Environment Pollution -Water pollution & Air Pollution (Unit 2)

Environment Pollution

"Environment" is most commonly used describing "natural" environment and means the sum of all living and non-living things that surround an organism, or group of organisms. Environment includes all elements, factors, and conditions that have some impact on growth and development of certain organism.

Environment includes both biotic and abiotic factors that have influence on an organism. Abiotic factors such as light, temperature, water, atmospheric gases combine with biotic factors (all surrounding living species). In other words Environment is the surrounding atmosphere/ condition required for existence of a living being.

Pollution is the introduction of contaminants into an environment that causes instability, disorder, harm or discomfort to the ecosystem i.e. physical systems or living organisms. Pollution can take the form of chemical substances or energy, such as noise, heat, or light.

Environmental Pollution is “the contamination of the physical and biological components of the earth/atmosphere system to such an extent that normal environmental processes are adversely affected”. It may also be described as any discharge of material or energy into water, land, or air that causes or may cause acute (short-term) or chronic (long-term) detriment to the Earth's ecological balance or that lowers the quality of life.

Pollutants may cause primary damage, with direct identifiable impact on the environment, or secondary damage in the form of minor perturbations in the delicate balance of the biological food web that are detectable only over long time periods.

Part 1: Water Pollution

Water is a precious natural resource for survival and health of living organisms. Water pollution means presence of any foreign substance (organic, inorganic, radiological and biological) in the water, which tend to degrade its quality so as to constitute a hazard or impair the usefulness of water.  Water pollution is a major problem associated with the developing countries. It severely affects the lives of people.

 

Water Sources of India

India accounts for about 2.45 per cent of world’s surface area, 4 per cent of the world’s water resources and about 16 per cent of world’s population. The total water available from precipitation in the country in a year is about 4,000 cubic km. The availability from surface water and replenishable groundwater is 1,869 cubic km. Out of this only 60 per cent can be put to beneficial uses. Thus, the total utilisable water resource in the country is only 1,122 cubic km.

Water is one of nature's most important gifts to mankind. Essential to life, a person's survival depends on drinking water. Although water covers more than 70% of the Earth, only 1% of the Earth's water is available as a source of drinking. Yet, our society continues to contaminate this precious resource.

1. Ground Water: Most of the fresh water on land is not in river and lakes. It is hidden underground in spaces between soil and rock particles as ground water. The total replenishable groundwater resources in the country are about 432 cubic km. The Ganga and the Brahamaputra basins, have about 46 per cent of the total replenishable groundwater resources. The level of groundwater utilisation is relatively high in the river basins lying in north-western region and parts of south India. The groundwater utilisation is very high in the states of Punjab, Haryana, Rajasthan, and Tamil Nadu. However, there are States like Chhattisgarh, Odisha, Kerala, etc., which utilise only a small proportion of their groundwater potentials.

2. Surface Water: After precipitation, the amount of water that does not percolate down into the ground or does not return to the atmosphere as evaporation or transpiration and enters the river, streams, lakes, ponds, wetland or artificial reservoirs constitutes surface water. In the country, there are about 10,360 rivers and their tributaries longer than 1.6 km each. The mean annual flow in all the river basins in India is estimated to be 1,869 cubic km.

 

Following are some of the uses of Water:

Agriculture: It is estimated that 69% of worldwide water use is for irrigation. In some areas of the world irrigation is necessary to grow any crop at all, in other areas it permits more profitable crops to be grown or enhances crop yield. Irrigation methods considered to be more efficient include drip or trickle irrigation, surge irrigation, and some types of sprinkler systems where the sprinklers are operated near ground level. These types of systems, while more expensive, usually offer greater potential to minimize runoff, drainage and evaporation. As global populations grow, and as demand for food increases in a world with a fixed water supply, there are efforts underway to learn how to produce more food with less water, through improvements in irrigation methods and technologies, agricultural water management, crop types, and water monitoring.

