An enhancement of ecosystem resilience (ER, the ability to retain structure and functioning after disturbance), is necessary to sustain ecosystem services and biodiversity through environmental fluctuations imposed by the ongoing climate change. To achieve this goal, we need to deepen our understanding of functional mechanisms of ER. In the proposed project we explore climatic ER of fen mires, ecosystems which play a key-role in the conservation of European biodiversity and provide vital regulatory services. Natural mires are characterised by high ER and remain stable unless environmental changes pass thresholds, which may turn them into alternative stable states (less desirable for conservation). To understand mechanisms of mire ER, we adopt a multidisciplinary and multiple temporal-scale approach, integrated with the use of functional diversity (FD) and functional trait spectra as predictors of ecosystem functioning and resilience to climate change. Information on fen responses to climatic and hydrological fluctuations will be derived from (1) long-term studies of vegetation, (2) comparisons between boreal (Norway) and temperate (Poland) systems and (3) medium to short-term responses of fens to management and restoration, based on on-going research in several areas. The impact of management on ecosystem resilience will be studied in the Biebrza and Rospuda fens (NE Poland) and Sølendet and Tågdalen nature reserves in Norway. Ordination models developed on these datasets will be validated against palaeoecological data obtained by a meta-analysis and then used o build a predictive model, in which climate scenarios will be translated into localised hydrological models. Predictive modelling using FD response mechanisms of plant communities to various interacting ecological processes will be applied to propose adaptation scenarios for mires, with special case study of the Biebrza Valley.