The storage sites for radioactive waste have become very controversial in almost every part of the world because of the threats they pose to the surrounding environment. Future of Nuclear Energy As of November 2020, India has 22 nuclear reactors in operation in 7 nuclear power plants, with a total installed capacity of 6,780 MW. Nuclear power produced a total of 35 TW and supplied 3.22% of Indian electricity in 2017. Seven more reactors are under construction with a combined generation capacity of 4,300 MW. Nations such as Lithuania, France, and Slovakia create almost all of their electricity from nuclear power plants. Nuclear power plants do not have the capability to safely and reliably produce energy from nuclear fusion. It's not clear whether the process will ever be an option for producing electricity. Nuclear engineers are researching nuclear fusion, however, because the process will likely be safe and cost-effective. 2.7.3 Solar Energy The sun is our most powerful source of energy. Sunlight, or solar energy, can be used for heating, lighting and cooling homes and other buildings, generating electricity, water heating, and a variety of industrial processes. Most forms of renewable energy come either directly or indirectly from the sun. For example, heat from the sun causes the wind to blow, contributes to the growth of trees and other plants that are used for biomass energy, and plays an essential role in the cycle of evaporation and precipitation that makes hydropower possible. Solar energy can be used directly or indirectly for human welfare. Direct solar energy is the radiant energy, whereas indirect solar energy is energy obtained from materials that have previously incorporated the sun’s radiant energy. Solar energy can be used for direct heating, and alternatively the heat converted into electricity (thermal electric generation). Photovoltaic devices (PV Devices) or solar cells convert direct solar energy into electricity. PV systems are often used in remote locations that are not connected to the electric grid. They are also used to power watches, calculators, and lighted road signs. Solar Power Plants indirectly generate electricity when the heat from solar thermal collectors is used to heat a fluid which produces steam that is used to power generator. A backup system is required to store and generate electricity when solar power is not operative at night or during cloudy days. 51 CU IDOL SELF LEARNING MATERIAL (SLM)
Solar Energy in India Including both ground and roof mounted plants, the country's installed solar power capacity was 36,910 MW as of 30 November 2020. Solar electricity generation from April 2019 to March 2020 was 50.1 TWh, or 3.6% of total generation (1,391 TWh). 2.7.4 Hydrogen Energy as An Alternative Future Source of Energy Hydrogen is the simplest and most abundant element on earth—it consists of only one proton and one electron. Hydrogen can store and deliver usable energy, but it doesn't typically exist by itself in nature and must be produced from compounds that contain it. Sources of Hydrogen Hydrogen can be produced from diverse, domestic resources. Currently, most hydrogen is produced from fossil fuels, specifically natural gas. Electricity from the grid or from renewable sources such as biomass, geothermal, solar, or wind is also currently used to produce hydrogen. In the longer term, solar energy and biomass can be used more directly to generate hydrogen as new technologies make alternative production methods cost competitive. Production Pathways Most hydrogen can also be produced through steam methane reforming, a high temperature process in which steam reacts with a hydrocarbon fuel to produce hydrogen. Another common hydrogen production method takes water, and separates the molecule H2O into oxygen and hydrogen through a process called electrolysis. Electrolysis takes place in an electrolyze, which functions much like a fuel cell in reverse i.e., instead of using the energy of a hydrogen molecule, like a fuel cell does, an electrolyze produces hydrogen from water molecules. Biological processes can also produce hydrogen through biological reactions using microbes such as bacteria and microalgae. In these processes, microbes consume plant material and produce hydrogen gas. There are many ways to produce hydrogen using sunlight, including photobiological, photoelectrochemical, photovoltaic-driven electrolysis, and solar thermochemical processes. Hydrogen as an Energy Carrier 52 CU IDOL SELF LEARNING MATERIAL (SLM)
Hydrogen is an energy carrier, not an energy source and can deliver or store a tremendous amount of energy. Hydrogen can be used in fuel cells to generate electricity, or power and heat. Today, hydrogen is most commonly used in petroleum refining and fertilizer production, while transportation and utilities are emerging markets. Uses for Hydrogen Hydrogen is a clean fuel that, when consumed in a fuel cell, produces only water, electricity, and heat. Hydrogen and fuel cells can play an important role in our national energy strategy, with the potential for use in a broad range of applications, across virtually all sectors viz. transportation, commercial, industrial, residential, and portable technologies. Hydrogen and fuel cells can provide energy for use in diverse applications, including distributed or combined-heat-and-power; backup power; systems for storing and enabling renewable energy; portable power; auxiliary power for trucks, aircraft, rail, and ships; specialty vehicles such as forklifts; and passenger and freight vehicles including cars, trucks, and buses. Due to their high efficiency and zero-or near zero-emissions operation, hydrogen and fuel cells have the potential to reduce greenhouse gas emission in many applications. 2.7.5 Biomass and Biogas Among various energy resources where solar energy is utilized indirectly, biomass energy is the most important one. Biomass energy is obtained from those materials whose origin can be traced to photosynthesis such as live plant material and dried residues, fresh water and marine algae, agricultural and forest residues (e.g., straw, husks, corn cobs, bark, sawdust, roots, animal wastes) etc. Biomass also includes biodegradable organic wastes from industries like sugar mills, breweries, etc. At least half of the world’s population relies upon biomass as their main source of energy. In India, fuel wood is still a major source of energy for domestic purposes in rural areas. Biomass fuel, which can be a solid, liquid or gas, is burned to release its energy. Solid biomass includes wood, charcoal, animal dung and peat. Municipal Solid Wastes (MSW) can be a source of energy by either burning MSW in waste-to-energy plants, or by capturing biogas. In waste-to-energy plants, trash is burned to produce steam that can be used either to heat buildings or to generate electricity. Biomass can be converted to liquid fuels especially methanol and ethanol which can be used in internal combustion. 53 CU IDOL SELF LEARNING MATERIAL (SLM)
Ethanol is an alcohol fuel made from the sugars found in grains, such as corn, sorghum, and wheat, as well as potato skins, rice, sugar cane, sugar beets, and yard clippings. Biodiesel is a fuel made with vegetable oils, fats, or greases such as recycled restaurant grease. Biodiesel fuels can be used in diesel engines without changing them. Biodiesel, a renewable fuel, is safe, biodegradable, and reduces the emissions of most air pollutants. Biomass, particularly animal waste, can also be converted into biogas in biogas digesters by using the process of microbial decomposition. Biogas is a clean fuel whose combustion produces fewer pollutants than other combustible energy resources. It is composed of a mixture of gases and can be stored and transported easily. Production of biomass for energy requires sufficient area of land and water. Energy plantations of plant species, showing high calorific value and growth rate, are raised in selected areas to produce biomass. Biogas in India Biogas in India has been traditionally based on dairy manure as feed stock and these \"Gobar\" gas plants have been in operation for a long period of time, especially in rural India. In the last 2–3 decades, research organizations with a focus on rural energy security have enhanced the design of the systems resulting in newer efficient low-cost designs such as the Deenabandhu model. The Deenabandhu Model is a new biogas-production model popular in India. (Deenabandhu means \"friend of the helpless.\") The unit usually has a capacity of 2 to 3 cubic metres. It is constructed using bricks or by a ferrocement mixture. In India, the brick model costs slightly more than the ferrocement model; however, India's Ministry of New and Renewable Energy offers some subsidy per model constructed. Biogas which is mainly methane/natural gas can also be used for generating protein rich cattle, poultry and fish feed in villages economically by cultivating Methyl coccus capsulatus bacteria culture with tiny land and water foot print. The carbon dioxide gas produced as by product from these plants can be put to use in cheaper production of algae oil or spirulina from algaculture particularly in tropical countries like India which can displace the prime position of crude oil in near future. Union government of India is implementing many schemes to utilize productively the agro waste or biomass in rural areas to uplift rural economy and job potential. 54 CU IDOL SELF LEARNING MATERIAL (SLM)