Industrial: It is estimated that 22% of worldwide water use is industrial. Major industrial users include power plants, which use water for cooling or as a power source (i.e. hydroelectric plants), ore and oil refineries, which use water in chemical processes, and manufacturing plants, which use water as a solvent. Industry requires pure water for many applications and utilizes a variety of purification techniques both in water supply and discharge.

Household: It is estimated that 8% of worldwide water use is for household purposes. These include drinking water, bathing, cooking, sanitation, and gardening. Drinking water is water that is of sufficiently high quality so that it can be consumed or used without risk of immediate or long term harm. Such water is commonly called potable water. In most developed countries, the water supplied to households, commerce and industry is all of drinking water standard even though only a very small proportion is actually consumed or used in food preparation.

Environmental: Explicit environmental water use is also a very small but growing percentage of total water use. Environmental water usage includes artificial wetlands, artificial lakes intended to create wildlife habitat, fish ladders, and water releases from reservoirs timed to help fish spawn. Environmental usage is non-consumptive but may reduce the availability of water for other users at specific times and places. For example, water release from a reservoir to help fish spawn may not be available to farms upstream.

Hydrological Cycle (Water Cycle):

The Hydrologic Cycle (also called the Water Cycle) is the continuous movement of water in the air, on the surface of and below the Earth. This cycle is the exchange of energy which influences climate. When water condenses, it releases energy and warms the environment. When water evaporates it takes energy from the surrounding environment, dropping temperatures.

 

The hydrologic cycle begins with the evaporation of water from the surface of the ocean. As moist air is lifted, it cools and water vapor condenses to form clouds. Moisture is transported around the globe until it returns to the surface as precipitation.

Methods or ways of Water Conservation and Management

• Over the years rising populations, growing industrialization, and expanding agriculture have pushed up the demand for water.
• Clean, usable water has become scarce these days.
• The solution lies in conserving water, water recycling and harvesting of rain water more efficiently.
• Efforts have been made to collect water by building dams and reservoirs and digging wells; some countries have also tried to recycle and desalinate (remove salts) water.
• Water conservation has become the need of the day.
• Water conservation can be defined as reducing the usage of water and recycling of waste water for different purposes such as cleaning, manufacturing, and agricultural irrigation.
• In urban areas, the construction of houses, footpaths and roads has left little exposed earth for water to soak in.
• In parts of the rural areas of India, floodwater quickly flows to the rivers, which then dry up soon after the rains stop.
• If this water can be held back, it can seep into the ground and recharge the groundwater supply.
• This method of water conservation is gaining momentum rapidly.

Rain Water Harvesting:

• Rainwater harvesting essentially means collecting rainwater on the roofs of building and storing it underground for later use
• This recharging not only arrests ground water depletion, but also raises the declining water table and helps augment water supply.
• Rainwater harvesting and artificial recharging are becoming very important issues.
• It is essential to stop the decline in groundwater levels, arrest sea-water ingress, i.e. prevent sea-water from moving landward, and conserve surface water run-off during the rainy season.
• Rainwater harvesting has some advantages like

ü   Increases water availability.

ü  Checks the declining water table.

ü  Is environmentally friendly

ü  Improves the quality of groundwater through the dilution of fluoride, nitrate, and salinity.

ü  Prevents soil erosion and flooding especially in urban areas.

Why Rain Water Harvesting?

Rainwater Harvesting is essential because:

1. Surface water is inadequate to meet our demand and we have to depend on ground water.

2. Due to rapid urbanization, infiltration of the rain water into the sub-soil has decreased drastically and recharging of ground water has diminished.

 

Rain Water Harvesting as a Government Policy:

The Government has been promoting the adoption of ‘Rainwater harvesting’ as a mass movement. ‘Rainwater Harvesting’ is also an important component for achieving the goals of ‘Water Security’. ‘Shelter Security’ and ‘Ecological Security’ enunciated in the Hon’ble Chief Minister’s 15 Point programme. Universal adoption of Rainwater Harvesting by government departments, Non- Governmental organizations (NGOs) and people would go a long way in improving the ground water levels in the states as well as in meeting the immediate requirements of the people for fresh water. Considerable success has been achieved in propagating the beneficial effects of Rainwater Harvesting and the Government departments, NGOs, industries and individuals are now involved in this task of Rainwater Harvesting. Several government departments have issued separate guidelines for the implementation of Rainwater Harvesting by their respective departments. It is, therefore, considered necessary, at this stage, to issue comprehensive guidelines to coordinate the activities of various agencies involved in Rainwater Harvesting to maximize the benefits and bring about synergy.

