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Central European Forestry Journal
Number of Followers: 2

This is an Open Access Journal

Open Access journal
ISSN (Print) 2454-034X - ISSN (Online) 2454-0358
Published by Sciendo

[389 journals]

Case study of qualitative sorting of raw wood assortments in the
conditions of a forestry enterprise in Slovakia
- Abstract: Valuation of timber growing in commercial forests is a key issue for forest owners, forest enterprises, but also a starting point for long-term planning in the field of forest management. The subjective approach of the evaluator can, to a large extent, lead to inconsistencies in the area of wood qualitative evaluation. This paper aimed to perform an objective qualitative analysis on a selected set of 179 logs of hardwood raw-wood assortments in a selected Forest enterprise in Slovakia. Qualitative analysis, which was performed by the Technical Conditions used by Lesy SR, š.p. confirms the identical classification of raw-wood assortments, in comparison with the classification performed by the management of the forestry enterprise, in 65 logs (36.3% of logs). In 114 (63.7%) logs, the log assortment was classified in another quality class. Most of the logs, which were reclassified to lower quality classes, showed limiting qualitative features of multiple sweep (83 logs), resp. significant simple sweep over 8 cm/m (5 logs), soft rot over 20% of the end diameter area (10 logs), and decaved knots (19 logs). Our work confirmed that the qualitative evaluation of raw-wood assortments in forestry enterprises in Slovakia is not optimal and correct. The work should thus contribute to improving the setting of optimization processes in the timber production phase in forestry enterprises.
  PubDate: Fri, 21 Oct 2022 00:00:00 GMT
Forest inventory based on canopy height model derived from airborne laser
scanning data
- Abstract: Airborne laser scanning (ALS) has emerged as a remote sensing technology capable of providing data suitable for deriving all types of elevation models. A canopy height model (CHM), which represents absolute height of objects above the ground in metres (e.g., trees), is the one most commonly used within the forest inventory. The aim of this study was to assess the accuracy of forest inventory performed for forest unit covered 17,583 ha (Slovakia, Central Europe) using the CHM derived from ALS data. This objective also included demonstrating the applicability of freely available data and software. Specifically, ALS data acquired during regular airborne survey, QGIS software, and packages for R environment were used for purpose of this study. A total of 180 testing plots (5.6 ha) were used for accuracy assessment. The differences between CHM-predicted and ground-observed forest stand attributes reached a relative root mean square error at 10.9%, 23.1%, and 34.5% for the mean height, mean diameter, and volume, respectively. Moreover, all predictions were unbiased (p-value < 0.05) and the strength of the relationships between CHM-predicted and ground-observed forest stand attributes were relative high (R2 = 0.7 – 0.8).
  PubDate: Fri, 21 Oct 2022 00:00:00 GMT
(Fr.) Dyko & B. Sutton in L. stands affected by long-term drought
- Abstract: In this study, the fruit bodies (pycnidial) colonization and spore presence of Sphaeropsis sapinea (Fr.) Dyko & B. Sutton on Scots pine (Pinus sylvestris L.) trees in stands affected by long-term drought in the Czech Republic were evaluated. A total of 520 cones at four sites were evaluated every 1.5 months from June 2019 to December 2020. The pycnidia of S. sapinea in relation to colonization by subcortical insects in inner bark and wood, and wood-decaying fungi a total of 340 trunks at 17 sites during the autumn of 2020 were also evaluated. Pycnidial colonization of S. sapinea on cones was significantly higher at the site with the highest air humidity and significantly lower in the sampling periods of June 2019, August 2019, and November 2019, which were characterized by low precipitation levels. S. sapinea spore presence on cones was significantly higher at sites in Bohemia compared to those in Moravia, in sites with higher air humidity, and in three consecutive sampling periods in March 2020–June 2020. Pycnidial colonization of S. sapinea on trunks was significantly positively dependent on the colonization of subcortical insects in both inner bark and wood, but not with the colonization of wood-decaying fungi. The results of this study show a positive relationship between high humidity and colonization by subcortical insects in inner bark and wood with S. sapinea on Scots pine.