With these plants, the non-edible biomass or waste of edible biomass is converted in to high value products without any water pollution or greenhouse gas (GHG) emissions. In India, Nepal, Pakistan and Bangladesh biogas produced from the anaerobic digestion of manure in small-scale digestion facilities of gobar gas. It is estimated that such facilities exist in over 2 million households in India, 50,000 in Bangladesh and thousands in Pakistan, particularly North Punjab, due to the thriving population of livestock. 2.8 SUMMARY Resources can be categorized as inexhaustible and exhaustible. Most of the biotic resources are renewable. Renewable resources are continuously regenerated. Many abiotic resources are non-renewable e.g., fossil fuels (coal, petroleum and gas) as they cannot be regained or reconstructed once they are used up. Approximately one-third of the earth’s total land area is covered by forests. The main causes of deforestation are expansion of agriculture, urbanization, industrialization, excessive commercial use of timber, fuel wood, and other forest products and over grazing. Deforestation results in increased soil erosion, extinction of bio diversity and contributes to global warming. About three-fourth of the earth’s surface is occupied by oceans which contain about 97.5 % of the earth’s water in strongly saline condition. The rest 2.5% is fresh water. A mineral is a naturally occurring substance formed through geological processes that has a characteristic chemical composition, a highly ordered atomic structure and specific physical properties. Mining not only disturbs and damages the land, but also pollutes the soil, water and air. Recycling and reusing of minerals resources helps in reducing the amount of solid waste, energy consumption and pollution. Hydro energy is simply energy that is taken from water and converted to electricity. Hydro energy can be obtained by using many methods of capture. Energy from ocean waves and tides can be harnessed to generate electricity, and ocean thermal energy from the heat stored in sea water can also be converted to electricity. Nuclear reactors use fission, or the splitting of atoms, to produce energy. Nuclear energy can also be produced through fusion, or joining (fusing) atoms together. Radioactive waste is long-lasting. Materials like clothes and tools can stay radioactive for thousands of years. 55 CU IDOL SELF LEARNING MATERIAL (SLM)
Direct solar energy is the radiant energy, whereas indirect solar energy is energy obtained from materials that have previously incorporated the sun’s radiant energy. Photovoltaic devices (PV Devices) or solar cells convert direct solar energy into electricity. Solar Power Plants indirectly generate electricity when the heat from solar thermal collectors is used to heat a fluid which produces steam that is used to power generator. Hydrogen can store and deliver usable energy, but it doesn't typically exist by itself in nature and must be produced from compounds that contain it. Hydrogen can be produced from diverse, domestic resources. Currently, most hydrogen is produced from fossil fuels, specifically natural gas. Due to their high efficiency and zero-or near zero-emissions operation, hydrogen and fuel cells have the potential to reduce greenhouse gas emission in many applications. Biomass energy is obtained from those materials whose origin can be traced to photosynthesis such as live plant material and dried residues, fresh water and marine algae, agricultural and forest residues (e.g., straw, husks, corn cobs, bark, sawdust, roots, animal wastes) etc. Biodiesel is a fuel made with vegetable oils, fats, or greases such as recycled restaurant grease. Biodiesel fuels can be used in diesel engines without changing them. Biomass, particularly animal waste, can also be converted into biogas in biogas digesters by using the process of microbial decomposition. 2.9 KEYWORDS Biodiesel is a fuel made with vegetable oils, fats, or greases such as recycled restaurant grease. Biodiesel fuels can be used in diesel engines without changing them. The process of removal of superficial layer of the soil from one place to another is called Soil Erosion. The process of deterioration of soil or loss of fertility is known as Land Degradation or Soil Degradation. Desertification is a progressive destruction or degradation of arid or semi-arid lands. Hydro Energy is simply energy that is taken from water and converted to electricity. Photovoltaic Devices (PV Devices) or solar cells convert direct solar energy into electricity. Radioactivity is defined as the emission of ionizing radiation or particles caused by the spontaneous disintegration of atomic nuclei. A Nuclear Reactor, or power plant, is a series of machines that can control nuclear fission to produce electricity 56 CU IDOL SELF LEARNING MATERIAL (SLM)
A Greenhouse Gas is a gas that absorbs and emits radiant energy within the thermal infrared range, causing the greenhouse effect. The primary greenhouse gases in Earth's atmosphere are water vapor, carbon dioxide, methane, nitrous oxide, and ozone. 2.10 LEARNING ACTIVITY 1. Discuss what is happening with our world energy supply from fossil fuels and other non- renewable resources. (Examples: fossil fuels are being dangerously depleted, the rich countries receive a larger share of the energy and are more wasteful with it, wars are developing, the scientists and engineers are researching and developing renewable energy sources, etc.) ___________________________________________________________________________ ___________________________________________________________________________ 2.11 UNIT END QUESTIONS A. Descriptive Questions Short Questions 1. Differentiate between renewable and non-renewable resources with suitable examples. 2. State the role of individual in conserving natural resources. 3. List out the causes and effects of deforestation. 4. Why is there a pressing need of alternate energy sources? 5. Enumerate the environmental impacts of nuclear reactor. Long Questions 1. Discuss in detail the causes, effects and conservative measures of soil erosion. 2. Write short notes on the conservation and management of water resources. 3. Classify minerals and give a brief note on conservation of minerals. 4. Hydrogen energy as an alternative future source of energy – Discuss. 5. Summarize the various sources and uses of biomass and biogas. B. Multiple Choice Questions 1. Choose the non-renewable resource from below a. Water b. Forests c. Minerals d. Land 57 CU IDOL SELF LEARNING MATERIAL (SLM)
2. Gravitational pull exerted by the sun and moon causes _______ to develop a. Waves b. Tides c. Wind d. Solar flares 3. The minimum arable land required to sustainably support one person is a. 0.07 ha b. 0.70 ha c. 7.0 ha d. 70 ha 4. _______ is a fuel made with vegetable oils, fats, or greases such as recycled restaurant grease. a. Biogas b. Biomass c. Biodiesel d. Hydrogen 5. Sunlight can be converted into electricity directly by a. Photovoltaic cells b. Solar power plants c. Solar heaters d. Hydrogen fuel cell Answer 1-c, 2-b, 3-a, 4-c, 5-a 2.12 REFERENCES Reference Books Erach Bharucha, “Textbook of Environmental Studies” University Press India Pvt. Ltd., Hyderabad, 2015. G. Tyler Miller, Jr. and Scott E. Spoolman “Environmental Science” Thirteenth Edition, Cengage Learning, 2010. Gilbert M. Masters and Wendell P. Ela “Introduction to Environmental Engineering and Science‟, 3rd edition, Pearson Education, 2013 58 CU IDOL SELF LEARNING MATERIAL (SLM)
Websites www.fao.org www.energy.gov.org 59 CU IDOL SELF LEARNING MATERIAL (SLM)
UNIT 3– ENVIRONMENTAL POLLUTION AND THEIR EFFECTS Structure 3.0 Learning Objectives 3.1 Introduction 3.2 Water Pollution 3.3 Land Pollution 3.4 Noise Pollution 3.5 Air Pollution 3.6 Current Environmental Issues of Importance 3.6.1 Population growth 3.6.2 Climate Change and Global Warming 3.6.3 Automobile Pollution 3.6.4 Acid Rain 3.6.5 Ozone Layer Depletion 3.7 Environmental Protection Act 3.8 Water Prevention & Control Act 3.9 Air Prevention & Control of Pollution Act 3.10 Salient Features of Environmental Summit – Paris 2015 3.11 Summary 3.12 Learning Activity 3.13Unit end Questions 3.14 References 3.0 LEARNING OBJECTIVES After studying this unit students will be able to Acquire basic understanding of sources, effects and control of environmental pollution Explain the salient features of Environmental Protection Act, Water Prevention and Control Act, Air Prevention and Control of Pollution Act. 60 CU IDOL SELF LEARNING MATERIAL (SLM)
3.1 INTRODUCTION Environmental pollution is not a new phenomenon, yet it remains the world’s greatest problem facing humanity, and the leading environmental causes of morbidity and mortality. Man’s activities through urbanization, industrialization, mining, and exploration are at the forefront of global environmental pollution. Both developed and developing nations share this burden together, though awareness and stricter laws in developed countries have contributed to a larger extent in protecting their environment. Despite the global attention towards pollution, the impact is still being felt due to its severe long-term consequences. 3.2 WATER POLLUTION Water Pollution is defined as alteration in the physical, chemical or biological characteristics of water, making it unsuitable for intended use in its natural state Water Pollution is the contamination of water by foreign matter such as micro- organisms, chemicals, industrial or other wastes, or sewage. Such matter deteriorates the quality of the water and renders it unfit for its intended uses. Sources of Water Pollution • Point sources (Direct sources) are specific sites near water bodies which directly discharge effluents into them. E.g., industries, power plants, offshore oil wells, etc. • Nonpoint source (Indirect sources) are big land areas that discharge pollutants indirectly through environmental changes. E.g., contaminants that enter the water supply from soils/groundwater systems and from the atmosphere via rain water. Industrial effluents Domestic sewage Fertilizers and pesticides from agricultural lands Leachate from solid waste disposal sites Types of Water Pollutants • Disease causing agents: Bacteria, viruses, protozoa, parasitic worms • Oxygen demanding wastes: Organic waste which are decomposed by oxygen consuming bacteria • Water soluble inorganic chemicals: Acids, salts, compounds of toxic metals such as lead and mercury • Inorganic plant nutrients: Water soluble nitrate and phosphate compounds 61 CU IDOL SELF LEARNING MATERIAL (SLM)
