Figure - available from: European Journal of Forest Research
This content is subject to copyright. Terms and conditions apply.
Source publication
We studied how the use of certain tree species in forest regeneration affected the volume growth, timber yield, and carbon stock of boreal forests in Finland under the current climate (1981–2010) and recent-generation global climate model (GCM) predictions (i.e., multi-model means and individual GCMs of CMIP5), using the representative concentratio...
Similar publications
We studied how the use of certain tree species in forest regeneration affected the regional wind damage risks to Finnish boreal forests under the current climate (1981–2010) and recent-generation global climate model (GCM) predictions (i.e., 10 GCMs of CMIP5, with wide variations in temperature and precipitation), using the representative concentra...
Citations
... Climate change and the related increases in natural disturbances affect the functioning of forests and consequently the provisioning of different ecosystem services (Gauthier et al. 2015;Seidl et al. 2014;Reyer et al. 2017;Venäläinen et al. 2020). However, forest management has a greater impact on ecosystem services than gradual climate change (Alrahahleh et al. 2016(Alrahahleh et al. , 2018a(Alrahahleh et al. , 2018bTriviño et al. 2023). This is although forest growth and carbon sequestration are mostly expected to increase under climate change in boreal conditions (Kellomäki et al. 2008;Poudel et al. 2011Poudel et al. , 2012Kellomäki et al. 2018). ...
... In practice, the management recommendations are not strictly followed and there exist harvest savings in the forests. To avoid harvesting of all harvest savings in the first years of simulations, we used a mean delay of 13 years in the thinning and final felling as was done in previous simulation studies by Alrahahleh et al. (2016Alrahahleh et al. ( , 2018a. The lack of initial amount of dead wood in forest inventory data affected the simulated amount of dead wood and further habitat suitability area over time. ...
... In previous simulation studies, use of more severe RCP-scenarios (e.g. RCP8.5 by 2100) were found to reduce the volume growth of forests due to increase in tree mortality, as growing conditions become suboptimal for conifer species, especially in southern Finland (Alrahahleh et al. 2018a(Alrahahleh et al. , 2018bHeinonen et al. 2018a;Kellomäki et al. 2018). ...
We used forest ecosystem model simulations to study how forest conservation and management intensity affected timber yield, ecosystem carbon stocks, amount of dead wood, and habitat suitability area in a middle boreal forest region of Finland under changing climate over a 90-year simulation period. We used the following forest conservation and management scenarios: baseline forest management (BM), BM with 10 or 20% increase of conservation area with or without intensified forest management (i.e. improved forest regeneration material and forest fertilization). The simulations were done under current climate (reference period of 1981–2010), and Representative Concentration Pathway (RCP) climate change projections under the RCP2.6 and RCP4.5 forcing scenarios. Overall, increasing the forest conservation area decreased timber yield and increased the ecosystem carbon stock, the amount of dead wood and consequently the area of suitable habitat for saproxylic species. The use of intensified forest management reduced the loss of timber yield, increased ecosystem carbon stock, the amount of dead wood and area of suitable habitat for saproxylic species. At the end of simulation period, the use of intensified forest management even overcompensated (4–6% higher) the timber loss from 10% increase of conservation area. Under changing climate, timber yield, the amount of dead wood and the area of suitable habitats for saproxylic species increased. To conclude, with intensified forest management it is possible, in the short term, to decrease the loss of timber yield through increased forest conservation area and in the long term maintain or even increase it compared to baseline forest management.
... The mechanical stability, hence wind resistance of a forest stand depends on each individual tree as the failure of a single trees can initiate the collapse of the whole stand [22,23]. Accordingly, species, dimensions, and especially stand characteristics, such as soil, are principal factors determining collective stability of trees [8,24,25]. ...
... In the southern boreal and hemiboreal forests, silver birch (Betula pendula Roth.) is a common tree species with high economic and ecological value [22,23,30]. Birch is a shade-intolerant pioneer tree species with high morphological plasticity [15,31,32], which is believed to tolerate a wide range of weather conditions, though show some sensitivity to water deficit in summer [33]. ...
