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Forest soils represent a large carbon pool and already small changes in this pool may have an important effect on the global carbon cycle. To predict the future development of the soil organic carbon (SOC) pool, well-validated models are needed. We applied the litter and soil carbon model Yasso15 to 1838 plots of the German national forest soil inventory (NFSI) for the period between 1985 and 2014 to enables a direct comparison to the NFSI measurements. In addition, to provide data for the German Greenhouse Gas Inventory, we simulated the development of SOC with Yasso15 applying a climate projection based on the RCP8.5 scenario. The initial model-calculated SOC stocks were adjusted to the measured ones in the NFSI. On average, there were no significant differences between the simulated SOC changes (0.25 ± 0.10 Mg C ha−1 a−1) and the NFSI data (0.39 ± 0.11 Mg C ha−1 a−1). Comparing regional soil-unit-specific aggregates of the SOC changes, the correlation between both methods was significant (r2 = 0.49) although the NFSI values had a wider range and more negative values. In the majority of forest types, representing 75% of plots, both methods produced similar estimates of the SOC balance. Opposite trends were found in mountainous coniferous forests on acidic soils. These soils had lost carbon according to the NFSI (−0.89 ± 0.30 Mg C ha−1 a−1) whereas they had gained it according to Yasso15 (0.21 ± 0.10 Mg C ha−1 a−1). In oligotrophic pine forests, the NFSI indicated high SOC gains (1.36 ± 0.17 Mg C ha−1 a−1) and Yasso15 much smaller (0.29 ± 0.10 Mg C ha−1 a−1). According to our results, German forest soils are a large carbon sink. The application of the Yasso15 model supports the results of the NFSI. The sink strength differs between forest types possibly because of differences in organic matter stabilisation.

The objectives of this study were to examine the new hybrid technology chipper, Kesla C 860 H in comparison to two conventionally diesel-powered chippers, when chipping conifer pulpwood and logging residues. Productivity, fuel consumption and quality of the chips were measured and analyzed. During the time studies, both the chipper and hybrid system were working well. Chip quality was good and met the demands of small-scale residential boiler users. The average chipping productivity of the hybrid chipper unit was 13.1 oven dry metric tonnes (odt) per effective hour (E0h) when chipping logging residues and 11.3 odt E0h−1 when chipping pulpwood. This was lower than for the conventional chippers which produced 20.1 odt E0h−1 when chipping logging residues and 31.2 odt E0h−1 and 14.0 odt E0h−1 when chipping pulpwood. Fuel consumption of the hybrid chipper was 2.9 litres per odt for logging residues and 3.1 litres per odt when chipping conifer pulpwood, which was slightly lower than for the conventiona...

Three geometrical thinning methods were tested and compared with conventional selective thinning. The geometrical harvesting methods were two boom corridor (BCT1, BCT2) and one machine corridor (MCT) methods. In the BCT-methods all trees were removed from 1.5 m wide and 10 m deep corridors which were placed on both sides of the trip road at each operational stop. In BCT1, three corridors were made on both sides of the machine at various angles to the travel direction at each operational stop at 10 m intervals. In BCT2, corridors were made only at a 60° angle and 3 m intervals. In the MCT trees were removed only from the front of the machine. BCT2 had the highest productivity in harvesting, forwarding and overall productivity (3.96 m3/E0). The selective thinning was even in harvesting but lower in forwarding and overall productivities (3.82 m3/E0). BCT1 productivity was lower in harvesting and forwarding with 3.68 m3/E0 overall productivity. In the MCT the dense treetops in front of the machine oft...

Digital maps of forest resources are a crucial factor in successful forestry applications. Since manual measurement of this data on large areas is infeasible, maps must be constructed using a sampl...

