Scots Pine Stands Research Articles

Carbon and Water Fluxes in a Temperate Scots Pine Chronosequence Study in Poland: An EC Measurement Story from an ICOS-Aspiring Country

Long-term measurements of greenhouse gases, and consequently the carbon, water, and nitrogen cycles, have been the focus of numerous studies for decades. Currently, the most accurate and widely used method for real-time, spatially-averaged estimates of these fluxes is the eddy covariance technique (EC). Over time, individual sites across Europe have been integrated into the Integrated Carbon Observation System (ICOS), creating a network with standardized measurement and data processing protocols, thereby producing high-quality, directly comparable results. Since forests play a major role in the land CO2 sink both globally and in Europe, there is naturally a substantial number of forest EC sites within ICOS. However, there are still well-equipped research sites that, for various reasons, are not yet included in this network. A notable example is Poland, the ninth largest country in Europe by area (and seventh by population), which also marks the eastern border of the European Union. In this presentation, we aim to highlight the most interesting results from a network of Scots pine forest sites in Poland, which have been measuring EC CO2 and H2O fluxes for periods ranging from a few to over 10 years. The primary goal is not only to share the results of our analysis but also to explore new collaboration opportunities with the eLTER network to fully utilize the potential of our sites beyond greenhouse gas fluxes. To provide context for why Scots pine (Pinus sylvestris) was chosen for the Polish network, it is the most widespread pine species globally and the second most distributed conifer after the common juniper (Juniperus communis). Its natural Euro-Asian range spans vast areas, and in Poland, Scots pine dominates 58.6% of the total forest area. Additionally, the mean age of Scots pine trees in Poland is 62 years, meaning that most of them are mature stands. After several years of continuous EC and basic meteorological measurements, complemented by carbon stock inventories in soil and biomass, we addressed the following research questions: What is the nature of the relationship between the age of temperate, managed Scots pine stands, and their sequestration abilities (chronosequence approach)? At what age do these stands reach their maximum sequestration potential? Does the classic forest inventory-based carbon accumulation in woody biomass align with the EC-derived Net Ecosystem Exchange estimates at both annual (based on dendrometers) and multiannual (forest inventory) scales? What is the nature of the relationship between the age of temperate, managed Scots pine stands, and their sequestration abilities (chronosequence approach)? At what age do these stands reach their maximum sequestration potential? Does the classic forest inventory-based carbon accumulation in woody biomass align with the EC-derived Net Ecosystem Exchange estimates at both annual (based on dendrometers) and multiannual (forest inventory) scales? Additional questions related specifically to the impact of different forest management practices on the carbon budget of temperate Scots pine forests were also explored and will be discussed here. In conclusion, although the presented Scots pine EC sites are not yet part of ICOS, the results may be of significant interest to other forest site Principal Investigators (PIs) in this network. This comprehensive, long-term dataset on carbon and water flux exchange between the atmosphere and one of Europe’s most common forest tree species holds relevance not only for climate-related impacts but also for socio-economic factors, as Scots pine is a crucial wood source species.

Effects of logging residue treatment and mechanical site preparation on below- and aboveground biomass production in Scots pine stands

The increasing demand for renewable energy has led to a surge in biomass harvesting from forest ecosystems. However, intensive biomass extraction, especially logging residue (LR) removal and mechanical site preparation (MSP), may affect long-term forest productivity. This study aimed to assess the effects of three MSP methods (plowing and planting in furrows, disc trenching, bedding and planting in raised beds) and three LR management strategies (complete removal, leaving residues, and comminution) on above- and belowground biomass production in Scots pine (Pinus sylvestris L.) stands 17 years after planting. The experiment was conducted in northwestern Poland on Albic Brunic Arenosols with low fertility. The experiment consisted of 27 plots in a randomized complete block design. The tree measurements included diameter at breast height (DBH), tree height, stand density, basal area, stand volume and biomass, which were analyzed using two-way ANOVA. Significant differences in DBH and tree height were detected between the MSP methods. Furrowing resulted in the greatest growth, whereas bedding produced the lowest DBH and height. Among the LR treatments, tree height was lowest for comminution. However, no significant differences were found in stand biomass, basal area, or stand volume across the treatments. These findings suggest that the MSP and LR management methods have short-term effects on tree growth but do not significantly influence long-term stand productivity. These results highlight the importance of performing long-term experimental trials to assess the sustainability of forest management practices.