 

Legislative Measures (Legal Aspects):

ü  The Chennai Metropolitan Development Authority, all Municipal corporations, Municipalities, Towns Panchayats and the Directorate of town and Country planning shall approve by layout plans, building plans, etc., and leases of all building plans for new buildings only after confirming the inclusion of provision of Rainwater Harvesting structure in the proposed plans.

ü  In the case of existing buildings efforts should be made by local body authorities to ensure that Rainwater Harvesting structures are put up in the buildings at the earliest.

ü  No building or structure with roof shall be given permission for construction in the state, henceforth, without adequate provision for Rainwater Harvesting.

ü  Water connection and Sewer connection shall not be given to any building which does not have Rainwater Harvesting structure.

ü  Building that does not provide for Rainwater Harvesting either in urban or rural areas shall not be hereafter assessed to property tax.

ü  Huts and thatched structures put up by families living below the poverty line shall be exempted from the above provisions.

 

Rainwater Harvesting by the Public:

ü  Both persuasive and legislative measures shall be used for ensuring the provision of Rainwater Harvesting structures in all buildings.

ü  Information, Education and Communication (IEC):

ü  IEC is an important component in persuading public to adopt Rainwater Harvesting. As they are the direct beneficiaries of these structures, more information dissemination will be sufficient to make them construct Rainwater structures. While the Chennai Metropolitan Water Supply and Sewage Board will be the nodal agency for the IEC campaign within the Chennai Metropolitan area, the respective district collectors shall coordinate the IEC activities in the districts.

 

Watershed Management:

·         Watershed can be defined as an extent or area of land where water from rain and melting snow or ice drains downhill into a body of water, such as a river, lake, reservoir, or ocean.

·         It acts as a funnel by collecting all the water within the area covered by the basin and channeling it into a waterway.

·         It is also termed as “catchment area”.

 

River Action Plan:

The water quality data generated through National Water Monitoring Programme and River Basin Studies carried out since, 1980 indicated deterioration of water quality in riverine segments and other water bodies. The water bodies not meeting the desired water quality criteria are identified as polluted river stretches/water bodies. The deviation of water quality from the desired water quality criteria in the data generated for the river Ganga formed the basis for launching Ganga Action Plan (GAP). Subsequently, the river stretches not meeting the desired criteria are identified in all the major river basins. The identified polluted river stretches were intensively surveyed by State Pollution Control Boards (SPCBs) and Central Pollution Control Board (CPCB) to identify the sources of pollution such as Urban Centres and Industrial Units.

National River Conservation Directorate (NRCD) is implementing the River Action Plans for restoration of water quality based on the findings of survey reports submitted by CPCB/SPCBs. The thrust of NRCD is towards providing funds to state agencies for interception, diversion and treatment of sewage discharged to the water bodies from identified Urban Centers. At present NRCD is implementing the Action Plans in 157 cities and towns located along 30 rivers. The name of the rivers are Adyar, Cooum, Betwa, Bhadra, Brahmani, Cauvery, Chambal, Damodar, Ganga, Godavari, Gomti, Khan, Krishna, Kshipra, Mahanadi, Mandovi, Narmada, Pennar, Sabarmati, Satluj, Subarnarekha, Tapti, Tunga, Tungbhadra, Tambiraparni, Vennar, Vaigai, Walnganga, Yamuna and Musi.

Ganga Action Plan (GAP)

The Ganga action plan was, launched by Shri Rajeev Gandhi, the then Prime Minister of India on 14 Jan. 1986 with the main objective of pollution abatement, to improve the water quality by Interception, Diversion and treatment of domestic sewage and present toxic and industrial chemical wastes from identified grossly polluting units entering in to the river. The other objectives of the Ganga Action Plan are as under.

