Test: Environment- 1 - UPSC MCQ

• Oxo-degradable/oxy-degradable/ oxo-biodegradable plastics are conventional plastics such as PE, which include an additive to help them break down into smaller fragments, which could lead to microplastic leakage in the environment.
• Oxo-degradable plastics are made of petroleum-based polymers (usually polyethylene (PE)) and contain special additives that cause them to degrade.
• Oxo-biodegradable polymers have been used to produce plastic bags. Exposure of this waste plastic to ultraviolet light (UV) or heat can lead to the breakage of the polymer chains in the plastic, and microorganisms easily degrade the resulting compounds.

So, Option (c) is correct.

• Kanger Ghati National Park is located in Chattisgarh, not Odisha. The Chhattisgarh government has become the country’s second state to recognize the Community Forest Resource (CFR) after Simlipal in Odisha, rights of a village inside a national park. The CFR rights of tribals living in Gudiyapadar, a hamlet inside the Kanger Ghati National Park in Bastar district, were recognized Wednesday, giving the community power to formulate rules for forest use. According to state government officials, Chhattisgarh has recognized nearly 4,000 CFR rights in the state. So, Statement 1 is not correct.
• Ladakh is home to the Hemis National Park, the largest notified protected area in India or simpler terms, the largest national park in India. Hemis National Park was first established as a national park in 1981, with a total area of approximately 600 sq km. Slowly, the park area increased to a whopping 4,400 sq km, making it the largest national park not only in India but also in the whole of South Asia. Hemis National Park is one of the most important natural habitats for the snow leopard. At present, there are about 200 snow leopards that share this national park with other animal species like the Tibetan wolf, Eurasian brown bear, red fox, Himalayan marmot, Argali or the great Tibetan sheep, Bharal or the blue sheep, Shapu or the Ladakhi wild sheep, and Asiatic ibex to name a few. So, Statement 2 is correct.
• IUCN protected area categories, or IUCN protected area management categories, are categories used to classify protected areas in a system developed by the International Union for Conservation of Nature (IUCN). This categorization method is recognized on a global scale by national governments and international bodies such as the United Nations and the Convention on Biological Diversity. These categories include:
  • Category Ia – Strict nature reserve is an area that is protected from all but light human use in order to protect its biodiversity and also possibly its geological/geomorphic features.
  • A wilderness area (IUCN Category Ib) is similar to a strict nature reserve but generally larger and protected in a slightly less stringent manner.
  • A National Park (IUCN Category II) is similar to a wilderness area’s size and the main objective of protecting functioning ecosystems. However, national parks tend to be more lenient with human visitation and its supporting infrastructure.
  • A natural monument or feature (IUCN Category III) is a comparatively smaller area that is specifically allocated to protect a natural monument and its surrounding habitats. These monuments can be natural in the fullest sense or include elements that have been influenced or introduced by humans.
  • A habitat or species management area (IUCN Category IV) is similar to a natural monument or feature. Still, it focuses on more specific areas of conservation (though the size is not necessarily a distinguishing feature), like an identifiable species or habitat that requires continuous protection rather than that of a natural feature. 3⁄
  • A protected landscape or protected seascape (IUCN Category V) covers an entire body of land or ocean with an explicit natural conservation plan but usually also accommodates a range of for-profit activities. The main objective is to safeguard regions that have built up a distinct and valuable ecological, biological, cultural, or scenic character.
  • Category VI – a protected area with sustainable use of natural resources.

So, Statement 3 is correct.

• Dead plant remains such as leaves, bark, flowers and dead remains of animals, including fecal matter, constitute detritus, the raw material for decomposition.
• The detritus food chain (DFC) begins with dead organic matter. It comprises decomposers, which are heterotrophic organisms, mainly fungi and bacteria. They meet their energy and nutrient requirements by degrading dead organic matter or detritus. These are also known as saprotrophs (sapro: to decompose).
• Decomposers secrete digestive enzymes that break down dead and waste materials into simple, inorganic materials that they absorb. Detritivorous animals include millipedes, springtails, woodlice, dung flies, slugs, terrestrial worms, sea stars, sea cucumbers, fiddler crabs, and some sedentary polychaetes such as worms of the family Terebellidae.