Effects of logging residue on the growth and properties of the humus layer in Scots pine and Norway spruce stands

Effects of logging residue on the growth and properties of the humus layer in Scots pine and Norway spruce stands

Short-Term Ground Vegetation Responses to Fertilization in Latvian Forests: Effects on Species Richness and Diversity

This study investigated the impact of forest fertilization on ground vegetation in deciduous and conifer stands across different forest site types (forests with drained mineral soils, forests with drained organic soils, and dry upland forests), stand age groups (young, middle-aged, and pre-mature), and fertilizer types (ammonium nitrate (NH4NO3) and wood ash alone, and both together). Ground vegetation was surveyed one to three years after fertilizer application, with the projected ground cover of individual species in the moss and herb layers determined. Thus, results reflect short-term impact of fertilization. Species richness and diversity (Shannon diversity index, H′) were compared between fertilized and control (unfertilized) plots. The results show that species diversity in the moss layer of silver birch stands was significantly affected by fertilization, while species richness was significantly influenced by the interaction between fertilization and forest site type. Differences between control and fertilized plots in birch stands suggest a potentially negative response of the moss layer to fertilization. In contrast, no significant effect of fertilization was observed in Norway spruce stands, where site type and stand age emerged as significant factors. In Scots pine stands, where NH4NO3 was applied alone, fertilization had a significant impact on both species richness and diversity in the herb layer. In the moss layer, a marginally significant effect was found for the interaction between fertilization and stand age. NH4NO3 alone appeared to enhance herb layer richness, although its effect on species diversity was more variable. Our study highlights the context-dependent nature of fertilization effects on species richness and diversity in Latvian hemiboreal forest ecosystems.

Effects of wood ash, nitrogen, and biosolids fertilisation on the growth and soil properties of Scots pine and Norway spruce stands

Effects of wood ash, nitrogen, and biosolids fertilisation on the growth and soil properties of Scots pine and Norway spruce stands

Canopy openness rather than tree species determines atmospheric deposition into forests.

Canopy openness rather than tree species determines atmospheric deposition into forests.

Volume growth responses of Scots pine and Norway spruce to nitrogen fertilization: quantitative synthesis of fertilization experiments in Finland

The effects of nitrogen (N) fertilization on tree growth have been studied widely in boreal forests in Finland, but a quantitative synthesis is still lacking. We performed a quantitative synthesis on volume growth responses to N fertilization in Scots pine (Pinus sylvestris L.) and Norway spruce (Picea abies (L.) Karst.) stands in experiments established on mineral soils across Finland. Our study employed findings of 9 published studies including 108 Scots pine and 57 Norway spruce observations covering a wide range of N fertilization treatments, as well as forest stand- and climatic conditions. Based on these observations, we built linear mixed models to describe the N fertilization-induced annual volume growth response of Scots pine and Norway spruce stands. Our models showed that the N dose was the best predictor for volume growth response, and the growth response increased linearly with increasing N dose for both tree species. The volume growth responses also increased along with an increase in mean annual precipitation. The annual volume growth response decreased with the time since fertilization. For Scots pine, the best model also contained site fertility; increase in site fertility increased the volume growth response. These findings emphasize the need for site-specific precision fertilization schemes to sustainably improve growth and carbon sequestration of boreal forests.

Trade-offs and management strategies for ecosystem services in mixed Scots pine and Maritime pine forests

AbstractMixed forests are increasingly recognized for their resilience to climate change and enhanced ecosystem services (ESs) provision, making them a focal point for sustainable forest management strategies. This study examines the trade-offs in ESs provision between pure and different proportions of mixed stands of Scots pine (Pinus sylvestris L.) and Maritime pine (Pinus pinaster Ait.) in the Northern Iberian Range, Spain. Using the SIMANFOR simulation platform, we evaluated various silvicultural scenarios developed to obtain different ESs such as carbon sequestration, timber and mushroom yields. Our findings reveal that ESs provision varies depending on the forest type (pure or mixed) and the mixture proportion, following different trends on each ES. The initial species proportions and their maintenance were less critical than the management approach itself, which significantly influenced ESs outcomes. Focusing solely on individual ESs can lead to trade-offs, as highlighted by our study on silviculture focused on large saw timber yields. However, adopting a balanced approach that considers multiple ESs can mitigate these trade-offs. Our findings underscore the effectiveness of this approach in maximizing yields of mushrooms, sequestered carbon, and small saw timber. This research provides valuable insights for forest managers aiming to balance productivity and sustainability in ESs provision, providing strategies to maximize compatible ESs effectively.

