Mountain grassland ecosystems are particularly vulnerable to direct climate impacts and to indirect climate change impacts through farmers' management adaptation. We modelled expected spatio-temporal trajectories of land management of a mountain grassland landscape in the French Alps under a range of short-term climate and socio-economic scenarios which were constructed using an advanced participatory approach with a variety of stakeholders. First, regional experts from nature conservation and agricultural extension were involved in the co-development of detailed qualitative climate and socioeconomic scenarios, expressed as coherent storylines. Second, to map land management adaptation to these storylines, we used a role playing game whereby farmers were put in an imaginary future situation and asked to make decisions under scenario constraints. For each scenario, game outcomes were used to map future land management at parcels to landscape scales. Main adaptations were conversion from mowing to grazing and increasing manured area, with varying proportions and locations for these two types of changes differing across scenarios, though overall small. These results highlight the limited adaptability of current farmers given a strongly constraining natural and social context. Beyond research outputs, this framework generated interesting outcomes for stakeholders and raised their awareness about the socio-ecological system's vulnerability to future changes.