So, Option (b) is correct.

• FACT dialogue is a government-to-government dialogue informed by a multi-stakeholder task force in 2021. It held discussions on four thematic and related areas: trade and market development; smallholder support; traceability and transparency; and research, development, and innovation. Informed by the principles of collaboration, the four thematic working groups, under the leadership of co- facilitators, shared ideas, exchanged best practices and discussed actions that countries could take forward in collaboration. So, Statement 1 is correct.
• Issues of trade and markets lie at the heart of the FACT Dialogue. An important priority is to secure and grow market share for sustainably produced agricultural commodities. Collaboration at the global level is crucial, as both demand and supply side measures are needed. The FACT Dialogue seeks to reverse deforestation and accelerate the transition towards more sustainable land-use practices, specifically through dialogue. FACT brings together the largest producers and consumers of internationally traded agricultural commodities (such as palm oil, soya, cocoa, beef and timber) in order to protect forests and other ecosystems while promoting trade and sustainable development. So, Statement 2 is correct.
• The Tropical Forest Alliance is a multistakeholder partnership platform initiated to support the implementation of private-sector commitments to remove deforestation from palm oil, beef, soy and pulp/paper supply chains. Hosted by the World Economic Forum, the 170+ alliance partners include companies, government entities, civil society, indigenous peoples, local communities and international organizations, working together through Forest-Positive Collective Action to advance the world’s transition to deforestation-free commodity supply chains. This project is part of the World Economic Forum’s Centre for Nature and Climate and Climate Action Platform Platforms.

So, Statement 3 is correct.

• Solid wastes should be properly disposed by composting, land filling, thermal processes; and by re- cycling and re- use.
• Composting is the process of degrading decomposable solid waste in a properly dug pit, called as compost pit. Composting process involves both the aerobic and anaerobic processes. Hence, statement 1 is correct.
  • In aerobic composting the biodegradable wastes are filled in the compost pit which is left open from one or more sides.
    • On the other hand, in anaerobic composting the biodegradable wastes are allowed to degrade in sealed compost pits. The compost prepared through any one of these processes is very good manure for crops.
• Land filling is just the process of dumping wastes or other substances in low land areas and covering the same with soil. This is the age old practice of leveling low areas. But, in modern times waste materials are buried under soil after compacting them properly in a scientific manner. The provision of release of gases from the decomposing materials of the land fill is also made adequately. Hence, statement 2 is correct.
• In thermal process, the dried solid waste is safely burnt in closed compartments with proper provision of treatment of harmful gases, and utilization of heat energy evolved during the process. It is called as incineration. Hence, statement 3 is correct.
• Environmentalists do not favour this process of solid waste treatment in view of fear of air pollution, rather they advocate for re-cycling and re-use for the disposal of non- biodegradable substances.

• Bioremediation: The application of biotic agents like microorganisms in the correction and recovery of environmental damage is called as bioremediation. The removal of oil spilled on sea water by the help of bacteria is one example of bioremediation.
• Bioaccumulation: Increase in concentration of a substance within a trophic level in certain tissues of organisms' bodies due to absorption from food and the environment is called bioaccumulation.
• Biomagnification: Increase in concentration of a substance in the bodies of consumers as one moves up the food chain is called biomagnification. For example, when chemicals or pesticides are let into rivers or lakes they are consumed by aquatic organisms like fish, which in turn are consumed by large birds, animals or humans.
• Biopiracy: The practice of commercial exploitation of biochemicals or genetic materials which occur naturally. It is the unethical or unlawful appropriation or commercial exploitation of biological materials
• Hence, option (b) is the correct answer.