Storms and wind damage are the main cause of biomass loss in forests of Northern Europe, as well as they are synergic with the disturbances causing intense water and temperature stress. This highlights the necessity for climate-smart management at landscape level coupling ecological demands of forestry species with their wind resistance. Silver birch (Betula pendula Roth.), which is highly plastic species, appears to be promising for a wider application under such conditions, as it is believed to tolerate wide range of weather conditions. Though silver birch can be sensitive to water deficit and windthrow, local information on its wind tolerance in sites with different moisture regimes is advantageous. Mechanical stability of 71 mid-aged silver birches (Betula pendula Roth.) growing in seven dry (Hylocomiosa) and five periodically waterlogged (Myrtilloso-sphagnosa) sites with mineral soils in Latvia (hemiboreal lowland conditions) were assessed by the destructive static pulling tests. Site type had a significant, yet intermediate effect on the stability of silver birch. As expected, trees under periodically waterlogged conditions were more prone to collapse under static loading, however, they showed a better resistance to primary failure (beginning of wood structure deformation). Uprooting was the most common form of tree collapse. Surprisingly, considering similar root depths, stem breakage was more frequent in the periodically waterlogged than dry sites (21.9 vs. 5.1%, respectively), indicating high loading resistance of roots, supporting high plasticity and wind resistance of the studied metapopulation of silver birch. Nevertheless, in the periodically waterlogged sites, the difference between forces needed to cause primary and secondary (collapse) failures of stem decreased with age/size, implying necessity for optimization of rotation length. Accordingly, quantification of wind resistance can aid climate-smart selection of species for forest regeneration depending on landscape, suggesting birch as wind resistant option under periodically waterlogged conditions.
... In the future, the growth conditions of tree species in boreal and hemiboreal forests will be determined by species-specific responses to the altered climatic conditions. Studies based on global climate model projections have revealed that, in the southern boreal regions in Europe, the silver birch (Betula pendula Roth) will benefit most from climate change in terms of volume growth, yield, and carbon stock (Peltola et al. 2010;Alrahahleh et al. 2018). In hemiboreal forests, based on a tree-ring analysis, the silver birch had the highest tolerance to historic weather fluctuations compared to other tree species, such as the Scots pine (Pinus sylvestris L.), Norway spruce (Picea abies (L.) Karst.), and European beech (Fagus sylvatica L.) . ...
... In recent years, forest regeneration by birch has been favored due to the low browsing damage, the possibility to regenerate stands naturally with minimal costs, and European Union subsidies that encourage creating mixed deciduous-coniferous stands. The increasing share of birch forests in Baltic countries and Fennoscandia (Kellomäki et al. 2008;Alrahahleh et al. 2018) highlights the importance of further knowledge to sustain forest productivity and resistance to wind damage. ...
