1. Eutrophication is nutrient enrichment (i.e., addition of nitrates and phosphates) of water body that results in the growth of aquatic plants, especially algae causing colouration of water known as algal bloom. It leads to depletion of dissolved oxygen in water resulting in killing of aquatic organisRead more

    Eutrophication is nutrient enrichment (i.e., addition of nitrates and phosphates) of water body that results in the growth of aquatic plants, especially algae causing colouration of water known as algal bloom. It leads to depletion of dissolved oxygen in water resulting in killing of aquatic organisms (e.g., fish).

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  2. These are substances which cannot be broken down by the activity of microorganisms. These substances go on concentrating at each trophic level of food chain, e.g., DDT and heavy metal (mercury, cadmium, etc.).

    These are substances which cannot be broken down by the activity of microorganisms. These substances go on concentrating at each trophic level of food chain, e.g., DDT and heavy metal (mercury, cadmium, etc.).

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  3. (i) Sewage; (ii) Industrial wastes; (iii) Synthetic soaps and detergents; (iv) Fertilizers and pesticides; (v) Petroleum; (vi) Heat.

    (i) Sewage; (ii) Industrial wastes; (iii) Synthetic soaps and detergents; (iv) Fertilizers and pesticides; (v) Petroleum; (vi) Heat.

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  4. Generally, tetraethyl lead is added to petrol to make it burn smoothly in motor vehicles. However, burning of petrol in automobiles releases toxic lead compounds through the exhaust pipes of automobiles. Continuous inhalation of these compounds causes anaemia, brain damage, convulsions and even deatRead more

    Generally, tetraethyl lead is added to petrol to make it burn smoothly in motor vehicles. However, burning of petrol in automobiles releases toxic lead compounds through the exhaust pipes of automobiles. Continuous inhalation of these compounds causes anaemia, brain damage, convulsions and even death.

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  5. This technique is used to capture and store rain water by making special water harvesting structures so that there is an increase in the recharge of underground water resources.

    This technique is used to capture and store rain water by making special water harvesting structures so that there is an increase in the recharge of underground water resources.

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