Any material that is discarded after it has served its purpose and is no longer useful is called ............... .
- compost
- waste
- manure
- pathogen
Answer
waste
Reason — Waste is any material that is discarded after it has served its purpose and is no longer useful. Compost and manure are useful products, while pathogens are disease-causing microorganisms.
Assertion (A): The use and throw concept is a significant cause of waste accumulation.
Reason (R): With development in technology today waste generation is increasing.
- Both A and R are true and R is the correct explanation of A.
- Both A and R are true but R does not explain A.
- A is true but R is false.
- A is false but R is true.
Answer
Both A and R are true but R does not explain A.
Explanation — The use-and-throw concept directly increases waste accumulation by encouraging the disposal of products after a single or short use. Although technological development has increased waste generation, it is not the direct explanation for the use-and-throw concept causing waste accumulation.
Waste generated as a result of demolition or construction of buildings is called ............... .
- industrial waste
- domestic waste
- construction waste
- mining waste
Answer
construction waste
Reason — Waste produced during the construction, renovation, or demolition of buildings and other structures is called construction waste. It includes materials such as bricks, concrete, wood, and metal.
Assertion (A): Agricultural wastes cause environmental problems.
Reason (R): They become breeding ground for pathogens.
- Both A and R are true and R is the correct explanation of A.
- Both A and R are true but R does not explain A.
- A is true but R is false.
- A is false but R is true.
Answer
Both A and R are true and R is the correct explanation of A.
Explanation — Agricultural wastes, when left unmanaged, can become breeding grounds for pathogens, leading to environmental pollution and health hazards. Therefore, the reason correctly explains why agricultural wastes cause environmental problems.
Which of the following is NOT a toxic substance present in e-waste?
- Cadmium
- Lead
- Mercury
- Steel
Answer
Steel
Reason — Cadmium, lead, and mercury are toxic substances commonly found in e-waste and can harm human health and the environment. Steel is not a toxic substance.
Assertion (A): E-waste is one of the fastest growing waste.
Reason (R): With advancement in Information Technology there is an increase in volume of obsolete electronic products.
- Both A and R are true and R is the correct explanation of A.
- Both A and R are true but R does not explain A.
- A is true but R is false.
- A is false but R is true.
Answer
Both A and R are true and R is the correct explanation of A.
Explanation — E-waste is one of the fastest-growing types of waste because rapid advances in Information Technology lead to frequent replacement of electronic devices, increasing the volume of obsolete electronic products.
The process of depletion of oxygen from water bodies occurring either naturally or due to human activities is called ................ .
- Biomagnification
- Oxygenation
- Eutrophication
- Acid rain
Answer
Eutrophication
Reason — Eutrophication is the process of depletion of oxygen from water bodies occurring either naturally or due to human activities. Biomagnification and acid rain are unrelated phenomena.
Wastes that pose a serious threat to human and environmental health are called
- Industrial waste
- Chemical waste
- Toxic waste
- Commercial waste
Answer
Toxic waste
Reason — Wastes are classified as toxic wastes because they pose a serious threat to human health and the environment. They result from industrial processes and products.
Assertion (A): Large scale epidemics, increased healthcare access, home based healthcare have contributed to a rise in biomedical waste.
Reason (R): Biomedical wastes require sophisticated processing plants, incineration and disassembly centres for proper disposal.
- Both A and R are true and R is the correct explanation of A.
- Both A and R are true but R does not explain A.
- A is true but R is false.
- A is false but R is true.
Answer
Both A and R are true but R does not explain A.
Explanation — Large-scale epidemics, improved healthcare access, and home-based healthcare increase the amount of biomedical waste. Although biomedical waste requires specialized processing and disposal facilities, this does not explain why its quantity has increased.
Agricultural waste being organic in nature undergoes ............... and creates conditions favourable for the growth of pathogens.
- fermentation
- nitrification
- magnification
- oxygenation
Answer
fermentation
Reason — Agricultural waste is organic in nature and undergoes fermentation, creating conditions favourable for the growth of pathogens. Nitrification, magnification, and oxygenation are not the processes responsible for this.
What is the increase in the concentration of various toxic substances along the food chain called?
