An agronomic approach to yield comparisons between conventional and organic cropping systems

摘要

This paper discusses some relevant agronomic aspects related to the productivity of organic farming systems (OFS). In a first step some key requirements to ensure the validity of comparative studies including the consideration of rotation yields and the use of representative amounts of organic inputs are defined. A main chapter is dedicated to the potential of biological nitrogen fixation to substitute mineral nitrogen, which currently covers an estimated third of the total nitrogen input to agricultural field with increasing tendency. To bring forward OA as a sustainable method of food production with high process quality, it is suggested to focus rather on a large scale organic vegetable and fruit production than on global supply of calories and protein.