Human-induced fragmentation affects forest continuity, i.e. availability of a suitable habitat for the target species over a time period. The dependence of wood-inhabiting fungi on landscape level continuity has been well demonstrated, but the importance of local continuity has remained controversial. In this study, we explored the effects of local forest continuity (microhabitat and stand level) on the diversity of wood-inhabiting fungi on standing dead trunks of Scots pine (Pinus sylvestris L.). We studied species richness and community composition of decomposers and Micarea lichens on 70 trunks in 14 forests in central Finland that differed in their state of continuity. We used dendrochronological methods to assess the detailed history of each study trunk, i.e. the microhabitat continuity. The stand continuity was estimated as dead wood diversity and past management intensity (number of stumps). We recorded 107 species (91 decomposers, 16 Micarea lichens), with a total of 510 occurrences. Using generalized linear mixed models, we found that none of the variables explained decomposer species richness, but that Micarea species richness was positively dependent on the time since tree death. Dead wood diversity was the most important variable determining the composition of decomposer communities. For Micarea lichens, the community composition was best explained by the combined effect of years from death, site and dead wood diversity. However, these effects were rather tentative. The results are in line with those of previous studies suggesting the restricted significance of local forest continuity for wood-inhabiting fungi. However, standing dead pines that have been available continuously over long periods seem to be important for species-rich communities of Micarea lichens. Rare specialists (e.g. on veteran trees) may be more sensitive to local continuity, and should be at the center of future research. peerReviewed

Sequestering carbon in forests and wood products is an inexpensive way to reduce the atmospheric carbon concentration. However, its full potential is not utilized in present climate policies. Optimizing sequestration, while continuing to harvest wood for materials and energy, could reduce the economic burden of mitigation efforts. Optimal sequestration can be incentivized by subsidizing carbon storage according to its social value. We analyze the dynamic market-level impacts of implementing a forest carbon policy by using the Finnish Forest and Energy Policy model (FinFEP). We find that sizeable and immediate increases in carbon sinks can be obtained, even with low carbon prices. High carbon payments strongly increase the carbon sink in the short run, but this impact diminishes over time. Low payments have a milder but longer-lasting impact. Forest owners’ valuations of forest amenities also affect the magnitude and dynamics of harvest and carbon sequestration results. Thus, a realistic description of forest owner behavior is needed to assess the impacts of forest carbon policies. Moreover, we show that a market-level model is necessary for assessing the regional carbon sequestration impacts and costs. Relying on stand-level models with fixed timber prices may yield overly optimistic results.

Forests play a crucial role in the transition towards a bioeconomy by providing biomass to substitute for fossil-based materials and energy. However, a policy-policy conflict exists between the desire to increase the utilization of bio based renewable resources and the desire to protect and conserve biodiversity. Increasing forest harvest levels to meet the needs of the bioeconomy may conflict with biodiversity protection and ecosystem services provided by forests. Through an optimization framework, we examined trade-offs between increasing the extraction of timber resources, and the impacts on biodiversity and non-wood ecosystem services, and investigated possibilities to reconcile trade-off with changes in forest management in 17 landscapes in boreal forests. A diverse range of alternative forest management regimes were used. The alternatives varied from set aside to continuous cover forestry and a range of management options to reflect potential applications of the current management recommendations. These included adjustments to the number of thinning, the timing of final felling and the method of regeneration. Increasing forest harvest level to the maximum economically sustainable harvest had a negative effect on the habitat suitability index, bilberry yield, deadwood diversity and carbon storage. It resulted in a loss in variation among landscapes in their conservation capacity and the ability to provide ecosystem services. Multi-objective optimization results showed that combining different forest management regimes alleviated the negative effects of increasing harvest levels to biodiversity and non-wood ecosystem services. The results indicate that careful landscape level forest management planning is crucial to minimize the ecological costs of increasing harvest levels.

In this paper we address the disconnection between multifunctional woodland management and current forestry policies in Europe, using a practice theory approach. Drawing on cases in the UK and Finland, we identified seven bundles forestry practices: creating an attractive place to live, pursuing forest-based leisure practices, wildlife and biodiversity preservation, heritage conservation, renewable heat production, animal husbandry and timber production. By assessing the place of these forest-based practices within larger practice ‘complexes’ (such as farming, urban employment, family recreation), we demonstrate disconnections to current incentive programmes, which are largely oriented towards professional farmers or foresters. We found that study participants were largely unopposed to achieving national policy objectives (afforestation in the UK and commercial timber production in Finland); instead, their limited active engagement reflected available competencies and the lack of resources (particularly time) available to non-commercial forest managers. We argue that using practice theory helps to identify new opportunities to influence existing practices, such as increasing competences in harvesting of continuous growth forestry in Finland and encouraging small-scale renewable heat production in the UK.