- Eutrophication
- Bio-accumulation
- Biomagnification
- Demagnification
Answer
Biomagnification
Reason — Biomagnification refers to the increase in the concentration of various toxic substances along the food chain. Bio-accumulation, in contrast, is the concentrated toxic deposition at the higher trophic level.
Name the phenomenon of concentrated toxic deposition at the higher trophic level.
- Bio-accumulation
- Biomagnification
- Eutrophication
- Biodegradation
Answer
Bio-accumulation
Reason — The phenomenon of concentrated toxic deposition at the higher trophic level is known as bio-accumulation, as the toxic constituent gets increased while moving up the food chain from one trophic level to the next.
The accumulation of toxins will be higher in which of the following ?
- Water
- Algae
- Small fish
- Big fish
Answer
Big fish
Reason — Toxic substances become more concentrated at each successive trophic level through biomagnification. Therefore, big fish, being at a higher trophic level, accumulate the highest concentration of toxins.
The warming up of the atmosphere due to the increased concentration of GHG is known as ............... .
- Global Warming
- Climate change
- Acid rain
- Radiation
Answer
Global Warming
Reason — Global warming is the rise in the Earth's atmospheric temperature caused by the increased concentration of greenhouse gases (GHGs), which trap heat by preventing infrared radiation from escaping into space.
Assertion (A): Climate change is a result of increased GHG emissions.
Reason (R): Use of fossil fuels, population growth and reduced green cover result in GHG emissions.
- Both A and R are true and R is the correct explanation of A.
- Both A and R are true but R does not explain A.
- A is true but R is false.
- A is false but R is true.
Answer
Both A and R are true and R is the correct explanation of A.
Explanation — The use of fossil fuels, population growth, and reduced green cover increases greenhouse gas (GHG) emissions, which lead to climate change. Hence, the reason correctly explains the assertion.
In 2023 China was the largest contributor of Global greenhouse gas (GHG) emissions equal to the combined emissions of the US, India, European Union and Russia together. These five economies accounted for 60% of GHG emissions. What can be inferred.
- India's GHG emission are lower than China's.
- The Indian government's initiatives towards sustainability are effective.
- India is one of the major polluters in the world.
- All of the above.
Answer
India's GHG emission are lower than China's.
Reason — Since China's GHG emissions alone equal the combined emissions of the US, India, the European Union, and Russia, it can be inferred that India's emissions are lower than China's. The data does not provide enough information to support the other statements.
What is waste? Name two sources of waste.
Answer
The term 'waste' refers to any material that is discarded because it has served its purpose and is no longer useful.
Two sources of waste are-
- Domestic waste like food leftovers, bits of paper etc.
- Industrial waste like paints, sand, fly ash etc.
How is the 'use and throw' concept responsible for the increase in waste generation?
Answer
The 'use and throw' concept means to use any product only once and then dispose it.
For example, suppose we purchase a pen. After the ink is finished, we throw it away and buy a new pen instead of buying a refill and reusing the pen. If this example is followed by many people, the amount of waste will definitely increase in volume.
Thus, the 'use and throw' concept is responsible for the increase in waste generation.
What is acid rain? State its impact on the environment.
Answer
Acid rain is rainwater containing excessive amounts of acids.
Burning of coal, wood, and petroleum releases sulphur dioxide and nitrogen dioxide into the atmosphere. These gases dissolve in rainwater to form sulphuric acid, sulphurous acid, nitric acid, and nitrous acid. When these acids fall with rain or snow, it is called acid rain.
Impacts of acid rain on the environment:
- It increases the acidity of the soil and damages forests and crops.
- It corrodes buildings, monuments, statues, bridges, fences, and railings.
- It contaminates air and water, posing a threat to human health.
- It harms aquatic life.
- It affects plant growth by burning and drying the leaves.
What is meant by Ozone layer depletion? How is it harmful?
Answer
Ozone layer depletion is the thinning of the ozone layer present in the upper atmosphere. It occurs when chlorine and bromine atoms react with ozone and destroy its molecules.
It is harmful because the ozone layer absorbs the ultraviolet (UV) rays of the sun. When the ozone layer is depleted, more UV rays reach the Earth's surface.
Harmful effects of ozone layer depletion:
- It causes diseases such as skin cancer and cataract.
- It can cause genetic disorders, affecting heredity.
- It disturbs the ecological balance of marine ecosystems.