The Correct Answer is B :- All three

Statement 1 Correct

• Lianas (also known as vines, climbing plants or climbers) are plants with long, flexible, climbing stems that are rooted in the ground, and usually have long dangling branches.
• They particularly thrive in disturbed forest areas — such as those affected by logging, natural treefalls, landslides —because they can quickly grow towards the forest canopy using trees as support.

Statement 2 Correct

• Lianas, or woody vines, have been referred to as structural or mechanical parasites.
• Although they are rooted in the soil, they depend upon host plants or other external objects for their mechanical support Studies suggest that lianas may be detrimental to the host trees.

    Statement 3 Correct

•  Lianas use their climbing ability, resilience to climatic stress, and efficient water and nutrient usage to outcompete trees for sunlight and resources.
• They compete for sunlight in the canopy and suppress trees.
• Their lower carbon sequestering capacity compared to trees further exacerbates the threat to carbon storage.

Statement 1 and 2 are correct:

What is Ambergris?

• Ambergris means grey amber in French, is a waxy substance that originates from the digestive system of sperm whales.
• The freshly passed ambergris is a light yellowish substance and is fatty but as it ages it turns waxy and gets red-brownish, sometimes with shades of grey and black in colour and attains a mild, earthy, sweet smell but still with notes of mild marine odour.
• Due to its high value in the market, ambergris is often called the ‘floating gold’ and ‘treasure of the sea’.
• Ambergris is a rare substance, which contributes to its high demand and high price in the international market.
• Traditionally, it is used to produce perfumes which have notes of musk.

Statement 3 is not correct: There is a ban on the possession and trade of ambergris in countries like the USA, Australia and India but in several other countries it is a tradable commodity, though with limitations in some of them.

• Filter feeding is a form of food procurement in which food particles or small organisms are randomly strained from water. Filter feeding is found primarily among small- to medium-sized invertebrates but occurs in a few large vertebrates.
• Some filter feeders are sessile organisms - they don't move much, if at all. Example : tunicates (sea squirts), bivalves (e.g., mussels, oysters, scallops), tubeworm and sponges. Bivalves filter-feed by straining organic matter from the water using their gills. This is accomplished using cilia, thin filaments that beat to produce a current over water over the gills.
• Additional cilia remove the food. Some filter feeders are free-swimming organisms that filter the water while swimming or even actively pursue their prey.
• Examples of these filter feeders are basking sharks, whale sharks, and baleen whales. Basking sharks and whale sharks feed by swimming through the water with their mouths open.
• The water passes through their gills, and food is trapped by bristle-like gill rakers. Baleen whales feed either by skimming the water and trapping prey on the fringe-like hairs of their baleen or gulping in large quantities of water and prey and then forcing the water out, leaving prey trapped inside.

So, Option (d) is correct. 

• Diatoms and dinoflagellates are types of phytoplankton. They are single-celled algae.
• Diatoms have a thick cell covering, which acts as an external cell wall made up of silica and Dinoflagellates have a bi-flagellated structure with cellulose-based cell walls. Both are capable of performing photosynthesis and possess pigments.
• Dinoflagellates have special features, such as the ability to produce neurotoxins and the ability for bioluminescence. Both diatoms and dinoflagellates are motile (Cell motility is an essential process in many biological phenomena.
• Different molecules and pathways have been linked to cell migration, but very little is known about how they are integrated in time and space to regulate the motility process).

So, Option (c) is correct.