• Control of non-point pollution from agricultural runoff, human defecation, cattle wallowing and throwing of unburnt and half burnt bodies into the river.
• Research and Development to conserve the biotic, diversity of the river to augment its productivity.
• New technology of sewage treatment like Up-flow Anaerobic Sludge Blanket (UASB) and sewage treatment through afforestation has been successfully developed.
• Rehabilitation of soft-shelled turtles for pollution abatement of river have been demonstrated and found useful.
• Resource recovery options like production of methane for energy generation and use of aquaculture for revenue generation have been demonstrated.
• To act as trend setter for taking up similar action plans in other grossly polluted stretches in other rivers.

The ultimate objective of the GAP is to have an approach of integrated river basin management considering the various dynamic inter-actions between abiotic and biotic eco-system.

Not with standing, some delay in the completion of the first phase of GAP it has generated considerable interest and set the scene for evolving a national approach towards replicating this program for the other polluted rivers of the country. The Government of India proposed to extend this model with suitable modifications to the national level through a National River Action Plan (NRAP). The NRAP mainly draws upon the lessons learnt and the experience gained from the GAP besides seeking the views of the State Governments and the other concerned Departments/Agencies.

Under NRCP scheme the CPCB had conducted river basin studies and had identified 19 gross polluted stretches and 14 less polluted stretches along 19 rivers, which include 11 stretches situated along 7 rivers of M.P. 

 

Yamuna Action Plan (YAP)

Yamuna Action Plan (YAP) to clean the dirtiest river of the country was formally launched in 1993. The YAP has so far completed two phases as YAP-I and YAP-II. The YAP-I covered Delhi, eight towns in Uttar Pradesh and six towns in Haryana. Under YAP II, emphasis was on the 22-km stretch of Yamuna in Delhi. Now we have YAP-III, at an estimated cost of Rs 1,656 crore. 

The Yamuna Action Plan (YAP) is a bilateral project between the Government of India and Japan. It is one of the largest river restoration projects in India. The government of Japan, via the Japanese Bank for International Cooperation (JBIC), has provided financial aid of 17.7 billion to carry out the project, which is being executed by the National River Conservation Directorate, the Ministry of Environment and Forests, and the Government of India.

 

Sources of Water (Ground and Surface) Pollution:

  

ü  Sedimentation – It is caused by soil particles that enter the water as a result of runoff from agricultural land, forests, overgrazed grasslands and construction sites. Sediment pollution causes problems by reducing light penetration, covering aquatic organisms, bringing insoluble toxic pollutants into the water and filling waterways. The suspended particles make the water turbid. Disease causing agents can also be transported into water via sediments.

ü  Sewage - Sewage water pollution is one of the  major problems in cities. The sewage water is drained off into rivers without treatment. The careless disposal of sewage water leads to a chain of problems, such as spreading of diseases. Improper handling of waste water is the main reason behind the pollution of water. The sewage is drained off in large quantities into rivers. It slows down the process of dilution of the constituents present in the water; which in turn, stagnates the river.

ü  Draining off the water without treatment is also a reason behind sewage water pollution. These effluents contain innumerable pathogens and harmful chemicals. The detergents that release phosphates in water help the growth of algae and water hyacinths.

ü  Disease causing agents – municipal waste water contains many bacteria, viruses and other infectious agents which causes many diseases like typhoid, cholera, infectious hepatitis etc.

ü  Inorganic Plant Nutrients – fertilizers runoff from agricultural lands which are a major contributor of Inorganic plant nutrients. Inorganic plant nutrients such as nitrogen, phosphorus encourage excessive growth of algae and aquatic plants which disturbs the natural balance, thus causing problems such as bad odor, low oxygen in water etc.

ü  Industrial Waste Water – waste water produced by industries which is contaminated by organic pollutants. This water is then discharged in the rivers, thus polluting them. Most of the industrial effluents released in the water are non-degradable in nature.