• Organic chemicals: Oil, gasoline, plastics, pesticides, cleaning solvents, detergents • Sediment or suspended matter: Insoluble particles of soil and other solid inorganic and organic materials that become suspended in water • Radioactive substances: Radioisotopes that are water soluble or capable of being biologically amplified to higher concentrations as they pass through food chains or food webs • Water soluble inorganic chemicals: Acids, salts, compounds of toxic metals such as lead and mercury • Heat: Large quantity of water is heated when it is used in the cooling towers of thermal power plants Effects of Water Pollution Water borne infectious diseases • Waterborne diseases occur when parasites or other disease-causing microorganisms are transmitted via contaminated water, particularly water contaminated by pathogens. • These include typhoid, intestinal parasites, and most of the enteric and diarrheal diseases caused by bacteria, parasites, and viruses. • Polluted beach water can cause rashes, ear aches, pink eye, respiratory infections, hepatitis, encephalitis, gastroenteritis, diarrhea, vomiting, and stomach aches. • Water-borne diseases are infectious diseases spread primarily through contaminated water. Though these diseases are spread either directly or through flies or filth, water is the chief medium for spread of these diseases and hence they are termed as water- borne diseases. Cause Water-borne diseases Bacterial infections Typhoid Cholera Viral infections Paratyphoid fever Protozoal infections Bacillary dysentery Infectious Hepatitis (jaundice) Poliomyelitis Amoebic dysentery Nutrient pollution • Water pollution in coastal zones stimulates the growth of certain toxic algae. • Zooplankton eat the toxic algae and begin passing the toxins up the food chain, affecting edibles like clams, and ultimately working their way up to seabirds, marine mammals, and humans. • The result can be illness and sometimes death. Eutrophication 62 CU IDOL SELF LEARNING MATERIAL (SLM)
• Eutrophication is a process whereby water bodies, such as lakes, estuaries, or slow- moving streams receive excess nutrients (mainly nitrogen and phosphorus) that stimulate excessive plant growth (algae, periphyton attached algae, and nuisance plants weeds). • This enhanced plant growth, often called an algal bloom, reduces dissolved oxygen in the water when dead plant material decomposes and can cause other organisms to die. Chemical contamination Chemical water pollution typically occurs because • The chemicals are dumped into the water intentionally. • The chemicals seep into groundwater, streams, or rivers because of failing pipes or storage tanks. • The chemicals catastrophically contaminate waterways because of industrial accidents. • The pollution settles out of polluted air (or was precipitated out of polluted air). • Chemicals leache out of contaminated soil. • Severe chemical spills and leaks into surfaces waters usually have an immediate effect on aquatic life (fish etc.). • Pesticides can migrate via water into the food chain as well, ultimately being consumed by humans or animals in food. CHEMICALS EFFECTS Pesticides Damage nervous system, Cause cancer Lead Affects Central nervous system Fluoride Fluorosis (Yellowing of teeth), damage to spinal cord and other crippling diseases Nitrates Blue baby syndrome (methemoglobinemia), causes algal bloom Petrochemicals Cause cancer Chlorinated solvents Reproduction disorders Control Measures • Pollution control of urban settlement • Sewerage regulation • Proper pattern of sewerage collection system • Pollution control of industrial sources • Recycle and reuse of treated wastewater • Judicious use of pesticides and fertilizers • Afforestation • Enforcement of rules and regulations 63 CU IDOL SELF LEARNING MATERIAL (SLM)
Solutions to water pollution caused by excess nutrients and chemical pesticides are as follows: • Encourage smart agricultural practices... • Reduce urban/suburban runoff of lawn fertilizers and pesticides... • Prevent further destruction wetlands… • Improve sewage treatment… Do not use excess fertilizers • Use fertilizers in minimum quantities and avoid applying fertilizers when it is raining. 3.3 LAND POLLUTION Land pollution is the degradation of the Earth's land surface through misuse of the soil by poor agricultural practices, mineral exploitation, industrial waste dumping, and indiscriminate disposal of urban wastes. Soil pollution is defined as the change in physical, chemical and biological conditions of the soil through man’s intervention resulting in the degradation in quality and productivity of the soil Contamination of soil with sewage sludge, industrial sludge, solid wastes, dump site leachates, agrochemicals and radioactive substances is called soil pollution. Causes of Land Pollution Deforestation Agricultural activities Unskilled irrigation Overcrowded landfills Mining activities Shifting cultivation Acid rain Sources of Land Pollution Industrial effluents Metallic pollutant Biological agents Radioactive pollutants Pesticides, Herbicides, Fungicides, Insecticides Fertilizers Polymers, Plastics and other wastes Effects of Land Pollution 64 CU IDOL SELF LEARNING MATERIAL (SLM)
Soil erosion Change in climate pattern Contamination of underground ad surface water Environmental impacts Effect on human health Cause air pollution Distraction for tourists Effect on wildlife Global warming Biomagnification Land pollution can affect wildlife, plants, and humans in a number of ways, such as: Cause problems in the respiratory system Cause problems on the skin Lead to birth defects Cause various kinds of cancers The toxic materials that pollute the soil can get into the human body directly by: Coming into contact with the skin Being washed into water sources like reservoirs and rivers Eating fruits and vegetables that have been grown in polluted soil Breathing in polluted dust or particles Organic wastes enter the soil pores and decompose. Pathogenic bacteria spread infection Compounds containing arsenic, mercury, chromium, nickel, etc. are toxic to life Excess use of Na, Mg, Ca, K, S, etc. in the form of fertilizers and pesticides inhibit plant growth and reduce crop yield Water logging and salinity increases the dissolved salt content in ground water and also the soil Prevention of Land Pollution People should be educated and made aware about the harmful effects of littering Effluents should be properly collected and disposed of by appropriate method From the wastes recovery of useful products should be made Inorganic matter such as paper, plastic, glass and metals should be reclaimed and then recycled Personal litter should be disposed properly 65 CU IDOL SELF LEARNING MATERIAL (SLM)
Organic waste matter should be disposed in areas that are far away from residential places Treat the sewage before land disposal Rotate the crop pattern to allow the soil replenish the nutrients Preserve and protect top fertile soil. Control soil erosion by proper tree plantation measures Fertilizers may be applied only after estimating soil and crop measures Microbial degradation of biodegradable substances is also one of the scientific approaches for reducing soil pollution 3.4 NOISE POLLUTION The sensation which is pleasing to the ears, which is melodious and which gives comfort like musical notes is defined as sound While the one which is penetrating and uncomfortable, which creates psychological stress is called as noise Noise pollution is displeasing human or machine created sound that disrupts the activity or happiness of human or animal life. Sounds produced at high decibels which causes discomfort to human ears is called noise. Noise may be defined as an unwanted sound at the wrong time and a wrong place. NOISE SOURCES Road Traffic Noise The main sources of traffic noise are the motors and exhaust system of autos, smaller trucks, buses, and motorcycles. This type of noise can be augmented by narrow streets and tall buildings, which produce a canyon in which traffic noise reverberates. Air Craft Noise Noise from railroads The noise from locomotive engines, horns and whistles, and switching and shunting operation in rail yards can impact neighboring communities and railroad workers. Construction Noise The noise from the construction of highways, city streets, and buildings is a major contributor to the urban scene. Construction noise sources include pneumatic hammers, air compressors, bulldozers, loaders, dump trucks (and their back-up signals), and pavement breakers. Noise in Industry The most offending noise sources are: • Compressors 66 CU IDOL SELF LEARNING MATERIAL (SLM)
• Generators • Furnaces • Looms • Grinding mills • Releasing valves • Noise from Consumer products Certain household equipment, such as vacuum cleaners and some kitchen appliances have been and continue to be noisemakers, although their contribution to the daily noise dose is usually not very large. Noise in building – Apartment dwellers are often annoyed by noise in their homes, especially when the building is not well designed and constructed. – In this case, internal building noise from plumbing, boilers, generators, air conditioners, and fans, can be audible and annoying. – Improperly insulated walls and ceilings can reveal the sound of-amplified music, voices, footfalls and noisy activities from neighboring units. Domestic Noise Pollution • Transistors • Radio • TV • Musical Instruments • Air Conditioners • Washing Machines IMPACTS OF NOISE Often neglected, noise induces a severe impact on humans and on living organisms. Some of the adverse effects are summarized below: Annoyance: It creates annoyance to the receptors due to sound level fluctuations. The aperiodic sound due to its irregular occurrences causes displeasure to hearing and causes annoyance. Physiological effects: The physiological features like breathing amplitude, blood pressure, heart-beat rate, pulse rate, blood cholesterol isaffected. Loss of hearing: Long exposure to high sound levels cause loss of hearing. This is mostly unnoticed, but has an adverse impact on hearing function. Human performance: The working performance of workers/human will be affected as they'll be losing their concentration. Nervous system: It causes pain, ringing in the ears, feeling of tiredness, thereby effecting the functioning of human system. 67 CU IDOL SELF LEARNING MATERIAL (SLM)
Sleeplessness: It affects the sleeping there by inducing the people to become restless and lose concentration and presence of mind during their activities. Damage to material:The buildings and materials may get damaged by exposure to infrasonic / ultrasonic waves and even get collapsed. Noise Management Strategy Fig 3.1 Noise Survey NOISE CONTROL Noise control at source The noise pollution can be controlled at the source of generation itself by employing techniques like- Reducing the noise levels from domestic sectors: The domestic noise coming from radio, tape recorders, television sets, mixers, washing machines, 68 CU IDOL SELF LEARNING MATERIAL (SLM)
