Assignment Code: AHE-01/TMA/2022

Course Code: AHE-01

Assignment Name: Application Oriented Course on Human Environment

Year: 2022

Verification Status: Verified by Professor

Maximum Marks: 100

Q1. Differentiate between the following pairs: (10)

(i) Expansive and stationary population histograms

Ans)

(ii) Food chain and Food web

Ans)

Q2. Write short notes on the following: (20)

(i) Bhopal gas tragedy.

Ans) The Bhopal gas tragedy occurred in 1984, when a chemical leak occurred in the city of Bhopal, Madhya Pradesh, India. It was dubbed the worst industrial accident in history at the time. On December 3, 1984, approximately 45 tonnes of the hazardous chemical methyl isocyanate escaped from an insecticide plant controlled by Union Carbide Corporation's Indian affiliate. The gas spread quickly across the heavily populated areas surrounding the factory, killing hundreds of people, and causing panic as tens of thousands more rushed to evacuate Bhopal.

The death toll was believed to reach between 15,000 and 20,000 people in the end. A half-million survivors had lung issues, eye irritation or blindness, and other illnesses as a result of their exposure to the deadly gas, with many receiving only a few hundred dollars in compensation. Investigations later revealed that the disaster was caused by inadequate operating and safety procedures at the understaffed plant. The former manufacturing site was given to the state of Madhya Pradesh in 1998.

More than 400 tonnes of industrial trash were still present on the site in the early twenty-first century. Despite repeated complaints and legal attempts, neither the Dow Chemical Company, which purchased Union Carbide in 2001, nor the Indian government has cleaned up the site effectively. Chronic health problems and a high rate of birth malformations have been blamed on contamination of the soil and water in the area. Because of groundwater contamination, the Indian Supreme Court ordered the state to provide clean drinking water to Bhopal residents in 2004. A Bhopal court found several former executives of Union Carbide's India division, all of whom were Indian citizens, guilty of negligence in the catastrophe in 2010.

(ii) The three-cell air circulation model for each hemisphere of earth to explain global circulation of air.

Ans) The earth's surface is heated by solar radiation reaching it due to unequal heating of the earth's surface. We've also discovered that solar energy does not reach everyone in the same way. Due to absorption, scattering, and reflection of energy by the atmosphere, some places receive more solar radiation while others receive less. These effects become more effective and crucial when energy has to travel longer distances.

The temperature of the sea surface does not change rapidly, whereas terrestrial areas are rapidly heated or chilled. This is why, during the day, the air above the land heats up and expands, whilst the air above the sea remains relatively unchanged. As a result, the air above the land moves higher in altitude towards the ocean. At lower altitudes, there is a movement of air mass from the sea towards the land to compensate.

As a result, a type of circulation is formed. Air goes from sea to land in the lower section and from land to sea in the top part. This type of circulation is only found in coastal locations and is of a local nature. The unequal heating of different parts of the globe, on the other hand, plays a bigger role. On a global scale, this results in air circulation. As a result, to depict global air circulation, the three-cell air circulation model for each hemisphere of the planet was developed to explain global air circulation.

(iii) Effect of air pollution on animals.

Ans) Some effects of air pollution on animals 

1. A study in Mexico Metropolis compared dogs living in the city to dogs living in an unpolluted countryside, a city known for its high levels of air pollution. They discovered that dogs in polluted areas had inflamed brains and other disease-like symptoms.

2. However, there are still few research on the topic. Indoor pollution are also harmful to pets, with one study finding that cats' lung capacity decreased when they shared a house with a smoker.

3. Their respiratory systems were proven to be harmed by a mixture of particles, nitrous oxide, and sulphur dioxide.

4. Pollutants caused respiratory issues once again. Mice were kept outside in cages for four months in a study in Sao Paolo, Brazil. One cage contains filtered clean air, while the other contains dirty air that has not been filtered. The study discovered that when females are exposed to unfiltered air from an early age, their reproductive success decreases.

(iv) Land as a non-living resource.

