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Question
Observe figure and answer the following questions.
Biomagnification of DDT in an aquatic food chain
- What ecological term is used to describe the DDT accumulation at different trophic levels?
- List any one effect of DDT accumulation on birds
- Will DDT accumulation lead to eutrophication?
- Does it affect the BOD?
- Name disease caused by accumulation of any heavy metal.
Solution
- Biomagnification
- High concentrations of DDT disturb, calcium metabolism in birds, which causes thinning of eggshells and their premature breaking, eventually causing decline in bird populations.
- Yes.
- Yes, it increases the BOD.
- Disease caused by eating fish found in water contaminated with industrial waste having mercury is Minamata disease. Cd pollution associated with the disease is called “Itai-Itai”. Arsenic (As) poisoning causes "Black foot disease".
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