Guru
Introduction
Pollution is a global problem that poses a significant threat to our environment and human health. It results from the release of pollutants into the air, water, soil, and ecosystems, disrupting the natural balance and causing a range of detrimental effects. In this blog post, we will explore what pollution is, the various types of pollutants, their sources, and the far-reaching consequences they have on our planet.
Pollution is the introduction of harmful or undesirable substances into the environment, often in greater quantities than the environment can naturally accommodate or safely assimilate. Pollution can take various forms, including chemical, biological, and physical, and it affects air, water, soil, and living organisms. It is a direct consequence of human activities, industrialization, and urbanization.
Pure air is colourless and odourless while pure water is colourless,tasteless and odourless. But these properties are affected by external substances from natural or man-made sources.
This is the phenomenon of pollution and the external substances are known as pollutants.Thus air is polluted due to presence of carbon monoxide, nitrogen oxide etc. from vehicular emissions.Similarly water gets polluted by waste from domestic sewage, industrial sewage etc.
Pollutants are contributed by natural and man-made sources. Natural sources of air pollution are: volcanic activity, vegetation decay, forest fires emitting carbon monoxide,sulphur dioxide, particles of solids or liquids sprayed from the seas, and land by wind.
Man-made sources of air pollution are: gases, mists, particles and aerosols emitted by industries and other chemical and biological processes used by man.
Natural sources of water pollution are: soil erosion, particles from atmosphere, vegetation decay etc.Man-made sources of water pollution are: domestic and industrial sewage, agricultural run-off, radioactive wastes, hot water from power plants, oil pollution, pesticides etc.
Types of Pollutants
- Gaseous pollutants: Nitrogen oxides (NOx), sulfur dioxide (SO2), carbon monoxide (CO) ozone (O3).
- Particulate matter: Fine and coarse particles (PM2.5 and PM10 ground).
- Volatile organic compounds (VOCs).
- Chemical pollutants: Lead, mercury pesticides,pharmaceuticals and industrial chemicals.
- Biological pollutants: Bacteria, viruses, harmful algal blooms.
- Nutrient pollutants: Fertilizers and wastewater represent nitrogen and phosphorus.
- Heavy metals: Lead, cadmium, arsenic.
- Organic pollutants: Pesticides, herbicides, and industrial chemicals.
- Soil erosion and sedimentation.
- Noise pollution: Noise pollution due to too much traffic, industrial activity and city-building.
- Light pollution: Light pollution from too much artificial light wrecks natural rhythms of light and dark.
Sources of Pollution
The sources of pollution are diverse and can be attributed to various human activities and natural processes:
1. Industrial Activities: Air and water pollutants are a result of the operations yields of factories, power plants and manufacturing plants.
2. Transportation: Other sources of the pollutants include cars, vans, trucks and others kinds of vehicles such as ships and aeroplanes which release gases like CO2, NOx and particulates.
3. Agricultural Practices: Pesticide, fertilizer, and animal waste production or release creates water and soil pollution.
4. Waste Disposal: Improper processing of solid waste such as landfilling and burning generates volatile chemicals that negatively impact the environment.
5. Construction and Urbanization: The soil and water pollution associated with construction activities can emerge in the run off of sediment or chemicals.
6. Deforestation and Land-Use Changes: Land use and deforestation affects the vitality of ecosystems inadvertently causing pollution.
Effects of Pollution
1. Air Pollution: Air pollution has some of the most serious repercussions such as respiratory diseases,cardiovascular problems and climate change.
2. Water Pollution: The provenance of polluted water supply that has the potential to cause health problems, disrupted ecosystems and lessen clean water results in.
3. Soil Pollution: Contamination of soil negatively affects not only plant life but also reduces the productive output, which has implications for food security.
4. Noise and Light Pollution: Such types of pollution can mess up sleep rhythms, influence how wildlife interacts with the environment and cause harm to human welfare.
5. Biodiversity Loss: Pollution also causes the destruction of ecosystems as plants and animals lose their habitats thereby losing species and altering the ecological balance.