Ans) The emergence and evolution of all living organisms, including humans, is dependent on land. Only 14,960 million hectares (M ha) or 29.22% of the earth's total surface area being land, with the remaining 36,100 M ha or 70.78 percent being seas. Steep mountains, arid deserts, marshy marshes, and other natural features make up less than 3Wo of the land surface, making it unsuitable for agriculture and productive activities.

Production of food grains and other commodities is compelled, and development activities have quickened, putting conflicting and rising demands on land. On the one hand, as the world's population grows, so does the demand for food. On the other hand, numerous development activities, such as housing, road construction, and dam construction, encroach on productive land. Over the previous five decades,

However, grasslands have decreased by 78.8%, fallows and cultivable wastelands have decreased by 20.3%, and non-cultivable barren land has decreased by 44.2 percent. Clearing forests has allowed for the growth of cropland. At the same time, as a result of urbanisation and industrialization, crop areas have been diverted to non-agricultural uses. Nonetheless, forest areas are expanding as a result of post-independence reorganisation of private forest land holdings and then through plantation programmes.

Changes in the amount of land accessible per inhabitant would have a tremendous impact on the environment. Other inputs such as water, fertilisers, and energy will be in increasing demand. Corrective and additional actions must be included to the land budget to prevent or mitigate potential disturbances in various aspects of the environment. This is especially important in light of ongoing land degradation and the pervasive problem of soil erosion across the country.

Q3. (a) Discuss the harmful effects of plant protection chemicals and their effect on animals and human health. (5)

Ans) The harmful effects of plant protection chemicals and their effect on animals and human health are:

Death of Non-target Organisms: Plant protection agents are designed to kill their respective target creatures, but they occasionally kill valuable insect species that, in addition to providing alternative food for birds, play a crucial role in pollination and dispersal of wild plants and forest trees. Fungicides used to protect crop plants against fungal infection eliminate a beneficial type of fungus that aid in the solubilization of phosphates, an essential plant nutrient. Herbicides kill not only the undesired weeds, but also the sensitive, beneficial side crops that protect the crops from other illnesses.

Target Organism Immunity: Another issue associated with excessive use of plant protection chemicals is that target organisms are gradually acquiring/immunity to these chemicals through the evolution of pesticide-resistant strains, implying that these chemicals are no longer effective against target organisms. Some bugs have evolved detoxification mechanisms to combat the chemicals used to kill them. Nearly 447 species, including major insects, mites, and other pests, had developed resilience to the chemicals used to combat them by 1984. Similarly, 48 weed species have developed pesticide resistance. As a result, significant swaths of agricultural land have become unsuitable for cultivation. Even biocides' initial benefits to agriculture have backfired in a number of cases. Immune forms of insect pests, for example, have displaced the original population, luring agriculturists to use even more virulent biocides on a more frequent basis.

Food Contamination: Now let's look at how these plant protection compounds contaminate food. Food grains, fruits, vegetables, and oilseeds are sprayed with biocides to prevent them from spoilage during storage. Because these chemicals are not biodegradable, they remain in the food chain for a long time. Humans consume the poisoned agriculture products directly or indirectly through milk, meat, eggs, fish goods, and water.

(b) Diagrammatically depict the sulphur cycle. (5)

Ans) Sulphur can be found in the atmosphere as hydrogen sulphide and sulphur dioxide, as well as in the soil as sulphates, sulphides, and organic sulphur. Volcanic emissions are the sole known natural source of the aforementioned gases in the atmosphere. Sulphur is required for the formation of some amino acids and B-complex vitamins. The cycle of sulphur in the biosphere is depicted in the diagram below. Sulphur is integrated into the proteins of autotroph tissues in the form of sulphates. It subsequently goes through the grazing food chain, where it is discharged in excess through animal faeces. Protein degradation releases sulphur within the detritus food chain.

Fungi like Aspergillus and Neurospora decompose proteins in aerobic conditions, while bacteria like Escherichia and Proteus decompose proteins under anaerobic conditions. Sulphate-reducing bacteria like Desulphoyibro desulfuricans produce hydrogen sulphide in anaerobic soils and sediments. Beggiatoa species convert hydrogen sulphide to elemental sulphur, while Thiobacillus species convert it to sulphate. Sulphur photosynthetic bacteria that oxidise hydrogen sulphide to elemental sulphur are also seen in green and purple colours.