Soil rutting caused by forest operations has negative economic and ecological effects and thus limits for rutting are set by forest laws and sustainability criteria. Extensive data on rut depths are necessary for post-harvest quality control and development of models that link environmental conditions to rut formation. This study explored the use of a Light Detection and Ranging (LiDAR) sensor mounted on a forest harvester and forwarder to measure rut depths in real harvesting conditions in Southern Finland. LiDAR-derived rut depths were compared to manually measured rut depths. The results showed that at 10–20 m spatial resolution, the LiDAR method can provide unbiased estimates of rut depth with root mean square error (RMSE) < 3.5 cm compared to the manual rut depth measurements. The results suggest that a LiDAR sensor mounted on a forest vehicle can in future provide a viable method for the large-scale collection of rut depth data as part of normal forestry operations.

Generalist species are usually widespread and abundant, and thrive in heterogeneous environments. Specialists, in turn, are generally more restricted in their range, and benefit from more stable conditions. Therefore, increasing human-induced disturbance can have more negative effects on specialist than generalist species. We assessed the specialization of 77 wood-inhabiting fungal species across seven boreal forest types and different substratum qualities. A significantly higher number of specialist species was associated with herb-rich forests and afforested fields than with managed coniferous forests and wood pastures, the number of specialists associated with natural coniferous forests being intermediate. Also, forest type specialists were indicated to be specialists for their substratum tree species as well, but specialization in substratum diameter was not connected with other kinds of specialization. Species with restricted resource or habitat preferences can less readily respond to environmental change, and therefore are more vulnerable to extinction. peerReviewed

We developed a temperature sum model to predict the daily pollen release of alder, based on pollen data collected with pollen traps at seven locations in Finland over the years 2000–2014. We estimated the model parameters by minimizing the sum of squared errors (SSE) of the model, with weights that put more weight on binary recognition of daily presence or absence of pollen. The model results suggest that alder pollen ripens after a couple of warm days in February, while the whole pollen release period typically takes up to 4 weeks. We tested the model residuals against air humidity, precipitation and wind speed, but adding these meteorological features did not improve the model prediction capacity. Our model was able to predict the onset of pollen season with similar accuracy as models describing only the start of the pollen release period (average prediction error 8.3, median 5.0 days), while for the end of the pollen release period the accuracy of our predictions was not as good. We split the pollen data into odd and even years, and fitted our model separately to each half. Difference in the parameter values suggests a biennial behavior in the onset of pollen ripening, with almost two weeks of difference in the modeled starting date of the pollen development. Monte Carlo resampling of the observation data confirmed that the difference is not just a random anomaly in the data.

In the present study, durability of untreated and thermally modified sapwood and heartwood of Scots pine and Norway spruce was examined using a modified double layer test. Base layer samples were partly on contact with ground where exposure conditions were harder than that in a double layer test above the ground. The base layer on ground contact gave results already after one year of exposure in Finnish climate, but the top layer of a double layer test element simulated more the situation of decking exposure. Significant differences in durability and moisture content (MC) between the wood materials were detected after six years of exposure in the field. Thermally modified pine heartwood performed very well in all layers of the test element and only minor signs of decay were found in some of the base samples. Both sapwood and heartwood of thermally modified spruce were suffering only slight amounts of decay while thermally modified pine sapwood was slightly or moderately decayed. Untreated sapwood samples of pine and spruce were severely decayed or reached failure rating after six years in the field. Untreated heartwood samples performed clearly better. The highest MCs were measured from untreated and thermally modified pine samples. Thermal modification increased significantly the durability and decreased the MC values of all wood materials.

The ability to facilitate superior customer value creation is critical for firms’ long-term success. The topic has been studied extensively in marketing literature, but less consideration has been given to customer orientation and customer value creation in the forestry context. Through 18 qualitative interviews with suppliers and customers in the Finnish sawn timber value chain, sawmills’ customer orientation was analyzed. We find that the concept of customer orientation was realized rather narrowly at sawmills and customer orientation appeared as random actions instead of a systematic part of firms’ organization culture. Customers’ needs are more manifold and extend beyond product characteristics and process efficiency. The main challenge hindering the renewal of product-oriented business models toward service logic and customer orientation seems to be in attitudes and traditions.