ü  Organic Chemicals – synthetic chemicals such as pesticides, solvents, industrial chemicals and plastics.

ü  Inorganic Chemicals – industrial plants, oil drilling are some activities that release inorganic chemicals into the water. Mercury is one of the important inorganic chemical causing long term impact on kidney and nervous system.

ü  Radioactive substances- sources such as mining and processing of radioactive minerals, nuclear power plants contaminate water with radioactive substances.

ü  Thermal pollution – many industries like power plants, oil refineries use water as coolant for the machinery. Release of hot water, having 8-10degree higher temperatures than the intake water causes pollution. 

Effects of Water Pollution:

ü  A number of waterborne diseases are produced by the pathogens present in polluted water, affecting humans and animals alike.

ü  Pollution affects the chemistry of water. The pollutants, including toxic chemicals, can alter the acidity, conductivity and temperature of water.

ü  As per the records, about 14000 people perish or incur various communicable diseases due to the consumption of contaminated drinking water.

ü  The concentration of bacteria and viruses in polluted water causes increase in solids suspended in the water body, which, in turn, leads to health problems.

ü  Marine life becomes deteriorated due to water pollution. Lethal killing of fish and aquatic plants in rivers, oceans and seas is an aftereffect of water contamination only.

ü  Diseases affecting the heart, poor circulation of blood and the nervous system and ailments like skin lesion, cholera and diarrhea are often linked to the harmful effects of water pollution.

ü  Carcinogenic pollutants found in polluted water might cause cancer.

ü  Alteration in the chromosomal makeup of the future generation is foreseen, as a result of water pollution.

ü  Discharges from power stations reduce the availability of oxygen in the water body, in which they are dumped.

ü  The flora and fauna of rivers, sea and oceans is adversely affected by water pollution.

Measures to Control Water Pollution:

ü  Control water pollution in your home by using non-toxic soaps, detergents and cleaning products. Refrain from the use of chemical fertilizers and pesticides on your lawn and gardens. Always dispose of paints, motor oil, gasoline, antifreeze and other harmful chemicals in accordance with your local laws and safety regulations.

ü  Protect groundwater, which is critical for drinking water, irrigation systems and natural ecosystems. If you are using chemicals that may be harmful to the environment, store them correctly. Improperly stored chemicals can slowly seep into the groundwater system, so keep them in tightly sealed containers, inside of structures with cement floors, to avoid groundwater contamination.

ü  Prevent polluted runoff and soil erosion. Polluted runoff is caused when rain washes toxic pollutants into surface waters from sources that include city streets, farms, or logging and mining sites. Plant bushes and trees along roads and natural water sources. The roots of trees and bushes can slow the speed of runoff and erosion, protecting surface water.

ü  Write letters to your state representative and congressman to express your concerns about water pollution. Ask them to promote more sustainable agricultural methods and mention that you feel it is time for Congress to create and enforce stricter mandatory laws regarding water pollution.

Waste Water Management:

Wastewater treatment is the process of converting wastewater – water that is no longer needed or is no longer suitable for use – into bilge water that can be discharged back into the environment. It’s formed by a number of activities including bathing, washing, using the toilet, and rainwater runoff. Wastewater is full of contaminants including bacteria, chemicals and other toxins. Its treatment aims at reducing the contaminants to acceptable levels to make the water safe for discharge back into the environment.

There are two wastewater treatment plants namely chemical or physical treatment plant, and biological wastewater treatment plant. Biological waste treatment plants use biological matter and bacteria to break down waste matter. Physical waste treatment plants use chemical reactions as well as physical processes to treat wastewater. Biological treatment systems are ideal for treating wastewater from households and business premises. Physical wastewater treatment plants are mostly used to treat wastewater from industries, factories and manufacturing firms. This is because most of the wastewater from these industries contains chemicals and other toxins that can largely harm the environment.

