Railway Science (Environment – Miscellaneous)

Sustainable Development - meeting the needs of the present without compromising the ability of future generations to meet their own needs. This definition is given by the Brundtland Commission.
SDGs (Sustainable Development Goals) are a collection of 17 global goals, and their 169 targets, set by the United Nations General Assembly (UNGA) in 2015 for the year 2030 (UNGA resolution “2030 Agenda”). Aimed at improving the quality of human life around the world.

World Wildlife Fund (WWF) - It is the world's largest conservation organization, established in 1961 and headquartered at Gland, Switzerland.

Carbon monoxide (CO) - A poisonous, flammable gas that is colorless, odorless and tasteless. Biogas - The mixture of different gasses produced by the breakdown of organic matter in the absence of oxygen.
It contains methane (50-75%), carbon dioxide (25-50%), nitrogen (2-8%) and traces of hydrogen sulfide, ammonia, and hydrogen .

Biogas - A renewable fuel that's produced when organic matter, such as food or animal waste, is broken down by microorganisms in the absence of oxygen. It contains Methane gas (CH₄), Carbon dioxide (CO₂) and amounts of Nitrogen (N₂), Hydrogen (H₂).

Bio-geographic regions were originally identified by Philip L Sclater and H.G. Adolf Engler. At first, six regions were identified - Palearctic (Europe and Asia), Nearctic (North America), Neotropical (Mexico, Central America, and South America), Ethiopian (Africa), Indian (Southeast Asia and Indonesia), Australian (Australia and New Guinea). Later, two more were added - Oceania (Polynesia, Fiji, and Micronesia), Antarctica.

Earth's original atmosphere was rich in methane, ammonia, water vapor, and the noble gas neon, but it lacked free oxygen. Composition of Earth's atmosphere: Nitrogen (N₂) - 78%, Oxygen (O₂) - 21%, Argon (Ar) - 0.9%, and other gases - (0.1%).