  PubDate: Fri, 21 Oct 2022 00:00:00 GMT
Perceived climate change risks among other risks affecting private forest
owners in a top-down decision-making process
- Abstract: Forest management adaptation to climate change is a matter of forest type, disturbances regime, and forest owners’ behavior face the climate change issue. Knowing factors that determine people respond to climate change challenges is essential to explaining their perceptions of climate change adaptation. We have conducted astudy in North-Eastern Romania applying the Model of Private Proactive Adaptation to Climate Change. The aim was to identify private forest owners’ perceptions about climate change and forest management threats and constraints and to analyse what variables differentiate private forest owners’ adaptation behavior. The PFOs with higher education were aware of the forest regime regarding private management. They knew how to assess climate change risk, while those with secondary education were the only interest was obtaining wood. The PFOs’ risk experience played an important role in adaptation. The perceptions and beliefs of PFOs were strongly influenced by socio-economic status, and they believe in climate change effects on forests but not on theirs. Adaption has become less urgent because forest management problems blur climate change beliefs. Assuming that the Romanian PFOs’ perceptions and beliefs about climate change will follow the European trend, they will want to improve their knowledge about climate change impacts and adaptive measures. Therefore, aggregating the interested PFOs, creating suitable communication channels, and organizing trainings on forest management adaptation to climate change will be needed to prevent this need.
  PubDate: Fri, 21 Oct 2022 00:00:00 GMT
Technological employment of fire-fighting adapter to increase the
efficiency of extinguishing forest fires
- Abstract: The paper presents the results of the solution defining the possible application of the adapter as a fire-fighting mobile device with a base machine of a forest wheeled skidder (LKT) in the fire protection of forests in the Slovak Republic. Following the challenging accessibility to fire-fighting machinery during any intervention in forestry operation, the main aim was formulated. It will be about basic technical parameters of the DATEFF fire-fighting adapter, resulting from operational measures and following specification of its tactical deployment in extinguishing forest fires. This fact also follows from based on statistically processed data on fire in state forests of the Slovak Republic in the last ten years. The greatest damage occurs mainly the forests at a slope gradient of 16%. Designed fire adapter is structurally designed mainly to these terrains. Regarding its design and technical parameters, the proposed DATEFF adapter can be employed tactically as fire-fighting mobile device. In the case of an unavailable water source without access to the forest transport network, the adapter can be used as a part of long-distance water transport or as a mobile device for emergency import of material. Another option is to use it as a water tank in inaccessible terrain with the possibility of refilling using a Bambi bag and a helicopter. This fire-fighting adapter DATEFF is designed for forest wheel tractors that reach 40% slope availability, are able to work on the stand area, overcome obstacles and are available in sufficient quantities in all Slovak forest owners.
  PubDate: Fri, 21 Oct 2022 00:00:00 GMT
Spring phenology of oak stands in the Western Carpathians: validation of
satellite metrics from MODIS using ground-based observations
- Abstract: The study focuses on the validation of the leaf unfolding (LU) onset of oak stands in the Western Carpathians in 2000–2021 derived from MODIS satellite data. LU onset was derived from the annual trajectories of the Normalised difference vegetation index (NDVI) fitted with a double sigmoid logistic function. The satellite metric Growing speed day (GSD) corresponding to the LU onset is represented by the first derivative of the sigmoid function. Ground-based observations from 22 phenological stations of the Slovak Hydrometeorological Institute (SHMI) were used to validate the date of GSD. The results showed a good agreement between the medians of ground- and satellite-based LU onset dates. In addition to the median, the LU onset at the 5th and 95th percentiles were compared. For both percentiles, we found differences in the onset from MODIS and SHMI. The 5th percentile of the LU onset derived from MODIS was determined later than the one from SHMI data. With the 95th percentile, it was the opposite. As a result, the range determining the duration of LU onset from MODIS was significantly shorter than from SHMI observations. The trend analyses over the period 2000–2021 revealed a shift to the earlier onset of LU ~ 0.33 day.year−1 (p = 0.13) from satellite and ~ 0.32 day.year−1 from ground-based observations (p = 0.08). The validated LU onset and trends using the median allow analysing of the oak stands response to changing environmental conditions. However, the differences at the 5th and 95th percentiles, i.e. at the beginning and the end of the LU onset duration, remained unexplained.
