Biological and Ecological Dimensions of Global Environmental Change

Humans have populated the Earth for thousands of years but not until the last few centuries have they played a major role in influencing the structure and metabolism of the global biosphere. Human-induced changes have today reached such an extent that, in some cases, they are as important or even more important than those caused by the geological and climatic forces that shaped the Earth’s environment over the previous thousands of years. There is no doubt that the growth of human popula-tions and associated resource consumption have been the major drivers behind the large biospheric transformations that have occurred, particularly in the last few decades. Both the total and the per capita exploitation of the Earth’s resources have been nearly exponential for some time now. The human population has increased tenfold to 6 billio