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| Summary |
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 Environment is defined as the surroundings in which the organism lives. It has two components - abiotic and biotic. |
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 The abiotic environment includes the air (atmosphere), water (hydrosphere) and land (lithosphere). The biotic environment includes the plants, animals and the microbes. |
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 The things that man requires for his survival and comfort are called the resources. So, the environment, with respect to man, is a reservoir of his resources. |
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 Maintaining the natural resources of the environment and their careful use is called conservation. |
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 The resources may be classified into living and non-living resources. |
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 The living resources include the plants, animals and the microbes. |
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 The non-living resources include the air, water, energy, minerals, etc. |
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| Soil is considered a mixed resource. |
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 The resources may also be classified into renewable and non-renewable. |
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 Renewable resources include resources like the solar energy, air, plants, animals and microbes. |
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 Non-renewable resources include fossil fuels such as coal and petroleum and most of the minerals. |
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 A healthy environment is an absolute necessity for the well-being of all organisms, including man. However, man's thoughtless actions are creating environmental problems. |
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| Some of them are: |
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 Pollution which is defined as 'undesirable change in the physical, chemical or biological characteristics of air, water and land brought about by man's activities that may harmfully affect living organisms and other resources'. |
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 Based on the environmental component being polluted there are three types of pollution - air, water and soil. |
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 Air pollution can be defined as 'the alteration of the composition of air by the addition of harmful substances like the industrial and automobile gases and particulate matter.' |
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 The sources of air pollution are burning of fossil fuels, automobiles, industries like the fertiliser plants, thermal plants, textile industries, steel plants, etc., volcanic eruptions, anaerobic decomposition of municipal and organic waste, atmospheric and oceanic reactions. |
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 The substances that actually cause pollution are called the pollutants. There are six main categories of air pollutants- oxides of carbon, sulphur dioxide, oxides of nitrogen, hydrocarbons, organic particulate matter, inorganic particulate matter and aerosols |
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| Some of the effects of air pollution are: |
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| Global warming- due to which temperatures are going up every year. |
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 Formation of photochemical smog formed when pollutants like hydrocarbons and nitrogen oxides combine in the presence of sunlight. It hampers visibility and causes respiratory problems. |
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 Formation of acid rain that causes many skin and respiratory problems. Depletion of ozone that protects us from the harmful effects of the UV rays. |
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 Air pollution can be controlled by different methods depending on the source and the pollutant. Some of the methods used are good quality fuel, vehicles running on alternate sources of energy, detoxification and removal of sulphur from industrial gases before being released, using solar cookers or bio gas, planting of trees that remove the polluting gases and clean the atmosphere and creating public awareness about the ill-effects of air pollution. |
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 Water pollution is a major problem associated with the developing countries. |
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 Its sources are sewage that includes organic matter, industries, agricultural chemicals, oil spill, etc. |
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 The major pollutants are the organic matter of the sewer, metallic substances and other inorgaic chemicals from the industries, hot water, oil, inorganic fertilizers and pesticides. |
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 Some of the effects of water pollution are eutrophication (enrichment of water) causing oxygen depletion, biomagnification (the accumulation of nonbiodegradable chemicals in the animals bodies in large quantities), epidemics like cholera, gastroenteritis, etc. |
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 Control of water pollution is mainly by sewage treatment, effluent treatment and public awareness. |
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 Soil is an important resource as it is the basis for the growth of plants which are the producers. However, in the recent times soil has been subject to pollution from different sources. |
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 The sources that are polluting soil are pesticides, acid rains, improper disposal of garbage, industrial, radioactive substances and night soil |
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 Some of the measures that can control soil pollution are suitable and safe disposal of wastes, recycling of non-biodegradable materials like plastic, glass, metals, etc. and replacing inorganic pesticides by organic pesticides. |
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 Population explosion is one of the most serious problems faced by the developing countries. Increase in population has resulted in strain on the resources. |
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 Soil erosion - The removal of this topsoil is called soil erosion. Soil erosion results in the loss of soil fertility and makes the land barren. It also leads to desertification. |
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 The main cause of soil erosion is the removal of vegetation. The removal of vegetation exposes the topsoil to water and wind |
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 Water erosion - Removal of topsoil by water is called water erosion. The different types of water erosion are sheet erosion, rill erosion, gully erosion, riparian erosion and soil leaching. |
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 Wind erosion - The fast moving wind moves the fine particles to other places. The deserts are encroaching the fertile areas in this manner. |
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 Prevention and control of soil erosion can be done by increase of vegetation, restoring soil fertility, control of grazing, terracing, dam building and wind breakers. |
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 Another of environmental problem is global warming - It is the heating of the earth with increasing temperatures every year. The gases that contribute to global warming are also called the greenhouse gases. |
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 Accumulation of wastes - Accumulation of wastes due to its improper disposal is a major problem in our country. |
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| In the absence of proper solid waste management, this waste lies littered on our streets, road corners and improperly disposed of in vacant land. All of these are serious health hazards apart from being eyesores. They increase numbers of insect vectors like flies, mosquitoes, etc., scavengers such as stray dogs, pigs and rats which spread dangerous diseases. It also generates bad odour and causes pollution. |
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| The wastes can be classified into: |
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 Biodegradable - The biodegradable wastes are those that can be decomposed. For example, kitchen garbage, animal dung, etc. |
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 Non-biodegradable - The non-biodegradable wastes are those that cannot be decomposed and remain as such in the environment. For example, plastics, nuclear wastes, glass, etc. |
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 Some of these wastes are also classified as hazardous wastes. Hazardous wastes are those that catch fire easily, react explosively with air or water, corrodes other materials, are toxic or radioactive. |
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 Waste management involves collection, storage, transportation, recycling and disposal. |
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 Loss of wildlife - Precious plants and animals are becoming extinct or endangered as a result of clearing of the forests. |
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 Conservation of wildlife is being done by the following measures - protecting and improving the natural habitat, proper management of water resources, creating national parks and wildlife sanctuaries for safe breeding of the endangered, enacting strict laws and creating public awareness. |
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 The food chains and other such interrelationships in the ecosystems create a balance in the environment that is called the ecological balance. However, man tries to modify the environment to suit his needs. This has upset the delicate balance being maintained in the environment. |
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 Sustainable development is defined as "a process of change in which the exploitation of resources, the direction of investments, the orientation of technological development and the institutional change are in harmony and enhance both current and future generations to meet their needs." |
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 This concept means that there is a symbiotic relationship (mutually beneficial) between the developmental process and environment protection. |
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 There is an interrelationship of population, environment and development. As a result of increase in population, there is a strain on the environment. Unplanned and short-sighted development plans also harm the environment. Since the environment that can sustain the increasing populations has to be created, it is important that conservation of environment is given equal if not more concern than development. |
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 The governments of different countries must contribute towards conservation and protection of the environment by making strict legislations to counter the activities that are not environment friendly and lead to unsustainable development. |
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 Towards this, the government has enacted various laws from time to time. |
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