- It damages the physical and chemical properties of complex chemical substances.
What is E-waste? Why is it difficult to manage?
Answer
E-waste (electronic waste) refers to discarded electrical and electronic devices that are no longer useful due to redundancy, replacement, or damage.
E-waste is difficult to manage because:
- Rapid advances in Information Technology have increased the volume of obsolete electronic products.
- It contains hazardous substances such as lead, mercury, and cadmium, which can harm human health and the environment.
- It requires specialised recycling and disposal processes, making its management difficult.
Explain briefly how does the industrial waste reach the human beings and affect their health.
Answer
Industries such as chemical, pulp and paper, and food processing release wastes containing dust, carbon, metals, liquids, and radioactive materials, which pollute the air.
Burning coal and heavy oil releases sulphur dioxide, which combines with oxygen and water to form sulphuric acid, causing acid rain and health hazards. Smog (smoke + fog) causes asthma, bronchitis, shortness of breath, eye and nose irritation, and reduces visibility.
Industrial wastes containing heavy metals like cadmium, lead, mercury, copper, and chromium enter water bodies through direct discharge or leaching from waste dumps. This makes water poisonous and unhygienic, causing diseases in humans and animals if consumed without treatment.
Give a reason for each of the following:
(i) Poor waste management causes soil depletion.
(ii) Covid-19 pandemic increased waste production.
(iii) E-waste is rapidly increasing.
Answer
(i) Poor waste management leads to soil depletion because improper disposal of waste, especially in open dumps, leads to soil contamination with harmful chemicals and pollutants, reducing its fertility and overall health.
(ii) COVID-19 pandemic increased waste production because of the extensive use of single-use protective gear like masks, gloves, PPE kits, and sanitization products, which were often disposed of improperly. These items, mostly made of plastic, significantly contributed to biomedical and plastic waste during the pandemic.
(iii) With advancement in Information Technology, new electronic goods are being produced at a fast rate and this results in an increase in volume of obsolete electronic products. This is why e-waste is rapidly increasing.
Give two differences between toxic and non-toxic waste.
Answer
| Toxic waste | Non-toxic waste |
|---|---|
| Toxic waste is non-biodegradable. | Non-toxic waste is biodegradable. |
| It poses a serious threat to human health and the environment. | It does not pose a serious threat to human health and the environment. |
| For example, lead, cadmium, mercury etc. | For example, food leftover, fruit and vegetable peelings, bits of paper etc. |
Explain how eutrophication affects aquatic life.
Answer
Eutrophication is the depletion of oxygen from water bodies occurring naturally or due to human activities.
When nutrients increase due to waste accumulation, the growth of algae and phytoplankton increases. They reduce the penetration of oxygen, light, and heat into the water. As a result, aquatic plants cannot carry out photosynthesis, reducing the oxygen content of water and causing the death of most aquatic organisms.
What harm is done by dumping of waste near water bodies?
Answer
Waste dumped near water bodies percolates through the soil and contaminates the water. This leads to the accumulation of toxic substances in the water and the food chain through plants and animals. If consumed without treatment, the contaminated water can cause water-borne diseases such as typhoid and cholera.
Give a reason for each of the following:
(i) Marine animals and turtles are found dead in many coastal areas.
(ii) Radioactive waste is more harmful than any other waste.
(iii) Uncontrolled burning of waste causes air pollution.
Answer
(i) Marine animals and turtles die because they ingest plastic debris present in the ocean. Plastic blocks their digestive tract, leading to death. Marine turtles are more susceptible because their downward-facing spines prevent regurgitation.
(ii) Radioactive waste is more harmful than other waste because radioactive wastes cause pollution and damage the environment and the high level products of nuclear wastes remain in the environment for several hundred years.
(iii) Uncontrolled burning of waste creates smoke and other air pollutants that release toxic substances into the environment and cause air pollution.
What is biomagnification? What can be its effects on humans?
Answer
Biomagnification is the increase in the concentration of various toxic substances along the food chain.
Toxic substances at the level of primary producers get concentrated at each trophic level as they move up the food chain. Thus, the concentration of toxic substances is highest at the higher trophic levels.
For example, if there are traces of toxic chemicals in water, their concentration becomes much higher in algae. When fish eat the algae, the concentration of toxins increases further. When such fish are consumed by humans, these toxins enter the human body and can cause various kinds of diseases.
