Domestic sewage is the waste originating from the kitchen, toilet, laundry, and other sources. It contains impurities such as suspended solid (sand, salt, clay), colloidal material (fecal matter, bacteria, plastic and cloth fiber), dissolved materials (nitrate, phosphate, calcium, sodium, ammonia), and disease-causing microbes. When organic wastes from the sewage enter the water bodies, it serves as a food source for micro-organisms such as algae and bacteria. As a result, the population of these micro-organisms in the water body increases. Here, they utilize most of the dissolved oxygen for their metabolism. This results in an increase in the levels of Biological oxygen demand (BOD) in river water and results in the death of aquatic organisms. Also, the nutrients in the water lead to the growth of planktonic algal, causing algal bloom. This causes deterioration of water quality and fish mortality.
Various steps have been taken to improve the quality of air in
(a) Introduction of CNG (Compressed Natural Gas):By the orderof the supreme court of
(b) Phasing out of old vehicles
(c) Use of unleaded petrol
(d) Use of low-sulphur petrol and diesel
(e) Use of catalytic converters
(f) Application of stringent pollution-level norms for vehicles
(g) Implementation of Bharat stage I, which is equivalent to euro II norms in vehicles of major Indian cities.
The introduction of CNG-powered vehicles has improved
(a) Greenhouse gases: - Thegreenhouse effect refers to an overall increase in the average temperature of the Earth due to the presence of greenhouse gases. Greenhouse gases mainly consist of carbon dioxide, methane, and water vapour. When solar radiations reach the Earth, some of these radiations are absorbed. These absorbed radiations are released back into the atmosphere. These radiations are trapped by the greenhouse gases present in the atmosphere.. This helps in keeping our planet warm and thus, helps in human survival. However, an increase in the amount of greenhouse gases can lead to an excessive increase in the Earth’s temperature, thereby causing global warming.
(b) Catalytic converter: - Catalytic converters are devices fitted in automobiles to reduce vehicular pollution. These devices contain expensive metals such as platinum, palladium, and rhodium that act as catalysts. As the vehicular discharge passes through the catalytic converter, the unburnt hydrocarbons present in it get converted into carbon dioxide and water. Carbon monoxide and nitric oxide released by catalytic converters are converted into carbon dioxide and nitrogen gas (respectively).
(c) Ultraviolet-B: - Ultraviolet-B is an electromagnetic radiation which has a shorter wavelength than visible light. It is a harmful radiation that comes from sunlight and penetrates through the ozone hole onto the Earth’s surface. It induces many health hazards in humans. UV −B damages DNA and activates the process of skin ageing. It also causes skin darkening and skin cancer. High levels of UV −B cause corneal cataract in human beings.
Wastes generated at home include plastic bags, paper napkin, toiletries, kitchen wastes (such as peelings of vegetables and fruits, tea leaves), domestic sewage, glass, etc.
Wastes generated at schools include waste paper, plastics, vegetable and fruit peels, food wrappings, sewage etc.
Wastes generated at trips or picnics include plastic, paper, vegetable and fruit peels, disposable cups, plates, spoons etc.
Yes, wastes can be easily reduced by the judicious use of the above materials. Wastage of paper can be minimized by writing on both sides of the paper and by using recycled paper. Plastic and glass waste can also be reduced by recycling and re-using. Also, substituting plastics bags with biodegradable jute bags can reduce wastes generated at home, school, or during trips. Domestic sewage can be reduced by optimizing the use of water while bathing, cooking, and other household activities.
Non- biodegradable wastes such as plastic, metal, broken glass, etc are difficult to decompose because micro-organisms do not have the ability to decompose them.
Global warming is defined as an increase in the average temperature of the Earth’s surface.
Causes of global warming: Global warming occurs as a result of the increased concentration of greenhouse gases in the atmosphere. Greenhouse gases include carbon dioxide, methane, and water vapour. These gases trap solar radiations released back by the Earth. This helps in keeping our planet warm and thus, helps in human survival. However, an increase in the amount of greenhouse gases can lead to an excessive increase in the Earth’s temperature, leading to global warming. Global warming is a result of industrialization, burning of fossil fuels, and deforestation.
