Operationalising ecosystem service assessment in Bayesian Belief Networks: Experiences within the OpenNESS project

•BBNs modelled ecosystem services for 9 different case study applications.•BBNs are flexible, transparent, and useful for participatory stakeholder work.•BBNs recognise socio-ecological uncertainty and stakeholders welcomed this.•Spatial BBN/GIS is a useful tool, but correct uncertainty estimation is vital.•Web interfaces helped promote interactive stakeholder participation.