Environmental Science MCQ – Asked in Previous Years, WBCS Mains

Answer – D. 3%
Explanation-The Mangrove forests of India constitute approximately 3% of the total mangrove forests of the world. India has a significant coastline along the Bay of Bengal and the Arabian Sea, which supports diverse mangrove ecosystems. Mangrove forests are important coastal habitats that provide numerous ecological benefits, including coastal protection, carbon sequestration, and habitat for various marine and avian species.

Answer – D. Water footprint
Explanation-The direct and indirect water usage associated with an individual, product, or activity is called the water footprint. It is a measure of the total volume of freshwater used to produce goods and services, including both direct water consumption and the indirect water embedded in the supply chain. The water footprint considers water consumption at various stages, such as agricultural production, industrial processes, and personal consumption, providing insights into the water-related impacts of human activities.

Answer – B. Pacific Ocean
Explanation-The Pacific Ocean is the most active area for tsunamis in the world. This is because the Pacific Ocean is home to the Ring of Fire, a belt of volcanoes and fault lines that encircles the Pacific Ocean. Earthquakes and volcanic eruptions along the Ring of Fire are the most common causes of tsunamis. The Atlantic Ocean is the second most active area for tsunamis, followed by the Indian Ocean and the Mediterranean Sea. The Bay of Bengal is not a particularly active area for tsunamis. However, the Bay of Bengal was hit by a devastating tsunami in 2004, which killed over 230,000 people. Here is a table showing the number of tsunamis that have occurred in each ocean since 1900:

Answer – D. Methane
Explanation-Methane is not considered a persistent organic pollutant (POP). POPs are toxic chemicals that persist in the environment, bioaccumulate in organisms, and can have adverse effects on human health and ecosystems. Examples of POPs include DDT (dichlorodiphenyltrichloroethane), dioxins, and endosulfan. Methane, on the other hand, is a greenhouse gas and a significant contributor to climate change, but it is not classified as a persistent organic pollutant.

Answer – C. Bhutan
Explanation-Bhutan is known for being carbon negative in nature. It means that the country’s carbon emissions are lower than its carbon sequestration and removal from the atmosphere. Bhutan places a strong emphasis on environmental conservation and sustainable development. The country’s abundant forests, which cover over 70% of its land area, act as a carbon sink, absorbing more carbon dioxide than the country emits.

Answer – D. UK
Explanation-The first Eco-city of the world was built in the UK. The city is called “BedZED” (Beddington Zero Energy Development) and is located in London, England. BedZED is a sustainable housing development designed to minimize its ecological footprint. It incorporates various eco-friendly features, including renewable energy systems, energy-efficient buildings, water conservation measures, and sustainable transportation options.

Answer – D. 1989
Explanation-The Basel Convention, an international treaty on the control of hazardous wastes, was adopted in 1989. It aims to minimize the generation, transboundary movement, and disposal of hazardous wastes to protect human health and the environment. The convention establishes guidelines for the environmentally sound management of hazardous wastes, including their collection, treatment, and disposal.

Answer – B. 2001
Explanation-The Energy Conservation Act was introduced in India in 2001. The act aims to promote energy efficiency and conservation in various sectors of the economy. It provides a legal framework for the implementation of energy efficiency measures, energy audits, energy labeling, and other initiatives to reduce energy consumption and promote sustainable energy practices.

Answer – A. London
Explanation-The “London Convention,” formally known as the “Convention on the Prevention of Marine Pollution by Dumping of Wastes and Other Matter 1972,” is one of the earliest international agreements established to safeguard the marine environment against harmful human activities. It has been effectively enforced since 1975.

Answer – B. Eubacteria
Explanation-Eubacteria are a large group of bacteria that are found in all environments, including aquatic, terrestrial, and even extreme environments. Some eubacteria are capable of converting mercury to methylmercury. This process is called methylation. Methylmercury is a highly toxic form of mercury that can accumulate in the food chain. It is a major health hazard for humans and animals. The other options are incorrect. Cyanobacteria are a type of bacteria that are found in aquatic environments. Fungi are not capable of methylating mercury. Algae are a type of plant that are found in aquatic environments. They are not capable of methylating mercury either.