56 research outputs found

    Growth and Timber Quality of European Larch Planted in Areas Reclaimed After Coal Mining in Central Poland

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    Understanding the impact of reclamation measures on the quality of timber produced in post-mining areas is crucial for the proper establishment of future forest cultures on such sites. We studied European larch trees (Larix decidua Mill.) grown since 1981 on the external dump of a brown coal mine in Bełchatów (Central Poland). In particular, the effects of stand admixture and the intensity of mineral fertilization, applied in the initial phase of tree growth, on the increments and quality of larch wood were evaluated. Total tree height and stem diameter of 4-meter sections were measured. Qualitative timber classification took into account the share of wood defects, which excluded the timber from a higher quality-dimensional class. Larch trees grown in a monoculture had a better quality of wood compared to larch grown mixed with other species. Fertilization, applied in the initial afforestation period, had only a limited effect on the growth of larch trees. Curvature and knots determined timber quality most significantly. While knots had a decisive importance in larch growing in the monoculture stands, curvature determined wood quality in the admixed larch stands

    Structural differences of cell walls in earlywood and latewood of Pinus sylvestris and their contribution to biomass recalcitrance

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    Scots pine (Pinus sylvestris L.) is an evergreen coniferous tree with wide distribution and good growth performance in a range of habitats. Therefore, wood from P. sylvestris is produced in many managed forests and is frequently used in industry. Despite the importance of pine wood, we still do not fully understand its molecular structure what limits improvements in its processing. One of the basic features leading to variation in wood properties is the presence of earlywood and latewood which form annual growth rings. Here, we characterise biochemical traits that differentiate cell walls of earlywood and latewood in Scots pine. We discover that latewood is less recalcitrant to enzymatic digestion, with galactoglucomannan showing particularly pronounced difference in accessibility. Interestingly, characterisation of lignin reveals a higher proportion of coniferaldehydes in pine latewood and suggests the presence of a different linkage landscape in this wood type. With complementary analysis of wood polysaccharides this enabled us to propose the first detailed molecular model of earlywood and latewood and to conclude that the variation in lignin structure is likely the main determinant of differences in recalcitrance observed between the two wood types in pine. Our discoveries lay the foundation for improvements in industrial processes that use pine wood since we show clear pathways for increasing the efficiency of enzymatic processing of this renewable material. Our work will help guide future breeding of pine trees with desired timber properties and can help link molecular structure of softwood cell walls to function of the different types of xylem in conifers

    Root Biomass and Morphological Characterization of Energy Willow Stumps

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    Energy willow plantations are used in cycles of 20–25 years. After such a period of use, or earlier, plantations should be liquidated. In the case of arable land, liquidation of a plantation also means restoration of the original production properties of the soil. In particular, this means: permanent elimination of the possibility of plant regrowth from the above-ground rootstock and root systems and disintegration and mixing of the above-ground rootstock and root systems. The present authors undertook the task of developing a technology for stump removal on energy willow plantations that would have the advantage of lower energy consumption and execution costs than the technologies used so far. The development of a new machine for the disintegration of the above-ground rootstock and root systems requires recognition of the variability of their morphological parameters and their biomass. For that purpose, a head for planting trees was used to sample rootstocks and extract them, and a number of biometric parameters were determined with the division into thickness fractions. The average biomass of the root system of an energy willow shrub with a butt-end of approx. 10 cm in height was 3.1 kg, of which the butt-end and roots with a diameter greater than 30 mm accounted for more than 73%. The vertical and horizontal range of thick roots, which should be ground during plantation liquidation, is small and amounts to approx. 26 and 29 cm, respectively. This justifies the use of machines that work along strips of land during plantation reclamation

    A preliminary assessment of soil sulphur contamination and vegetations the vicinity of former boreholes on the afforested post-mine site Jeziórko

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    The work aims to assess soil sulfur contamination degree indicating various reclamation efficiencies within microhabitats formed in the “Jeziorko” inoperative boreholes of former sulfur-mining areas which have been reclaimed to forest. Three plot categories have been initially determined in post-mining areas: category D – degraded, i.e. ineffectively reclaimed and unsuccessfully afforested plots, pine stands category (P), and birch stands (B), successfully afforestated. Afterwards, four circular plots were defined within each of the determined categories (4 replications, i.e. a total of 12 plots). For each plot, cover-abundance (according to the Braun-Blanquet scale) and dominant herbaceous vegetation species, tree species and stand density were determined. Height (Ht) and diameter at breast height (DBH) measurements were taken, and a vitality assessment was completed according to the IUFRO classification. Soil samples were collected at each plot from the plots in 5 points at two different depths (0–5 cm and 5–40 cm) and laboratory analysis were prepared. Soil  properties such as texture, pH, electrical  conductivity (EC), hydrolytic acidity (Hh), the contents of soil organic carbon SOC, total nitrogen TN, total sulfur TS, and exchangeable cations (Ca2+, Mg2+, K+, Na+) were determined. Soils from the D plot category were characterised by high sulfur contamination, excess salinity (EC), and strong acidity in top soil. These parameters indicated the completed neutralization had not been performed effectively at certain sites. Pine (P) and birch (B) stands categories showed good growth rates and soil parameters indicating the reclamation treatments  had been completed successfully.The work aims to assess the degree of soil sulphur contamination of the various abandoned reclamation efficiencies, within the microhabitats formed in the “Jeziórko” inoperative boreholes of former sulphur-mining areas. These areas have been reclaimed to the forest. Three plot categories were initially determined in the post-mining areas: category D – degraded, i.e. ineffectively reclaimed and unsuccessfully afforested plots, with low cover-abundance or complete lack of vegetation, pine stands category, category (P) - birch stands and category (B)- successfully afforested. Afterwards, four circular plots were defined within each of the determined categories (4 replications, i.e. a total of 12 plots). For each plot, cover-abundance (according to the Braun-Blanquet scale) and dominant herbaceous vegetation species, tree species and stand density were determined. Height (Ht) and diameter at breast height (DBH) measurements were taken, and a vitality assessment was completed, according to the IUFRO classification. Soil samples were collected at each plot, in 5 points, at two different depths (0–5 cm and 5–40 cm). Finally, laboratory analysis was undertaken. Soil properties such as texture, pH, electrical  conductivity (EC), hydrolytic acidity (Hh), the contents of soil organic carbon SOC, total nitrogen TN, total sulphur TS, and exchangeable cations (Ca2+, Mg2+, K+, Na+) were determined. Soils from the D plot category were characterised by high sulphur contamination, excess salinity (EC) and strong acidity in top soil. These parameters indicated that completed neutralization was not performed effectively at certain sites. Pine (P) and birch (B) stands categories showed good growth rates and soil parameters, indicating that the reclamation treatments were completed successfully