“Wastewater treatment is a process to convert wastewater – which is water no longer needed or suitable for its most recent use – into an effluent that can be either returned to the water cycle with minimal environmental issues or reused. The latter is called water reclamation and implies avoidance of disposal by use of treated wastewater effluent for various purposes.” (According to Wikipedia,)

 

Step by Step Wastewater Treatment Process

1. Wastewater Collection: This is the first step in waste water treatment process. Collection systems are put in place by municipal administration, home owners as well as business owners to ensure that all the wastewater is collected and directed to a central point. This water is then directed to a treatment plant using underground drainage systems or by exhauster tracks owned and operated by business people. The transportation of wastewater should however be done under hygienic conditions. The pipes or tracks should be leak proof and the people offering the exhausting services should wear protective clothing.

2. Odor Control: At the treatment plant, odor control is very important. Wastewater contains a lot of dirty substances that cause a foul smell over time. To ensure that the surrounding areas are free of the foul smell, odor treatment processes are initiated at the treatment plant. All odor sources are contained and treated using chemicals to neutralize the foul smell producing elements. It is the first wastewater treatment plant process and it’s very important.

3. Screening: This is the next step in wastewater treatment process. Screening involves the removal of large objects for example nappies, cotton buds, plastics, diapers, rags, sanitary items, nappies, face wipes, broken bottles or bottle tops that in one way or another may damage the equipment. Failure to observe this step, results in constant machine and equipment problems. Specially designed equipment is used to get rid of grit that is usually washed down into the sewer lines by rainwater. The solid wastes removed from the wastewater are then transported and disposed off in landfills.

4. Primary Treatment: This process involves the separation of macrobiotic solid matter from the wastewater. Primary treatment is done by pouring the wastewater into big tanks for the solid matter to settle at the surface of the tanks. The sludge, the solid waste that settles at the surface of the tanks, is removed by large scrappers and is pushed to the center of the cylindrical tanks and later pumped out of the tanks for further treatment. The remaining water is then pumped for secondary treatment.

5. Secondary Treatment: Also known as the activated sludge process, the secondary treatment stage involves adding seed sludge to the wastewater to ensure that is broken down further. Air is first pumped into huge aeration tanks which mix the wastewater with the seed sludge which is basically small amount of sludge, which fuels the growth of bacteria that uses oxygen and the growth of other small microorganisms that consume the remaining organic matter. This process leads to the production of large particles that settle down at the bottom of the huge tanks. The wastewater passes through the large tanks for a period of 3-6 hours.

6. Bio-solids handling: The solid matter that settle out after the primary and secondary treatment stages are directed to digesters. The digesters are heated at room temperature. The solid wastes are then treated for a month where they undergo anaerobic digestion. During this process, methane gases are produced and there is a formation of nutrient rich bio-solids which are recycled and dewatered into local firms. The methane gas formed is usually used as a source of energy at the treatment plants. It can be used to produce electricity in engines or to simply drive plant equipment. This gas can also be used in boilers to generate heat for digesters.

7. Tertiary treatment: This stage is similar to the one used by drinking water treatment plants which clean raw water for drinking purposes. The tertiary treatment stage has the ability to remove up to 99 percent of the impurities from the wastewater. This produces effluent water that is close to drinking water quality. Unfortunately, this process tends to be a bit expensive as it requires special equipment, well trained and highly skilled equipment operators, chemicals and a steady energy supply. All these are not readily available.

8. Disinfection: After the primary treatment stage and the secondary treatment process, there are still some diseases causing organisms in the remaining treated wastewater. To eliminate them, the wastewater must be disinfected for at least 20-25 minutes in tanks that contain a mixture of chlorine and sodium hypochlorite. The disinfection process is an integral part of the treatment process because it guards the health of the animals and the local people who use the water for other purposes. The effluent (treated waste water) is later released into the environment through the local water ways.

9. Sludge Treatment: The sludge that is produced and collected during the primary and secondary treatment processes requires concentration and thickening to enable further processing. It is put into thickening tanks that allow it to settle down and later separates from the water. This process can take up to 24 hours. The remaining water is collected and sent back to the huge aeration tanks for further treatment. The sludge is then treated and sent back into the environment and can be used for agricultural use.