Name two diseases which occur because of waste accumulation on land.
Answer
Two diseases which occur because of waste accumulation on land are-
- Malaria
- Dengue
Name two common diseases caused as a result of gaseous pollution.
Answer
Two common diseases caused as a result of gaseous pollution are-
- Bronchitis
- Lung cancer
Name three water-borne diseases.
Answer
Three water-borne diseases are-
- Diarrhoea
- Cholera
- Typhoid
Explain briefly the need for management of waste.
Answer
Waste remains in the environment because we only move it from one place to another and do not get rid of it completely. Due to the rapid increase in human population, the environment is threatened by the large amount of waste produced.
Waste causes air pollution, soil degradation, and contamination of water bodies such as rivers and lakes. There is a close connection between waste, pollution, and environmental damage. The accumulation of waste threatens the survival of ecosystems, creating the need for proper waste management.
Currently, Mumbai generates close to 6,300 metric tonnes (MT) of waste, out of which more than 60% of daily solid waste, is sent to Kanjurmarg landfill which gets scientifically processed. The remaining waste is sent to Deonar dumping ground which remains untreated. What can Mumbai do to reduce its waste?
Answer
Mumbai can reduce its waste by:
- Segregating waste at source into biodegradable and non-biodegradable waste.
- Following the 3Rs – Reduce, Reuse and Recycle to minimise waste generation.
- Composting biodegradable waste and using it to prepare manure or biogas.
- Recycling materials such as paper, plastic, glass, and metals.
- Creating public awareness about proper waste management and avoiding the 'use and throw' concept.
- Ensuring scientific processing and proper disposal of waste instead of dumping it untreated in landfills.
Name the gas produced by the decomposition of accumulated waste. Why is this gas harmful?
Answer
Methane gas is gas produced by the decomposition of accumulated waste.
This gas is highly inflammable, and can cause an explosion if not managed properly.
Give a reason for each of the following:
(i) 'Use and throw' concept generates more waste.
(ii) Run off from fields leads to death in adjacent water bodies.
(iii) Birds feeding on agricultural waste are at the brink of extinction.
Answer
(i) The 'use and throw' concept encourages people to use a product once and discard it instead of reusing or recycling it, thereby increasing the volume of waste.
(ii) Run-off from fields carries fertilisers and pesticides into nearby water bodies. This causes eutrophication, reduces the dissolved oxygen content of water, and leads to the death of aquatic organisms.
(iii) Birds feeding on agricultural waste are at the brink of extinction because feeding on agricultural waste affects them adversely. Such birds have thinner and weaker egg shells and increased mortality.
What is Global Warming? Name any two Greenhouse Gases?
Answer
The rise in average mean temperature of the earth on account of enhanced concentration of greenhouse gases in the atmosphere is known as global warming.
Two Greenhouse gases are-
- Carbon dioxide
- Methane
Delhi has a massive municipal solid waste management problem with the massive landfills at Ghazipur, Okhla and Bhalswa at the centre of the issue. Delhi generates 11,332 tonnes of solid waste every day according to the latest estimate by the Municipal Corporation of Delhi (MCD), even as the civic body said that 4,360 tonnes of this garbage ends up at the city's three landfill sites.
(Source: 22nd February 2023, Hindustan Times)
(a) What is the cause for the issue mentioned above?
(b) Mention the three different methods of treating waste of the given type?
(c) How can an individual reduce waste generation?
(d) How can Delhi manage its waste following the example of Indore?
Answer
(a) The cause for the massive municipal solid waste management problem in Delhi is excessive generation of solid waste combined with inadequate waste processing and disposal systems.
(b) Three different methods of treating municipal solid waste like the type generated in Delhi are:
- Composting: Organic waste such as food scraps and garden waste can be biologically decomposed to form compost, which can be used as a natural fertilizer.
- Incineration: This involves burning waste at high temperatures to reduce its volume and sometimes generate electricity. However, it must be done in a controlled environment to avoid air pollution.
- Recycling and Resource Recovery: Waste materials like plastic, paper, glass, and metals can be sorted and processed to be reused in manufacturing new products, reducing the need for raw materials and saving energy.
