Unit - III Natural Resources.ppt
- 1. Unit – III Natural Resources
- 2. Resources 2 Any thing which is useful for man or can be transformed into a useful product or can be used to produce a useful thing. Natural Resources Its defined as anything that we get from the environment to fullfill our requirments and used without any modification. Ex: air ,water, land ,forest, minerals.
- 3. Classification of natural environment 3 1. On the basis renewability Non –Renewable /stock resources . Ex: Minerals, coal, oil, natural gases. Renewable /Flow Resources. Ex: solar energy of the sun, oxygen in air ,soil in forest . Fig.4 Classification on the basisof renewability Cyclic Ex: Water can be regenerated by water cycle
- 4. 2. On the basis of utility 4 Fig .5: On the basis of utility 3. On the basisof origin Energy Ex . Solar Energy Fossil Fuels Raw Material Ex. Iron, Sillca ,Diamond ,Vegetable . Biotic Ex. Green plants , Animals, Fungi etc. Abiotic Ex .Land , Water , Air. Fig.6: On the basis of origin
- 5. Natural Resources and Associated Problem 5 The Natural Resources are as follows : 1.Forest Resources. 2.Water Resources. 3.Mineral Resources. 4.Energy Resources . 5.Land /Soil Resources.
- 6. Forest Resources 6 Problems Soil erosion ,loss of biodiversity , global warming , Floods, Drought. Causes Deforestation and exessive use of forests , increased population. Solution Reserve forests by saving trees ,more plantation, cantrol birth rates to control over population.
- 7. Functions of forests 7 1. Protective function : protect against soil erosion, floods, drought, noise, radiation. 2. Productive function: provide gum resins, medicine, kattha , honey, pulp, bamboo, timber and fruits. 3. Regulative function : regulate level of oxygen ,carbon dioxide, temperature, and water cycle. 4. Accessory function: regulate aesthetics , habitat for wildlife and place for recreartion .
- 8. Water Resources 8 Water resources are sources of water that are useful or potentially useful to humans. Uses of water include agricultural, industrial, household, recreational and environmental activities. Virtually all of these human uses require fresh water. Water forms 60% of our body weight. Water is a renewable and limiting resource.
- 9. About three – fourth of earth’s surface is occupied by oceans. About 97% of the earth’s water is strong saline and The rest 3% is freshwater. Pure, usable water on land is only 0.3%. WATER DEPLETION It is caused by over exploitation, excessive use and unequal access to water among different social groups. 9
- 10. Increasing population, intensive industrialization, deforestation and mismanagement of water resources have caused a crisis. Conservation of Water It is essential for the survival of mankind, plants and animals. This can be achieved by adopting the following methods: Constructing dams and reservoirs to regulate supply of water to the fields, as well as to enable generating hydroelectricity. 10
- 11. Sewage should be treated and only the clear water should be released into the rivers. Industrial wastes (effluents) should be treated to prevent chemical and thermal pollution of fresh water. Judicious use of water in our day-to-day life. Rainwater harvesting should be done by storing rainwater and recharging groundwater. 11
- 12. MINERALS RESOURCES Minerals are naturally occurring, inorganic, crystalline solids having a definite crystalline solids having a definite chemical composition and characteristic . physical properties. Minerals are exhaustible and nonrenewable. Minerals are relatively plentiful. Minerals are over used by industries. Disposal of minerals have negative effects on environment. Metallic minerals – e.g., iron, copper, silver, gold. Non-metallic minerals – e.g., sand, stone salt, phosphates. 12
- 13. Use of Minerals 13 • The main uses of minerals areas follows: • Developmentof industrial plants and machinery. • Generation of energye.g. coal, lignite, uranium. • Construction, housing, settlements. • Defenceequipmentweapons, armaments. • Transportation means.
- 14. Soil Resources 14 Arable land (from Latin arabilis, "able to be plowed”)is land capable of being ploughed and used to grow crops. Land is among the most important natural resources. It covers up only 29% of the earth’s surface and all parts of the land are not habitable. The uneven distribution of population indifferent parts of the world is mainly due to varied characteristics of land and climate.
- 15. • Land degradation means: 1)Loss of natural fertility of soil because of loss of nutrients. 2)Less vegetation cover. 3)Changes in the characteristic of soil. 4)Pollution of water resources from the contamination of soil through which water. 5)sweeps into ground or runoff to the water bodies. 6)Changes in climatic conditions because of unbalance created in the environment. 15
- 16. Causes of land degradation 16 Deforestation. Soil erosion by wind or water. Rainfall. Industrialization. Unsustainable Urban agricultural practices expansion. Biotic Factor.