2957 research outputs found
Sort by
Tractors and skidders in forestry
Get PDFThe publication Tractors and skidders in forestry discusses basic energy devices in forestry for mechanised ground-based timber skidding. It also focuses on appropriate work procedures and work safety with these machines. The publication is divided into six chapters: Classification of energy devices, Basic quantities of tractor mechanics, Basics of terramechanics, Basic principles of hydraulic mechanisms, Mechanized ground-based timber skidding and Occupational safety and health. The publication is intended for the professional public and students of high schools and universities.Published Versio
The spatial dependence of base saturation on forest soil grain and chemical composition seen through individual and typological divisions
Get PDFPůdní bazická saturace (BS) je fyzikálně-chemickou vlastností využívanou při klasifikaci suchozemských ekosystémů. V této studii jsme se zaměřili na porovnání půdní BS a prostorově souvisejících fyzikálních a chemických vlastností mezi individuálním a typologickým členěním lesů. Závislost BS na fyzikálních a ostatních chemických vlastnostech lesních půd byla zjištěna pomocí geograficky vážené regrese. Půdní vlastnosti stejně jako charakteristiky regrese byly rozděleny podél pedogeografických regionů a asociací. Podobnosti půdních vlastností mezi individuálním a typologickým členěním byly srovnány pomocí kvantilů z prostorových modelů dvouvýběrovými t-testy a jednoduchými lineárními regresemi. Nezávisle proměnné vystihly 26-91 % rozptylu BS, kdy průměrné geograficky vážené koeficienty determinace (R2) mezi pedoregiony kolísaly v intervalu 0,40-0,86 a mezi půdními asociacemi v intervalu 0,55-0,83. Mezi srovnávanými individuálními a typologickými členěními převažovaly málo významné (p < 0,5) rozdíly BS. Pouze práškový písek, pH a P2O5 ovlivnily bazickou saturaci lesních půd neopakovatelně mezi pedogeografickými regiony.Soil base saturation is a physicochemical property used for classifying terrestrial ecosystems. In this study, we focused on a comparison of soil base saturation and spatially related soil physical and chemical properties between individual and typological forest divisions. The dependence of soil base saturation on physical and other chemical properties was obtained through geographically weighted regression. Both soil properties and regression characteristics were divided along soil regions and associations. The similarities of soil properties between individual and typological soil division systems were assessed through quantiles from spatial models by two-tailed t-tests and simple linear regressions. Independent variables characterized 26MINUS SIGN 91% of soil base saturation variance, with mean geographically weighted determination coefficients (R2) between soil regions varying from 0.40 to 0.86, and between soil associations from 0.55 to 0.83. Low significant (p < 0.5) differences in distributions of soil base saturation predominated in both individual and typological systems. Only loam content, P2O5 and pH showed unique regional effects on soil base saturation.O
Evaluation of variability of the content of alpha and beta acids in Czech bittering hop varieties (Humulus lupulus L.)