Effects of global warming: Global warming is defined as an increase in the average temperature of the Earth’s surface. It has been observed that in the past three decades, the average temperature of the Earth has increased by 0.6ºC. As a result, the natural water cycle has been disturbed resulting in changes in the pattern of rainfall. It also changes the amount of rain water. Also, it results in the melting of Polar ice caps and mountain glaciers, which has caused a rise in the sea level, leading to the inundation of coastal regions.
Control measures for preventing global warming:
(i) Reducing the use of fossil fuels
(ii) Use of bio-fuels
(iii) Improving energy efficiency
(iv) Use of renewable source of energy such as CNG etc.
(v) Reforestation.
(vi) Recycling of materials
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Column A |
Column B |
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Catalytic converter |
(ii) |
Carbon monoxide and nitrogen oxides |
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Electrostatic precipitator |
(i) |
Particulate matter |
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Earmuffs |
(iii) |
High noise level |
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Landfills |
(iv) |
Solid wastes |
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(a) Eutrophication:- It is the natural ageing process of a lake caused due to nutrient enrichment. It is brought down by the runoff of nutrients such as animal wastes, fertilizers, and sewage from land which leads to an increased fertility of the lake. As a result, it causes a tremendous increase in the primary productivity of the ecosystem. This leads to an increased growth of algae, resulting into algal blooms. Later, the decomposition of these algae depletes the supply of oxygen, leading to the death of other aquatic animal life.
(b) Biological magnification: - To protect the crops from the several diseases and pests, a large number of pesticides are used. These pesticides reach the soil and are absorbed by plants with water and minerals from the soil. Due to rain, these chemicals can also enter water sources and into the body of aquatic plants and animals. As a result, chemicals enter the food chain. Since these chemicals cannot be decomposed, they keep on accumulating at each trophic level. The maximum concentration is accumulated at the top carnivore’s level. This increase in the concentration of pollutants or harmful chemicals with an increase in the trophic level is called biological magnification. For example, high DDT concentrations were found in a pond. The producers (phytoplankton) were found to have 0.04 ppm concentration of DDT. Since many types of phytoplankton were eaten by zooplankton (consumers), the concentration of DDT in the bodies of zooplankton was found to be 0.23 ppm. Small fish that feed on zooplankton accumulate more DDT in their body. Thus, large fish (top carnivore) that feed on several small fish have the highest concentration of DDT.
(c) Ground water depletion and ways for its replenishment: - The level of ground water has decreased in the recent years. The source of water supply is rapidly diminishing each year because of an increase in the population and water pollution. To meet the demand of water, water is withdrawn from water bodies such as ponds, rivers etc. As a result, the source of ground water is depleting. This is because the amount of groundwater being drawn for human use is more than the amount replaced by rainfall. Lack of vegetation cover also results in very small amounts of water seeping through the ground. An increase in water pollution is another factor that has reduced the availability of ground water.
Measures for replenishing ground water:-
(i) Preventing over-exploitation of ground water
(ii) Optimizing water use and reducing water demand
(iii) Rain water harvesting
(iv) Preventing deforestation and plantation of more trees
The ozone hole is more prominent over the region of
Chlorine is mainly released from chlorofluorocarbons (CFC’s) widely used as refrigerants. The CFC’s magnate from the troposphere to the stratosphere, where they release chlorine atoms by the action of UV rays on them. The release of Chlorine atoms causes the conversion of ozone into molecular oxygen. One atom of chlorine can destroy around 10,000 molecules of ozone and causes ozone depletion.
The formation of the ozone hole will result in an increased concentration of UV - B radiations on the Earth’s surface. UV −B damages DNA and activates the process of skin ageing. It also causes skin darkening and skin cancer. High levels of UV −B cause corneal cataract in human beings.
Women and communities have played a major role in environmental conservation movements.