Q4. (a) List any four effects of urbanization on the environment and describe any one of them. (2+2=4)

Ans) The four effects of urbanization on the environment are:

1. Land Use Modifications.

2. Water Resources Depletion.

3. Building Materials: A vast quantity of building materials is required for the construction of houses and other structures. Every year, the city of Delhi is anticipated to require 80.000 additional homes. These would require 1,100 million bricks each year, while Delhi's kilns can only produce 140 million per year. The remainder comes from nearby places with fertile ground, inflicting more damage to good agricultural land.

4. Industries.

(b) Describe the steps involved in the primary and secondary treatment of sewage water in order to make it suitable for drinking purposes. (6)

Ans) The steps involved in the primary and secondary treatment of sewage water in order to make it suitable for drinking purposes are:

Natural sedimentation occurs in reservoirs, and sewage or waste waters are stored in basins or settling tanks in treatment plants. If water is allowed to stand or flow quietly at low velocity, silt, clay, and other fine particulates settle to the bottom. Extremely fine particles or colloidal material will not be removed by simple sedimentation. This phase is mostly used as a warm-up for other treatment options.

Coagulation combines fine particles and colloidal elements into conglomerates. These are known as flocs (plural: flocs) and are large enough to settle in basins and catch on filter surfaces. Special chemicals called as coagulants/flocculants, such as potash alum, are used to cause coagulation. This process is also referred to as flocculation.

By running waste water over a bed of sand or finely graded coal, or a matrix of fibrous material supported in a perforated core, suspended solids, colloidal material, bacteria, and other creatures are filtered away. Filtration does not remove soluble elements like salts and metals in ionic form.

The water is disinfected once it has been filtered. Water can be treated in a number of ways to destroy live organisms, particularly pathogenic bacteria. Chlorine or its derivatives, such as bleaching powder, are frequently used for disinfection. Ultraviolet radiation, ozone, and silver ions are some of the less commonly used disinfection treatments. Boiling is the most common disinfection method used in the home.

The waste treatment stages leading up to this point are referred to as primary treatment, and sewage or waste water handled in this way can be properly disposed of after careful inspection for harmful wastes left behind in trace amounts. This water, however, is unfit for human consumption and must be softened and aerated before it can be safely consumed. Secondary treatment is what it's called.

Softening is a water treatment procedure that removes unwanted calcium and magnesium cations from hard water. The water is softened using two methods: it is treated with lime and soda ash to precipitate calcium and magnesium ions as carbonates, which is then filtered; or it is passed through porous cation exchangers and left cation free.

Aeration is the act of forcing air through water in the form of bubbles in order to supply oxygen while reducing carbon dioxide, hydrogen sulphide, and taste-producing gases or vapours.

Q5. (a) Differentiate between geological and accelerated erosion. (2)

Ans)

(b) Describe the two broad methods of processing and recycling industrial wastes. (6)

Ans) The two broad methods of processing and recycling industrial wastes are:

Waste Reuse: Waste material can sometimes be used as a raw material with minimal processing. Waste reuse or waste exchange refers to the transfer of waste "as is" to another facility without it being reprocessed. Unwanted commercial resources, such as old chemicals or untested products that do not match the purchasing industry's high-quality control criteria, can be reused without being processed. Process wastes like cardboard to make paper pulp, copper, or other metal salt solutions to recover metals, and oils to utilise as fuels. Other materials that can be used as industrial feedstocks are included in this category.

Waste Recycling: Recycling differs from reuse in that waste must first be processed before being employed in a manufacturing process. Recycling is the process of reprocessing waste for material recovery when it is not possible to transport waste "as is." Baghouse dust from scrap steel processors, for example, can be combined with waste sulphuric acid to generate galvaniser's pickle acid, which contains up to 25% zinc oxide. The used pickle fluid, which contains 8-10% zinc sulphate and some iron salts, can subsequently be used as fertiliser in agricultural fields. The best example of waste recycling is the use of waste organic solvents.

