Projecting Climate Change Potential of Harvested Wood Products under Different Scenarios of Wood Production and Utilization: Study of Slovakia

The forestry and forest-based sector play a significant role in climate change mitigation strategies and can contribute to the achievement of a climate-neutral economy. In this context, the ability of harvested wood products (HWP) to sequester carbon is of significant importance. The objective of this work is to make a projection of climate change mitigation potential of HWP, under different scenarios of wood utilization in Slovakia. This study builds on the comparison of different scenarios of industrial wood utilization till 2035 and presents the resulting impacts on the national carbon balance. The results suggest that the development of timber supplies after 2020 in Slovakia will be influenced, in particular, by the future changes in the age distribution and tree species composition as well as the extent of future accidental felling. Consequently, a predicted structure and availability of wood resources in Slovakia will be reflected in a higher share of the production of products with shorter life cycle and thus will negatively affect the carbon pool in HWP. By comparing the results of the four designed scenarios, it follows that the scenario with the greatest mitigation potential, is the one assuming the optimal use of wood assortments and limitation of industrial roundwood foreign trade

Different Responses in Vascular Traits between Dutch Elm Hybrids with a Contrasting Tolerance to Dutch Elm Disease

The ascomycetous fungus Ophiostoma novo-ulmi is the causative agent of the current Dutch elm disease (DED) pandemic, which has ravaged many tens of millions of European and North American elm trees. Host responses in vascular traits were studied in two Dutch elm hybrids, ‘Groeneveld’ and ‘Dodoens’, which show different vascular architecture in the secondary xylem and possess contrasting tolerances to DED. ‘Groeneveld’ trees, sensitive to DED, possessed a high number of small earlywood vessels. However, these trees showed a poor response to DED infection for the earlywood vascular characteristics. Following infection, the proportion of least vessels with a vessel lumen area less than 2500 µm2 decreased from 65.4% down to 53.2%. A delayed response in the increasing density of vessels showing a reduced size in the latewood prevented neither the rapid fungal spread nor the massive colonisation of the secondary xylem tissues resulting in the death of the infected trees. ‘Dodoens’ trees, tolerant to DED, possessed a low number of large earlywood vessels and showed a prominent and fast response to DED infection. Vessel lumen areas of newly formed earlywood vessels were severely reduced together with the vessel size : number ratio. Following infection, the proportion of least vessels with a vessel lumen area less than 2500 µm2 increased from 75.6% up to 92.9%. A trend in the increasing density of vessels showing a reduced size was maintained not only in the latewood that was formed in the year of infection but also in the earlywood that was formed in the consecutive year. The occurrence of fungal hyphae in the earlywood vessels that were formed a year following the infection was severely restricted, as revealed by X-ray micro-computed tomography imaging. Possible reasons responsible for a contrasting survival of ‘Groeneveld’ and ‘Dodoens’ trees are discussed

Changes in Carbon Balance of Harvested Wood Products Resulting from Different Wood Utilization Scenarios

The bioeconomy focuses on the production of renewable biological resources and the utilisation of these resources and waste streams into value added products. One of the most important aims of the forest industry is the sustainable production of wood. Improved utilization of available industrial wood assortments generates profit for all in the supply chain. At the same time, it may ensure the production of long-life harvested wood products (HWP), and consequently, increase the volume of carbon stored. The objective of this study is to compare different scenarios of industrial wood utilization in Slovakia and the resulting impacts on the national carbon balance. In the proposed scenarios, we aimed to evaluate changes in the current utilization of domestic wood resources through optimizing harvested wood assortments. Two inventory stock methods were applied to determine the potential quality of domestic wood and its utilization through appropriate distribution of outputs. The model scenario assumes that the higher share of industrial roundwood utilised to produce long-life HWP (sawnwood, wood-based panels) will increase carbon sequestration in HWP. Other scenarios quantify the differences between the carbon volumes stored in HWP using the modelled wood assortment supplemented with alternatives with and without export. The results confirmed that increasing the level of carbon stored in HWP can be achieved by changing the wood assortment structure, while maintaining the same level of volume felled. The highest level of carbon stock was observed in the scenario assuming the optimal structure of wood assortments and no wood export. The scenario that optimized wood assortments and excluded wood exports resulted in the highest level of predicted carbon stock, estimated at 4.87 million tons (mil. tons)