(i) Case study of the bishnoi community: TheBishnoi community in Rajasthan strictly believes in the concept of living peacefully with nature. In 1731, the king of
(ii) Chipko movement: The Chipko movement was started in 1974 in the Garhwal region of the
The following initiatives can be taken to prevent environmental pollution:
Measures for preventing Air pollution:
(i) Planting more trees
(ii) Use of clean and renewable energy sources such as CNG and bio-fuels
(iii) Reducing the use of fossil fuels
(iv) Use of catalytic converters in automobiles
Measures for preventing water pollution:-
(i) Optimizing the use of water
(ii) Using kitchen waste water in gardening and other household purposes
Measures for controlling Noise pollution:-
(i) Avoid burning crackers on Diwali
(i)
Measures for decreasing solid waste generation:-
(i) Segregation of waste
(ii) Recycling and reuse of plastic and paper
(iii) Composting of biodegradable kitchen waste
(iv) Reducing the use of plastics
(a) Radioactive wastes: - Radioactive wastes are generated during the process of generating nuclear energy from radioactive materials. Nuclear waste is rich in radioactive materials that generate large quantities of ionizing radiations such as gamma rays. These rays cause mutation in organisms, which often results in skin cancer. At high dosage, these rays can be lethal.
Safe disposal of radioactive wastes is a big challenge. It is recommended that nuclear wastes should be stored after pre-treatment in suitable shielded containers, which should then be buried in rocks.
(b) Defunct ships and e-wastes: - Defunct ships are dead ships that are no longer in use. Such ships are broken down for scrap metal in countries such as
E-wastes or electronic wastes generally include electronic goods such as computers etc. Such wastes are rich in metals such as copper, iron, silicon, gold etc. These metals are highly toxic and pose serious health hazards. People of developing countries are involved in the recycling process of these metals and therefore, get exposed to toxic substances present in these wastes.
(c) Municipal solid wastes: - Municipal solid wastes are generated from schools, offices, homes, and stores. It is generally rich in glass, metal, paper waste, food, rubber, leather, and textiles. The open dumps of municipal wastes serve as a breeding ground for flies, mosquitoes, and other disease-causing microbes. Hence, it is necessary to dispose municipal solid waste properly to prevent the spreading of diseases. Sanitary landfills and incineration are the methods for the safe disposal of solid wastes.
Electronic waste is described as the discarded electrical or electronic devices; and the residue of the electronic applications after their usage. Electronic equipment waste like cooling and freezing appliances, televisions, phone batteries, remotes, lamps, tools, computers etc. and these are destined for reuse, resale, recycle or as well as disposal. If these wastes are buried in land then this cause soil pollution which reduces the soil fertility and when they burnt then they cause air pollution.
Electronic waste treatment most common methods are reuse or recycling of the waste. On the other way, try to fix the electronic item instead of throwing. Don’t burn them because they release harmful chemicals which affects the living beings. Recycling process of E- waste includes various steps:- Sorting, Dismantling, Large size reduction process, small size reduction process, Magnetic separation, non- metallic and metallic components separation and then last step is water separation.
Electronic waste affects every human being very badly as this waste contains harmful and toxic components like lead, mercury, cadmium, polybrominated etc. and these can lead to environmental pollution or it adversely affects the human health.
D.D.T is a pesticide or a chemical pollutant which affects the human health when it follows exposure of high doses. And it is also considered as a human carcinogen (is a substance which cause cancer). DDT in water adversely affects the use of water and leads to water pollution. When the large number of pesticides or mercury is added and the toxins concentration level increase at each trophic level in the food chain is known as biomagnification, which leads to the mortality of the fishes.
High concentration of DDT in birds affects calcium metabolism. Egg shells become thin and breaks down before their maturity.
i. True (figure A is solar plate which generates solar energy and the second one- figure B is wind mill which generates wind energy and they both are non- polluting).
ii. 1. it generates electrical energy.
2. Solar cookers are used to prepare food with the help of solar cooker.
iii. Photovoltaic cells are made up of semiconductor material. They trap the photons from the sunlight and convert them into the flow of electrons and this will produce an electric current. One solar panel consists of many photovoltaic cells which adds up to give a large amount of electric current for various purposes.
Increase in the concentration of toxic materials like cadmium, arsenic, lead, zinc, mercury etc. and some pesticides which are non- biodegradable; at each trophic level is known as Biomagnification.
Reforestation is the process of plantation in the forest or establishing a desired forest community on that area where the number of trees has been decreasing by natural calamity or some anthropogenic activities. Reforestation makes the land more fertile or usable to the wildlife and to improve life human beings by providing them food, shelter etc. Some reforestation techniques are given like direct seeding, natural regeneration, topsoil transposition etc.
