What does "kbA" mean

About Organic cultivation
(German: controlled biological cultivation) Organic cultivation is based on holistic thinking, agriculture/farming is seen as an organism and as an interaction between soil, plant, animal and the human being. Ecological associations such as DEMETER, Nature & Progres and many more focus on the rules of the worldwide association IFOAM (International Federation of Organic Agricultural Movement), and have laid down a multitude of guidelines that apply to organic cultivation:
Choice of plants appropriate to the site
Non-irrigated, little or only organically fertilized herb plantations
Crop rotation
Ban on herbicides
Biological pest control
Increase in the natural soil fertility, e.g. through composting
Ban on genetically manipulated seeds
No use of chemical-synthetic hormones, protective substances for storage or after ripening substances