Natural resources on our environment for student
- 1. UNIT - 2 NATURAL RESOURCES IV SEMESTER ENVIROMENTAL SCIENCE
- 2. INTRODUCTION The natural resources are the materials , which living organisms can take from nature for the sustenance of their life. A resource is anything we can get from our environment in order to meet our needs. Nature provide us different resources in their natural form called natural resources like minerals, biodiversity, water , soil, air, fossil fuels and forests
- 3. CLASSIFICATION OF NATURAL RESOURCES A. Depending upon their chemical composition(nature) the natural resources are of three types: i) Inorganic Resources : They include air, water and ores. ii) Organic Resources: They include plants, animals, microorganisms, fossils fuels. iii) Mixtures of inorganic and organic Resources: They include soil
- 4. B. Depending upon the abundance and availability of the natural resources they are classified into two categories: RENEWABLE RESOURCES: Renewable is defined as a resource that is capable of being replaced by natural ecological recycle. A natural resource is a renewable resource if it is replaced by natural processes at a rate comparable or faster than its rate of consumption by human A renewable resource is something that is being continually replaced faster than we use it up. Example, Solar energy, Wind power, thermal power etc.
- 5. B. Depending upon the abundance and availability of the natural resources they are classified into two categories: NON-RENEWABLE RESOURCES: A non renewable resource is a natural resource that cannot be produced, regrown, regenerated, or used on a scale comparative to its consumption rate. It is something that is not being replaced as we consume it. These resources lack the ability of recycling and replacement Example, Coal, oil , natural gas, etc.
- 6. C. Natural resources are classified on the basis of their Presence in different countries i) National Resources: They are confined to national boundaries e.g. Minerals, land ii) Multinational Resources: They are shared by more than one country e.g. Some rivers, lakes migratory animals. iii) International Resources: They are shared by all inhabitants of the earth. E.g. Sunlight air
- 7. DEPLETION AND DEGRADATION OF NATURAL RESOURCES There are four basic reasons for the depletion of natural resources: 1. Rapid Population increase: An increase in population will decrease all types of natural resources and result in environmental pollution. At present the world population is increasing by two percent every year There has been a tremendous increase in India’s Population and it has now crossed 1.35 billion The world cannot meet the continuously increasing demand for natural resources.
- 8. 2. Population : We are deteriorating our environment due to increase in population and industrial revolution.’ We are polluting the atmosphere, lakes streams, rivers by sewage, industrial wastes, heat, radioactive materials , detergents, fertilizers and pesticides. The uncontrolled and indiscriminate use of pesticides has disturbed the entire food chains by which animals including man are affected It has been estimated that average individual has about 7 parts per million(ppm) DDT in his body which affects in long term. Many gases e.g. Carbon monoxide Sulphur dioxide, nitrous oxide are known to cause respiratory troubles. The unplanned and uncontrolled industrial growth may adversely affect or destroy the health of the society
- 9. 3. Consumption of materials : Due to tremendous increase in population , most of the natural resources are being rapidly consumed. The high rate of consumption has disturbed our ecosystems. Many industries require raw materials which are essential for the advancement of the country. The rapid consumption will affect adversely the quality of our environment either by unwise use of natural resources or by increasing pollution.
- 10. 4. Deterioration of land: Due to excessive consumption of minerals of the soil by cropping or soil erosion or other natural events, fertility of soil is lost and the land deteriorates gradually Sometimes drought are also results in deterioration of land. Soil erosion has depleted soil fertility. Man has also deteriorated agriculture land and ultimately cause the loss of national economy.
- 11. FOREST RESOURCES The term forest is derived from a Latin word ’Foris’ which means out of doors or in other words the land beyond those areas of agriculture or Parks. Forest are plant formations composed of the crowns of trees forming a continuous canopy. Forest has been depleted at an alarming rate. According to the Indian State of Forest Report(ISFR) 2015, the total forest and tree cover is 79.42 million hectare, which is 24.16 percent of the total geographical area. Mizoram has the highest forest cover which is 99.93% .Large areas of forest are destroyed every year due to shifting cultivation.
- 12. USES OF FOREST RESOURCES Ecological Uses Forest are the natural habitat for wildlife. They can absorb toxic pollutants, gases and are good absorbers of noise. They help in regulating the earth’s climate and reduce global warming. They prevent soil erosion by binding the soil to the plant roots firmly and increase soil fertility. Commercial Uses Forest give us products like crayons, soap, suntan lotion, cork, dyes, writing paper, syrups, perfumes building materials. Honey, silk herbal medicines etc. IT also provides us different types of food products. They provide active ingredients for 25% of worl’s medicine and drugs. Firewood from forests is a source of enery. Wood is also used for furniture, industry, housing, and construction of road, railways.
- 13. OVEREXLOITATION OF FORESTS DEFORESTATION Deforestation is the clearing of virgin forests , or intentional destruction or removal of trees and other vegetation for agricultural, commercial, housing or firewood use without replanting(reforesting) and without allowing time for the forest to regenerate itself. Conversion of forests and woodlands for agricultural land to feed growing numbers of people Slash and burn Practice Felling of trees for firewood and building materials Illegal mining and quarrying in the forest area Construction of dams, hydroelectric projects, road constructions.