Part 2: Air Pollution

Air Pollutants: An air pollutant is known as a substance in the air that can cause harm to humans and the environment. The Air (Prevention and Control of Pollution) Act, 1981, defined Air Pollutant as any solid, liquid or gaseous substance(including noise) present in the atmosphere in such a concentration as may be injurious to human health or other living creatures or plants or property or environment.

Sources of Air Pollution (Air Pollutants):

ü  Sulphur Di Oxide - It is a chemical compound produced by industrial processes. Since coal and petroleum often contain sulfur compounds, their combustion generates sulfur dioxide. Its combination with moisture results in Acid Rains which are very harmful to living organisms. This is one of the causes for concern over the environmental impact of the use of these fuels as power sources.

ü  Nitrogen Oxide - are emitted from high temperature combustion in Factories. This reddish-brown toxic gas has a characteristic sharp, biting odor. NO₂ is one of the most prominent air pollutants.

ü  Carbon Monoxide- It is a colorless, odorless, non-irritating but very poisonous gas. It is a product by incomplete combustion of fuel such as natural gas, coal or wood. Vehicular exhaust is a major source of carbon monoxide.

ü  Volatile Organic Compounds - VOCs are an important outdoor air pollutant. Methane is an extremely efficient greenhouse gas which contributes to enhance global warming. The aromatic compounds benzene, toluene and xylene are suspected carcinogens and may lead to leukemia through prolonged exposure.

ü  Particulate Matter - Particulates, alternatively referred to as particulate matter (PM) or fine particles, are tiny particles of solid or liquid suspended in a gas. In contrast, aerosol refers to particles and the gas together. Sources of particulate matter can be manmade or natural. Some particulates occur naturally, originating from volcanoes, dust storms, forest and grassland fires, living vegetation, and sea spray. Human activities, such as the burning of fossil fuels in vehicles, power plants and various industrial processes also generate significant amounts of aerosols. Increased levels of fine particles in the air are linked to health hazards such as heart disease, altered lung function and lung cancer.

ü     Chlorofluorocarbons - CFC’s are harmful to the ozone layer, resulting in depletion of ozone.

ü  Ammonia - emitted from agricultural processes. It is normally encountered as a gas with a characteristic pungent odor. Ammonia contributes significantly to the nutritional needs of terrestrial organisms by serving as a precursor to foodstuffs and fertilizers. Although in wide use, ammonia is both caustic and hazardous.

ü    Odors - such as from garbage, sewage, and industrial processes.

ü  Radioactive Pollutants - produced by nuclear explosions, war explosives, and natural processes such as the radioactive decay of radon.

    

Effects of Air Pollution on Human Health and Vegetations:

·         Air pollution can affect our health in many ways with both short-term and long-term effects.

·         Different groups of individuals are affected by air pollution in different ways.

·         Young children and elderly people often suffer more from the effects of air pollution.

·         People with health problems such as asthma, heart and lung disease may also suffer more when the air is polluted.

·      Irritation to the eyes, nose and throat, and upper respiratory infections such as bronchitis, pneumonia, headaches, nausea, and allergic reactions are some Short-term effects of air pollution.

·   Short-term air pollution can aggravate the medical conditions of individuals with asthma and emphysema.

·     Long-term health effects can include chronic respiratory disease, lung cancer, heart disease, and even damage to the brain, nerves, liver, or kidneys.

·    Continual exposure to air pollution affects the lungs of growing children and may aggravate or complicate medical conditions in the elderly.

 

Measures to control air pollution may be as follows:

The fact is that human activities contribute the most to air pollution. Considering the harmful effects of air pollution, now it is very essential that everyone should contribute a bit to prevent air pollution. There are certain ways that one can help to reduce the emission of air pollutants in the atmosphere.

 

Tips for Preventing Air Pollution:

ü  Car Pool: Forming and implementing a car pool will reduce the number of cars, thereby, preventing air pollution by cutting down the use of fossil fuels. This way, it will help in the sustainable use of fossil fuel and its conservation for the future generations.