• Foraminifera is amoeba-like, single-celled protist (very simple micro-organisms). They have been called 'armored amoebae' because they secrete a tiny shell (or 'test'), usually about a half and one millimeter long. Foraminifera is found in all marine environments, from the intertidal to the deepest ocean trenches and from the tropics to the poles, but species of foraminifera can be very particular about the environment in which they live. They may be planktic or benthic in their mode of life. So, Statement 1 is correct.
• Copepods are major secondary producers in the World Ocean. They represent an important link between phytoplankton, microzooplankton and higher trophic levels, such as fish. They are an important food source for many fish species but also a significant producer of detritus. So, Statement 2 is not correct.
• Sea otters are part of the weasel family. They have webbed feet, water-repellent fur to keep them dry and warm, and nostrils and ears that close in the water. Sea otters live in shallow coastal waters of the North Pacific Ocean. They are among the select group of animals known to use tools. They use rocks or other objects to pry shellfish from hard surfaces and hammer them open or as an anvil against which to break their shells. Sea otters were hunted for their fur to the point of near extinction.

So, Statement 3 is correct.

• Pinus longifolia or Pinus Roxiburghii, commonly known as long-leaved pine or chir pine is one of the most important conifers in the Himalayan region.
• Chirpine is also known as three-needled Indian pine, a native of the Himalayas that is spread across Afghanistan, Pakistan, Nepal and India. It grows between lower elevations of 500 metres to higher elevations of 2,200 meters and forms a pure forest.
• While the upper elevation of chirpine touches the associate tree species like Banj oak, Deodar, Kail, Rhododendron, at its lower elevation, the tree touches Sal, kahir, Harad, Bahed, among others.
• Chirpine is a large evergreen tree with an elongated crown that attains a height of up to 50 meters, with about 3.5 meters in girth, and forms a straight cylindrical bole. It is one of India's six pines with maximum occurrence and area.

So, Option (b) is correct. 

• Statement 1 is correct: Blue hydrogen is hydrogen produced from natural gas with a process of steam methane reforming, where natural gas is mixed with very hot steam and a catalyst. It split into hydrogen and carbon dioxide.
• Statement 2 is correct: Green hydrogen derived from water electrolysis using renewable electricity.
• Statement 3 is correct: Brown hydrogen is formed through coal gasification.

• The microbial action on solid wastes breaks it into simpler form. Some of the waste matter is converted into gases (mostly carbon dioxide, CO₂) and the rest becomes simple to be taken in by plants.
• Aerobic bacteria decompose solid wastes in air and produce carbon dioxide. They absorb nitrogen, carbon and phosphorus from the decomposed wastes. Anaerobic decomposition occurs in the absence of oxygen. Anaerobic bacteria give out enzyme which breaks down the wastes and produce Methane or Marsh Gas (CH₄). The sulphur content is converted into sulphur dioxide (SO₂). Hence, statement 1 is correct.
• The nutrients like nitrogen, phosphorus and carbon etc. are then taken in by anaerobic bacteria. Very much heat (upto 80°C) is produced due to anaerobic decomposition. It kills seeds of weeds and germs present in the waste. The solid waste, for this type of decomposition has to be covered in a pit properly to cut off oxygen supply from the air. Hence, statement 2 is correct.

• Irreparable computers and other electronic goods are known as electronic wastes (e-wastes). E- wastes are burried in landfills or incinerated.
• Over half of the e-wastes generated in the developed world are exported to developing countries, mainly to China, India and Pakistan, where metals like copper, iron, silicon, nickel and gold are recovered during recycling process. • Unlike developed countries, which have specifically built facilities for recycling of e-wastes, recycling in developing countries often involves manual participation thus exposing workers to toxic substances present in e-wastes.
• E-waste-connected health risks may result from direct contact with harmful materials such as lead, cadmium, chromium, brominated flame retardants or polychlorinated biphenyls (PCBs), from inhalation of toxic fumes, as well as from accumulation of chemicals in soil, water and food. In addition to its hazardous components, being processed, e-waste can give rise to a number of toxic by-products likely to affect human health. Furthermore, recycling activities such as dismantling of electrical equipment may potentially bear an increased risk of injury.
• Hence option (c) is the correct answer.