Strong wind is the major natural disturbance in European forests, that periodically causes tremendous damages to forestry. Yet, factors that affect the probability of wind damage for birch ( Roth and Ehrh.), the most common deciduous tree species in hemiboreal forests, are studied scarcely. This study aimed to assess the effects of several tree- and stand-scale variables on the probability of wind damage to birch using data from the Latvian National Forest Inventory (2004â2018), and determine individual tree characteristics that affect the height of the stem breakage. The data analysis was done using the Bayesian binary logistic generalized linear mixed-effects model and a linear mixed-effects model. The probability of wind damage significantly increased by stand age, basal area, and slenderness ratio. Trees with prior damage had a significantly higher probability (odds ratio 4.32) for wind damage. For wind-damaged trees, the snapping height was significantly decreased by an increase in the slenderness ratio (â=â0.03) and prior damage (â=â0.003). Previously damaged trees were more frequently (73%) snapped in the lowest 40% of tree height than trees without prior damage (54%). The probability of wind damage is largely set by factors related to the selection of site, species composition, and rotation. The damage probability could be decreased by management measures that lower competition within the stand with particular regard to preserving intact remaining trees during these manipulations. Factors that reduce the probability of the damage simultaneously increase the snapping height, emphasizing their relevance for mitigation of the wind damages. Betula pendula B. pubescens p p
... The responses of forests to climate change may differ greatly at the regional level. This is related to differences in the prevailing environmental conditions (climate, site), current forest structure (age, species) and forest management regimes (Bergh et al. 2003;Briceño-Elizondo et al. 2006;Garcia-Gonzalo et al. 2007;Kellomäki et al. 2008;Lindner et al. 2010;Alrahahleh et al. 2018). Particularly under severe climate warming, the growth and success of Norway spruce are expected to decrease in Finland, especially on southern upland forest sites, if the growing conditions (temperature and water availability) become suboptimal for its growth (Briceño-Elizondo et al. 2006;Jyske et al. 2010;Kellomäki et al. 2018;Ruosteenoja et al. 2018). ...
... At the same time, they predict a slight to moderate increase in precipitation in the north, but only a slight increase (GFDL-CM3 RCP8.5), or a decrease (HadGEM2-ES RCP8.5), in precipitation in the south. Under such severe climate change outlooks, an increased cultivation of Norway spruce may decrease the growth and volume of growing stock, especially under southern boreal conditions, more than predicted, based on the multi-model means of the GCMs (Alrahahleh et al. 2018). Consequently, the severe climate projections (HadGEM2-ES RCP8.5 and GFDL-CM3 RCP8.5) may affect the wind damage risk even more than the tree species preferences in forest regeneration, which should be considered in forest management decision making. ...
... Depending on the severity of the climate change projection, radically different adaptive measures for forestry might be useful. For example, Norway spruce could grow well on certain sites under less severe climate projections and thus would be preferred in forest regeneration, but this would not be the case for more severe climate projections (Alrahahleh et al. 2018). Therefore, the use of different individual GCM projections under RCPs is required in considering the uncertainties in the model predictions for forest growth and dynamics and consequently for the wind damage risks to forests. ...
We studied how the use of certain tree species in forest regeneration affected the regional wind damage risks to Finnish boreal forests under the current climate (1981–2010) and recent-generation global climate model (GCM) predictions (i.e., 10 GCMs of CMIP5, with wide variations in temperature and precipitation), using the representative concentration pathways RCP4.5 and RCP8.5 over the period 2010–2099. The study employed forest ecosystem and mechanistic wind damage risk model simulations on upland national forest inventory plots throughout Finland. The amount of wind damage was estimated based on the predicted critical wind speeds for uprooting trees and their probabilities. In a baseline management regime, forest regeneration was performed by planting the same tree species that was dominant before the final cut. In other management regimes, either Scots pine, Norway spruce or silver birch was planted on medium-fertility sites. Other management actions were performed as for a baseline management. The calculated amount of wind damage was greatest in southern and central Finland under CNRM-CM5 RCP8.5, and the smallest under HadGEM2-ES RCP8.5. The most severe climate projections (HadGEM2-ES RCP8.5 and GFDL-CM3 RCP8.5) affected the wind damage risk even more than did the tree species preferences in forest regeneration. The situation was the opposite for the less severe climate projections (e.g., MPI-ESM-MR RCP4.5 and MPI-ESM-MR RCP8.5). The calculated amount of wind damage was clearly greater in the south than in the north, due to differences in forest structure. The volume of growing stock is much higher in the south for the more vulnerable Norway spruce (and birch) than in the north, which is opposite for the less vulnerable Scots pine. The increasing risk of wind damage should be taken into account in forest management because it could amplify, or even cancel out, any expected increases in forest productivity due to climate change.
... Deciduous trees become more dominant in conifer forests [141] Improved EFN availability → change in ant species composition [85] Warming Among alien invasive plant species more efficient EFN producers [142] Ants can move to invasive plant species [142] Elevated O 3 ...