  PubDate: Fri, 21 Oct 2022 00:00:00 GMT
Dendrochronological data from twelve countries proved definite growth
response of black alder ( [L.] Gaertn.) to climate courses across its
distribution range
- Abstract: Black alder (Alnus glutinosa [L.] Gaertn.) is an important component of riparian and wetland ecosystems in Europe. However, data on the growth of this significant broadleaved tree species is very limited. Presently, black alder currently suffers from the pathogen Phytophthora and is particularly threatened by climate change. The objective of this study was to focus on the impact of climatic variables (precipitation, temperature, extreme climatic events) on the radial growth of alder across its geographic range during the period 1975–2015. The study of alder stands aged 46–108 years was conducted on 24 research plots in a wide altitude range (85–1015 m) in 12 countries of Europe and Asia. The most significant months affecting alder radial growth were February and March, where air temperatures are more significant than precipitation. Heavy frost and extreme weather fluctuations in the first quarter of the year were the main limiting factors for diameter increment. Within the geographical setting, latitude had a higher effect on radial growth compared to longitude. However, the most important variable concerning growth parameters was altitude. The temperature’s effect on the increment was negative in the lowlands and yet turned to positive with increasing altitude. Moreover, growth sensitivity to precipitation significantly decreased with the increasing age of alder stands. In conclusion, the growth variability of alder and the number of negative pointer years increased with time, which was caused by the ongoing climate change and also a possible drop in the groundwater level. Riparian alder stands well supplied with water are better adapted to climatic extremes compared to plateau and marshy sites.
  PubDate: Tue, 23 Aug 2022 00:00:00 GMT
Biomass allocation and carbon stock in Douglas fir and Norway spruce at
the tree and stand level
- Abstract: The effect of changing tree species composition in favor of a greater representation of Douglas fir at the expense of Norway spruce on the carbon pool of Central European forests has not yet been investigated. Here, we compare the allocation of aboveground biomass and carbon stock in Douglas fir and spruce at the tree and stand level. At the tree level, Douglas fir accumulated, on average, 16.9% more aboveground biomass than Norway spruce. A greater amount of biomass was allocated mainly in the wood and bark of Douglas fir stem. For these biomass compartments, the difference between Douglas fir and Norway spruce was 21.1% and 60.3%, respectively. Spruce allocated more biomass in the crown, where the difference was 25.6% compared to Douglas fir. In needle biomass, Norway spruce exceeded Douglas fir by 84%. At the stand level, the analysis of model stands revealed that pure Norway spruce stands accumulated more carbon in the high and medium quality sites. As the site quality decreased, so did the differences in the amount of stored carbon. The higher carbon sink in Norway spruce stands was also confirmed in the analysis of real Norway spruce and Douglas fir stands. The difference in the carbon stock of young, medium-aged, and mature stands was 11.5%, 14.8%, and 1%, respectively. The positive balance in favor of spruce is mainly due to significantly higher numbers of trees per ha in Norway spruce stands. A positive effect of a greater representation of Douglas fir on the carbon budget of forest stands was not confirmed.
