As we all know that environmental degradation caused by over exploitation of natural resources and decline in the quality and/or quantity of environment may result from the alteration of the entire structure of the resources as in land degradation, deforestation, etc.
So, our main objectives of this article is to describe the cause of environmental pollution, list of air, water and land pollution and their sources, consequences of air pollution, water pollution, and land pollution, options available for pollution control.
WHAT IS POLLUTION:
Pollution occurs when a substance present in the environment prevents the functioning of natural process and produces considerable environmental and health effects, In the natural world, many substances accumulating in the environment are processed through the intricate network of bio- geochemical cycles.
Pollution is defined as any undesirable change in the physical, chemical or biological characteristics of environmental components, i.e, air, water, and soil that adversely affects the life forms and life support systems of the biosphere directly or indirectly.
The agents that contaminates the environmental component is called the pollutant.
A normal constituent of the environment becomes a pollutant if its concentration increases beyond the acceptable limits, destroying its usefulness. A pollutant is also a new substance (biotic or abiotic) or energy ( heat, sound, radioactivity etc) that is added to or formed in any component of the environment and builds up to a level where usefulness of that component is damaged.
Pollutant can be grouped into two broad categories:
- NON BIODEGRADABLE
Non Biodegradable Pollutants are those pollutants which are not broken down or decomposed by bacteria. Examples are pesticides, heavy metals etc. Plastics also fall in the same category. These pollutants persist for a very long time in nature, get accumulated and often bio magnify to a dangerous level when they move in material cycles in the nature and along with the food chain.
Biodegradable Pollutants such as garden waste, domestic sewage, etc, break down into simple products by bacterial decomposition process. These simple products are raw materials of nature that are reutilised in the ecosystem. Decomposition of these non-persistent pollutants occurs naturally as well as through engineered systems such as sewage treatment plants. Such man made systems enhance nature’s capacity to decompose. These biodegradable pollutants pose a threat when their input in the environment exceeds the decomposition capacity.
Pollutants may have different kinds of effects on human beings as well as on other components of biosphere. The reasons for this are the difference in the chemistry and concentration of the pollutants. In some cases the combined effect of substances may be greater than the sum of the effects of individual substances.
Moving on to the pollutions types now:
Air is essential to live. We can live without food and water for days but only a few minutes without oxygen. When clean air moves in the troposphere, it collects products from natural events as well as human activities. Some of these pollute the air.
Suspended particulate matter, bio particles, smoke, mist, fumes, spray, NO, NO2, SO2, CO, CO2, O3, PAN, HF, NH3, Cl, H2S, etc
Air pollutants can be grouped into two categories: PRIMARY POLLUTANTS and SECONDARY POLLUTANTS.
Primary Pollutants are emitted directly into the air as a result of natural or human activity, whereas Secondary Pollutants are produced as a result of chemical reactions between primary pollutants and normal atmospheric compounds under the influence of solar radiations. Eg of primary pollutants are ozone, hydrocarbons etc and eg of secondary pollutants are ozone, smoke, acid rain etc.
Acute health effect and Chronic health effects like asthma, emphysema are the main problem from air pollution.
Any Physical, chemical or biological change that degrades the water quality results in water pollution. Water being a universal solvent can dissolve various types of substances in it. Due to this property, contamination of water becomes inevitable.
Industrial effluents, agricultural runoffs, municipality and domestic waste and substances produced from the energy production and warfare are the major land based sources of water pollution due to human activities.
Water pollutants are divided into 3 major categories: biological, chemical and physical.
Biological agents are pathogenic organisms like viruses, bacteria etc. Chemical pollutants can be water soluble, water insoluble or oxygen demanding water. Eg, gasoline, pesticides etc. Physical agents include the factors like suspended solids, sedimentary solids, and temperature, that affect the quality of water.
LAND AND SOIL POLLUTION:
Land pollution are mainly of 3 types, Domestic wastes, Substances that accumulate on land due to agricultural activities, and, Industrial activities. Some of these are hazardous, particularly hospital waste and some persistent pesticides.
Peoples participation in environmental protection:
The success of India’s environmental programmes depends greatly on the awareness and consciousness of the people. A national Environmental Awareness Campaign has been launched to sensitize people to the environmental problems through audio-visual programmes, seminars, training programmes etc.
INDIA AND GLOBAL ENVIRONMENTAL POLLUTION CONTROL EFFORTS:
India has played a significant role in the global environmental campaign. It has participated actively in the various environmental conferences and programmes launched since the UNEP conference held in Stockholm in 1972.
We hope that you have now become well aware of the dangers to our environment and some ways to combat them. We expect that, empowered with this understanding, you will be able to contribute your mite in whatever way possible to make this world a safer place to live in.