Genomic Data Support the Revision of Provenance Regions Delimitation for Scots Pine.

Scots pine is a crucial component of ecosystems in Europe and Asia and a major utility species that comprises more than 60% of total forest production in Poland. Despite its importance, the genetic relationships between key conservation and the commercial value of Scots pine ecotypes in Poland remain unclear. To address this problem, we analyzed 27 populations (841 trees) of the most valuable Polish Scots pine ecotypes, including the oldest natural stands in all 24 regions of provenance established for the species in the country. By examining maternally inherited mitochondrial markers, nuclear microsatellite loci, and thousands of SNP markers from a genotyping array, we evaluated the genetic structure between and within them. These multilevel genomic data revealed high genetic similarity and a homogeneous structure in most populations, suggesting a common historical origin and admixture of populations after the postglacial recolonization of Central Europe. This research presents novel data on existing genomic resources among local ecotypes defined within strictly managed Polish regions of provenance, challenging their validity. Formal tests of the progeny of seed stands are needed to check whether the diversity in adaptation and quantitative traits still supports the delineation of provenance regions. In parallel, the health status of selected populations and the viability of seeds from these regions should be monitored to detect early-stage symptoms of their environmental stress. It seems reasonable that periodic shortages of forest reproductive material (FRM) in a given region of provenance could be supplemented with the one from other regions that match their climatic envelope. Together, our results have important implications for the management of native Scots pine stands, particularly elite breeding populations, as they contribute to the discussion of the boundaries of provenance regions and the transfers of FRM that face increasing climate change.

Dynamic site index models sensitive to ecoregional variability for Scots pine stands in Western Black Sea Region of Türkiye.

Site productivity, defined as the production amount of the stand at a specific age, has a significant impact on the growth of the stand and site index is used as an indicator of site productivity. The objective of this study is to develop ecoregion-based dynamic site index models for Scots pine (Pinus sylvestris L.) stands in the Kastamonu and Sinop regions of Türkiye. The mixed-effects modeling approach allowing for the inclusion of ecoregions in the models was used to develop dynamic site index models, and the models derived from seven base models were tested. The best model was selected based on statistical criteria. As a result of statistical analyses and graphical examinations, the King-Prodan model was found to yield the best predictive results in terms of growth patterns. The site index model based on the King-Prodan method produced a coefficient of determination (R2) of 0.977. The statistical criteria for this model are as follows: Akaike information criterion (AIC) of 4931.052, Bayesian information criterion (BIC) of 4968.933, root mean square error (RMSE) of 1.218, and mean error (ME) of - 0.036. The F-test was used to test whether there was a statistically significant difference in dominant heights between ecoregions. The results demonstrated that the dominant heights exhibited statistically significant differences among the ecoregions. Consequently, it is of paramount importance to utilize ecoregion-based dynamic site index models in order to achieve reliable and accurate predictions.

A low-cost alternative to LiDAR for site index models: applying repeated digital aerial photogrammetry data in the modelling of forest top height growth

Abstract Environmental and forest structural information derived from remote sensing data has been found suitable for modelling forest height growth and site index and therefore forest productivity assessment, with the advances in airborne laser scanning (ALS) playing a major role in this development. While there is growing interest in the use of ALS-derived point clouds, point clouds from high-resolution digital aerial photography (DAP) are also often used for mapping and estimating forest ecosystem properties due to their lower acquisition costs. In this study, we document the applicability of bi-temporal DAP data for developing top height (TH) growth models for Scots pine stands. Our results indicate that DAP data can function as an alternative to traditional TH measurements used in growth modelling when corrected based on a limited sample of field-measured reference TH values. As the correction cannot be constant for each DAP dataset due to the different parameters during data acquisition, we propose a straightforward method for the bias correction of DAP-derived TH estimates. By undertaking iterative random sampling, we were able to find the minimum number of reference measurements needed to calculate the TH correction in order to achieve the desired accuracy of the TH estimations based on DAP. Here, we used ALS data as the reference data; however, the ALS measurements can be replaced by any other reliable source of TH values. The presented method for determining TH can be used not only for site index and forest growth modelling but also in forest inventories.