  PubDate: Tue, 23 Aug 2022 00:00:00 GMT
Biomass distribution, allocation and growth efficiency in European beech
trees of different ages in pure even-aged stands in northeast France
- Abstract: Determination of the biomass and biomass increment of trees in managed stands is a pre-requisite for estimating the carbon stocks and fluxes, in order to adapt the forests to new climatic requirements, which impose to maximize the CO2 retained by forests. Tree biomass and biomass increment equations were formerly developed in two young experimental beech stands in the Hesse forest (NE France). To extend such a study to beech stands of different age classes, it was necessary to build biomass and biomass increment equations that could be used for any age, called generalized biomass equations. For that, trees were sampled in plots covering a large age range in Hesse forest, and in each plot several trees were chosen to represent the different social classes. Compatible biomass and biomass increment equations for the different tree compartments and their combination in above and belowground tree parts were developed and fitted, allowing the analysis of the variations of the biomass distribution and allocation with tree age. Stem growth efficiency (stem growth per unit of leaf area) appeared dependent on tree age and tree social status. The biomass and biomass increment equations established for beech allow the estimation of the biomass and carbon stocks and fluxes (NPP) for the even-aged beech stands of the Hesse forest, whatever their age. These equations could also be used to analyze the effects of silvicultural treatments on the biomass and carbon stocks and fluxes of beech stands, using the available stand growth and yield models of beech.
  PubDate: Tue, 23 Aug 2022 00:00:00 GMT
The principle of space-for-time substitution in predicting spp. biomass
change under climate shifts
- Abstract: Although forest ecosystems play an essential role in climate stabilization, current climatic shifts might cause striking changes in their biological productivity, which, in turn, affects the biosphere function of forests. Studies of the relationship between the biomass of trees and stands and hydrothermal indicators (temperature and precipitation) have usually been carried out at local or regional levels. It is still unknown how climate changes affect tree and stand biomass along transcontinental gradients. Therefore, the goals of this study were (a) to test if the law of the limiting factor holds for tree and stand biomass of Picea spp. at the transcontinental level of Eurasia in relation to temperature and precipitation, and (b) to apply the principle of space-for-time substitution to document the use of the derived tree and stand biomass climate-sensitive models for predicting temporal biomass changes. The results revealed that at a tree level spruce aboveground biomass increased with a temperature increase in moisture-rich regions, whereas in moisture–deficient regions it was reduced. Similarly, precipitation reduction at a constant average January temperature caused a reduction in aboveground biomass in warm regions, while in cold regions its increase was revealed. At a stand level, we also revealed an increase in biomass with increased precipitation amount in warm regions. The study suggested that the principle of space-for-time substitution was clearly manifested on biomass quantity of spruce at both individual tree and forest stand levels.
  PubDate: Tue, 23 Aug 2022 00:00:00 GMT
Allometric models for estimating aboveground biomass of young Norway
spruce trees in the Western Carpathians, Slovakia
- Abstract: In the period of climate change, it is necessary to have biomass models for trees of all sizes to make precise estimations of biomass forest stocks to quantify carbon sequestration by forest cover. Therefore, we created allometric models of aboveground biomass in young Norway spruce (Picea abies [L.] Karst.) trees including main components, i.e. stem, branches and needles. The models used 200 sampled trees from 10 sites located in the central part of the Western Carpathians in Slovakia. The models, i.e. allometric regression relations implemented stem base diameter (diameter d0) and/or tree height. Moreover, using the derived allometric relations and a constant annual diameter increment of 10 mm, we calculated quasi-annual aboveground biomass production with regard to diameter d0. While stem had the largest contribution to aboveground biomass, followed by needles and branches, a different situation was revealed for the annual aboveground biomass production with the largest share of needles followed by stem and branches. Finally, we implemented the allometric models in a specific forest stand, where repetitive measurements were performed within 14 consecutive years. The results showed for example nearly 650 kg of the aboveground biomass per 102 m2 at the stand age of 10 years. The new biomass models can be applied to estimate the aboveground biomass stock in Norway spruce dominating stands in the Western Carpathians. Since the models are based on both diameter d0 and tree height a user can choose which variable is more suitable for particular conditions.