- 14. ENVIROMENTAL PROBLEMS CAUSED BY DEFORESTATION Atmospheric Change Deforestation is a contributor to global warming, by enhancing greenhouse effect. The water Cycle Trees extract groundwater through their roots and release it into the atmosphere. When part of a forest is removed, the trees no longer evaporate away this water, resulting in a much drier climate. Ecological Change Deforestation results in declines in biodiversity. It has been estimated that we are losing 137 plant, animal and insect species every single day due to deforestation. Soil Erosion With the loss of a protective cover of vegetation more soil is lost
- 15. CONTROLLING DEFORESTATION Reforestation and afforestation Planting of trees or seeds in order to transform open land into forest or woodland is termed as afforestation . Reforestation involves using native trees to restock already existing depleted forests. Awareness Raising awareness about the potential hazards that will accrue if deforestation and making placards saying “ plant more trees’ etc. Recycle Paper is one of the main factor for deforestation. Several paper products can be recycled. Plant trees Anyone can enlist the help of those around you and plant trees in the public places, like parks, gardens, play areas, etc.
- 16. WATER RESOURCES 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.97% of water on the Earth is salt water, leaving only 3% as fresh water of which slightly over two thirds is frozen in glaciers and polar ice caps. The remaining unfrozen fresh water is mainly found as ground water. Around 20 major cities in India face chronic or interrupted water shortages.
- 17. Use and over utilization of Surface Water Surface water is water collecting on the ground or in stream , river, lake, wetland or ocean. Surface water is used in domestic, agricultural, industrial, recreational purpose etc. The biggest advantage of using a surface-water supply as a surface water source is that these sources are readily located. The most significant disadvantage of using surface water as a water source is pollution. They are easily contaminated with water borne diseases and chemicals that enters the river or stream
- 18. SURFACE WATER STRESS Over utilization of surface water have brought stress in various ways Population growth: In 2000, the world population was 6.2 billion. The UN estimates that by 2050 there will be additional 3.5 billion people that suffer water stress. Increased affluence: The rate of poverty alleviation is increasing especially within the two population giants of China and India. However, increasing affluence inevitably means more water consumption: from needing clean fresh water 24 hours a day, 7 days a week and basic sanitation services Rapid Urbanization: Urbanization requires significant investment in water infrastructure. Climate change: Climate change could have significant impacts on water resources around the world because of the close connections between the climate and hydrologic cycle.
- 19. GROUNDWATER Ground water is water located beneath the ground surface in soil pore spaces and in the fractures of lithological formations. The ground water is not only an important component of water resources but also the major water supply source in many countries. Groundwater is often withdrawn for agricultural, municipal and industrial use by constructing and operating extraction wells. Exploitation and Utilization of Groundwater It was good quality because it is filtrated and cleaned . The investment of groundwater supply engineering is very little but the efficiency is fast Groundwater is polluted in many cities. Contaminated and polluted groundwater may harm agriculture , livestock and will also pose health risks to humans.
- 20. GROUNDWATER A. Overdraft: The most evident problem is a lowering of the water table beyond the reach of existing wells. B. The water table has dropped hundred of feet because of excessive well pumping. C. Subsidence: When groundwater is removed from aquifers by excessive pumping, pore pressures in the aquifer drop and may cause land subsidence, a drop in the ground surface. D. Seawater intrusion : Sea water moving inland is called a saltwater intrusion. This may happen due to overdraft. E. Mining: When the usage of water is greater than the recharge. It is referred to as mining water.
- 21. HOMEWORK CONFLICT OVER WATER Kaveri/Cauvery Water dispute The Indus water Treaty
- 22. MINERAL RESOURCES Minerals are formed over a period of millions of years. A mineral is a naturally occurring substance of definite chemical composition and identifiable physical properties. An ore is a mineral or combination of minerals form which a useful substance, such as metal m can be extracted. Mineral resource are those economic mineral concentrations which have undergone enough scrutiny to quantify their contained metal to a certain degree. Examples are iron, zinc, aluminum, manganese and copper
- 23. Environmental effects of extracting and using mineral resources Erosion: It results in the soil surface being removed and erosion Formation of sinkholes and land subsidence : Deep mining results in the subsidence of land and buckling of roads. Acid Mine drainage: Acidic mine water and chemicals from mines contaminate the ground water system and nearby surface water Loss of biodiversity: Mining results in the removal of topsoil and vegetal cover in order to extract the minerals. It leads to decline in the flora, fauna and land degradation. Air Pollution: Methane gas is a common source of ignition of explosions in coal mines and can result in violent coal dust explosions. Hearing Loss: Miners utilize equipment strong enough to break through extremely hard layers of the earth crust which can severely impact the hearing of the workers
- 24. FOOD RESOURCES Food is any substance , usually composed of carbohydrates, fats, proteins, and water that can be eaten or drank by an animal, including humans, for nutrition or pleasure. Today our food comes almost entirely form agriculture, animal husbandry and fishing. Around 15 plants and 8 species supply 90% of our food Wheat rice and corn provide approximately 50% of the calories human being consume and are a source of staple food for two third of the people. The healthiest diet recommended by food experts is a vegetarian diet. Malnutrition is a disorder dur to lack of proper food.