Introducing territorial and historical contexts and critical thresholds in the analysis of conservation of agro-biodiversity by Alternative Food Networks, in Tuscany, Italy

•Review of literature on AFNs and related environmental impact assessments.•Identification of critical aspects for the assessment of AFNs’ impacts on agro-biodiversity conservation.•Analysis of the role played by AFNs in two case studies in Tuscany, Italy.•Consideration of the suitability and usefulness of the approach proposed to assess the contribution of AFNs to agro-biodiversity conservation.