  PubDate: Tue, 23 Aug 2022 00:00:00 GMT
Indicators of caesium 137 concentration in forest litter and health status
of pines ( L.) in the Chernobyl zone
- Abstract: We analyse the concentration of caesium-137 (137Cs) in forest litter in relation to forest site conditions. The research was carried out in 2004–2019 in the Krasnogorsk district of the Bryansk region (the Russian Federation). It covered three areas corresponding to the exclusion zone, compulsory resettlement zone, and the zone of residence of the population with the right to resettlement. In all these areas, the concentration of 137Cs in forest litter and the condition of pine stands was studied. We revealed that the forest litter contains more than 90% of 137Cs in all combustible materials. The content of 137Cs in fallen branches, bark, cones, and needles varies from 10 to 15%. More than 50% of the specific activity, which is an indicator of 137Cs content, accounts for needles of pine phytocenoses. In 2019, the best state of pines was recorded for older trees. At the age of 60–80 years, 13% of the studied forest stands were classified as weakened, 87% – as very weakened, and 0% as dying. In the 40–56 age group, dying out and very weakened stands accounted for 50% each, whereas weakened ones were not revealed at all. The interaction between 137Cs and tree age was not identified.
  PubDate: Mon, 09 May 2022 00:00:00 GMT
Bioeconomy perception by students of different study programs –
study from Slovakia
- Abstract: The paper builds on previous international research done by Masiero et al. (2020). It applies on Slovak national level and expands the previous study with different study programs. The societal transformation towards bioeconomy provides an opportunity for changing current economy and societies into more sustainable ones with mitigation of the environmental pressures at hearts. Such societal transition requires involvement of all stakeholders in bio-economy discussion and decision-making process and studying their perceptions of bioeconomy. Amongst all the stakeholders, future generation is particularly important, as it is important to understand bioeconomy perception by the generation of stakeholders that will manage this area in the near future. For that reason, we focus our attention on students of three bioeconomy related areas at the Technical University in Zvolen (forestry studies, wood processing studies and natural resources management studies). We were able to identify significant differences in bioeconomy perception between analyzed categories. The familiarity with the concept is quite high, as more then two thirds have heard about bioeconomy before the survey was conducted. As the main information sources were selected news, university courses and social media. The study program had a greater impact on perceived importance of forests within bioeconomy than the type of study. Overall, students perceive development of forest-based bioeconomy as favouring sustainable forest management.
  PubDate: Mon, 09 May 2022 00:00:00 GMT
Population genetic diversity in and in Southern Urals (Russia): a
comparatively study of adults and progeny in localities with contrast
forest cover
- Abstract: Extensive forest areas decreased and fragmented during anthropogenic development of the zone of broad-leaved forest tree species in Russia. The pedunculate oak (Quercus robur L.) and the European white elm (Ulmus laevis Pall.), important key components of these ecosystems, suffered last few centuries of extreme climate events, attacks of insects and diseases. Using ISSR genetic markers, we compared expected heterozygosity and allelic diversity of these two species in natural and artificial stands, planted and naturally regenerated progeny. Weak differences in the genetic diversity in Q. robur and U. laevis were revealed in areas with different forest cover and participation of the species in a stand composition. Overall, we found that the genetic diversity of parent natural and artificial stands is well reproducing in natural offspring and planted saplings. But the tree species studied express both higher and lower heterozygosity in planted trees in comparison to natural stands.