cooking operations can be minimized by their selective and judicious operation. Maintenance of automobiles: Regular servicing and tuning of vehicles will reduce the noise levels. Fixing of silencers to automobiles, two wheelers etc., will reduce the noise levels. Noise barriers in roadways Vehicle speed limitation Alteration of roadway surface texture Limit heavy duty vehicles Traffic controls and tire designs Control over vibrations: The vibrations of materials may be controlled using proper foundations, rubber padding etc. to reduce the noise levels caused by vibrations. Low voice speaking: Speaking at low voices enough for communication reduces the excess noise levels. Prohibition on usage of loud speakers: By not permitting the usage of loudspeakers in the habitant zones except for important meetings / functions. Selection of machinery: Optimum selection of machinery tools or equipment reduces excess noise levels. Maintenance of machines: Proper lubrication and maintenance of machines, vehicles etc. will reduce noise levels. Control in the transmission path Installation of barriers: Installation of barriers between noise source and receiver can attenuate the noise levels. Design of building: The design of the building incorporating the use of suitable noise absorbing material for all/door/window/ceiling will reduce the noise levels. Installation of panels or enclosures: A sound source may be enclosed within a paneled structure such as room as a means of reducing the noise levels at the receiver. Green belt development: Green belt development can attenuate the sound levels. Use of protective equipment The usage of protective equipment and the worker's exposure to the high noise levels can be minimized by: Job rotation: By rotating the job between the workers working at a particular noise source or isolating a person, the adverse impacts can be reduced. 69 CU IDOL SELF LEARNING MATERIAL (SLM)
Exposure reduction: Regulations prescribe that, noise level of 90 dB for more than 8 hr. continuous exposure is prohibited. Hearing protection: Equipment like earmuffs, ear plugs etc. are the commonly used devices for hearing protection. 3.5 AIR POLLUTION Air pollution is defined as the excessive concentration of foreign matter in the air which adversely affects the wellbeing of the individual or causes damage to the property. SOURCES OF AIR POLLUTION Natural Volcanic eruptions, forest fires, pollen grains, biological decay, etc. Manmade or Anthropogenic Thermal power plants, vehicular emissions, fossil fuel burning, agricultural activities, etc. Manmade or Anthropogenic Sources Point Sources (large stationary sources) Area Sources (small stationary sources and mobile sources with indefinite routes) Line sources (mobile sources with definite routes) TYPES OF POLLUTANTS Primary Air Pollutants - Emitted directly from identifiable sources. E.g., CO, SO2 Secondary Air Pollutants - Produced by the interaction among two or more primary pollutants. E.g., SO3, H2SO4, HNO3 EFFECTS ON HUMANS Influencing factors Nature of the pollutants Concentration of the pollutants Duration of the exposure State of health of receptor Age of the receptor Natural Contaminants 70 Includes the allergens such as pollen grains, spores, etc., CU IDOL SELF LEARNING MATERIAL (SLM)
Cause bronchitis, bronchial asthma and dermatitis Cause hay fever Suspended Particulate Matter Source: Industrial plants, power plants, agriculture, unpaved roads, etc. Suspended matter consists of dust, fumes, mists and smoke The main chemical component of SPM that is of major concern is lead, others being nickel, arsenic, and those present in diesel exhaust These particles when breathed in, lodge in our lung tissues and cause lung damage and respiratory problems Carbon Monoxide Source: Cigarette smoking, Incomplete burning of fossil fuels, Vehicle exhaust. Carbon monoxide has a strong affinity for combining with hemoglobin of the blood to form carboxyhemoglobin which reduces the ability of the hemoglobin to carry oxygen to body tissues Carbon monoxide affects the central nervous system Carbon monoxide is responsible for heart attacks and high mortality rate Sulphur Dioxide Source: Coal burning in power plants, Industrial processes SO2 is an irritant gas which affects the mucous membranes when inhaled Under certain conditions, some of the air-borne Sulphur dioxide gas is oxidized to Sulphur trioxide SO2 and SO3 in the presence of water vapor or water, forms sulphuric acid Sulphur trioxide is a very strong irritant, much stronger than Sulphur dioxide, causing severe bronchospasms at relatively low levels of concentration Oxides of Nitrogen Source: Fossil fuel burning, vehicle exhaust, power plants Nitric oxide and nitrogen dioxide affect human health Causes eye irritation and nasal irritation It also results in pulmonary discomfort Forms photochemical smog Ozone Source: Chemical reaction with volatile organic compounds and nitrogen oxides 71 CU IDOL SELF LEARNING MATERIAL (SLM)
Ozone is an irritant gas that affects the respiratory tract, reaching much deeper into the lungs The lining of our airways loses some of its ability to serve as a protective barrier to microbes, toxic chemicals, and allergens Ozone also triggers asthma and may aggravate other respiratory illnesses such as pneumonia and bronchitis Ozone may reduce the human immune system’s ability to fight bacterial infections in the respiratory system Radioactive Substances Source: Nuclear power plants, testing of nuclear bombs, agricultural, industrial and medical use of radioactive isotopes Causes anemia and leukemia Causes genetic effects and sterility Shortens the life span of individuals Insect ides Affect the central nervous system and other vital organs Causes premature labor and abortion Gets concentrated in the body of expectant mothers EFFECTS OF AIR POLLUTANTS ON PLANTS Necrosis – killing or collapse of tissue Chlorosis – loss or reduction of chlorophyll Abscission – dropping of leaves Epinasty – downward curvature of leaf Pollutant Dose Effect Sulphur Mild Interveinal chlorotic bleaching of leaves Dioxide Severe Necrosis in interveinal areas Flecks on upper leaves, premature aging and Ozone Mild suppressed growth Collapse of leaf, necrosis and bleaching Fluorides Severe NO2 Cumulative Necrosis at leaf tip Ethylene effect Mild Suppressed growth, leaf bleaching Mild Epinasty, Leaf abscission 72 CU IDOL SELF LEARNING MATERIAL (SLM)
PAN Mild Bronzing of lower leaf surface, suppressed growth EFFECTS OF AIR POLLUTANTS ON ANIMALS Bone lesions Malnutrition Lowered fertility Growth retardation Paralysis Mutation effect ECONOMIC EFFECTS OF AIR POLLUTANTS Corrosion of metals Soiling and eroding of building materials Fading of dyed materials Rubber cracking Deterioration of works of art Effects on humans, plants and animals Materials Pollutants Effects Corrosion, spoilage of surface, loss of metal, Metals SO2, acid gases tarnishing Discoloration, leaching Building SO2, acid gases materials Discoloration SO2, H2S Paint Particulates Deterioration, reduced tensile strength, fading SO2, acid gases, Cracking, Weakening Textiles and NO2, O3 Disintegration, Powdered surface textile dyes Oxidants, O3 Embrittlement Rubber SO2, acid gases Change in surface appearance Leather SO2, acid gases Paper Acid gases Ceramics CONTROL OF AIR POLLUTION Reduction of pollutant discharge at the source by the application of control equipment 73 CU IDOL SELF LEARNING MATERIAL (SLM)
Reduction at the source through raw material changes, operational changes or modification or replacement of process equipment Dilution of source discharge by the use of tall stacks Dispersion of source locations through allocation of land usage i.e., proper planning and zoning of industrial areas Control by Equipment Settling Chambers Inertial separators Baffle type Louvre type Dust traps Cyclones Tangential inlet Involute inlet Single and multiple cyclones Filters Fabric or cloth filters Fibrous or deep bed filters Electrostatic precipitators Single stage and Two stage Pipe type and Plate type Dry and Wet type Scrubbers or wet collectors Spray towers Venturi scrubbers Cyclone scrubbers Packed scrubbers Mechanical scrubbers Control by Process Changes Substitution of raw materials or fuels Modification of the process itself Modification or replacement of the process equipment Changes in operational practices Control Measures 74 Pollution control of industries Management of various wastes from a community CU IDOL SELF LEARNING MATERIAL (SLM)
Diffusion/dilution of pollutants Proper zoning of industries and city planning Development of green belts Reducing vehicular emissions Ban on open dumping of wastes Enactment of law 3.6 CURRENT ENVIRONMENTAL ISSUES OF IMPORTANCE 3.6.1 Population Growth Causes of Population Growth • Conquest of diseases • Improvement in public sanitation • High infant mortality • Poverty • Preference for sons • Early marriages • Illiteracy Problems of Population Growth Increasing demands for food and natural resources. Affects natural resource availability Deforestation Ecological imbalance Inadequate housing and health services Loss of agricultural lands Unemployment and socio-political unrest Environmental pollution Factors affecting variation of population • Age of human settlement • Accessibility of area • Cultural factors • Soils • Climatic conditions • Natural resources 75 CU IDOL SELF LEARNING MATERIAL (SLM)
3.6.2 Climate Change and Global Warming GREENHOUSE EFFECT • When sunlight reaches Earth's surface some is absorbed and warms the earth and most of the rest is radiated back to the atmosphere at a longer wavelength than the sun light. • Some of these longer wavelengths are absorbed by greenhouse gases in the atmosphere before they are lost to space. • The absorption of this long wave radiant energy warms the atmosphere. • These greenhouse gases act like a mirror and reflect back to the Earth some of the heat energy which would otherwise be lost to space. • The reflecting back of heat energy by the atmosphere is called the \"greenhouse effect\". • The chemical substances that increase the earth’s surface temperature are called greenhouse gases Fig 3.2 Greenhouse Effect Major Greenhouse Gases Average time Relative warming Green House Gas Human Source in potential 76 CU IDOL SELF LEARNING MATERIAL (SLM)
