Contribution of agroecological farming systems to the delivery of ecosystem services.

Agroecology has been suggested as a promising concept for reconciling agricultural production and environmental sustainability by optimizing ecological processes that deliver ecosystem services (ES) to replace external inputs. While this statement is widely agreed upon, few assessments of real-life conditions exist that assess multiple ES simultaneously. This paper provides an assessment of seven ES based on 14 indicators in three agroecological farming systems (AFS) and thirteen of their adjacent conventional farming systems (CFS). Based on field-scale measurements spread over three years, our findings suggest that the studied AFS succeed in providing a wider array of regulating services than their neighboring CFS. Soil aggregate stability and soil respiration rates are in general more supported in AFS, which also show lower pest abundance. On the other hand, CFS show higher grain production and higher performance for two out of three fodder quality indices. While this 'productivity gap' may be due to the still-evolving state of the studied AFS, we nuance this through the lens of an emerging paradigm to assess farming system multi-performance. It is now argued that we need to shift from a volume-focused production system to a system that also values the ecological processes underpinning crop production and other benefits to society. Based on our findings, we recommend future work to iterate our initiative, including several indicators per service and embed these into a wider context of co-adaptive science-practice to further develop context-specific and user-useful research.

Spatial diversification of agroecosystems to enhance biological control and other regulating services: An agroecological perspective.

Spatial diversification of crop and non-crop habitats in farming systems is promising for enhancing natural regulation of insect pests. Nevertheless, results from recent syntheses show variable effects. One explanation is that the abundance and diversity of pests and natural enemies are affected by the composition, design and management of crop and non-crop habitats. Moreover, interactions between both local and landscape elements and practices carried out at different spatial scales may affect the regulation of insect pests. Hence, research is being conducted to understand these interdependencies. However, insects are not the only pests and pests are not the only elements to regulate in agroecosystems. Broadening the scope could allow addressing multiple issues simultaneously, but also solving them together by enhancing synergies. Indeed, spatial diversification of crop and non-crop habitats can allow addressing the issues of weeds and pathogens, along with being beneficial to several other regulating services like pollination, soil conservation and nutrient cycling. Although calls rise to develop multifunctional landscapes that optimize the delivery of multiple ecosystem services, it still represents a scientific challenge today. Enhancing interdisciplinarity in research institutions and building interrelations between scientists and stakeholders may help reach this goal. Despite obstacles, positive results from research based on such innovative approaches are encouraging for engaging science in this path. Hence, the aim of the present paper is to offer an update on these issues by exploring the most recent findings and discussing these results to highlight needs for future research.