(c) An individual can reduce waste generation in the following ways:
- Use reusable items like cloth bags, metal bottles, and containers instead of single-use plastics.
- Avoid the use-and-throw habit by repairing and reusing items instead of discarding them quickly.
- Segregate waste at home into dry, wet, and hazardous categories to help in proper recycling and disposal.
- Compost kitchen waste like fruit peels and vegetable scraps at home.
- Buy only what is needed to avoid wastage of food and other goods.
(d) Delhi can manage its waste more effectively by learning from Indore, which has been ranked as India’s cleanest city for several years. Here’s how Delhi can follow Indore’s example:
- Door-to-door waste collection: Like Indore, Delhi can ensure that waste is collected daily from each household and shop to prevent roadside dumping.
- Waste segregation at source: Indore citizens separate dry and wet waste before disposal. Delhi can promote awareness and strict rules to do the same.
- Use of composting and recycling plants: Indore processes almost all of its waste. Delhi can increase its number of compost and recycling centers to reduce landfill use.
- Strict monitoring and fines: Indore uses CCTV and teams to check for violations. Delhi can adopt similar systems to encourage discipline.
- Public participation: Indore succeeded due to citizen involvement. Delhi can launch awareness drives and school programs to promote cleanliness as everyone’s responsibility.
| City | Population (in million) | Total waste generated per day ('000 tonnes) | Waste generation (kg per capita per day) |
|---|---|---|---|
| Kolkata | 6.3 | 2.3 | 0.36 |
| Ahmedabad | 7.7 | 4.2 | 0.54 |
| Hyderabad | 8.4 | 3.7 | 0.44 |
| Chennai | 8.6 | 4.5 | 0.52 |
| Bangalore | 14.1 | 3.7 | 0.26 |
| Delhi | 16.3 | 5.8 | 0.41 |
| Mumbai | 18.4 | 6.5 | 0.35 |
Source: Census 2011, CNCB report.
(a) The chart given above gives details of waste generation in big cities. According to a study conducted by IIT Kanpur, 15% of this waste can be collected by rag pickers. Write a note on the importance of rag pickers in reducing wastes.
(b) How can schools and educational institutions aid in reduction of waste?
(c) What can be the cause of lower per capita waste generation in
(i) Bengaluru
(ii) Mumbai
(d) As a student of geography explain why the per capita generation of waste in Ahmedabad and Chennai is high.
Answer
(a) Rag pickers play a very important role in managing the waste generated in big cities like Delhi, Mumbai, and Kolkata. They are an important part of the waste management system in cities because they help in:
- Reducing the amount of waste going to landfills by collecting recyclable materials like plastic, glass, and metal.
- Saving energy and resources, as the materials they collect can be reused or recycled.
- Supporting the environment by reducing pollution and helping in proper waste segregation.
(b) Schools and educational institutions can aid in reduction of waste through following ways:
- Spreading Awareness about waste segregation, recycling, and the harmful effects of plastic.
- Set up separate bins for dry and wet waste in school premises to teach proper waste segregation.
- Encourage digital homework, double-sided printing, and reusing notebooks to minimize paper use.
- Start eco-clubs where students take up green projects like making compost pits, collecting e-waste, or organizing clean-up drives.
- Ban single-use plastics in canteens and during school events; promote cloth bags, steel bottles, and tiffins.
(c)
(i) Lower per capita waste generation in Bengaluru could be due to several possible reasons:
- Higher Public Awareness
- Better Waste Management Policies
- Tech-Savvy Population
- Composting and Recycling practice in households
- Greater Use of Reusables
(ii) Lower per capita waste generation in Mumbai could be due to the following reasons:
- High Population Density
- Limited Living Space
- Informal Recycling Sector (Rag pickers and waste workers)
- Economic Constraints
- Strict Civic Monitoring
(d) The high per capita waste generation in Ahmedabad and Chennai can be explained by the following reasons:
Higher Consumption Patterns: Both cities have growing urban middle-class populations with higher purchasing power, leading to more consumption and consequently more waste.
Urban Lifestyle: The use-and-throw culture is more prevalent in urban areas which generates more non-biodegradable waste.
Economic Growth: With industrialization and better living standards, more waste is generated through commercial and domestic activities.
Lack of Awareness and Segregation: In many parts of these cities, awareness about waste segregation is still developing, and mixed waste disposal contributes to higher measurable waste volumes.
