Introduction

The impact of human beings on our planet has been so extended and amplified by technology that our presence as a species can no longer be considered part of natural evolutionary ecological processes. What is more, our impact on the planet fundamentally threatens our own environmental security (Colborn et al., 1996; Lubchenco, 1998; McMichael, 1995, Pimentel, 1996). Natural processes supporting the existence of various ecosystems and the diversity within and among ecosystems, which is a prerequisite for their resilience, are now at risk.