• A National Park is an area protected and preserved by law to protect and preserve flora and fauna within its boundary. Grazing of cattle and removal of any wildlife from its habitat is strictly prohibited in a national park and all rights are reserved with the government.
• A Sanctuary is a protected area where wild animals and birds are kept and encouraged to increase their population. In wildlife sanctuaries, rare and endangered species are encouraged to breed in human- controlled environments with restricted settings.
• Differences between a National Park and Wildlife Sanctuary:
  • A National Park is established by the government in view of the protection of all the flora and fauna of certain areas. But a Wildlife sanctuary is meant for the protection, breeding and propagation of individuals of an endangered species.
  • The boundaries of a National Park are usually well-marked and circumscribed whereas those of sanctuaries are often not well-defined and human activities are permitted to a specified limit. Hence statement 2 is correct.
  • A National Park is established under the provisions of Section 35, section 38(2), and Section 66(3) of the Wild Life (Protection) Act of 1972. On the other hand, a Wildlife Sanctuary is an area that is established under the provisions of Section 26-A, Section 38(1), and Section 66(3) of this Act.
  • An area can not be notified as a National Park if it is a reserve Forest. However, this is not the case with a Wildlife Sanctuary in which an area can directly be notified as a Wildlife Sanctuary even if it is a reserve forest.
  • National parks are given a greater degree of protection, with human activity greatly restricted. Sanctuaries have relatively less restrictions and are open to people, without the requirement of official permission. Hence statement 1 is correct.
• In spite of some differences, National Parks and Wildlife Sanctuaries have basic similarities.
  • The Wildlife (Protection) Act (WPA) of 1972 provided for the declaration of National Parks by the State Government in addition to the declaration of wildlife sanctuaries. The Central Government may also declare, Wild Life Sanctuary and National Park under certain conditions. Hence statement 3 is not correct.
  • It can be said that both the National Park and the Wildlife Sanctuary are protected areas, and no biotic interference is allowed in both of these areas. 

• Ionizing radiations: Electromagnetic radiations such as short wavelength ultra violet radiations (UV), X-rays and gamma rays and energetic particles produced in nuclear processes, electrically charged particles like alpha and beta particles produced in radioactive decay and neutrons produced in nuclear fission, are highly damaging to living organisms. Hence, statement 1 is not correct.
• Electrically charged particles produced in the nuclear processes can have sufficient energy to knock electrons out of the atoms or molecules of the medium, thereby producing ions. The ionizing radiations cause damage to biological systems and are, therefore are pollutants. Hence, statement 2 is correct.
• A gamma ray passing through a cell, can ionise the water molecules near the DNA. These ions might react with the DNA causing it to break. They can also cause chemical changes by breaking the chemical bonds, which can damage living tissues.Hence, statement 3 is correct.

• Coral reefs are often referred to as the medicine chests of the sea. A number of creatures found on reefs produce chemical compounds that have been isolated to treat human diseases—and researchers believe that many more are yet to be discovered. Soft corals, in particular, have been found to possess compounds that could be used to treat various types of cancers. E.g., Secosteroids and Norcembranoids from the Soft Coral Sinularia nanolobata. So, Statement 1 is correct.
• Corals are invertebrate animals belonging to a large group of colorful and fascinating animals called Cnidaria. Coral has a symbiotic relationship (each gives something to the other and gets something back in return) with 'zooxanthellae'microscopic algae which live on coral. The corals are generally slow-growing colonies of animals, while zooxanthellae are fast-growing plants. So, Statement 2 is not correct.
• The Coral Reef Alliance (CORAL) is a non-profit environmental NGO that is on a mission to save the world's coral reefs. Working collaboratively with communities to reduce direct threats to reefs in ways that provide lasting benefits to people and wildlife. Thus Coral Reef Alliance (CORAL) is not an environmental intergovernmental organization. So, Statement 3 is not correct.
• Corals are marine invertebrates that attach themselves to rocky intertidal regions or the ocean floor and are carnivorous animals. Corals are Schedule 1 species under the Wildlife Protection Act, 1972, meaning corals have the same protection as that of a tiger or a leopard. They were booked under sections 9, 39, 40, 44, 48, 49A of the Wildlife Protection Act 1972. The quantum of punishment can lead to three to seven years of jail. So, Statement 4 is correct.

