Changes in environment affect us and our activities change the environment around us. Environmental problems caused by humans:
- depletion of the Ozone Layer and waste disposal.
- pollution due to mismanagement of waste disposal.
Depletion of Ozone Layer
- Ozone (O3) layer is largely found in the stratosphere which is a part of our atmosphere from 12 km – 50km above sea level.
- Ozone is a deadly poison at the ground level.
- Ozone layer is a protective blanket around earth which absorbs most of the harmful U.V. (Ultraviolet) radiation of the Sun, thus protecting the living beings of the earth from health hazards like skin cancer, cataract in eyes, weaken immune system, destruction of plants etc.
- The decline of Ozone layer thickness in Antarctica was first observed in 1985 and was termed as Ozone Hole.
Reason of Ozone Depletion
Excessive use of CFCs (Chloro Flouro Carbon) a synthetic, inert chemical E.g. Freon which are used as refrigerants and in fire extinguishers, caused Ozone depletion in the upper atmosphere. A single chlorine atom can destroy 1,00,000 Ozone molecules. U.N.E.P. (United Nation Environment Program) did an excellent job in forging an agreement to freeze CFC production at 1986 levels (KYOTO Protocol) by all countries.
Industrialization and rise in demand of consumer goods have created a major problem in the form of wastes/garbage accumulation and its disposal specially in urban area. The different methods of solid wastes disposal commonly used around the world are.
- Open dumping: A conventional method in which solid wastes dumped in selected areas of a town. It actually causes pollution
- Land fillings: Wastes are dumped in low living area and are compacted by rolling with bulldozers
- Composting: Organic wastes are filled into a compost pit (2m × 1m× 1m). It is then covered with a thin layer of soil. After about three months the same garbage filled inside the pit changes into organic manure.
- Recycling: The solid wastes is broken down into its constituent simpler materials. These materials are then used to make new items. Even non-bio degradable solid wastes like plastic, metal can be recycled.
- Reuse: A very simple conventional technique of using an item again& again. For e.g. paper can be reused for making envelops etc.