  PubDate: Mon, 09 May 2022 00:00:00 GMT
Growth of Scots pine ( L.) stands on soils with close bedding of
crystalline parent rocks in Central Polissya, Ukraine
- Abstract: The wide ecological range of Scots pine (Pinus sylvestris L.) demonstrates its ability to adapt to different environments. This study aimed to assess the dynamics of growth and productivity of Scots pine stands growing on soils with crystalline parent rock outcrops. The study area is located in the north of Ukraine in the Central Polissya within 50°15’ and 50°06’ north latitudes and 29°22’ and 29°86’ east longitudes. The base of the geological structure is granite. The depth of the parent rock bedding ranges from 15 to 86 cm. In total, 18 research plots were laid out on soils with crystalline rock outcrops and 18 research plots on sites with deep bedding of crystalline rocks (> 60 cm). To test the difference in stands growth within and outside sites with the crystalline outcrops, we used the Welch t-test. Pine forests on areas with deep bedding of parent rocks are systematically higher than those growing on sites with crystalline outcrops. With an increase of stand age, the difference between specified groups tends to be more significant. Stands growing on sites with and without crystalline rocks outcrops have similar dynamics, however, the latter ones accumulate more growing stock volume due to higher relative stocking, site index, mean diameter, and the number of trees. Our findings indicate the feasibility of establishing Scots pine stands in sites with different depths of the crystalline parent rocks bedding in Central Polissya, Ukraine.
  PubDate: Mon, 09 May 2022 00:00:00 GMT
Radial increment and defoliation of (L.) on sandy soils relate to summer
temperatures and ground water level
- Abstract: The study deals with the analysis of the impact of climate and ground water table level on radial increment and defoliation of Scots pine (Pinus sylvestris L.) growing on sandy soils. The research was performed in the area of the Borska nížina (i.e. Borská Lowland, situated in southwest of Slovakia), where a substantial die-back of pine trees has been observed in the last decade. Increment measurements and defoliation assessment were performed at 150 adult trees of Scots pine growing at three permanent monitoring plots within the international network of ICP Forests during the years 1989–2018. We examined the impact of climatic and hydrological factors on selected features of pine using the methods of correlation analysis and linear mixed models. Statistical analyses confirmed that the annual radial increment of Scots pine significantly depended on the mean air temperature from June to August, and mean ground water level in the mentioned months. These two factors also significantly correlated with crown defoliation. The factors explained 26% and 32% of increment and defoliation variability, respectively. From the long-term perspective, our analyses indicated that the decrease of ground water level by 0.5 m in summer resulted in the increase of defoliation by 10%. The obtained results indicate a further increase of Scots pine die-back on easy-to-dry sandy soils in regions with low precipitation totals, particularly considering the ongoing climate change and its inherent factors.
  PubDate: Mon, 09 May 2022 00:00:00 GMT
Woodland planting on UK pasture land is not economically feasible, yet is
more profitable than some traditional farming practices
- Abstract: Increasing ecosystem service provision is a key strategy of the UK’s ongoing agricultural and environmental policy reforms. Enhancing forest cover by 4%, particularly on the least productive agricultural land, aims to maximise carbon sequestration and achieve net zero by 2050. Multiple factors affect the sequestration potential of afforestation schemes and landowner participation in them, highlighting the need for spatially explicit research. We used the InVEST Carbon Model to investigate the Loddon Catchment, southeast England as a study area. We assessed the carbon sequestration potential and economic feasibility of three broadleaved woodland planting scenarios; arable, pasture, and stakeholder-approved (SA) scenario. We found that over a 50-year time horizon, woodland planting on arable land has the greatest sequestration potential (4.02 tC ha−1 yr−1), compared to planting on pasture land (3.75 tC ha−1 yr−1). When monetising carbon sequestration at current market rates, woodland planting on agricultural land incurs a loss across all farm types. However, when including the value of unpaid labour, lowland pasture farms presently incur a greater loss (−€285.14 ha−1 yr−1) than forestry (−€273.16 ha−1 yr−1), making forestry a more economical land use. Subsidising up to the social value of carbon (€342.23 tC−1) significantly reduces this loss and may make afforestation of pasture land more appealing to farmers. Woodland planting on lowland pasture land would increase forest cover by up to 3.62%. However, due to the influence of farmer attitudes on participation, it is more realistic for afforestation to occur on lowland pasture land in the SA scenario, equating to a 0.74% increase.