• Black carbon, or soot, is part of fine particulate air pollution (PM2.5) and contributes to climate change. Black carbon is formed by the incomplete combustion of fossil fuels, wood and other fuels.
• Complete combustion would turn all carbon in the fuel into carbon dioxide (CO_²), but combustion is never complete, and CO₂, carbon monoxide, volatile organic compounds, and organic carbon and black carbon particles are all formed in the process.
• The complex mixture of particulate matter resulting from incomplete combustion is often referred to as soot. Brown carbon (BrC), a carbonaceous aerosol that absorbs solar radiation over a broad range of wavelengths, is beginning to be seen as an important contributor to global warming.
• It absorbs both inorganic and organic pollutants, leading to serious effects on human health. Atmospheric “Brown Carbon” (BrC) is a complex mixture of organic compounds with diverse compositions and variability of its light-absorbing properties. BrC formed by incomplete combustion of fossil fuels and biomass is an important contributor to the light absorption by atmospheric aerosols. So, Option (a) is correct.

• Epiphyte, also called air plant, is any plant that grows upon another plant or object merely for physical support. Epiphytes have no attachment to the ground or other obvious nutrient sources and are not parasitic on the supporting plants. Aerial roots of epiphytes are greenish and covered with spongy tissue (Velamen) with which they absorb atmospheric moisture. So, Statement 1 is correct.
• Approximately 70 percent of all orchids are epiphytes, plants that grow on other plants. Epiphytic orchids are largely confined to the tropics and subtropics, where day length and the aspect of the sun vary little with the seasons and temperature ranges are generally stable and above freezing. In contrast, almost any part of a tree can be host to epiphytic orchids. So, Statement 2 is correct.
• Botanical Survey of India published the first comprehensive orchid census of the country last year, and Arunachal Pradesh emerged as its top contributor. Unsurprisingly, nearly half (612 out of 1256) of India's orchid species can be found in the Northeastern state. In Arunachal Pradesh, the richest concentration of orchids is believed to be in Ziro Valley. An orchid translocation project since 2017 has led to the discovery of more than 20 species in the area. Ziro Valley is located in Arunachal Pradesh, not in Himachal Pradesh. So, Statement 3 is not correct.

Butea Monosperma, popularly known as ‘Flame of the forest,’ is in full bloom in rural parts of the district, presenting an enchanting sight. The blooming of this flower also heralds the Spring season. From a distance, it’s like seeing a brightly lit torch, given its bright orange colour. These trees are distinct as they wear more flowers than leaves. During this season, children in rural areas mash the flowers to extract juice, which is then used as a colour to sprinkle on each other on Holi, the festival of colours. Though people cultivate this tree in their compounds, they are mostly found in the wilderness. So, Option (a) is correct.

• Most herbicides are toxic to mammals but are not as persistent as organo-chlorides. These chemicals decompose in a few months. Like organo-chlorides, these too become concentrated in the food web. Some herbicides cause birth defects. Studies show that cornfields sprayed with herbicides are more prone to insect attack and plant disease than fields that are weeded manually.
• Pesticides and herbicides represent only a very small portion of widespread chemical pollution. A large number of other compounds that are used regularly in chemical and industrial processes for manufacturing activities are finally released in the atmosphere in one or other form. Hence, option (a) is the correct answer.