... Leakage of carbohydrates from bark cracks of boreal deciduous trees could also be an important buffer to prevent drastic ecological changes in ant faunal composition and behavior under climate change-related invasion of EFN-bearing trees. The projected increase in the proportion of Betula pendula and B. pubescens in the forested area of Finland from 17% to 23% during this century [141] suggests that the role of birch as a carbohydrate source for wood ants in future forests could be more important than now. By providing spring sap leaking [174] before the availability of aphid honeydew [78] until the end of autumn defoliation [177,178], birches will provide an alternative carbohydrate source for EFN-bearing tree species during the whole growing season. ...
Carbohydrate-rich extrafloral nectar (EFN) is produced in nectaries on the leaves, stipules, and stems of plants and provides a significant energy source for ants and other plant mutualists outside of the flowering period. Our review of literature on EFN indicates that only a few forest plant species in cool boreal environments bear EFN-producing nectaries and that EFN production in many boreal and subarctic plant species is poorly studied. Boreal forest, the world’s largest land biome, is dominated by coniferous trees, which, like most gymnosperms, do not produce EFN. Notably, common deciduous tree species that can be dominant in boreal forest stands, such as Betula and Alnus species, do not produce EFN, while Prunus and Populus species are the most important EFN-producing tree species. EFN together with aphid honeydew is known to play a main role in shaping ant communities. Ants are considered to be keystone species in mixed and conifer-dominated boreal and mountain forests because they transfer a significant amount of carbon from the canopy to the soil. Our review suggests that in boreal forests aphid honeydew is a more important carbohydrate source for ants than in many warmer ecosystems and that EFN-bearing plant species might not have a competitive advantage against herbivores. However, this hypothesis needs to be tested in the future. Warming of northern ecosystems under climate change might drastically promote the invasion of many EFN-producing plants and the associated insect species that consume EFN as their major carbohydrate source. This may result in substantial changes in the diet preferences of ant communities, the preventative roles of ants against insect pest outbreaks, and the ecosystem services they provide. However, wood ants have adapted to using tree sap that leaks from bark cracks in spring, which may mitigate the effects of improved EFN availability.
To assess the impacts of climate change on vegetation from stand to global scales, models of forest dynamics that include tree demography are needed. Such models are now available for 50 years, but the currently existing diversity of model formulations and its evolution over time are poorly documented. This hampers systematic assessments of structural uncertainties in model‐based studies.
We conducted a meta‐analysis of 28 models, focusing on models that were used in the past five years for climate change studies. We defined 52 model attributes in five groups (basic assumptions, growth, regeneration, mortality and soil moisture) and characterized each model according to these attributes. Analyses of model complexity and diversity included hierarchical cluster analysis and redundancy analysis.
Model complexity evolved considerably over the past 50 years. Increases in complexity were largest for growth processes, while complexity of modelled establishment processes increased only moderately. Model diversity was lowest at the global scale, and highest at the landscape scale. We identified five distinct clusters of models, ranging from very simple models to models where specific attribute groups are rendered in a complex manner and models that feature high complexity across all attributes.
Most models in use today are not balanced in the level of complexity with which they represent different processes. This is the result of different model purposes, but also reflects legacies in model code, modelers' preferences, and the ‘prevailing spirit of the epoch’. The lack of firm theories, laws and ‘first principles’ in ecology provides high degrees of freedom in model development, but also results in high responsibilities for model developers and the need for rigorous model evaluation.
Synthesis. The currently available model diversity is beneficial: convergence in simulations of structurally different models indicates robust projections, while convergence of similar models may convey a false sense of certainty. The existing model diversity—with the exception of global models—can be exploited for improved projections based on multiple models. We strongly recommend balanced further developments of forest models that should particularly focus on establishment and mortality processes, in order to provide robust information for decisions in ecosystem management and policymaking.