MAN-NATURE INTERACTION
Man is at the centre of the biosphere in dynamic equilibrium with other segments of the environment—air, water and land. His daily life is heavily dependent on his natural environment—he gets food from soil, fruits and timber from trees, medicines from plants, meat from birds and animals, fish from ponds, rivers and seas, water for daily use from springs, rivers and ground water.
Indian Tradition: India has a rich tradition in environmental ethics. Ancient Indians used to worship Nature—sun, water, air, soil, plants and animals. The ancient philosophers believed that the entire universe including earth, plants, animals and human beings is made of five essential elements viz. kshiti (earth), op (water), teja (fire or energy), marut (air) and byom (open space). Bodies of plants, animals and human beings are created out of these five essential elements and after death and decay, their bodies are disintegrated and converted back to these elements.
The fundamentals of conservation ethics were brilliantly formulated in the IshoUpanishad during the Vedic era. “The whole universe together with all its creatures belong to the Lord (Nature). Let no one species encroach over the rights and privileges of other species. Man can enjoy the bounties of Nature by giving up greed.” In other words, if we over-exploit Nature, we shall lose all the benefits from Nature.
In the Maurya period the emperors emphasised the awareness campaign for conservation of Nature and upholding the spirit of non-violence towards trees and animals.Compassion for animate and inanimate objects is part and parcel of Indian culture.But unfortunately we have forgotten this basic philosophy and turned to Western culture of conflict with Nature.
Scan of Human Civilization: It is worthwhile to scan human civilization since man’s arrival on earth. Primitive man lived in mountain caves and looked at the forces of Nature with wonder and awe. He was panicky about the sun, lightning, thunder, rains and also wild animals in the forests. He was constantly busy in protecting himself and his family against the hostile elements around him. Gradually he discovered fire and made stone tools for his defense against wild animals. About 10,000 years ago agriculture was discovered and that was the starting point for human civilization.
In course of time man devised science and technology step by step and depended on these for improving his living standard. This became prominent after the Industrial Revolution (1760-1840) which transformed England from an agricultural country into a predominantly industrial one. The invention of steam engine by James Watt (1785), mechanisation in textile industry, advancement in mining, transport and ship-building industries made Britain the most prosperous country in the world. This was promoted by British colonial exploitation.
With the help of science and technology, man overcame the natural barriers and established his supremacy over Nature. He can travel from one part of the world to the other part, in a matter of a few hours, undertake journey to outer space and planets, dive down to the bottom of seas and explore the wonders there and so on. But at the same time, the environment became more and more degraded and polluted. As a result of man-made activities (deforestation urbanisation, industrialisation, etc.) the quality of environment suffered which has threatened the survival of man himself on earth.
NATURAL AND MAN-MADE CHANGES IN ENVIRONMENT AND DISASTERS
Natural Changes in Environment
The environment is always subject to changes and these changes will continue in future.When life first appeared, there was no oxygen in the atmosphere which was full of carbon dioxide and other gases including water vapour. This primitive climate changed very slowly;it took over 2 billion years to accumulate enough oxygen in the atmosphere which helped in the evolutions of life forms (aerobic organisms).
Most of the oxygen in the atmosphere today has come from water through the photosynthetic activities of green plants. Such change is natural (non-anthropogenic) but it altered the chemical composition of air which led to other changes in the environment. From oxygen of the atmosphere ozone was formed which slowly passed into the stratosphere where it served as a protective umbrella of ozone layer.The latter protects life on earth by absorbing the harmful ultraviolet radiator from the sun.
Continental drifting is an important part of natural changes. The continents were not stationary but they were slowly drifting apart. The entire outer shell of the earth is made up of huge tectonic plates1 which float on the molten fluid core of the earth. Initially the continents were all joined together forming a single landmass - later on they drifted very slowly.This movement is the phenomenon of continental drift.
The continents have drifted for about 2500 million years and the annual rate of drifting is 20 to 75 mm. Such movement can cause splitting of part of a continent forming oceans such as the Atlantic Ocean, seas such as the Red Sea and lakes such as Lake Baikal. Collision of one tectonic plate with another can cause earthquakes, volcanic explosions and formation of mountains. Collision of Indian plate with Asian plate gave rise to the world’s highest mountain, our Himalayas some 50 million years ago.
