Explain the significance of clear-cutting, acid rain, smog, and eutrophication

CLEAR-CUTTING: CLEAR CUTTING IS THE REMOVAL OF ALL TREES IN ONE OPERATION FOR HARVESTNG PURPOSE. IT IS ECONOMICALLY PROFITABLE METHOD OF LOGGING. IT GIVES SIDE EFFECTS SUCH AS LOSS OF TOP SOIL. ACID RAIN : IT IS CAUSED BY EMISSIONS OF SULFUR-DI-OXIDE AND NITROGEN OXIDE WHICH REACT WITH WATER MOLECULES IN THE ATMOSPHERE TO PRODUCE ACIDS. SIGNIFICANCE OF ACID RAIN IS SENSITIVITY OF AGRICULTURAL LAND TO LONG-TERM ACID PRECIPITATION. SMOG : IT IS A MIXTURE OF SOLID AND LIQUID FOG. IT IS ALSO CALLED PHOTO CHEMICAL SMOG. FOG POLLUTED WITH SMOKE AND PARTICULATES ESPECIALLY FROM BURNING COAL. EUTROPHICATION : SEWAGE AND WASTE WATERS FROM INDUSTRIES AND AGRICULTURE ARE RICH IN ORGANIC AND INORGANIC NUTRIENTS CONTAINING PHOSPHOROUS AND NITROGEN TO SOME EXTENT.

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Answerdistinguish between the mercalli scale and the richter scale;