Climate change impacts on a pine stand in Central Siberia

The objective of this paper is to analyse the impacts of climate change on a pine forest stand in Central Siberia (Zotino) to assess benefits and risks for such forests in the future. We use the regional statistical climate model STARS to develop a set of climate change scenarios assuming a temperature increase by mid-century of 1, 2, 3 and 4 K. The process-based forest growth model 4C is applied to a 200-year-old pine forest to analyse impacts on carbon and water balance as well as the risk of fire under these climate change scenarios. The climate scenarios indicate precipitation increases mainly during winter and decreases during summer with increasing temperature trend. They cause rising forest productivity up to about 20 % in spite of increasing respiration losses. At the same time, the water-use efficiency increases slightly from 2.0 g C l^?1 H₂O under current climate to 2.1 g C l^?1 H₂O under 4 K scenario indicating that higher water losses from increasing evapotranspiration do not appear to lead to water limitations for the productivity at this site. The simulated actual evaporation increases by up to 32 %, but the climatic water balance decreases by up to 20 % with increasing temperature trend. In contrast, the risk of fire indicated by the Nesterov index clearly increases. Our analysis confirms increasing productivity of the boreal pine stand but also highlights increasing drought stress and risks from abiotic disturbances which could cancel out productivity gains.