troposphere (compared to CO2) 1 Carbon Dioxide, Fossil Fuel burning, 50 -120 yrs. CO2 Deforestation and Plant 23 burning Methane, CH4 Rice paddies, 12-18yrs Guts of cattle and termites, Landfills, Coal Production, Natural gas leaks from oil and gas production Nitrous oxide, N2O Fossil fuel burning, 114-120 yrs. 296 Fertilizers, Livestock wastes, Nylon Production Chlorofluorocarbons Air Conditioners, 11-20 yrs. 900 - 8300 (CFCs) Refrigerators, Plastic (965-110yrs in Foams stratosphere) Hydrochloric Air Conditioners, 9-390 yrs. 470-2000 Refrigerators, Plastic Fluorocarbons, Foams HCFCs Hydrofluorocarbons Air Conditioners, 15-390 yrs. 130-12700 Refrigerators, Plastic Foams Halons Fire Extinguishers 65 yrs. 5500 Carbon Cleaning solvent 42 yrs. 1400 tetrachloride, CCl4 Effects of greenhouse gases Heat waves associated with land temperature increase and thousands of people will die through future heatwaves. Droughts will become more prolonged and be even more devastating than anything we have experienced. This is because higher temperatures evaporate water from the land, which will also give rise to more wildfires. 77 CU IDOL SELF LEARNING MATERIAL (SLM)
Agriculture and food crops will be devastated in some regions and diseases like malaria and dengue fever will increase as conditions favourable to these diseases spread. Higher ocean temperatures increase the power in cyclones and hurricanes, and we will see a higher frequency of severe storms and associated flooding that will do extraordinary damage to infrastructure, and destroy houses, towns and villages. Rising sea levels will displace millions of people, and the geography of the land will change dramatically, with millions needing to be relocated along with loss of buildings. GLOBAL WARMING • Global warming is the gradual increase in global temperatures caused by the emission of gases that trap the sun's heat in the Earth's atmosphere • The increase in the mean temperature of the earth due to excessive emissions of greenhouse gases such as carbon dioxide, methane, and nitrogen. • There are two major effects of global warming: • Increase of temperature on the earth by about 3° to 5° C (34° to 41° Fahrenheit) by the year 2100. • Rise of sea levels by at least 25 meters (82 feet) by the year 2100. EFFECTS OF WARMER ATMOSPHERE 78 On Water Resources Changes in water supply Decreased water quality Increased drought Increased flooding On Agriculture Shifts in food growing areas Changes in crop yields Increased irrigation yields Increased pests, crop diseases and weeds in warmer areas On Forests Changes in forest composition and locations Disappearance of some forests Increased fires from drying Loss of wildlife habitat and species On Biodiversity Extinction of some plant and animal species Loss of habitats CU IDOL SELF LEARNING MATERIAL (SLM)
Disruption of aquatic life On Sea Level and Coastal Areas Rising sea levels Flooding of low-lying islands and coastal cities Flooding of coastal estuaries, wetlands Beach erosion Disruption of coastal fisheries Contamination of coastal aquifers with salt water On Weather Prolonged heat waves and droughts Increased flooding from more frequent, intense and heavy rainfall in some areas On Human Population Increased deaths More environmental refugees Increased migration On Human Health Increased deaths from heat and disease Disruption of food and water supplies Spread of tropical diseases to temperate areas Increased respiratory disease and pollen allergies Increased water pollution PREVENTION OF GLOBAL WARMING • Cut fossil fuel use • Shift from coal to natural gas • Transfer energy efficiency and renewable energy technologies to developing countries • Shift to renewable energy resources • Reduce deforestation • Use sustainable agriculture • Limit urban sprawl • Reduce poverty • Slow population growth 3.6.3 Automobile Pollution Automobiles are a necessary evil, while they have made living easy and convenient, they have also made human life more complicated and vulnerable to both toxic emissions and an increased risk of accidents. 79 CU IDOL SELF LEARNING MATERIAL (SLM)
Sources of Automobile Pollutants Hydrocarbons: A class of burned or partially burned fuel, hydrocarbons are toxins and are a major contributor to smog, which can be a major problem in urban areas. Carbon monoxide: A product of incomplete combustion, carbon monoxide reduces the blood’s ability to carry oxygen. Nitrogen oxides (NOx):Generated when nitrogen in the air reacts with oxygen at the high temperature and pressure inside the engine. Particulate matter: Soot or smoke made up of particles in the micrometre size range Sulfur oxide (SOx): A general term for oxides of Sulphur, which are emitted from motor vehicles burning fuel containing a high concentration of Sulphur. Effects of Automobile Pollutants Prolonged exposure to hydrocarbons contributes to asthma, liver disease, and cancer, overexposure of carbon monoxide poisoning may be fatal. NOx is a precursor to smog and acid rain. NOx is a mixture of NO and NO2. NO2 destroys resistance to respiratory infection. Particulate matter causes negative health effects, including but not limited to respiratory disease. Oil, petroleum products and other toxins from automobiles kill fish, plants, aquatic life and even people. One quart of oil will contaminate thousands of gallons of water because it doesn’t dissolve. These toxins as well as trace metals and degreasing agents used on automobiles contaminate drinking water and can cause major illness. Some of these toxins and metals are absorbed in various sea life and cause medical problems to people when eaten. Control of Automobile Pollution: Engine efficiency has been steadily improved with improved engine design. One of the first-developed exhaust emission control systems is secondary air injection. Originally, this system was used to inject air into the engine’s exhaust ports to provide oxygen so unburned and partially-burned hydrocarbons in the exhaust would finish burning. Air injection is now used to support the catalytic converters oxidation reaction, and to reduce emissions when an engine is started from cold. After a cold start, an engine needs a fuel-air mixture richer than what it needs at operating temperature, and the catalytic converter does not function efficiently until it has reached its own operating temperature. 80 CU IDOL SELF LEARNING MATERIAL (SLM)
The air injected upstream of the converter supports combustion in the exhaust head pipe, which speeds catalyst warm up and reduces the amount of unburned hydrocarbon emitted from the tailpipe. Converter does not function efficiently until it has reached its own operating temperature. The air injected upstream of the converter supports combustion in the exhaust head pipe, which speeds catalyst warm up and reduces the amount of unburned hydrocarbon emitted from the tailpipe. The catalytic converter is a device placed in the exhaust pipe, which converts hydrocarbons, carbon monoxide, and NOx into less harmful gases by using a combination of platinum, palladium and rhodium as catalysts. Evaporative emissions control-Emissions are the result of gasoline vapours escaping from the vehicle’s fuel system. In a typical system, vapours from the fuel tank and carburetor bowl vent (on carbureted vehicles) are ducted to canisters containing activated carbon. The vapours are adsorbed within the canister, and during certain engine operational modes fresh air is drawn through the canister, pulling the vapour into the engine, where it is burned. 3.6.5 ACID RAIN • Acid rain is the common term used to describe wet, dry and fog deposition of sulfates and nitrates. When sulfur dioxide and nitrogen oxides are emitted through the burning of fossil fuels into the atmosphere, they come into contact with water where they are converted to sulfur and nitrogen-based acids, which can be as acidic as lemon juice. • WET DEPOSITION: Wet deposition refers to acidic rain, fog, and snow. If the acid chemicals in the air are blown into areas where the weather is wet, the acids can fall to the ground in the form of rain, snow, fog, or mist. • DRY DEPOSITION: In areas where the weather is dry, the acid chemicals may become incorporated into dust or smoke and fall to the ground through dry deposition, sticking to the ground, buildings, homes, cars, and trees. Dry deposited gases and particles can be washed from these surfaces by rainstorms, leading to increased runoff. Causes of Acid Rain Anthropogenic activities: • The primary causes of acid rain are sulfur dioxide and nitrogen oxides. • Most sulfur dioxide comes from power plants that use coal as their fuel. • Automobiles produce about half of the world's nitrogen oxide. As the number of automobiles in use increases, so does the amount of acid rain. • Power plants that burn fossil fuels also contribute significantly to nitrogen oxide emission. 81 CU IDOL SELF LEARNING MATERIAL (SLM)
Natural causes: • Fires, volcanic eruptions, bacterial decomposition, and lightening also greatly increase the amount of nitrogen oxide on the planet. Fig 3.3 Natural causes: Acid Formation in the Atmosphere • Carbonic acid forms naturally in the atmosphere due to the reaction of water (H2O) and carbon dioxide (CO2), H2O + CO2 -> H2CO3 • while the burning of coal and other organics adds sulfur dioxide (SO2) and Nitrous oxides (NOx) to the atmosphere where they react to form sulfuric acid and nitric acid, 2SO2 + H2O + O2 -> 2H2SO4 4NO2 + 2H2O + O2 -> 4HNO3 EFFECTS OF ACID RAIN • Acid rain has been shown to have adverse impacts on forests, freshwaters and soils, killing insect and aquatic life forms as well as causing damage to buildings and having impacts on human health. Surface Waters and Aquatic Animals • Both the lower pH and higher aluminum concentrations in surface water that occur as a result of acid rain can cause damage to fish and other aquatic animals. • At pHs lower than 5 most fish eggs will not hatch and lower pHs can kill adult fish. • As lakes and rivers become more acidic biodiversity is reduced. Soils 82 CU IDOL SELF LEARNING MATERIAL (SLM)
