**5. Future steps**

The next phase involves parametrising the chosen simulator using data from Switzerland and then checking its validity, that is, how accurately it reflects reality [36]. During the parametr‐ isation process, the simulator's key sub‐models, such as diameter and height increment, mortality and ingrowth, will be described climate‐sensitively and optimally adapted to the available data using appropriate functions. Consequently, it only makes sense to validate the simulator results once the reparametrisation has taken place. Furthermore, the individual‐tree simulators in question consist of multiple sub‐models. Pre‐validating the sub‐models would be highly resource intensive and not justified for the purposes at hand.

At a later stage, the chosen simulator will be integrated into an overarching DSS covering forest planning and management processes.

DSSs are crucial because the management of a forest is a challenging task as all the major ecosystem services, such as timber production, recreation, biodiversity conservation and carbon storage, occur side by side on a small scale and are highly demanded by society. Wrong management decisions can have huge consequences, ranging from a loss of ecological and social values up to a loss of economic income. This situation underlines the urgent need for appropriate concepts and tools for decision support that consider all ecosystemservices and can help forest managers to find an optimal management strategy to fulfil the diverse societal and political demanded services [3]. Climate change additionally exacerbates the problems [37].

For decision support systems, it is vital that the forest growth simulator links and interacts with multi‐criteria decision analysis (MCDA) [3, 38, 39]. Only the combined use of simulators and MCDA will cover all the phases involved in the forest‐planning process. This includes recognising a decision‐making problem, developing management alternatives and, ultimately, selecting an alternative and authorisation to implement it [39].
