1. (i) Intensive cropping and reforestation; (ii) Terrace farming.

    (i) Intensive cropping and reforestation; (ii) Terrace farming.

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  2. Humus is partially decayed organic matter. It makes soil porous, thereby increasing its air and water holding capacity. It is rich in nutrients (e.g., minerals) that promote plant growth. Being black or dark brown in colour, humus absorbs heat to warm up the soil.

    Humus is partially decayed organic matter. It makes soil porous, thereby increasing its air and water holding capacity. It is rich in nutrients (e.g., minerals) that promote plant growth. Being black or dark brown in colour, humus absorbs heat to warm up the soil.

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  3. The whole process of weathering of rocks involving living organisms is called biological weathering, e.g., Lichens, mosses, herbs, shrubs and trees.

    The whole process of weathering of rocks involving living organisms is called biological weathering, e.g., Lichens, mosses, herbs, shrubs and trees.

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  4. The phenomenon of increase in the concentration of harmful non-biodegradable substances in the body of living organisms at each trophic level of the food chain is called bio magnification. Two heavy metals which are biomagnified are mercury and cadmium.

    The phenomenon of increase in the concentration of harmful non-biodegradable substances in the body of living organisms at each trophic level of the food chain is called bio magnification. Two heavy metals which are biomagnified are mercury and cadmium.

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  5. 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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