• Soil biology and chemistry can be seriously damaged by acid rain. Some microbes are unable to tolerate changes to low pHs and are killed. Forests and Other Vegetation • Adverse effects may be indirectly related to acid rain, like the acid's effects on soil (see above) or high concentration of gaseous precursors to acid rain. • High altitude forests are especially vulnerable as they are often surrounded by clouds and fog which are more acidic than rain. • The needles and leaves of the trees turn brown and fall off. • Trees can also suffer from stunted growth; and have damaged bark and leaves, which makes them vulnerable to weather, disease, and insects. Human Health • Fine particles, a large fraction of which are formed from the same gases as acid rain (sulfur dioxide and nitrogen dioxide), have been shown to cause illness and premature deaths such as cancer and other diseases. • One of the major problems that acid rain can cause in a human being is respiratory problems. • Many can find it difficult to breathe, especially people who have asthma. Asthma, along with dry coughs, headaches, and throat irritations can be caused by the sulphur dioxides and nitrogen oxides from acid rain. Effect of Acid Rain on Statues • Acid rain can also cause damage to certain building materials and historical monuments. This results when the sulfuric acid in the rain chemically reacts with the calcium compounds in the stones (limestone, sandstone, marble and granite) to create gypsum, which then flakes off. SOLUTIONS TO ACID RAIN • Industry can reduce acid rain creation by using coal with a low sulphur content, they can remove the sulphur from smoke their plants release, and they can limit processes known to generate high levels of acid rain • Sulphur dioxide can be removed from power stations chimneys but this process is expensive. • Reduce the amount of electricity we use turn tv’s off at the mains, don’t leave on standby. turn off lights when a room is not in use. • Use renewable energy like wind power, solar panels, tidal power, and geothermal energy. • Fit catalytic converters to vehicle exhausts which remove the nitrogen oxides. • Limit the number of vehicles on the roads and increase public transport. 83 CU IDOL SELF LEARNING MATERIAL (SLM)
3.6.6 OZONE LAYER DEPLETION Ozone • This is that oxygen zone, where oxygen is in the tri- molecular form (i.e.) O3 • Ozone is an irritating, corrosive, colorless gas with a smell something like burning electrical wiring. • \"The ozone layer\" refers to the ozone within stratosphere, where over 90% of the earth's • ozone resides. • This layer absorbs 93-99% of the sun's high frequency ultraviolet light, which is potentially damaging to life on earth. Good Ozone Ozone in the stratosphere provides a protective ozone layer that protects the earth from UV radiation. Oxygen gas (O2) + UVB --> 2 Oxygen(O) molecules Oxygen(O) + Oxygen gas (O2) --> “Good ozone” (O3) Absorbs incident UV radiation Bad Ozone Ozone lower in the atmosphere, at ground level in the air we breathe, is a pollutant. It is a health hazard and it can harm plants as well. “Bad ozone” is produced at ground-level (troposphere) Oxygen(O2) + Pollutants + UVB --> “Bad ozone” (O3) High levels toxic to living systems. Formation and Destruction Chapman reactions • Formation of ozone O2 + hν → O + O O + O2 → O3 O3 + hν → O2 + O O + O2 → O3 • Destruction of ozone CFCl3 + hν → CFCl2 + Cl Cl + O3 → ClO + O2 ClO + O3 → Cl + 2 O2 Ozone Layer Depleting Chemicals/Substances 84 Chlorofluorocarbons (CFCs) CU IDOL SELF LEARNING MATERIAL (SLM)
Carbon Tetrachloride (CCl4) Methyl Chloroform (CH3CCl3) Hydrochloric Acid (HCl) Methyl Chloride (CH3Cl) Methyl Bromide (CH3Br) Depletion of Ozone Layer • Chlorofluorocarbons are not \"washed\" back to Earth by rain or destroyed in reactions with other chemicals. They simply do not break down in the lower atmosphere and they can remain in the atmosphere from 20 to 120 years or more. • As a consequence of their relative stability, CFCs are instead transported into the stratosphere where they are eventually broken down by ultraviolet (UV) rays from the Sun, releasing free chlorine • The chlorine becomes actively involved in the process of destruction of ozone. Cl + O3 → ClO + O2 ClO + O → Cl + O2 Net reaction ClO + O3 → Cl + 2 O2 Factors affecting amount of UV radiation Position of sun (solar angle-altitude) Ozone layer thickness (“good ozone”) Aerosol (CFC) concentration Ground reflection (albedo) Altitude above sea level Cloud cover Atmospheric pollutants (CO, nitrous oxygen gases, “bad ozone”) Impacts of Ozone Layer Depletion • Impact on the oceans – Increasing amounts of UV radiation will have an impact on plankton and other tiny organisms at the base of the marine food web. These organisms provide the original food source for all other living organisms in the oceans. Plankton- phytoplankton as well as zooplankton are highly sensitive to UV radiation • Global warming – Ozone-layer depletion seems likely to increase the rate of greenhouse warming, by reducing the effectiveness of the carbon dioxide sink in the oceans. Phytoplankton in the oceans assimilates large amounts of atmospheric carbon dioxide. Increased UV radiation will reduce phytoplankton activity significantly 85 CU IDOL SELF LEARNING MATERIAL (SLM)
• Impact on land plants – Most plants (and trees) grow more slowly and become smaller and more stunted as adult plants when exposed to large amounts of UV-B. Increased UV-B inhibits pollen germination. • Increased effects of air pollution – UV-radiation causes many materials to degrade more rapidly. Plastic materials used outdoors will have much shorter lifetimes with small increases of UV radiation. • Damage to materials – Wood, plastic, rubber, fabrics and many construction materials are degraded by UV radiation. – The economic impact of replacing and/or protecting materials could be significant. Effects on Humans • More skin cancers, sunburns and premature aging of the skin. • More cataracts, blindness and other eye diseases: UV radiation can damage several parts of the eye, including the lens, cornea, retina and conjunctiva. • Weakening of the human immune system (immunosuppression). Too much UV radiation can suppress the human immune system, which may play a role in the development of skin cancer. Preventive Measures Using alternatives for CFCs Prevention of the emission of nitrous oxide To ban the use of depleting substances 3.7 ENVIRONMENTAL PROTECTION ACT • Environment Protection Act, 1986 is an Act of the Parliament of India. • In the wake of the Bhopal Tragedy, the Government of India enacted the Environment Protection Act of 1986 under Article 253 of the Constitution. • The Act is an “umbrella” legislation designed to provide a framework for central government coordination of the activities of various central and state authorities established under previous laws, such as the Water Act and the Air Act. Objectives • To co-ordinate the activities of the various regulatory agencies already in existence. 86 CU IDOL SELF LEARNING MATERIAL (SLM)
• Creation of an authority or authorities with adequate powers for environmental protection. • Regulation of discharge of environmental pollutants and handling of hazardous substance. • Speedy response in the event of accidents threatening environmental and deterrents punishment to those who endanger human environment, safety and health. Scheme of the Act • The Environment (Protection) Act, 1986 has 26 sections and it has been divided into four chapters relating to – Preliminary – General Powers of the Central Government – Prevention, Control, and Abatement of Environmental Pollution – Miscellaneous In this Act, unless the context otherwise requires- • “environment” includes water, air and land and the interrelationship which exits among and between water, air and land, and human beings, other living creature, plants microorganism and property; • “environment pollutant” means any solid, liquid or gaseous substance present in such concentration as may be, or tend to be injurious to environment. • “environment pollution” means the presence in the environment of any environmental pollutant. • “handling” in relation to any substance, means the manufacture, the processing, package, storage, transportation, use, collection, destruction, conversion, offering for sale, transfer or the like of such substance; • “hazardous substance” means any substance or preparation which by reason of chemical or physic-chemical properties or handling, is liable to cause harm to human beings, other living creature plants and micro-organism, property • “occupier” in relation to any factory or premise, means a person who has control over the affairs of the factory or the premises and includes, in relation to any substance, person in possession of the substance; • “prescribed” means prescribed by rules made under this Act. 3.8 WATER POLLUTION PREVENTION & CONTROL ACT • The objectives of the Water Act are to provide for the Prevention and Control of Pollution and the maintenance or restoration of the wholesomeness of water for the establishment, with a view to carrying out the purposes aforesaid, of Boards for the 87 CU IDOL SELF LEARNING MATERIAL (SLM)
prevention and control of water pollution, for conferring on and assigning to such Boards powers and functions relating thereto and for matters connected therewith. Objective • An Act to provide for the levy and collection of a cess on water consumed by persons carrying on certain industries and by local authorities, with a view to augment the resources of the Central Board and the State Boards for the prevention and control of water pollution constituted under the Water (Prevention and Control of Pollution) Act, 1974 • It extends to the whole of India except the State of Jammu and Kashmir In this Act, unless the context otherwise requires, - • (a)\"Board\" means the Central Board or a State Board; • (b) \"Central Board\" means the Central Pollution Control Board Constituted under section 3; • (c) \"member\" means a member of a Board and includes the chairman thereof; • (d) \"occupier\", in relation to any factory or premises, means the person who has control over the affairs of the factory or the premises, and includes, in relation to any substance, the person in possession of the substance; • (d) \"outlet\" includes any conduit pipe or channel, open or closed carrying sewage or trade effluent or any other holding arrangement which causes or is likely to cause, pollution; • (e) \"pollution\" means such contamination of water or such alteration of the physical, chemical or biological properties of water or such discharge of any sewage or trade effluent or of any other liquid, gaseous or solid substance into water (whether directly or indirectly) as may, or is likely to, create a nuisance or render such water harmful or injurious to public health or safety, or to domestic, commercial, industrial, agricultural or other legitimate uses, or to the life and health of animals or plants or of aquatic organisms; • (f) \"prescribed\" means prescribed by rules made under this Act by the Central Government or, as the case may be, the State Government; • (g) \"sewage effluent\" means affluent from any sewerage system or sewage disposal works and includes sullage from open drains; • (gg) \"sewer\" means any conduit pipe or channel, open or closed, carrying sewage or trade effluent; 88 CU IDOL SELF LEARNING MATERIAL (SLM)