The earth’s environment also passed through drastic changes in average temperature of the earth’s surface creating the Ice Ages. During the earth’s history the temperature fluctuated between relatively stable states about 30 times due to earth’s rotation on its axis and changes in the sun’s activity. The last Ice Age was about 18,000 years ago when a vast sheet of ice advanced from the North Pole covering Canada, Greenland and up to U.K. including the North Sea. As the ice moved back, vast quantities of cold water flooded the Atlantic disturbing the ocean currents. The Ice Age was over by 3000 B.C. and normal temperature slowly restored.
Natural Disasters
The environment has undergone sweeping changes by natural disasters viz. cyclone,typhoon, hurricane, tornado, earthquake, volcanic eruptions etc. The latter have caused enormous damages on lives and properties.
Cyclone, typhoon and hurricane, are the same weather phenomenon occurring in different regions of the world. Cyclones are storms that originate in the Indian Ocean and bring about extensive flood and damage in the Indian sub-continent including Sri Lanka and Mynamar. Typhoons are storms in the Pacific Ocean which cause havoc in South-East Asia while those in the North Atlantic Ocean that destroy South East USA are hurricanes. Hurricanes arise from tropical seas when the latter are warmed by the solar heat. They are powered by the heat released when the rising water vapour condenses.Most of the hurricane’s energy is used to lift the airmass at the centre of the storm.Hurricanes, typhoons are in the form of spiralling air column which can have a speed of over 250 km/hr., uprooting big trees, tearing off house roofs, lifting people, cattle, cars and sucking almost anything on their path. They can whip up high waves on the surface of seas, oceans as sea level is raised as high as 8 m or 25 ft. This can cause flash floods along the coastal region. They are also accompanied by torrential rains in the region.
The earthquakes have a rather high frequency, about 100 earthquakes/hr all over the world. But most of them are of low magnitudes. The earthquake-prone zones in the world encircle the Pacific Ocean (Zone1) and on the other side, stretch from Spain, Turkey,Northern Mediterranean to Japan, Himalayas and Indonesia (Zone 2). These two zones meet near New Guinea (North of Australia). The earth’s outer crust is divided into seven large tectonic plates and in between them there are more than 20 smaller plates. The plates move slowly over a partially molten mass of metals and minerals–they often converge,collide and sometimes one plate slips below another plate releasing tremendous energy in the form of seismic waves that shake the ground violently. This causes earthquake.
The intensity of an earthquake is measured on Richter scale (1 Richter is the minimum intensity detectable on the instrument, Seismograph). The earthquake at Bhuj, Gujarat(2000 A.D.) measured 6.0 on the Richter scale. It destroyed the entire city of Bhuj and killed most of its population–its destructive force was equivalent to more than 100 Hiroshima-type atomic bombs.
Volcanoes sometimes erupt with devastating power, throwing molten lava, silicate dust and sulphuric acid into the atmosphere. When Mt. Pinatubo in the Philippines erupted in 1991, it increased the dust content of the atmosphere to more than 50 times its normal level. As a result, Indonesia, Malayasia missed summer in 1991.
Man-Made (Anthropogenic) Changes in Environment and Disasters
Primitive man looked at Nature with wonder and awe because of its terrible forces as manifested from time to time as lightning, thunder, cyclone, volcanic eruption, flash flood, landslides, etc.
In his constant efforts for better living standards, man developed science and technology over the years. The Industrial Revolution of 1780 was a landmark in the history of human civilization. It started with the invention of steam engine (James Watt) in England. By 1840 England was transformed from an agricultural country into a predominantly industrial one. Textile, mining, transport and ship-building industries were developed. Manchester,Newcastle, Birmingham and Glasgow became major industrial cities of Britain. The Industrial Revolution along with colonial rule made Britain the most prosperous country in the world in the 19th century.
With development of science and technology, man continued to plunder natural resources and pollute the environment. He destroyed forests, degraded lands, threw toxic wastes into rivers and seas and also harmful gases into the atmosphere.The continuous load of pollutants into the environment brought about changes in it which ultimately backfired into series of disasters from time to time. Several man-made disasters may be mentioned below. All these killed people and made generations to suffer from genetic and other disorders.