Throughout history man has changed his physical environment in order toimprove his way of life. With the tools of technology he has altered manyphysical features of the earth. He has transformed woodlands and prairies intofarms and made lakes and reserviors out of rivers for irrigation purposes orhydroelectric power. Man has also modified the face of the earth by drainingmarshes and cutting through mountains to build roads and railways.
However, man's changes to the physical environment have not always hadbeneficial results. Today, pollution of the air and water is an increasingdanger to the health of the planet. Each day thousands of tons of gases come outof the exhausts of motor vehicles. Smoke from factories pollutes the air ofindustrialized areas and the surrounding areas of the countryside. The pollutionof water is equally harmful. The whole ecological balance of the sea is beingchanged and industrial wastes have already made many rivers lifeless.
Now environmental protection is more pressing than ever before. As we know,massive destruction of environment has brought about negative effects and evenposes a great threat to man's existence. Indifference to these problems willmean committing suicide. Therefore, effective measures should be taken and lawspassed to conserve environment. Otherwise,man is certain to suffer from theserious consequences caused by this lack of care for his livingsurroundings.
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