UPSC 2019 Environment and Ecology Questions with Answers

Explanation

In India, pesticides must be registered with the Ministry of Agriculture & Farmers Welfare’s Directorate of Plant Protection, Quarantine & Storage before they can be used. A 2015 report by the Anupam Verma Committee recommended banning 27 pesticides, including some commonly used chemicals mentioned above:

Carcinogenic: Oxyfluorfen, Pendimethalin (causes Thyroid follicular cell adenoma) Endocrine disruptor: Dicofol, Carbofuran, Oxyfluorfen Eco-toxic: Carbofuran, Monocrotophos, Carbofuran, Oxyfluorfen.

Explanation

Waste-to-Energy (WTE) technologies consist of any waste treatment process that creates energy in the form of electricity or heat from several types of waste: from the semi-sol-id (e.g. thickened sludge from effluent treatment plants) to liquid (e.g. domestic sewage) waste. Landfill gas recovery, Gasification, Pyrolisis, Thermal Depolymerisation are examples of Waste-to-Energy (WTE) technologies.

Option (d) is correct: Pyrolysis is a process of chemical de-composition of organic matter brought about by heat. In this process, the organic material is heated in the absence of air until the molecules thermally break down to become a gas comprising smaller molecules (known collectively as syngas). Gasification can also take place as a result of partial combustion of organic matter in the presence of a restricted quantity of oxygen or air. The gas, so produced, is known as producer gas. The gases produced by pyrolysis mainly comprise carbon monoxide (25%), hydrogen and hydrocarbons (15%), and carbon dioxide and nitrogen (60%). It is used commercially as a waste to energy system that converts municipal solid waste into synthesis gas (syngas) containing hydrogen and carbon monoxide that can be used to generate power.

Explanation

Microbeads are manufactured solid plastic particles of less than one millimetre in their largest dimension. They are most frequently made of polyethene but can be of other petrochemical plastics such as polypropylene and polystyrene. They are used in exfoliating personal care products, toothpaste and in biomedical and health-science research.

Option (a) is correct: Microbeads can cause plastic particle water pollution and pose an environmental hazard for aquatic animals in freshwater and ocean water. NGT had earlier directed the GoI to test cosmetic products containing microbeads after a plea sought a ban on their use on the ground they are extremely dangerous for aquatic life and the environment.

Explanation

Methane hydrate is an ice-like substance formed when CH₄ and water combine at low temperature (up to 250C) and moderate pressure (greater than 3-5 MPa, which corresponds to combined water and sediment depths of 300 to 500 m).

Statement 1 is correct: Owing to the melting of ice, global warming might trigger the release of methane gas from these deposits hence having a significant impact on climate change.

Statement 2 is correct: Sediment and sedimentary rock units below Arctic permafrost have the temperature and pressure conditions suitable for the formation and stability of methane hydrate.

Statement 3 is correct: Methane is relatively short-lived in the atmosphere; a molecule of methane is oxidised to water and carbon dioxide within a decade or so, mainly by reaction with other trace gases.

Explanation

Burning stubble (parali) is the process of removing crop residue from the field in order to prepare it for the next crop. Open stubble burning releases a lot of harmful pollutants into the air, including smoke, particles, greenhouse gases (CO₂, N₂O, O₃ CH₄), air pollutants (CO, NH₃, NOx, SO₂, NMHC), and volatile organic compounds. These pollutants are dangerous to human health. Husk burning reduces the fertility of the soil by destroying its nutrients. When stubble burns, heat is produced that permeates the soil, causing the loss of moisture and beneficial microbes.

Explanation

There is a renewed interest in two dominant methods of geoengineering such as stratospheric sulphate aerosol increase and cirrus cloud thinning aims to reduce global warming effects. Geoengineering, often known as climate intervention, is the deliberate and extensive modification of the Earth’s climatic system with the intention of reducing global warming. The stratosphere can be injected with sulphate aerosol particles to block some of the sun’s rays and possibly cool the planet. Sulphur droplets are good at scattering the sun’s light back out into space and it does not heat the stratosphere as much as other aerosols.

Explanation

As per the Indian Nitrogen Assessment report, 2017, the share of agriculture in total GHG emissions has gradually declined from 28% in 1994 to 14% in 2016. Agricultural emissions in India are primarily from the livestock sector (54.6%) and the use of nitrogenous fertilizers (19%). Rice cultivation in anaerobic conditions accounts for a major portion of agricultural emissions (17.5%).

Statement 1 is correct: Agricultural soils release nitrogen oxides into the environment Fertilizers (especially nitrogen-based like urea) lead to the emission of nitrous oxide (N₂O), a greenhouse gas. Microbial processes such as nitrification and denitrification release NO, NO, and NO.

Statement 2 is correct: Cattle release ammonia into the environment Cattle excrete urea in urine, which breaks down into ammonia (NH₃) through microbial action. Livestock farming is a major contributor to ammonia emissions.

Statement 3 is correct: Poultry industry releases reactive nitrogen compounds into the environment Poultry litter (manure, bedding material, and feed waste) contains nitrogen compounds that can convert into ammonia, nitrates, and nitrites. This contributes to air and water pollution.

Explanation

Hydrogen-enriched CNG (H-CNG) is a blended gas. It is produced by mixing hydrogen with CNG. HCNG reduces emissions of CO up to 70% and engines can be calibrated to release lower amounts of NO. enables up to 5 % savings in fuel. It can be the first step towards the future Hydrogen economy. It gives better performance due to higher Octane rating of H2.

Statement 1 is incorrect: HCNG doesn’t eliminate but reduces emissions of CO up to 70%.

Statement 2 is correct: It can be used in place of gasoline, diesel fuel and propane (C3H8) / LPG and its combustion produces fewer undesirable gases.

Statement 3 is correct: The blending of hydrogen with CNG provides a blended gas termed as HCNG. Also, the ideal Hydrogen concentration is close to 20 %. It can prove to be the ideal fuel for heavy-duty vehicles and applications with high loads.

Statement 4 is incorrect: The current cost of Hydrogen is more than the cost of Natural Gas. So, HCNG’s cost is more than CNG.

Explanation

Statement 1 is incorrect: The Indian Forest Act, 1927, was amended in 2017 to exclude bamboo grown on non-forest land from the definition of "tree," thereby allowing its free cultivation and transportation. However, this amendment does not grant forest dwellers the right to fell bamboo grown on forest areas. Bamboo in forest areas is still regulated under forest laws.

Statement 2 is correct: The Forest Rights Act (FRA) of 2006 recognizes bamboo as a minor forest produce (MFP).

Statement 3 is correct: The FRA, 2006, grants forest dwellers the right to own, collect, use, and dispose of minor forest produce (MFP). This includes bamboo, tendu leaves, honey, and other non-timber forest products.

Explanation

Laws to manage e-waste have been in place in India since

2011 under The e-Waste (Management and Handling) Rules, 2011, which was amended in 2016 as E-waste (Management) Rules, 2016. It recognises producers’ liability for recycling and reducing e-waste in the country. Extended Producer Responsibility (EPR) is a policy approach under which producers are given a significant responsibility - financial and/or physical - for the treatment or disposal of post-consumer products. The Central Pollution Control Board (CPCB) has been given the Extended Producer Responsibility (EPR) authorisation under the new e-waste rules.