(c) Differentiate between carcinomas and lymphomas. (2)

Ans)

Q6. (a) Discuss the statement that “agricultural residues and agro-industrial wastes, in fact are no waste. All of them have some use or the other and in that sense they are resources whose conventional use needs to be upgraded and better usability fully harnessed.” (4)

Ans) As the demand for industrially produced goods grows, so does the strain on the availability of both non-renewable and renewable resources such as forests. As a result, agricultural residues and agro-industrial wastes are being used more frequently.

In the country, a major integrated paper mill producing newsprint from bagasse is already operational. More paper mills of this type are likely to be built in the future. Similarly, many enterprises that previously used coal have moved to rice husk as a fuel due to cost savings, despite the fact that rice husk storage requires a lot of space. The supply of paddy straw is also plentiful. Each year, Punjab generates roughly 5 million tonnes of paddy straw. It can readily meet the majority of the farm sector's electricity requirements.

As a result, it is clear that agricultural residues and agro-industrial wastes are not wastes at all. They're all useful in some way, and in that sense, they're a resource whose traditional use has to be updated and its full potential utility exploited. Their creation is relatively inexpensive but failing to put them to good use after they have been created is costly.

(b) Describe the role of Non-Governmental agencies in environmental protection and management in India and the problems faced by them. (4)

Ans) Environmental protection and management can be greatly aided by non-governmental organisations. These organisations are not subject to government control, and they are free to make their own decisions and engage in any activities they like. Non-governmental or volunteer organisations are distributed over the country, even in small communities, and as a result, they have no trouble reaching people in real life.

A considerable number of such organisations have been drawn to environmental protection. Voluntary organisations make a significant contribution, but they often encounter challenges. For starters, they frequently lack the necessary staff to carry out certain programmes. Another issue is that they do not have easy access to reliable data and information. They have no source of income, therefore most of their activities require them to gather funds on their own, putting them in a financial bind.

(c) Give the two aims of environmental conservation. (2)

Ans) The two aims of environmental conservation are:

1. To assure the preservation of a high-quality environment that takes into account aesthetics, recreation, and product requirements.

2. Establishing a balanced harvest and regeneration cycle to assure a constant output of beneficial plants, animals, and materials.

Q7. (a) Briefly discuss the concept of the new global economic system for long term survival of the human race. (4)

Ans) Maximum money flow, maximum output, maximum consumption, maximum resource utilisation, and maximum profit characterise the current economic system. This so-called frontier economy should be replaced by a spaceship economy, which states that the planet, like a spaceship, is a closed system.

Recycling, conservation, the utilisation of renewable resources, product durability, and a clean and healthy environment are all promoted by a spaceship economy or a sustainable economy. People exist within the confines of the earth's boundaries. Future growth patterns should be substantially less material-intensive. Rather of recycling, broken items should be mended. Hazardous and non-biodegradable wastes would be avoided to the greatest extent practicable.

Only with new policies and political directions can a sustainable economy be developed and succeeded. Education and awareness are important. The most basic change would have to be a shift in ethics pushed by parents, schools, and government organisations. The government can assist by enacting new laws that promote the development of a sustainable society. As a result, a mix of personal and governmental actions can contribute to the overall change to a sustainable society with a sustainable economy.

(b) Write about the Environment (Protection) Act of India, passed by the parliament on 23rd May 1986. (4)

Ans) Parliament passed the Environment (Protection) Act on May 23, 1986. The Act is based on Article 253 of the Constitution and relates to the Stockholm Conference in 1972. The Union Government has been given significant powers for the prevention, control, and abatement of environmental pollution as a result of this Act. The powers include coordinating state action, planning and implementing national programmes, establishing environmental quality standards, particularly those governing the emission or discharge of pollutants, and imposing limits on the location of industries, among others.

The stated powers are quite broad; they include handling hazardous substances, preventing environmental accidents, conducting research, inspecting polluting units, establishing laboratories, and disseminating information, among other things. The Act envisions a wide range of administrative procedures and organisations. If the Act is carried out in its entirety, it will turn the Ministry of Environment and Forests into a super ministry, in charge of all industrial and other developmental activities. A cautious approach to enforcing this Act could only result in environmental window-dressing of government-enacted legislation.

(c) Why is the following statement a misconception?