• An ecotone is a zone of junction or a transition area between two biomes (diverse ecosystems). Ecotone is the zone where two communities meet and integrate. For e.g. the mangrove forests represent an ecotone between marine and terrestrial ecosystems
• The edge effect refers to the changes in population or community structures that occur at the boundary of two habitats (ecotone). Sometimes the number of species and the population density of some of the species in the ecotone is much greater than either community. This is called the edge effect. The organisms which occur primarily or most abundantly in this zone are known as edge species. Hence, statement option (a) is not correct.
• Ecocline is a zone of gradual but continuous change from one ecosystem to another when there is no sharp boundary between the two in terms of species composition. Ecocline occurs across the environmental gradient (gradual change in abiotic factors such as altitude, temperature (thermocline), salinity (halocline), depth, etc.). Hence, option (c) is the correct answer.
• A niche refers to the unique functional role and position of a species in its habitat or ecosystem. The functional characteristic of a species in its habitat is referred to as a “niche” in that common habitat. In nature, many species occupy the same habitat, but they perform different functions: Habitat niche – where it lives, food niche – what it eats or decomposes & what species it competes with, Reproductive niche – how and when it reproduces, Physical & chemical niche – temperature, land shape, land slope, humidity & another requirement. Hence, option (b) is not correct.
• Biome is a large regional unit characterized by a major vegetation type and associated fauna found in a specific climate zone. The biome includes all associated developing and modified communities occurring within the same climatic region, e.g., forest biomes, grassland and savanna biomes, desert biome, etc. Hence, option (d) is not correct. 

• Ozone is a gas composed of three atoms of oxygen. It occurs both in the Earth’s upper atmosphere and at ground level. Depending on its location in the atmosphere, it can be good or bad.
• Stratospheric ozone is formed naturally through the interaction of solar ultraviolet (UV) radiation with molecular oxygen (O₂). Here, it forms the "ozone layer," which is approximately 6-30 miles above the Earth's surface. This layer shields us from the harmful UV radiation emanating from the sun. Hence, statement 2 is correct.
• In the troposphere, ozone is formed when heat and sunlight cause chemical reactions between oxides of nitrogen (NOX) and Volatile Organic Compounds (VOC), which are also known as Hydrocarbons. This reaction can occur both near the ground and high in the atmosphere. This ground Ozone is the “bad” ozone and is a secondary air pollutant. It damages crops, trees, and other vegetation and caused severe health problems. Hence statement 3 is not correct.
• In both these processes, Ozone is formed naturally. However, it can also be artificially produced, so that it can be used for water treatment. Ozone generators can create ozone artificially by means of extremely high voltages or by means of UV light. Both methods involve the decomposition of the oxygen molecule. Hence statement 1 is not correct. 

• Polar regions are characterized by the presence of sub-zero temperatures which makes it difficult for a range of animals to survive in such harsh conditions. An overwhelming majority (99 percent) of animals and nearly all plants cannot maintain a constant internal environment in adverse conditions. Heat loss or heat gain is a function of surface area. Since small animals have a larger surface area relative to their volume, they tend to lose body heat very fast when it is cold outside; then they have to expend much energy to generate body heat through metabolism. This is the main reason why very small animals are rarely found in polar regions. Hence statement 1 is correct and statement 2 is not correct.
• Mammals from colder climates generally have shorter ears and limbs to minimize heat loss. This is called Allen’s Rule. In the polar seas, aquatic mammals like seals have a thick layer of fat (blubber) below their skin that acts as an insulator and reduces the loss of body heat. 

• Heat Action Plans aim to provide a framework for implementation, coordination and evaluation of extreme heat response activities that reduces the negative impact of extreme heat. The Plan's primary objective is to alert those populations at risk of heat-related illness in places where extreme heat conditions either exist or are imminent, and to take appropriate precautions, which are at high risk. So, Statement 1 is correct.
• A heat wave is declared if the maximum temperature of a station reaches at least 40 degrees Celsius in the plains, at least 37 degrees in coastal areas and at least 30 degrees in hilly regions, and the departure from normal is at least 4.5 degrees. So, Statement 2 is not correct.

The two main factors taken into account when measuring diversity are richness and evenness. Species richness and species evenness are two components important in measuring the biological diversity of an ecosystem. Both measures describe the species living in a particular area.

