BIO MAGNIFICATION

Bio magnification is a process by which some pollutants fail to degrade inside the bodies of animals , remaining unchanged and becoming concentrated in successive trophic levels in food chain or food web.
When chemicals obtained as part of food fail to degrade( eg.mercury) or degrade slowly ( eg DDT), they remain accumulated in the body tissues. When plant tissues accumulate such substances, they get passed on to the animals eating them. The small amounts of these chemicals from different plants add up and accumulate in higher quantities in animal tissues. These animals are then inturn eaten by other animals, where the chemicals get further concentrated. This process of increasing concentration of chemicals in organisms at the higher levels of a food chain is called biomagnification. The higher an organism is in the food chain, the greater the concentration of chemicals. 
A classic example of biomagnification is Minimata disease, which affected the fisher folk of Minimata Bay ,Japan ,as a result of eating fish contaminated by mercury.
The process of biomagnification is shown through an example. The numbers represent the quantity of substances that do not break down. Producers ------>primary conumers ---->
(Planktons)        (aquatic insect larva)
O.05ppm               0.26ppm            
 secondary consumers ------> tertiary
(Fish)                                      (brahmny kite)
3.00ppm                              14.73ppm
 consumers 

  

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