ü  Vehicle Care: Timely servicing of the car helps to keep it in a good condition and also minimizes fuel exhaust. Driving the car at an average speed and turning off in traffic is a key to save fuel. Make sure to use unleaded petrol and opt for regular pollution checking of the car.

ü  Public Transport: Whenever possible, try to travel by public transports. This helps in two ways; prevents air pollution and increases public income. If you are going to a nearby place, go by walking or use bicycle, instead of using your vehicle. The objective is to minimize the use of fuels, as far as possible.

ü  Alternative Energy Source: Another effective way to prevent air pollution is to use alternative energy sources such as solar energy, hydroelectric energy and wind energy. Nowadays, sophisticated technologies such as wind turbine, solar water heaters are introduced to generate electricity and other energy forms for the household use.

ü  Saving Energy: Saving energy will, of course, help to prevent air pollution. Switch off the lights, fans, air conditioners, televisions, and other appliances, when not in use. You can also share a room with others when the air conditioner or fan is on, instead of switching them on in every room.

ü  Minimize Air Pollutants: Always try to minimize smoke emission, as it can contribute to air pollution. One way is to compost dried leaves and kitchen waste, instead of burning them. Composting will also give you organic fertilizer for your garden. While buying the products, always choose air-friendly and recyclable products that will minimize the emission of pollutants.

ü  Social awareness: Social Awareness about air pollution is the most essential step to be taken for the prevention of air pollution. Awareness programs and/or advertisements should be encouraged, so that people understand the potential health hazards of air pollution. Improvement of transport facilities and proper use of land for the sake of social benefits are equally important for controlling air pollution.

Greenhouse effect:

The greenhouse effect is a natural process that warms the Earth’s surface. When the Sun’s energy reaches the Earth’s atmosphere, some of it is reflected back to space and the rest is absorbed and re-radiated by greenhouse gases. Greenhouse gases include water vapour, carbon dioxide, methane, nitrous oxide, ozone and some artificial chemicals such as chlorofluorocarbons (CFCs).The absorbed energy warms the atmosphere and the surface of the Earth. This process maintains the Earth’s temperature at around 33 degrees Celsius warmer than it would otherwise be, allowing life on Earth to exist. The steps involve in this effect are:

Step 1: Solar radiation reaches the Earth's atmosphere - some of this is reflected back into space.

Step 2: The rest of the sun's energy is absorbed by the land and the oceans, heating the Earth.

Step 3: Heat radiates from Earth towards space.

Step 4: Some of this heat is trapped by greenhouse gases in the atmosphere, keeping the Earth warm enough to sustain life.

Step 5: Human activities such as burning fossil fuels, agriculture and land clearing are increasing the amount of greenhouse gases released into the atmosphere.

Step 6: This is trapping extra heat, and causing the Earth's temperature to rise.

Enhanced greenhouse effect

The problem we now face is that human activities – particularly burning fossil fuels (coal, oil and natural gas), agriculture and land clearing – are increasing the concentrations of greenhouse gases. This is the enhanced greenhouse effect, which is contributing to warming of the Earth.

Global Warming and Climate Change:

ü  Human activities involving industrialization and population growth has greatly increased the demand of energy.

ü  This has resulted in massive increase in the consumption of fossil fuels.

ü  Burning of fossil fuels results in CO2 emissions on a larger scale.

ü  Yet another reason for the increase of CO2 is the growing deforestation.

ü  This is the main reason behind Global Warming.

ü   Global warming and climate change refer to an increase in average global temperatures.

ü  Natural events and human activities are believed to be contributing to an increase in average global temperatures.

ü  The erratic climatic changes and persistent problem of global warming has lead to several environmental, economic and social problems.

ü  Environmental problems such as dangerously increasing levels of sea level, scarcity of rainfall, reduction in fresh water availability have been observed.

ü  If the global warming continues to be on the rise, it will cause reduction in the production of crops, thus affecting the agricultural revenues adversely.

ü  Majority of the people are for whom climate change will mean hunger, food insecurity, and destruction of livelihoods, thus threatening the social security of the people.