Corporation Of India Limited (UCIL) will invest Rs. 20 billion (US$ 460 million) to open new mines and set up processing plants in Jharkhand, Andhra Pradesh and Meghalaya UCIL proposes to mine uranium from the deposits in Lambapur and Peddagattu villages of Nalgonda district in Andhra Pradesh and a processing unit at about 18 kms at Mallapur The plan is to extract the ore of 11.02 million tons in 20 years. 49 49 SNIST/Biotech/Ravindra/ES-2Company Logo