ABSTRACT
The emergence of sustainability as an important goal for agriculture and development has stimulated increasing interest in understanding ecological processes within agriculture so that they can be managed more effectively for enhancing agricultural productivity and reducing negative environmental impacts of agricultural activities. Although the opportunities created by agroecological approaches to agricultural development have been demonstrated many times, as seen in Part 2 of this volume, there is still much to be learned about how such approaches may actually function. Understanding the functioning of practices such as described in this volume will allow for better design of agricultural practices and systems that enhance both productivity and environmental benefits. Increasingly, these benefits are not only sought within countries but are sometimes imposed upon them, as when the maximum residue levels of pesticides tolerated in fruit, vegetables and flowers imported from tropical countries were dramatically decreased by the European Union in mid-2001.
