Co-design and establishment of innovative fruit-based agroforestry cropping systems in Belgium

Multiple options exist to set up agroforestry systems that combine pome fruit trees and vegetables. Proposals for different spatial arrangements and prototypes have been developed and evaluated through participative discussions involving scientists, advisors and farmers. Key challenges will be to optimize economic/technical constraints and ecological principles that stimulate natural regulation processes against pests and diseases in a temperate climate. In 2014, an experimental agroforestry orchard was planted in Gembloux, Belgium, on a surface of one hectare. The aim was to test the following three hypotheses: (i) a mixture of selected robust fruit and vegetable cultivars creates a functional biodiversity that significantly reduces the risk of pests and diseases; (ii) annual crops and tree canopies may have an impact on soil functioning, biological interactions and regulations; and (iii) in our optimized ratio and distances between vegetables and trees in intensified and organized alley-cropping systems, the tree shading does not reduce light levels below the threshold of light saturation. Two other on-farm fruit-based agroforestry cropping prototypes in Belgium are under evaluation on two pilot farms according to the farmerRSQUOs production objectives, including: (i) adaptation to mechanization, which may limit plant interactions with perennial and/or annual crops; and (ii) the need for a diversified income per surface unit that would allow the economic viability of farms in a capital-intensive economic system.