How to get closer to actual forest stand height using GEDI? A case study in central European Scots pine stands

ABSTRACT Global Ecosystem Dynamics Investigation (GEDI) Satellite Laser Scanning mission plays a key role in forest monitoring, conducting global measurements of forest height and structure. However, the use of various stand height metrics and definitions applied to describe forest height complicates study comparisons and the selection of most suitable GEDI metric for stand height determination. Our study was focused on finding the optimal GEDI relative height (rhG) metric to describe the height of Scots pine stands. We compared GEDI rhG parameters with several metrics commonly used as reference forest stand height (a series of Airborne Laser Scanning point cloud percentiles and relative height metrics of simulated waveforms; rhSW). Results showed that GEDI rhG metrics in the 0.95–0.99 rank range can accurately describe forest stand height (ALS reference: RMSE ≤ 2.79 m; %RMSE ≤12.57%; rhSW reference: RMSE ≤ 2.80 m; %RMSE ≤12.21%). Moreover, our analyses suggested that different rhG metrics can be used to describe forest stand height depending on its height and canopy cover to increase measurements accuracy. We recommended a set of GEDI rhG metrics for adequate height measurements of Scots pine stands that can be used by forestry practitioners.

Changes in Ground Cover Layers, Biomass and Diversity of Vascular Plants/Mosses in the Clear-Cuts Followed by Reforested Scots Pine until Maturity Age

The distribution of Scots pine (Pinus sylvestris L.) forests, particularly the Vaccinio myrtillo-Pinetum type, is determined by edaphic conditions, and although clear-cutting is used to promote regeneration, it remains controversial. This study evaluated the changes in non-living (forest floor and dead wood) and living (mosses, herbs, and dwarf shrubs) ground cover in clear-cut areas and reforested Scots pine stands. Continuous ground cover studies were conducted in clear-cuts, with samples collected over three years after clear-cutting, while data from 8–80-year-old and mature Scots pine stands were collected using the chronological series method with a consistent methodology in temporary plots. The research has shown that, as ecosystem recovery progresses, similarity to the mature forest increases, and a threshold stand age has been identified, beyond which the ecological changes induced by clear-cutting diminish. The study findings demonstrated that clear-cutting in Pinetum vaccinio-myrtillosum-type forest stands lead to a rapid increase in herb and dwarf shrub cover due to reduced competition for light and nutrients. However, clear-cutting caused a significant decline in forest-specific species and a drastic reduction in forest floor and dead wood mass, with a gradual recovery of moss cover over 10–30 years. These findings highlight the importance of managing clear-cutting practices to balance immediate vegetative responses with long-term ecosystem stability and biodiversity conservation.

Structural Characteristics of the Pine Stands on Degraded Lands in the South-East of Romania, in the Context of Climate Changes

The present research was carried out in stands of Scots pine and black pine, pure or mixed with deciduous trees, installed on degraded lands from the Curvature Subcarpathian area, Romania, in a representative network of permanent research plots and followed the analysis of the structural diversity and stability indicators of these stands at different ages and in different conditions of degraded lands. The relationships between the quantitative variables with reference to the structure were established by analyzing the significance of the Pearson correlation coefficient (r) and also including datasets of slenderness indexes, which were classed into three domains of vulnerability to abiotic factors (like wind and snow). The compositional diversity of pine stands (pure or mixed with deciduous ones) is different in relation to age and is correlated with the structural diversity. The obtained correlation coefficients (r Pearson) express very strong and significant relationships between biometric parameters (h x Dbh, h x Lc%, Dc x Dbh, and Lc% x Dbh) of the structural diversity (r = 0.800–0.930), which is important for the analysis of the stability and vulnerability of pine forests. The strong correlation between the analyzed variables expresses a weak vulnerability to the action of harmful abiotic factors and the increase in the stability and resilience of the studied stands, especially of over 50 years old. In the old pine stands, the low-vulnerability domain (I < 0.80) is the best represented one, with an average of 64.01% from the total number of trees. At this age, trees with DBH > 22 cm fall into the low-vulnerability category. The explanation is that the stands were affected in their youth by the action of snow and wind, which, combined with the silvotechnical works performed, led to their compositional and structural diversification and increased stability. The young (<45 years) and pure-pine stands with higher consistency (>0.8) and even-aged structure are the most vulnerable to abiotic factors due to the fact that a large number of trees are passing gradually into the higher cenotic classes.

Allometry and biomass dynamics in temperate mixed and monospecific stands: Contrasting response of Scots pine (Pinus sylvestris L.) and sessile oak (Quercus petraea (Matt.) Liebl.)

