Are 40 years better than 55 ? An analysis of the reduction of forest rotation to face drought event in a Douglas fir stand.

- Context: Reduction of rotation length emerges as a potential adaptation strategy to cope with climate change. - Aim: To address the reduction of rotation length to deal with the drought-induced risk of forest decline taking a multidisciplinary approach.- Methods: We estimate probabilities and impacts of drought events quantified by water balance modelling and we evaluate, from an economic point of view, the reduction of rotation length to cope with the drought-induced risk of forest decline. We compare three different adaptation strategies at the economic level: absence of adaptation, immediate adaptation and delayed adaptation.- Results: Results suggest that immediate reduction of rotation length is associated with the best economic return, followed by delayed adaptation and, finally, by the absence of adaptation. This result is sensitive to the level of timber loss in the event of drought occurrence. If the loss of timber volume is higher than 48%, then delayed adaptation may be preferable to immediate adaptation. - Conclusion: Beyond the specificities of the case study, this paper proposes a multidisciplinary approach to address adaptation strategies