Electronic waste affects every human being very badly as this waste contains harmful and toxic components like lead, mercury, cadmium, polybrominated etc. and these can lead to environmental pollution or it adversely affects the human health.
Electronic waste treatment most common methods are reuse or recycling of the waste. On the other way, try to fix the electronic item instead of throwing. Don’t burn them because they release harmful chemicals which affects the living beings. Recycling process of E- waste includes various steps:- Sorting, Dismantling, Large size reduction process, small size reduction process, Magnetic separation, non- metallic and metallic components separation and then last step is water separation.
Organic farming is a technique that involves the cultivation of flora and rearing of animals in the natural ways. It involves the use of biological materials, bio- fertilizers, avoiding synthetic substances or chemical fertilizers to maintain the soil fertility and ecological balance by reducing or minimizing the pollution and wastage. It uses ecologically balanced agriculture based processes like crop rotation method, green manure, pesticides free crops production etc.
Organic farming is very beneficial or eco- friendly as it uses few pesticides to control the diseases, reduces soil erosion etc. it helps in producing the nutritious food. As we all know that, many techniques have been used for this farming for the developing nation like India. Now a days chemical fertilizers, more use of pesticides and herbicides are used in the agriculture for the fast production of crops but when these chemicals leaches out from the soil, river, lakes etc. they pollutes the water which automatically leads to the mortality of aquatic organisms and damages the soil fertility.
Waterlogging is the saturation of soil with the water, i.e. known as soil may be waterlogged. When it is saturated with water, then the air phase is restricted and anaerobic condition is operated instead of using aerobic condition. And, soil salinity is defined as the salt content in the soil and the process of increasing salt is known as salinization. Both problems have come in the wake of the green revolution.
Causes:-
Adverse effects:-
Multipurpose trees or multifunctional trees are those which are grown for some purpose (deliberately or we can say intentionally) and gives more than one output or to serve various purposes. These type of trees give food in various forms like fruits, nuts, leaves which are edible as vegetables. They provides us habitat (some trees wood is used for making wooden house), shade, and fulfils the basic human needs. Some multipurpose trees with their botanical and local names; and their uses are as follows:-
Landfill site, also known as tip, dump, garbage dump or dumping ground which is a method of filling in and reclaiming excavated pits or the disposal of waste material by burying it in land. Basic characteristics of a modern landfill site are as follows:-
(Note*: Deonar dumping ground is the oldest and the largest which sets up in 1927, in Mumbai.)
Electrostatic precipitator is highly efficient filtration device which allows the flow of gases. This device can easily remove the fine particulate matter like dust and smoke from air stream that is present in industrial and thermal power exhausts using force of an induced electrostatic attraction like charges repel or unlike charges attract. Electrostatic precipitator have charged plates which are connected with the ground. The electrode wires are provided with high volts electric current. These small particles present in dirty air are firstly charged electrically and then allowed to settle down over differently charged scrubbers.
Working:- This device contains electrode wires which are maintained at high volts which releases electrons. These electrons then attach to dust particles that gives them net negative charge. The collecting plates are present on the ground level and they attract the dust particles.
Lead lapsy: caused due to contamination of Lead in water bodies.
Fluorosis; Knock- knee syndrome: caused due to contamination of fluorides in ground water.
Many other diseases caused by accumulation of any heavy metals occurred; like:
Methanoglobinaemia, Arsenocosis etc.
The concept of Joint Forest Management (JFM) has been introduced by the Government of India in 1980s. So, to work in the close association with the local communities for protecting and managing forests. And, this type of cooperation, the communities get benefits of various forest products (example: fruits, gum, rubber etc.) and thus the forest can be conserved in a sustainable (the ability to be maintained or the avoidance of natural resources in order to maintain the ecological balance) manner.
When the cornea of the human eye absorbs these UV- B radiations then it causes inflammation of cornea also called snow blindness. UV- B radiations are very harmful and cause ozone depletion in the stratosphere; these radiations ranges from 290-320 nm. When these radiations increase on the earth surface it also causes various diseases like skin cancer, herpes, snow blindness etc.
