Daily Quiz: UPSC Prelims Marathon – March 14, 2020

Biosphere has three basic components. These are (A) abiotic (physical and inorganic) components; (B) biotic (organic) components and (C) energy components. Let us discuss about these three components in detail. (A) Abiotic Components: These components broadly consist of all non-living elements which are essential for the survival of all living organisms. These are (i) lithosphere (solid part of the earth crust), (ii) atmosphere and (iii) hydrosphere. Mineral nutrients, certain gases and water are the three basic requirements of organic life. Soils and sediments constitute the chief reservoir of mineral nutrients. Atmosphere constitutes the chief reservoir of gases essential for organic life. Ocean constitutes the chief reservoir of liquid water. Where all these three reservoirs intermingle and that area becomes the most fertile area for organic life. The upper layer of the soil and shallow parts of the ocean constitute the most important areas, box sustaining organic life. The upper layer of soil, permits easy penetration of gases and percolation of moisture, while shallow parts of oceans, allow penetration of sunlight, intermingling of dissolved gases and nutrients from land surface and ocean bottoms.

Ozone constitutes only less than 0.002 percent of the volume of the atmosphere. However, it’s role is very critical as far as lives on the earth is concerned. It strongly absorbs ultraviolet radiation from the sun. Ultraviolet radiation is biologically destructive in many ways. It causes skin cancer and cataracts, suppresses the human immune system, dimimshes the yield of many crops, disrupts the acquatic food chain by killing micro-organisms on the ocean surface and many other negative effects which is still undiscovered. This is happening due to certain recent human activities which have injected certain chemicals in the stratosphere which consume ozone and reduce its concentration. Depletion is mainly caused by chlorofluorocarbons (CFCs), halons, methyl chloroform and carbon tetrachlorides. These chemical substances are mainly either chlorine or bromine which can reach the stratosphere and catalytically break down ozone into oxygen. CFCs are odourless, non-flamable, non-corosive and nontoxic. For this reason, scientist originally believed CFCs could not possibly have any effect on the environment. That is why it is widely used in refrigeration and air conditioning, in foam and plastic manufacturing and in aerosol sprays. It needs certain actions both at individual as well as governmental level. Since the last two decades, certain actions have been initiated at global level. Among these Montreal Protocol of 1987 and London Conference of 1992 are important. In both these conferences it was decided that the developed countries would totally ban CFC production by 2000 and the developing countries by 2010AD.

The term ‘acid rain’ refers to the deposition of wet or dry acidic materials from the atmosphere on the earth’s surface. Although most conspicuously associated with rainfall, the pollutants may fall on the earth’s surface either in the form of snow, sleet, hail or fog or in the dry form of gases or particulate matter. Sulphuric acid and nitric acid is considered as the principal agents responsible for acid rain. But the major culprits are human beings. Smokes emitted from the industries are the major source of sulphur dioxide whereas smokes emitted from the motor vehicle is the major source of nitrogen oxide. These emissions mixed with atmospheric moisture from the sulphuric acid and nitric acids which, sooner or later precipitate on earth in various form.

The CSIR-National Environmental Engineering Research Institute (CSIR-NEERI) is a research institute created and funded by Government of India. It was established in Nagpur in 1958 with focus on water supply, sewage disposal, and communicable diseases and to some extent on industrial pollution and occupational diseases found common in post-independent India. NEERI is a pioneer laboratory in the field of environmental science and engineering and part of Council of Scientific and Industrial Research (CSIR). NEERI has five zonal laboratories at Chennai, Delhi, Hyderabad, Kolkata and Mumbai. NEERI falls under the Ministry of Science and Technology (India) of central government. The NEERI is an important partner organization in India’s POPs national implementation plan (NIP).

In the 1980s the UN set up the Commission on Environment and Development, also known as the Brundtland Commission, named after its Chair Gro Harlem Brundtland. The outcome of the Brundtland Commission was a comprehensive document entitled “Our Common Future”, otherwise known as the Brundtland Report. This report framed much of what would become the 40 chapters of Agenda 21 and the 27 principles of the Rio Declaration on Environment and Development.