Environment and Environmental Problems Part-2
- It is formed by interconnections of different food chains.
- It shows in graphic form "Who Eats Whom" in an ecosystem.
- Due to the interlinking of food chains, food webs are never straight.
- The food web offers additional pathway for food availability. In the event that one species is wiped out, the predator could feed on a different species.
- The concentration of harmful chemical increases with every next trophic level in a food chain. It is called Bio-magnification
- The human body accumulates these substances at the highest quantity. Since humans occupy the top level in any food chain.
- Changes in environment affect us and our activities change the environment around us. Environmental problems caused by humans:
- (a) Depletion of the Ozone Layer and waste disposal.
(b) Pollution due to mismanagement of waste disposal.
- High UV radiation breaks down oxygen into oxygen atoms. These oxygen atoms when combine with oxygen, they form ozone.
Depletion of Ozone Layer
- The ozone layer protects the Earth from the sun’s ultraviolet (UV) radiation.
- In 1985, it was discovered that the ozone layer's thickness over Antarctica had dropped. This is defined as ozone depletion and was termed as Ozone hole.
- The overuse of chlorofluorocarbons in aerosols, air conditioners, and other products leads to ozone depletion.
- Ozone is formed as a result of a following photochemical reaction.
- Ozone depletion would allow ultraviolet rays to enter the earth's atmosphere, resulting in blindness, skin cancers, and genetic abnormalities.
Reason of Ozone Depletion
- Ozone depletion in the upper atmosphere was caused due to excessive usage of CFCs (Chloro Flouro Carbon), a synthetic, inert chemical, such as Freon, which are used as refrigerants and in fire extinguishers.
- A single chlorine atom can destroys 1, 00,000 Ozone molecules.
- A great work was done by U.N.E.P. (United Nations Environment Programme) in negotiating the Kyoto Protocol, which demands that all nations' CFC production must stop at levels last seen in 1986.
- Involves all the activities and actions required to manage waste from its inception to its final disposal.
- Ensures environmental best practices are followed along with proper monitoring and regulation.
Methods of Waste Management
- Incineration: Burning of waste on high temperature to form ash is called incineration. This process is carried out in an incinerator. Incineration is used to destroy household, chemical and biological wastes.
- Open dumping: A conventional method in which solid wastes dumped in selected areas of a town. It actually cause pollution
- Land fillings: Wastes are dumped in low living areas 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 are 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 and again. For example; paper can be reused for making envelops, etc…