  PubDate: Mon, 09 May 2022 00:00:00 GMT
Impact of interest rates on forest management planning based on
multi-criteria decision analysis
- Abstract: The fulfilment of forest functions is significantly affected by forest management, especially the applied harvest regeneration systems. The interest rate can significantly influence forest regeneration planning but was rarely tested. We examined how different interest rates (0%, 0.5%, 1%, 1.5%, 2%, 2.5% and 3%) affect the fulfilment of multiple forest functions and hence, the decision on the optimal forest regeneration system for multiple criteria. The analysis was performed based on the simulation of 450 different harvest-regeneration systems applied to a secondary spruce dominated forest stand and the multi-criteria a posteriori decision analysis. The outputs from the growth simulator were used to quantify the fulfilment of timber production and non-production functions. Three selected indicators (Soil expectation value, Shannon index of species diversity, and height to diameter ratio) were analysed on the base of single-criteria optimisation based on maximising a single indicator and the methods of multi-criteria optimisation of the weighted sum method and Pareto front with the goal to harmonise the fulfilment of three different functions. The results indicated that lower interest rates favoured single tree cutting systems with relatively long rotation cycles (140–160 years), while higher interest rates favoured strip cutting with shorter rotation cycles (90–100 years).
  PubDate: Tue, 08 Mar 2022 00:00:00 GMT
Potential for carbon sequestration and the actual forest structure: the
case of Krasnodar Krai in Russia
- Abstract: This work aims to analyze the age structure of forests in Krasnodar Krai in order to estimate their carbon sequestration potential. The research was conducted during 2015–2020 in 14 forested districts of Krasnodar Krai in the Russian Federation. A database of 96,000 sample plots was used. Aspen occupied the maximum area (20% of trees), while much smaller areas were occupied by linden, birch, pine, and oak (p≥0.05 with aspen). Spruce occupied three times smaller areas compared to aspen (p≤0.05), while maple, elm, ash, and alder had ten times smaller areas (p≤0.01). Among deciduous species by age, mature and overmature stands predominate, while in conifers a young growth prevails (44% – for pines). All pine forests belong to the 1st quality class (91%), for birch and aspen, it is 75–80% of trees (p≤0.05 with the frequency for pine), for spruce – 52% (p≤0.05), and for oak – 10% (p≤0.01). Different tree species make different contributions to carbon sequestration – from 0.3 tons per 1 ha (Alnus glutinosa) to 1.7 tons per ha (Fraxinus excelsior). Taking into account the areas occupied in the forest by different tree species, their contribution will also be different – from 0.5 thousand tons/1 year (F. excelsior) to 290 thousand tons per 1 year (Populus tremula). The total increase in wood stocks and carbon sequestration is mainly due to six forest tree species. The results obtained can be used to assess the potential for carbon sequestration in temperate forests, taking into account their different age structure and tree species composition.
  PubDate: Tue, 08 Mar 2022 00:00:00 GMT
Influence of water supply on cork increment and quality in L.
- Abstract: Cork oak (Quercus suber L.) grows in the Mediterranean basis including Portugal and is the main species producing cork which is used prevailingly in stopper industry. In our paper, cork from Quercus suber L. over three consecutive harvests from a traditional rainfed plot, between 1999 and 2017, and cork from an irrigated plot, harvested in 2017, were studied. We applied two X–ray image analysis technologies – X–ray micro-computed tomography and X–ray microdensitometry. Cork development, related with intern porosity, growth and density was studied with the objective of understanding the cork characteristics evolution over the years and with a different water regime. The outcomes of this study suggested an increase in density and porosity over harvests and a slight decrease of the cork growth. Cork samples from the irrigated plot, compared with cork from the same year of extraction in the rainfed plot, showed higher growth rate and higher porosity. The results demonstrated the contribution of climatic factor of precipitation as well as the silviculture model in cork characteristics, showing the relevance of the present work for the definition of the management practices. These may be determinant for enhancing cork quality and quantity production through silviculture measures. Our findings can be particularly useful for stakeholders especially under the conditions of Portugal in terms of increasing the value of the industrial chain of cork.
  PubDate: Tue, 08 Mar 2022 00:00:00 GMT