“Cities are polluted whereas villages are not.” (2)

Ans) The statement ‘Cities are polluted whereas villages are not’ is a misconception. In fact, burning cow dung and wood produces pollution-causing smoke. Although people tend to connect cities with pollution, crime, and worry, rural living can come with its own set of expenses. Disease-carrying insects and arachnids, for example, can detract from the health value of that otherwise gorgeous Maine home. In other circumstances, rural pollution is a serious problem. In India, air pollution was responsible for the deaths of 1.1 million people in 2015, with rural populations accounting for 75% of the victims rather than urban residents. This is due to the fact that people who live in rural areas are more likely to breathe air that has been contaminated by the burning of agricultural fields, wood, or cow dung (used for cooking fuel and heat).

Q8. (a) Discuss how organic farming can be used for improving land quality. (6)

Ans) Improving land quality involves using organic matter inputs such as green manures, compost, and farmyard manure, as well as cover crops, crop rotations, and intercropping, and using low soil disturbance tillage to maintain and produce a fertile living soil. Crops and animals are being integrated, overgrazing is being reduced, and nutrient recycling is being made easier on the farm. High amounts of organic matter and permanent soil cover, such as cover crops or mulch, improve water penetration and retention capacity, reducing the quantity of water needed for irrigation.

(b) Explain why India became the cradle of cultural exchange between East, West, Central Asia, and South East Asia? (4)

Ans) Because the severe geographical obstacles isolating the Indian subcontinent were located near the ancient and mediaeval world's major roadways, India became a focal point for cultural interchange. Those who mustered the bravery to transcend these obstacles in the past found themselves in a completely different world. In terms of culture, such brave artists, soldiers, merchants, and messengers found that they had enough to exchange. As a result, India became the cradle of East-West, Central-Asian, and Southeast-Asian cultural interchange.

Q9. Write short notes on the following: (10)

(i) Communicable diseases

Ans) A communicable disease is one that is spread from one person to another through a variety of ways that include: contact with blood and bodily fluids; breathing in an airborne virus; or by being bitten by an insect. Reporting of cases of communicable disease is important in the planning and evaluation of disease prevention and control programs, in the assurance of appropriate medical therapy, and in the detection of common-source outbreaks. California law mandates healthcare providers and laboratories to report over 80 diseases or conditions to their local health department. Some examples of the reportable communicable diseases include Hepatitis A, B & C, influenza, measles, and salmonella and other food borne illnesses.

These diseases spread depends on the specific disease or infectious agent. Some ways in which communicable diseases spread are by:

1. Touching an infected individual, sexual intercourse (gonorrhoea, HIV), faecal/oral transmission (hepatitis A), or droplets (influenza, TB)

2. Contact with a contaminated surface or object (Norwalk virus), contaminated food (salmonella, E. Coli), contaminated blood (HIV, hepatitis B), or polluted water (cholera)

3. Bites by disease-carrying insects or animals (mosquitoes: malaria and yellow fever; fleas: plague); and disease transmission through the air, such as tuberculosis or measles.

(ii) Solar energy

Ans) Biogas is a low-cost, high-efficiency fuel with a renewable source. Other renewable energy generation sources have lately been investigated. For example, systematic attempts are being made to harness solar energy to satisfy the needs of our rural poor. It is a decentralised energy system that may be used to suit a variety of Indian people's needs. Thermal conversion can take many forms, including solar cooking, water heating, water desalination, space heating, crop drying, and so on. Solar collectors for high-temperature applications are being developed at a low cost. In the country, there are around 380 solar water heating systems in use. Over 1,000 large-capacity water heating systems are now being installed.

Solar energy can also be used to generate electricity. Solar panels focus a lot of light energy into photovoltaic cells, which charge the batteries that provide electricity. Pumps, street lighting, and even refrigerators can be powered by this electricity. In rural regions, over 160 solar photovoltaic pumps have been constructed to provide water for consumption and irrigation. The Indian government has installed solar photovoltaic street lighting systems in over 150 villages as an experiment. Solar energy, which is installed in rural communities known as Urjagrams that are far from power lines, provides electricity to individuals who would otherwise not be able to dream of thermal or hydel electrical energy.