Vincent de Leijster

143 Synthesis and conclusion 7 farms with a dispersed tree arrangement, the coffee yields were lower than in monoculture farms, but there were no differences in farms with alley or living fence tree arrangements. Agroforestry farms obtained 30% of the total value of timber, fruit and carbon in the form of actual revenue, while the other 70% was not brought to market. The non-marketed share of products was either consumed on the farm, given to labor workers or wasted. The potential revenue of non-marketed products was highest for farms with a dispersed tree arrangement. Finally, we found that economic performance was best explained by pest control intensity, altitude, farm size and vendor choice, and that canopy characteristics were significantly less important. We concluded that agroforestry can and should be implemented in Colombian coffee systems, since net revenues are not negatively affected by the small decreases in coffee yield. There is a large untapped potential for further improvement of the actual revenues of agroforestry farms by better marketing of timber, fruit and carbon. 7.2 Discussion The ecological and economic impacts of various agroecological interventions were addressed in two case studies. The results of these studies provide us with the information needed to address the aim of the thesis and its specific sub-questions that were presented in the introduction in Section 1.5. Importantly, because of the great differences in their biophysical contexts (dryland versus tropics), the case studies are used to compare specific ecological and economic developments, but rather two examples that give information about how agroecological interventions, farming strategies, and incentives inter-relate. RQ 1: How does ecological performance differ between conventional and agroecological systems? In Chapters 3 and 5 we tested the difference in ecological performance between conventional and agroecological almond and coffee systems. We measured indicators for ecosystem services to obtain information about the ecological performance. In Chapter 3 we concluded that the accumulated ecosystem service provisioning was 17-28% higher for each of the agroecological treatments, i.e. compost, no tillage and green manure, than for the conventional tillage treatment. Compost improved nutrient cycling processes in comparison to conventional tillage and no tillage, and green manure improved plant diversity, soil microbial activity, and understory carbon stock. Therefore, we conclude that the ecological performance of agroecologically managed almond orchards is higher than those of almond orchards with conventional tillage. In Chapter 5 we concluded that some ecosystem services