• (h) \"State Board\" means a State Pollution Control Board constituted under section 4; • (i) \"State Government\" in relation to a Union territory means the Administrator thereof appointed under article 239 of the Constitution; • (j)\"stream\" includes- (i) river; (ii) water course (whether flowing or for the time being dry); (iii) inland water (whether natural or artificial); (iv) sub-terranean waters; (v) sea or tidal waters to such extent or, as the case may be, to such point as the State Government may, by notification in the Official Gazette, specify in this behalf; (k) \"trade effluent\" includes any liquid, gaseous or solid substance which is discharged from any premises used for carrying on any [Industry, operation or process, or treatment and disposal system], other than domestic sewage. 3.9 THE AIR (PREVENTION AND CONTROL OF POLLUTION) ACT, 1981 An Act to provide for the prevention, control and abatement of air pollution, for the establishment, with a view to carrying out the aforesaid purposes, of Boards, for conferring on and assigning to such Boards powers and functions relating thereto and for matters connected therewith. WHEREAS decisions were taken at the United Nations Conference on the Human Environment held in Stockholm in June, 1972, in which India participated, to take appropriate steps for the preservation of the natural resources of the earth which, among other things, include the preservation of the quality of air and control of air pollution; AND WHEREAS it is considered necessary to implement the decisions aforesaid in so far as they relate to the preservation of the quality of air and control of air pollution; (1) This Act may be called the Air (Prevention and Control of Pollution) Act, 1981. (2) It extends to the whole of India. (3) It shall come into force on such date as the Central Government may, by notification in the Official Gazette, appoint. (a) “air pollutant” means any solid, liquid or gaseous substance [(including noise)] present in the atmosphere in such concentration as may be or tend to be injurious to human beings or other living creatures or plants or property or environment; (b) “air pollution” means the presence in the atmosphere of any air pollutant; 89 CU IDOL SELF LEARNING MATERIAL (SLM)
(c) “approved appliance” means any equipment or gadget used for the bringing of any combustible material or for generating or consuming any fume, gas of particulate matter and approved by the State Board for the purposes of this Act; (d) “approved fuel” means any fuel approved by the State Board for the purposes of this Act; (e) “automobile” means any vehicle powered either by internal combustion engine or by any method of generating power to drive such vehicle by burning fuel; (f) “Board” means the Central Board or a State Board; (g) “Central Board” means the [Central Pollution Control Board] constituted under section 3 of the Water (Prevention and Control of Pollution) Act, 1974 (6 of 1974); (h) “chimney” includes any structure with an opening or outlet from or through which any air pollutant may be emitted; (i) “control equipment” means any apparatus, device, equipment or system to control the quality and manner of emission of any air pollutant and includes any device used for securing the efficient operation of any industrial plant; (j) “emission” means any solid or liquid or gaseous substance coming out of any chimney, duct or flue or any other outlet; (k) “industrial plant” means any plant used for any industrial or trade purposes and emitting any air pollutant into the atmosphere; (l) “member” means a member of the Central Board or a State Board, as the case may be, and includes the Chairman thereof; (m) “occupier”, in relation to any factory or premises, means the person who has control over the affairs of the factory or the premises, and includes, in relation to any substance, the person in possession of the substance; (n) “prescribed” means prescribed by rules made under this Act by the Central Government or, as the case may be, the State Government; 3.10 SALIENT FEATURES OF ENVIRONMENTAL SUMMIT – PARIS 2015 The 2015 United Nations Climate Change Conference, COP 21 or CMP 11 was held in Paris, France, from 30 November to 12 December 2015. It was the 21st yearly session of the Conference of the Parties (COP) to the 1992 United Nations Framework Convention on Climate Change (UNFCCC) and the 11th session of the Meeting of the Parties (CMP) to the 1997 Kyoto Protocol. 90 CU IDOL SELF LEARNING MATERIAL (SLM)
On 12 December 2015, the participating 196 countries agreed, by consensus, to the final global pact, the Paris Agreement, to reduce emissions as part of the method for reducing greenhouse gas. In the 12-page document, the members agreed to reduce their carbon output \"as soon as possible\" and to do their best to keep global warming \"to well below 2 degrees C\". In the course of the debates, island states of the Pacific, the Seychelles, but also the Philippines, their very existence threatened by sea level rise, had strongly voted for setting a goal of 1.5 °C instead of only 2 °C. France's Foreign Minister, Laurent Fabius, said this \"ambitious and balanced\" plan was an \"historic turning point\" in the goal of reducing global warming. However, some others criticized the fact that significant sections are \"promises\" or aims and not firm commitments by the countries 3.11 SUMMARY Water Pollution is defined as alteration in the physical, chemical or biological characteristics of water, making it unsuitable for intended use in its natural state. Land pollution is the degradation of the Earth's land surface through misuse of the soil by poor agricultural practices, mineral exploitation, industrial waste dumping, and indiscriminate disposal of urban wastes. Noise pollution is displeasing human or machine created sound that disrupts the activity or happiness of human or animal life. Air pollution is defined as the excessive concentration of foreign matter in the air which adversely affects the wellbeing of the individual or causes damage to the property. Global warming is the gradual increase in global temperatures caused by the emission of gases that trap the sun's heat in the Earth's atmosphere Automobiles are a necessary evil, while they have made living easy and convenient, they have also made human life more complicated and vulnerable to both toxic emissions and an increased risk of accidents. Acid rain is the common term used to describe wet, dry and fog deposition of sulfates and nitrates. When sulfur dioxide and nitrogen oxides are emitted through the burning of fossil fuels into the atmosphere, they come into contact with water where they are converted to sulfur and nitrogen-based acids, which can be as acidic as lemon juice. Salient features of Environmental Protection Act, Water Act, Air Act 91 CU IDOL SELF LEARNING MATERIAL (SLM)
3.12 LEARNING ACTIVITY 1. Collect data on the air quality index of your city over past decade. Discuss and analyze the possible causes for change. ___________________________________________________________________________ ___________________________________________________________________________ 2. Collect data on the availability of surface water sources suitable for drinking in your district. ___________________________________________________________________________ ___________________________________________________________________________ 3.13UNIT END QUESTIONS A.Descriptive Questions Short Questions 1. Differentiate primary and secondary pollutants. 2. State the impacts of carbon monoxide on human health? 3. Name two water borne diseases. 4. How is noise controlled in the transmission path? 5. List the major greenhouse gases. Long Questions 1. Discuss the causes and effects of land pollution. 2. Explain in detail the measures adopted to control air pollution. 3. Write short notes on: Ozone Layer Depletion, Global Warming 4. Elucidate the causes and effects of acid rain? 5. Give the salient features of Air (Prevention and Pollution) Act. B. Multiple Choice Questions 1. Carbon dioxide is primarily called a greenhouse gas because a. Trap’s heat b. Trap’s light c. Traps warm currents d. None of the above 2. What are two acids formed when gases react with the tiny droplets of water in clouds? a. Sulphuric acids and nitric acid b. Hydrochloric acid and nitric acid 92 CU IDOL SELF LEARNING MATERIAL (SLM)
c. Sulfurous acid and acetylsalicylic acid d. Sulphuric acid and hydrochloric acid 3. Which of the following is not a waterborne disease? a. Measles b. Typhoid c. Cholera d. Hepatitis 4. Depletion of the ozone layer is damaging to human health. Negative effects include a. Skin cancers b. Osteoporosis c. Dyspepsia d. Diarrhea 5. Which one of the following is a result of climate change? a. Adequate rainfall b. Pure air c. Deficiency of freshwater d. Less soil pollution Answer 1-a, 2-a, 3-a, 4-a, 5-c 3.14 REFERENCES Reference Books Erach Bharucha, “Textbook of Environmental Studies” University Press India Pvt. Ltd., Hyderabad, 2015. G. Tyler Miller, Jr. and Scott E. Spoolman “Environmental Science” Thirteenth Edition, Cengage Learning, 2010. Gilbert M. Masters and Wendell P. Ela “Introduction to Environmental Engineering and Science‟, 3rd edition, Pearson Education, 2013 93 CU IDOL SELF LEARNING MATERIAL (SLM)
UNIT-4: DISASTER MANAGEMENT Structure 4.0 Learning Objectives 4.1 Introduction 4.2 Types of Disasters 4.3 Classification of Natural Disasters 4.4 Floods 4.4.1 Distribution of Floods in India 4.4.2 Consequences of Floods 4.4.3 Control of Floods 4.5 Cyclones 4.5.1 Structure of Tropical Cyclones 4.5.2 Spatio-Temporal Distribution of Tropical Cyclones in India 4.5.3 Consequences of Tropical Cyclones 4.6 Earthquakes 4.6.1 Seismic Zones of India 4.6.2 Measurement of Earthquakes 4.6.3 Socio-Economic Consequences of Earthquakes 4.6.4 Earthquake Hazard Mitigation 4.7 Landslides 4.7.1 Landslides Prone Regions of India 4.7.2 Consequences of Landslides 4.7.3 Mitigation of Landslides 4.8 Summary 4.9 Keywords 4.10 Learning Activity 4.11Unit end Questions 4.12 References 4.0 LEARNING OBJECTIVES After learning this unit students will be able to: Classify and characterize a disaster based on its nature. Illustrate the causes, consequences, control mitigation measures of natural disasters. 94 CU IDOL SELF LEARNING MATERIAL (SLM)