    Design of a Planting Module for an Automatic Device for Forest Regeneration

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    Forest regeneration by means of seedlings grown in container nurseries is usually performed manually with the use of the standard dibble bar or the tube dibble. Manual placement of a large number of seedlings in the soil requires a lot of work. Manual removal of the soil cover and digging the soil in spots with a diameter of 0.4 m requires, under average conditions, about 38 man-hours/ha, while planting with a dibble bar requires about 34 man-hours/ha. Additional work time is needed to carry seedlings over an area that is being afforested. At present, forestry does not have automatic planters that would enable the establishment of forest cultures. The aim of the paper is to present the concept of an autonomous robot and an innovative technology of performing forest regeneration and afforestation of former agricultural and reclaimed areas. The paper also presents the design solutions of the key working unit, which is a universal, openable dibble, cooperating with a three-toothed shaft to prepare a planting spot. The solution proposed enables continuous operation of the machine, i.e. without the need to stop the base vehicle

    Smart strategies for the transition in coal intensive regions

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    The TRACER project supports a number of coal-intensive regions around Europe to design (or re-design) their Research and Innovation (R&I) strategies in order to facilitate their transition towards a sustainable energy system. The TRACER consortium consists of different target regions: South East Bulgaria, North West Bohemia - Czech Republic, Lusatian Lignite District - Germany, Western Macedonia - Greece, Upper Silesian Coalfield - Poland, West Region, Jiu Valley - Romania, Wales – UK, Kolubara - Serbia, Donetsk - Ukraine. Core activities of TRACER include the implementation of an EDP (Entrepreneurial Discovery Process) to mobilise a wide range of stakeholders in each target region to develop an appropriate governance structure and to bring regional stakeholders together to discuss and agree on a shared vision and priorities for coal transition. R&I strategies, industrial roadmaps and decision support tools will be developed jointly with key stakeholders of the TRACER target regions. Further TRACER activities include the identification and analysis of best practice examples of successful and ambitious transition processes in coal intensive regions, a detailed assessment of social, environmental and technological challenges, the elaboration of guidelines on how to mobilise investment as well as dedicated activities to stimulate R&I cooperation among coal intensive regions in Europe and beyond

    A new approach to ticagrelor-based de-escalation of antiplatelet therapy after acute coronary syndrome. A rationale for a randomized, double-blind, placebo-controlled, investigator-initiated, multicenter clinical study

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    © 2021 Via Medica. This article is available in open access under Creative Common Attribution-Non-Commercial-No Derivatives 4.0 International (CC BY-NC-ND 4.0) license. https://creativecommons.org/licenses/by/4.0/The risk of ischemic events gradually decreases after acute coronary syndrome (ACS), reaching a stable level after 1 month, while the risk of bleeding remains steady during the whole period of dual antiplatelet treatment (DAPT). Several de-escalation strategies of antiplatelet treatment aiming to enhance safety of DAPT without depriving it of its efficacy have been evaluated so far. We hypothesized that reduction of the ticagrelor maintenance dose 1 month after ACS and its continuation until 12 months after ACS may improve adherence to antiplatelet treatment due to better tolerability compared with the standard dose of ticagrelor. Moreover, improved safety of treatment and preserved anti-ischemic benefit may also be expected with additional acetylsalicylic acid (ASA) withdrawal. To evaluate these hypotheses, we designed the Evaluating Safety and Efficacy of Two Ticagrelor-based De-escalation Antiplatelet Strategies in Acute Coronary Syndrome — a randomized clinical trial (ELECTRA-SIRIO 2), to assess the influence of ticagrelor dose reduction with or without continuation of ASA versus DAPT with standard dose ticagrelor in reducing clinically relevant bleeding and main-taining anti-ischemic efficacy in ACS patients. The study was designed as a phase III, randomized, multicenter, double-blind, investigator-initiated clinical study with a 12-month follow-up.Peer reviewedFinal Published versio
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