1. During time, air over the land becomes heated up by sun rays, it rises up and creates area of low pressure. Water of lake is not heated-up by sun rays so quickly. Evaporation of water from its surface also cools up the lake water. So, air over the surface of lake is cooler. It moves towards the landRead more

    During time, air over the land becomes heated up by sun rays, it rises up and creates area of low pressure. Water of lake is not heated-up by sun rays so quickly. Evaporation of water from its surface also cools up the lake water. So, air over the surface of lake is cooler. It moves towards the land where low pressure exists. Therefore, during day time a cool breeze flows from lake to the near by

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  2. Water gets polluted from domestic wastes (loaded with detergents, faecal matter, etc.), fertilisers and pesticides from crop fields and industrial wastes (heavy metals, waste heat). (i) Fertilisers and domestic wastes cause eutrophication or increased organic loading and excessive growth of algae (aRead more

    Water gets polluted from domestic wastes (loaded with detergents, faecal matter, etc.), fertilisers and pesticides
    from crop fields and industrial wastes (heavy metals, waste heat).
    (i) Fertilisers and domestic wastes cause eutrophication or increased organic loading and excessive growth of algae (algal bloom). This ultimately reduces oxygen available to aquatic animals (fish, molluscs) and kill them.
    (ii) Domestic wastes also carry pathogens of a number of human diseases. Some of them can cause diseases of animals as well.
    (iii) Pesticides and pollutants of industrial wastes directly harm the aquatic organisms and humans.

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  3. Rivers are formed from melting snow springs, and rain water flowing over land as run off. while passing through and over the rocks, the flowing water picks up minerals, silt and sand. These dissolved and suspended substances are carried by rivers to sea and make them available to marine organisms.

    Rivers are formed from melting snow springs, and rain water flowing over land as run off. while passing through and over the rocks, the flowing water picks up minerals, silt and sand. These dissolved and suspended substances are carried by rivers to sea and make them available to marine organisms.

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  4. Earth's atmosphere is different from that of Venus and Mars. It contains only 0.03% carbon dioxide in addition to nitrogen, oxygen and water vapour. This is due to consistent presence of life on Earth (Gaia hypothesis). In comparison to Earth's atmosphere, atmosphere of Venus and Mars is rich in CO₂Read more

    Earth’s atmosphere is different from that of Venus and Mars. It contains only 0.03% carbon dioxide in addition to nitrogen, oxygen and water vapour. This is due to consistent presence of life on Earth (Gaia hypothesis). In comparison to Earth’s atmosphere, atmosphere of Venus and Mars is rich in CO₂ (having 95 to 97% CO₂) and lifeless.

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  5. (l) Burning of fossil fuels in vehicles, thermal plants and industries. (ii) Particulate and gaseous emissions from industries, mining, processing and stone crushing.

    (l) Burning of fossil fuels in vehicles, thermal plants and industries.
    (ii) Particulate and gaseous emissions from industries, mining, processing and stone crushing.

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