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When this century began, neither human beings nor technology had the power radically to alter planetary systems. As the century draws to a close, not only do vastly increased human populations and their activities possess that power, but we are also faced with major unintended changes that are occurring in the atmosphere, in soil, in water, among plants and animals, and in the relationships among all of them.
Gro Harlem Brundtland (Thu,) studied this question.