Mixed forests generally outperform monospecific forests in terms of productivity, stability, and resilience and are becoming increasingly important for sustainable forest management. However, accurate estimates of tree biomass allocation, as well as aboveground and component biomass in mixed forests, remain scarce. Our study addressed three different objectives to identify differences in biomass between mixed and monocultures and develop biomass models: (1) identification of biomass growth patterns in mixed and monoculture stands using analysis of covariance (ANCOVA), (2) investigation of the best fitting approach to modeling aboveground biomass using logarithmic regression and nonlinear mixed-effects models, and (3) fitting compartment biomass proportion models by Dirichlet regression, considering the additivity property. We analyzed 52 harvested trees from six plots within an experimental triplet in northern Spain, consisting of mixed and single-species stands of Scots pine (Pinus sylvestris L.) and sessile oak (Quercus petraea (Matt.) Liebl.). Moreover, diameter at breast height and tree height were used as covariate variables to determine the most accurate and unbiased models. The research findings showed that (i) allometric patterns of individual-tree biomass in mixed stands significantly differed from those in monospecific stands for sessile oak, while those in Scots pine did not change; (ii) nonlinear mixed-effect models demonstrated a better fit – indicated by lower Furnival index values – than logarithmic regression models in predicting aboveground biomass; and (iii) the fitted biomass equations provided good performance and accurate estimates of biomass component proportions compared to those of existing models. Consequently, our results offer a better understanding of biomass and carbon storage within mixed and monoculture forests in the context of climate change.

Needle Biomass Turnover Rate in Scots Pine Stands of Different Ages

Understanding needle biomass turnover rates in Scots pine (Pinus sylvestris L.) stands is crucial for modelling forest ecosystem dynamics and nutrient cycling. This study examined needle litterfall and biomass turnover in Scots pine stands of varying ages in temperate forests (western Poland). The research focused on determining how stand age affects needle biomass, litterfall and the associated turnover rates. Data were collected from 20 Scots pine stands aged 26 to 90 years, and needle litterfall was measured and analysed in relation to stand characteristics such as age, density and biomass. The average annual needle litter production of the sampled Scots pine stands was 2008 kg·ha−1·year−1, similar to the values previously reported for this tree species in other temperate forests in Europe. The average needle biomass turnover rate for sampled Scots pine stands was 23.4%. We could not support the hypothesis that this parameter depended on the age of the Scots pine stand. The needle biomass turnover rate showed a positive correlation with crown length and a negative correlation with stand density due to the very weak correlations; however, further research is needed to confirm these relationships. Despite this, the parameter can be used to estimate needle litterfall and can be applicable to conditions corresponding to those of temperate forests in Central and Western Europe. This study also highlights the need for further research on needle biomass turnover in temperate forests to improve the accuracy of carbon and nutrient cycling models. This work contributes to a deeper understanding of the role of needle litterfall in maintaining soil fertility and forest productivity, offering insights into sustainable forest management and conservation strategies.

The effect of climate change on the radial growth of Pinus sylvestris l. and Quercus robur l. in the stands of Kharkiv green zone

Purpose. To identify the characteristics of the reaction of the radial growth of Scots pine (Pinus Sylvestris L.) and Scots oak (Quercus robur L.) to climate change in the forest-steppe zone of Ukraine. Methods. Dendrochronological, dendroclimatological, and statistical methods are applied. COFECHA and ARSTAN programs were used. Results. The study was conducted in 100-year-old stands of English oak and Scots pine in the Southern Forestry (Left-bank Forest-steppe). The reaction of the radial growth of trees to climate changes was compared for 1960-1987 and 1988-2016. For the dendroclimatic analysis, the de Martonne hydrothermal indices, the Selyaninov hydrothermal coefficient, the forest aridity index, and the O1 hydrothermal coefficient were used. Relative humidity indicators, which are derived from temperature and precipitation, were also used. It was found that in the second period, the sensitivity of the reaction of the radial growth of trees to climate variations increased, which indicates a certain weakening of the stands due to the increase in temperature. Dendroclimatic analysis of Pinus sylvestris L. and Quercus robur L. showed that when comparing the response of the radial growth of trees to climate variations in 1960-1987 and 1988-2016, the condition of both pine and oak weakened, as evidenced by an increase in significant coefficients correlations between growth indices and climatic factors. Conclusions. Pine was found to be more sensitive to climate change compared to oak. At the same time, these species of these trees at this stage were able to adapt to climate change, as evidenced by tree-ring chronologies, which show stable growth during 2010-2016.