• Species richness: It is the number of species within a defined region. Generally, species richness counts the number of species in a particular ecosystem. However, it does not describe the abundance of the species in that particular ecosystem. It’s possible to measure the species richness through either sampling or a census. Hence statement 2 is correct.
• In addition, species richness can be divided into three components:
  • α-Diversity- Alpha diversity refers to diversity within a particular area, community or ecosystem, and is measured by counting the number of taxa (usually species) within the ecosystem.
  • β-Diversity- Beta diversity is species diversity between ecosystems; this involves comparing the number of taxa that are unique to each of the ecosystems.
  • Y -Diversity- Gamma diversity is a measurement of the overall diversity for different ecosystems within a region. o Furthermore, species richness does not describe the distribution of the species within a particular geological area. It only describes the number of species in the above particular geological area. o Species Evenness: It is the number of species and the relative abundance of species in a particular community. There are several indices to describe species evenness and the two most common measures of evenness are the Shannon index (H) and the Simpson index (D). Hence statement 1 is correct.
  • The Shannon index (H) is a measure of the information content of a community rather than that of a particular species. On the other hand, the Simpson index (D) measures the dominance of a multispecies community and can be thought of as the probability that two individuals selected from a community will be of the same species. 

Statement 1 is correct: Teal carbon is indeed stored in non-tidal freshwater wetlands, and it encompasses various forms such as vegetation, microbial biomass, and organic matter.

Statement 2 is correct: India’s first study on teal carbon, conducted at Keoladeo National Park (KNP) in Rajasthan, underscores the significance of wetland conservation in combating climate change. Keoladeo National Park was designated as a UNESCO World Heritage Site in 1985 and was placed on the Montreux Record under the Ramsar Convention due to concerns about water shortages and unbalanced grazing.

• Water pollution is the contamination of water sources by substances that make the water unusable for drinking, cooking, cleaning, swimming, and other activities. Pollutants include chemicals, trash, bacteria, parasites, chemicals, etc.
• The processes that contribute to water pollution include-
  • Agricultural runoff- It includes contaminants such as fertilizers, pesticides, herbicides, etc.
  • Open Defecation- It can cause the release of harmful pathogens in the water body which then contribute to diseases like Typhoid, etc.
  • Discharge of Industrial Effluents- These consist of toxic chemicals, microfibres, and even oil and petroleum.
  • Floods- Floods are destructive in nature and they tend to carry all the material in their way including plastics, mud, etc.
  • Discharge of coolant from Nuclear reactors- The coolant so used tends to be radioactive and can thus result in radioactivity in the water body and aquatic life.
• Hence, option (d) is the correct answer. 

• One of the main problems affecting coastal waters is the high levels of nitrogen and phosphorous-based pollutants entering the water. These pollutants come mainly from human activities. Excessive discharge of nutrients into coastal water results in accelerated phytoplankton growth. Eutrophication is defined as ‘enhanced plankton growth due to excess supply of nutrients. Large growths of phytoplankton are known as blooms and these large blooms can have undesirable effects.
• Biological oxygen demand (BOD) is the amount of dissolved oxygen needed (i.e., demanded) by aerobic biological organisms to break down organic material present in a given water sample at a certain temperature over a specific time period.
• The common lake or stream contains small amounts of oxygen in the form of dissolved oxygen (DO). Dissolved oxygen is a crucial component of natural water bodies, maintaining the aquatic life and quality aesthetic of streams and lakes. So, BOD, indirectly, shows the extent of eutrophication in the water body. Hence, statement 1 is correct.
• The decay of organic matter in water is measured as biochemical oxygen demand. Environmental stresses and other human-induced factors can lessen the amount of dissolved oxygen in a water body, however.
• Biological oxygen demand is essentially a measure of the amount of oxygen required to remove waste organic matter from water in the process of decomposition by aerobic bacteria. Hence, the higher BOD means the presence of higher organic pollution and not inorganic pollution. Hence, statement 2 is not correct.