Estimation of the Overmature Wood Stock and the Projection of the Maximum Wood Mobilization Potential up to 2100 in Hungary

Abstract

The demand for woody biomass as a key raw material of the developing circular bioeconomy is expected to increase. This has led to the need of increased timber productivity and the search for new procurement methods, new assortments, and innovative supply chains. Timber is regarded as a climate-friendly resource, which can contribute to climate change mitigation through long-term carbon storage and through the substitution of fossil products and fossil fuels. Thus, it is of high importance to assess the amount of timber that can be harvested without compromising sustainability concerns. In this paper, we examined the amount of the wood stock accumulated in overmature stands in Hungary. We define overmature stands being those stands where the actual age of the stand is over its cutting age prescribed by the forest authority. According to our results, 11.5% of the standing volume in Hungary is overmature, and the wood stock of overmature stands has increased by more than 250% in the last 40 years. The importance of the overmature forests is enormous, as they represent an unused wood stock reserve, which could be available to meet the growing demand for timber. In our study, we also conducted a simple yield table-based projection on the maximum amount of timber available for harvest in the period 2020–2100 based on the data of the national forestry database and the cutting ages prescribed by the forest authority in the forest management plans. According to our results, even without new afforestation, more timber becomes available for harvest annually in the 2020–2100 period than the level of the average harvests of the last five historic years. In the 2020–2050 period, an additional 56% of timber is projected to become available for harvest as a maximum. This means a maximum additional potential of 4059 thousand m3, even without the harvesting of the stands, which were already overmature in the starting year of the projection. In the first part of the projection period, industrial wood available for harvest is forecasted to be above the average historic level of industrial wood production. However, in the second part of the projection period, the industrial wood yield shows a decreasing tendency and even drops below the 2017–2021 average. The decreasing availability of industrial roundwood in the second part of the projection period points out the importance of innovation in the wood industry. The inclusion of drought tolerant species, which are nowadays less used for industrial purposes seems inevitable in the production of high-quality wood products.