Using Cut-to-Length (CTL) Harvester Production Data in Forest Inventories

Determining forest stand characteristics after thinning, in order to assess the quality of the work and update the inventory data of the thinned stand, is one of the few forest management tasks for which an efficient and accurate automation solution has not yet been developed. Currently, forest stand characteristics are determined by a certified inventory expert using manual instruments such as a range finder, digital or manual calliper, and a Bitterlich gauge. Manual measurements add a significant cost to forest management, and automating this process could increase the competitiveness of forest owners in the global timber market, helping reduce human error and providing more detailed information on the condition of stands and the distribution of trees of different dimensions in a stand.The aim of the study is to adapt a method developed in Sweden for the automated estimation of forest stand characteristics after thinning using the HprGallring software to Latvian conditions and to determine accuracy of the modelling-based prediction of stand characteristics.In the study, the height, number, diameter, and species of individual trees after thinning were determined using the sample plot method (according to methods applied in forest resources monitoring) and using photogrammetry as reference data for the study. In some felling areas, the diameters of all trees were measured before and after felling. The data obtained using different methods were compared with updated stand characteristics in the Forest resource database updated by certified inventory experts using plot measurement method.According to the results of the study, HprGallring can provide the data necessary for updating the forest inventory database after thinning, but the accuracy of the modelled projections, as compared to manual measurements, are not yet within the uncertainty range as required by the forest inventory regulations. The average tree height, as indicated in the State Forest Register, matches the HprGallring estimates within the regulatory uncertainty limits in 67% of Scots pine (Pinus sylvestris L.) stands, 65% of Norway spruce (Picea abies (L.) H.Karst.) stands, and 48% of Birch (Betula sp.) stands. The diameter of an average tree after thinning estimated by the HprGallring is larger than that according to the manual measurement. The average diameter estimated using HprGallring in pine stands matches the data in State Forest Register in 40% of the assessed areas, in 47% for spruce stands, and 35% of birch stands. The accuracy of the predictions needs to be improved to make HprGallring usable in forest inventory, but even now it provides valuable spatial information about the distribution of trees of different dimensions and species within stands, enabling more accurate planning of management methods and spatial redesigning of the forest compartments.

Effects of forest management intensity and climate change severity on volume growth, timber yield, carbon stocks, and the amount of deadwood in Scots pine, Norway spruce, and silver birch stands in boreal conditions

We studied how management intensity and climate severity affect volume growth, timber yield, carbon stocks, and the amount of deadwood in Scots pine ( Pinus sylvestris (L.)), Norway spruce ( Picea abies (L.) Karst.), and silver birch ( Betula pendula Roth.) dominated stands in the Republic of Karelia and Arkhangelsk region of northwest Russia. Using the forest ecosystem model (SIMA) under different climates (current and representative concentration pathway scenarios, RCP4.5 and RCP8.5), no-thinning, low, medium, and high intensity thinning rotational forestry regimes were simulated. Under RCPs, the volume growth and timber yield (5%–53%), carbon stocks (1%–22%), and deadwood amounts (11%–75%) increased for all Scots pine and silver birch stands. The use of low intensity management increased volume growth and carbon stocks (3%–16%) and deadwood amount (up to 60%) under RCPs, but not timber yield (±3%) in these stands. For Norway spruce stands, the volume growth (5%–26%), timber yield (23%–75%), and carbon stocks (5%–15%) decreased under RCP8.5, but deadwood amount increased (up to 142%). Intensive management increased volume growth (4%–19%), timber yield (4%–63%), carbon stocks (up to 14%), and deadwood amounts (up to 49%). Our results highlight that effects of climate severity and management intensity are site and species-specific for Eurasian’s boreal forests.

Kvalitet sjemenskih sastojina bijelog bora (Pinus sylvestris L.) i crnog bora (Pinus nigra Arnold) u Federaciji Bosne i Hercegovine

This research aims to determine the quality of Scots pine (Pinus sylvestris L.) and Austrian pine (Pinus nigra Arnold) seed stands in Federation of Bosnia and Herzegovina, and to recommend measures for the improvement of these stands for producing the highest quality reproduction material of researched species. For this research, 23 traits of trees in fourteen seed stands of Scots pine, and twelve stands of Austrian pine in the Federation of Bosnia and Herzegovina were analysed. Four traits were measured, and nineteen traits were assessed. The results showed the good condition of seed stands of investigated traits for the most of investigated stands. Some of the stands have shown very good quality, and individual selection should be made in them, while in other stands it is necessary to remove part of the trees. Considering the great ecological-vegetation diversity of Bosnia and Herzegovina, a greater number of Scots and Austrian pine seed facilities is needed. When selecting new seed plants of white and black pine, the focus should be on small stands that grow in extreme conditions.