Carbon sequestration in living biomass of Slovak forests: recent trends and future projection

The paper predicts development of forests in Slovakia from the perspective of carbon sequestration. Projection is based on actual trends of changes in forest area, age structure and tree species composition of forest stands managed according to forest management plans. Carbon balance in living biomass has been simulated until 2050 under two harvesting scenarios (based on planned and realized harvesting rates in reference period 2014–2019) with four possible combinations of fixed or changing tree species composition and size of forest area. Input data were stratified by tree species and 10-years wide age classes. A model simulating forest growth using yield tables and harvesting rates was developed and applied for prediction. Results indicate that the scenario based on realized harvesting would lead to a higher level of CO₂ removals from atmosphere by living biomass in Slovak forests for the whole simulated period, despite their decrease from the current level ~ −4,000 kt CO₂ to ~ −2,000 until 2040 and an increase to~ −2,800 kt CO₂ in 2050. Conversely, scenario based on planned harvesting could result in a stronger decrease of CO₂ removals, with the culmination in 2040 at ~ −200 kt CO₂ followed by a slight increase to ~ −1,000 kt CO₂ in 2050. The influences of changes in tree species composition and increasing forest area were significantly lower than effect of different harvesting rates. Results achieved by this study suggest that adjusting harvested volume (e.g., by decreasing harvesting rates or modifying rotation periods) could be the most effective tool to intensify CO₂ removals by living biomass in Slovak forests in the upcoming decades.