Agroecology is a scientific discipline that uses ecological theory to study, design, manage and evaluate agricultural systems that are productive but also resource conserving

This quote is taken from Agroecology in Action. A much more thorough definition of agroecology can be found on this site.

Agroecology moves beyond the technical aspects of agricultural production and considers the social, cultural, economics and environmental concerns facing agricultural systems and the people within them. We believe it is going to be a big part of future agriculture.

Links to further information on Agroecology.