4.1 INTRODUCTION A Disaster is an undesirable occurrence resulting from forces that are largely outside human control, strikes quickly with little or no warning, which causes or threatens serious disruption of life and property including death and injury to a large number of people, and requires therefore, mobilization of efforts in excess of that which are normally provided by statutory emergency services. A disaster takes place when the following three conditions occur at the same time: When people live in hazardous places like, for example, close to an active volcano, on unstable slopes where landslides are likely to happen, or close to rivers which could flood. When a hazardous phenomenon occurs, be it natural or human-made. When the phenomenon also causes a lot of damage, especially where no preventive measures have been taken. 4.2 TYPES OF DISASTERS Natural Disasters According to the International Federation of Red Cross & Red Crescent Societies Natural Disasters are naturally occurring physical phenomena caused either by rapid or slow onset events that have immediate impacts on human health and secondary impacts causing further death and suffering. These disasters can be: Geophysical (e.g., Earthquakes, Landslides, Tsunamis and Volcanic Activity) Hydrological (e.g., Avalanches and Floods) Climatological (e.g., Extreme Temperatures, Drought and Wildfires) Meteorological (e.g., Cyclones and Storms/Wave Surges) Biological (e.g., Disease Epidemics and Insect/Animal Plagues) The United Nations Office for Disaster Risk Reduction characterizes Natural Disasters in relation to their magnitude or intensity, speed of onset, duration and area of extent e.g., earthquakes are of short duration and usually affect a relatively small region whereas droughts are slow to develop and fade away and often affect large regions. Man-Made Disasters Man-Made Disasters as viewed by the International Federation of Red Cross & Red Crescent Societies are events that are caused by humans which occur in or close to human settlements often caused as a result of Environmental or Technological Emergencies. This can include: Environmental Degradation Pollution 95 CU IDOL SELF LEARNING MATERIAL (SLM)
Accidents (e.g., Industrial, Technological and Transport usually involving the production, use or transport of hazardous materials) Complex Emergencies Some disasters can result from multiple hazards, or, more often, to a complex combination of both natural and man-made causes which involve a break-down of authority, looting and attacks on strategic installations, including conflict situations and war. These can include: Food Insecurity Epidemics Armed Conflicts Displaced Populations According to International Committee of Red Cross (ICRC) these Complex Emergencies are typically characterized by: Extensive Violence Displacements of Populations Loss of Life Widespread Damage to both Societies and Economies Need for Large-scale, Humanitarian Assistance across Multiple Agencies Political and Military Constraints which impact or prevent Humanitarian Assistance Increased Security Risks for Humanitarian Relief Workers Pandemic Emergencies Pandemic (from Greek πᾶν pan \"all\" and δῆμος demos \"people\") is an epidemic of infectious disease that has spread across a large region, which can occur to the human population or animal population and may affect health and disrupt services leading to economic and social costs. It may be an unusual or unexpected increase in the number of cases of an infectious disease which already exists in a certain region or population or can also refer to the appearance of a significant number of cases of an infectious disease in a region or population that is usually free from that disease. Pandemic Emergencies may occur as a consequence of natural or man-made disasters. These have included the following epidemics: Ebola Zika Avian Flu Cholera Dengue Fever Malaria Yellow Fever 96 CU IDOL SELF LEARNING MATERIAL (SLM)
Coronavirus Disease (COVID-19) 4.2 CLASSIFICATION OF NATURAL DISASTERS Table 4.1 Classification of Natural Disasters Atmosphere Terrestrial Aquatic Biological Blizzards Thunderstorms Earthquakes Floods Plant and Animals as Lightning colonizers (Locusts, Tornadoes Volcanic Eruptions Tidal Waves etc.) Tropical Cyclones Drought Landslides Ocean Currents Insects Infestation - Hailstorm Fungal, Bacterial and Avalanches Storm Surge Viral diseases such as Frost Bird Flu, Dengue, etc. Subsidence Tsunami Heat Waves Cold Waves Soil Erosion Wild Fires 4.4 FLOODS The inundation of land and human settlements by the rise of water in the channels and its spill-over presents the condition of flooding. Unlike other natural disasters, the causes of floods are well established. Floods are relatively slow in occurrences and often, occur in well-identified regions and within expected time in a year. Floods occur commonly when water in the form of surface run-off exceeds the carrying capacity of the river channels and streams and flows into the neighbouring low-lying flood plains. At times, this even goes beyond the capacity of lakes and other inland water bodies in which they flow. Floods can also be caused due to a storm surge (in the coastal areas), high intensity rainfall for a considerably longer time period, melting of ice and snow, reduction in the infiltration rate and presence of eroded material in the water due to higher rate of soil erosion. Though floods occur frequently over wide geographical area having disastrous ramifications in many parts of the world, floods in the South, Southeast and East Asian countries, particularly in China, India and Bangladesh, are frequent and equally disastrous. 97 CU IDOL SELF LEARNING MATERIAL (SLM)
Human beings play an important role in the genesis as well as spread of floods. Indiscriminate deforestation, unscientific agricultural practices, disturbances along the natural drainage channels and colonization of flood-plains and river-beds are some of the human activities that play an important role in increasing the intensity, magnitude and gravity of floods. 4.4.1 Distribution of Floods in India Various states of India face heavy loss of lives and property due to recurrent floods. Rashtriya Barh Ayog (National Flood Commission) identified 40 million hectares of land as flood-prone in India. Assam, West Bengal and Bihar are among the high flood-prone states of India. Apart from these, most of the rivers in the northern states like Punjab and Uttar Pradesh, are also vulnerable to occasional floods. It has been noticed that states like Rajasthan, Gujarat, Haryana and Punjab are also getting inundated in recent decades due to flash floods. This is partly because of the pattern of the monsoon and partly because of blocking of most of the streams and river channels by human activities. Sometimes, Tamil Nadu experiences flooding during November-January due to the retreating monsoon. Figure 4.1 Map Showing Flood Prone Areas in India 98 CU IDOL SELF LEARNING MATERIAL (SLM)
4.4.2 Consequences of Flood Frequent inundation of agricultural land and human settlement, particularly in Assam, West Bengal, Bihar and Eastern Uttar Pradesh (flooding rivers), coastal areas of Orissa, Andhra Pradesh, Tamil Nadu and Gujarat (cyclone) and Punjab, Rajasthan, Northern Gujarat and Haryana (flash floods) have serious consequences on the national economy and society. Floods do not only destroy valuable crops every year but these also damage physical infrastructure such as roads, rails, bridges and human settlements. Millions of people are rendered homeless and are also washed down along with their cattle in the floods. Spread of diseases like cholera, gastro-enteritis, hepatitis and other water-borne diseases spread in the flood-affected areas. However, floods also make a few positive contributions. Every year, floods deposit fertile silt over agricultural fields which are good for the crops. Majuli (Assam), the largest riverine island in the world, is the best example of good paddy crops after the annual floods in Brahmaputra. But these are insignificant benefits in comparison to the grave losses. 4.4.3 Control of Flood The Government of India as well as the state governments are well aware of the menace created by floods every year. Construction of flood protection embankments in the flood-prone areas, construction of dams, afforestation and discouraging major construction activities in the upper reaches of most of the flood-creating rivers, etc. are some steps that need to be taken up on urgent basis. Removal of human encroachment from the river channels and depopulating the flood plains can be the other steps. This is particularly true in western and northern parts of the country which experience flash-floods. Cyclone centres may provide relief in coastal areas which are hit by a storm surge. 4.5 CYCLONES Tropical cyclones are intense low-pressure areas confined to the area lying between 30° N and 30° S latitudes, in the atmosphere around which high velocity winds blow. Horizontally, it extends up to 500-1,000 km and vertically from surface to 12-14 km. A tropical cyclone or 99 CU IDOL SELF LEARNING MATERIAL (SLM)
hurricane is like a heat engine that is energized by the release of latent heat on account of the condensation of moisture that the wind gathers after moving over the oceans and seas. Some initial conditions for the emergence of a tropical cyclone are: Large and continuous supply of warm and moist air that can release enormous latent heat. Strong Coriolis force that can prevent filling of low pressure at the center (absence of Coriolis force near the equator prohibits the formation of tropical cyclone between 0°- 5°latitude). Unstable condition through the troposphere that creates local disturbances around which a cyclone develops. Finally, absence of strong vertical wind wedge, which disturbs the vertical transport of latent heat. Figure 4.2 The Coriolis Effect 4.5.1 Structure of Tropical Cyclone Tropical cyclones are characterized by large pressure gradients. The centre of the cyclone is mostly a warm and low-pressure, cloudless core known as ‘eye’ of the storm. 100 CU IDOL SELF LEARNING MATERIAL (SLM)
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