1. Lichens release small quantity of acids which corrode the surface of rock creating minute pores and releasing minerals. With the passage of time these minerals deposit on rock to form a thin layer of soil.

    Lichens release small quantity of acids which corrode the surface of rock creating minute pores and releasing minerals. With the passage of time these minerals deposit on rock to form a thin layer of soil.

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  2. In a pond, a mass mortality of fish may occur due to following seasons. (i) Passage of pesticide rich water from crop fields. (ii) Release of toxic industrial waste. (iii) Pouring of hot water from an industry or thermal power plant. (iv) Release of waste rich in heavy metals and mercury. (v) BlockaRead more

    In a pond, a mass mortality of fish may occur due to following seasons.
    (i) Passage of pesticide rich water from crop fields.
    (ii) Release of toxic industrial waste.
    (iii) Pouring of hot water from an industry or thermal power plant.
    (iv) Release of waste rich in heavy metals and mercury.
    (v) Blockage of gills of fish by some suspended pollutant such as oil.

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  3. Salt water of seas and oceans is unfit for consumption by humans, animals, land plants or industries. Therefore, terrestrial biota and human beings have to depend upon fresh-water resources available on land (such as water present in rain snow, springs, river, lakes, ponds and other freshwater bodieRead more

    Salt water of seas and oceans is unfit for consumption by humans, animals, land plants or industries. Therefore, terrestrial biota and human beings have to depend upon fresh-water resources available on land (such as water present in rain snow, springs, river, lakes, ponds and other freshwater bodies (only about 0.5% of the total water on earth). As a result, freshwater needs its conservation

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  4. Lichens act as indicators of air pollution. They are sensitive to sulphur dioxide which occurs in sufficient quantity in the atmosphere of Delhi due to large number of vehicles, homes and factories using fossil fuels., Also Delhi exists in semiarid area where atmospheric moisture is low. In Manali aRead more

    Lichens act as indicators of air pollution. They are sensitive to sulphur dioxide which occurs in sufficient quantity in the atmosphere of Delhi due to large number of vehicles, homes and factories using fossil fuels., Also Delhi exists in semiarid area where atmospheric moisture is low. In Manali and Darjeeling, the atmosphere is humid and has comparatively low contents of sulphur dioxide.

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  5. Mathura refinery emits hydrocarbons and sulphur oxides in its exhaust/fumes. Hydrocarbons induce the formation of ozone which is highly oxidizing. Sulphur dioxide produces acid rain which has a corroding effect on marble. As a result, Mathura refinery does pose problems to Taj Mahal.

    Mathura refinery emits hydrocarbons and sulphur oxides in its exhaust/fumes. Hydrocarbons induce the formation of ozone which is highly oxidizing. Sulphur dioxide produces acid rain which has a corroding effect on marble. As a result, Mathura refinery does pose problems to Taj Mahal.

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