Rag pickers and waste workers may not be very active.
Coral reefs are especially vulnerable to thermal pollution. In warm water, corals expel the algae living inside them and lose their colour, turning completely white. This is called coral bleaching. Corals can survive a bleaching event, but the more often it happens, the weaker they grow.
(a) What is thermal pollution?
(b) How does cold water cause thermal pollution?
(c) Thermal pollution may have natural causes. List the natural causes for thermal pollution. But in some cases thermal pollution due to natural causes results from human activities. Explain.
(d) What measures can be taken to reduce thermal pollution?
Answer
(a) Thermal pollution is the rise in the temperature of natural water bodies caused mainly by human activities. Most industries generate heat, use water as a coolant and dump the warm water into water bodies, thereby raising their temperature and causing thermal pollution.
(b) Thermal pollution is usually associated with heating of water, but it can also be caused by cold water. Climate change causes glaciers to melt faster, releasing large amounts of cold water into water bodies. This lowering of water temperature is known as cold-water thermal pollution.
(c) The natural causes of thermal pollution include heat from lightning strikes, wildfires, volcanoes and underwater thermal vents, all of which can cause sudden spikes in water temperature.
However, in some cases these natural causes also have a human element. For example, wildfires today are more frequent and more severe due to human-caused climate change and mismanagement of forests. Similarly, climate change leads to cold-water thermal pollution because it causes glaciers to melt faster. Thus, human activities intensify these otherwise natural causes.
(d) The following measures can be taken to reduce thermal pollution:
- Switching to clean energy sources like solar and wind for power generation.
- Changing the once-through cooling systems by (i) cooling the water before dumping it using cooling systems, or (ii) stopping the dumping of effluents in water bodies.
- Recycling the water.
According to a World Bank Report, global waste will increase by 70 per cent by 2050 unless urgent action is taken. Suggest five measures to reduce accumulation of waste.
Answer
Five measures to reduce accumulation of waste are:
- Implement comprehensive waste reduction and recycling programs to encourage waste separation and divert waste from landfills.
- Adopt extended producer responsibility (EPR) policies to hold manufacturers accountable for product lifecycle and promote sustainable design and disposal practices.
- Transition to a circular economy model that emphasizes reusing, repurposing, and refurbishing products, reducing waste generation.
- Conduct education and awareness campaigns to inform the public about responsible consumption, waste segregation and recycling techniques.
- Promote composting and organic waste management to divert organic waste from landfills and produce nutrient-rich compost for agricultural purposes.
These measures can help reduce waste accumulation, conserve resources and mitigate the environmental impact of waste generation.
Waste accumulation is the most visible form of pollution, which creates global environmental challenges. State any three such challenges and their probable remedies.
Answer
Three global environmental challenges and their probable remedies are as follows:
Land and soil pollution —
Both open dumps and landfills may contain toxins that seep into the soil and cause soil pollution. Scavengers and stray animals invade the open garbage dumps and spread the waste over a large area, thereby, spreading germs and diseases as well as destroying the beauty of the place.
Remedy —
- Implement strict waste management practices, including proper landfill design, lining, and leachate collection systems.
- Promote waste reduction, recycling, and composting to minimize the amount of waste sent to landfills.
Air pollution —
Improper waste incineration and open burning release harmful pollutants into the air, contributing to air pollution and respiratory health issues. As accumulated waste decomposes, it produces a large quantity of methane gas. This is highly inflammable, and can cause an explosion if not managed properly.
Remedy —
- Promote waste-to-energy technologies that use proper incineration methods and emissions control systems.
- Encourage the adoption of cleaner energy sources and waste management strategies that prioritize recycling and composting over incineration.
Water pollution —
Water pollution occurs when people discharge large amount of waste into water bodies, and the natural cleansing process in the water bodies cannot function properly. The process of eutrophication takes place due to introduction of nutrients and chemicals through discharge of domestic sewage, industrial effluents and fertilizers from agricultural fields. This causes death of most of the aquatic organisms, draining water of all its oxygen.
Remedy —
- Implement effective waste management systems, including proper waste collection, recycling, and awareness campaigns to discourage littering.
- Encourage the use of reusable and sustainable materials to reduce plastic waste.