Get PDFCzech bitter varieties were evaluated between 2010 and 2022. Hop varieties displayed an average content of alpha acids between 10.24% w/w (Agnus) and 13.73% w/w (Gaia). Variability below 15%, proved good stability of alpha acids content in all tested bittering hops. All varieties showed a decrease in the content of alpha acids over a period of 13 years of hop cultivation. The highest content of beta acids was determined in Gaia (7.30% w/w). In contrast, the lowest content of beta acids was found in Rubín (3.73% w/w). The new bitter genotypes Uran and 5304 had an average alpha acid content of 11.56% w/w and 10.82% w/w, respectively. Uran showed an average beta acid content of 5.47% w/w and for the genotype 5304 it was 3.61% w/w. In terms of the alpha/beta acids ratio, the hop varieties can be divided into three groups. The first group included the varieties with an alpha/beta acids ratio below 2, i.e. Vital, Boomerang and Gaia. While Agnus and Uran displayed an alpha/beta ratio slightly above 2. The highest alpha/beta ratio above 3 was found in Rubín and the 5303 genotype.O
Aluminum Oxide and Zinc Oxide Induced Nanotoxicity in Rat Brain, Heart, and Lung
Get PDFNanomaterials or nanoparticles are commonly used in the cosmetics, medicine, and food industries. Many researchers studied the possible side effects of several nanoparticles including aluminum oxide (Al2O3-nps) and zinc oxide nanoparticles (ZnO-nps). Although, there is limited information available on their direct or side effects, especially on the brain, heart, and lung functions. This study aimed to investigate the neurotoxicity, cardiotoxicity, and lung toxicity induced by Al2O3-nps and ZnO-nps or in combination via studying changes in gene expression, alteration in cytokine production, tumor suppressor protein p53, neurotransmitters, oxidative stress, and the histological and morphological changes. Obtained results showed that Al2O3-nps, ZnO-nps and their combination cause an increase in 8-hydroxy-2'-deoxyguanosine (8-OHdG), cytokines, p53, oxidative stress, creatine kinase, norepinephrine, acetylcholine (ACh), and lipid profile. Moreover, significant changes in the gene expression of mitochondrial transcription factor-A (mtTFA) and peroxisome proliferator activator receptorgamma- coactivator-1α (PGC-1α) were also noted. On the other hand, a significant decrease in the levels of antioxidant enzymes, total antioxidant capacity (TAC), reduced glutathione (GSH), paraoxonase 1 (PON1), neurotransmitters (dopamine - DA, and serotonin - SER), and the activity of acetylcholine esterase (AChE) in the brain, heart, and lung were found. Additionally, these results were confirmed by histological examinations. The present study revealed that the toxic effects were more when these nanoparticle doses are used in combination. Thus, Al2O3-nps and ZnO-nps may behave as neurotoxic, cardiotoxic, and lung toxic, especially upon exposure to rats in combination.O
Environmental protection and sustainable tourism of cross-border national parks in Kosovo, Montenegro and Albania: contingent valuation method
No full textThe border triangle between Kosovo, Montenegro, and Albania, comprising national parks in the Western Balkans, is experiencing a surge in mountain tourism, posing environmental conservation and sustainable tourism challenges. Concerns about preserving these parks have prompted an investigation into visitors' willingness to support sustainable practices financially. This study used willingness-to-pay (WTP) methods to examine visitor preferences based on demographic factors such as age, country of origin, and education. The Contingent Valuation Method (CVM) was employed to determine the monetary value visitors are willing to contribute to these parks. Results indicate that most (80%) visitors are willing to financially support improving services and sustainable tourism practices, with willingness to pay ranging from 1 to 4 EUR. However, willingness to pay tends to decrease with age, and visitors from Kosovo and Albania exhibit higher willingness levels than those from Montenegro. Interestingly, visitors with primary education show a negative inclination towards WTP. These findings offer valuable insights for stakeholders crafting sustainable tourism strategies in the Western Balkan countries.Published Versio
Effect of exogenous essential oil treatments on the storage behaviour of apricot fruit harvested at different altitudes
Get PDFDue to the short shelf life of fresh apricots, special postharvest preservation techniques and practices are necessary to avoid significant economic losses. The purpose of the current study is to bring to light an approach that can be used to extend the storage life of apricot fruits treated with essential oils (EOs) (peppermint, thyme and carob EO) and examine the effects of two altitudes (1000 m and 1200 m) on the organic acid levels and respiration rate of apricot fruit during long-term storage. The results show that growing apricots at high altitudes increases the level of organic acids in the fruit, improving its quality and extending its postharvest life. Additionally, treating apricots with EOs postharvest slows down the respiration rate, reducing the consumption of organic acids during storage compared to the untreated fruit. The organic acid content was significantly higher in 'Kabaaşı' than in 'Hacıhaliloğlu', and fruit harvested at 1200 m had significantly higher levels of organic acid than the fruit harvested at 1000 m. During storage, the highest organic acid content and the lowest respiration rate were observed in the fruit of both cultivars treated with peppermint, carob, and thyme oil, as compared to control fruit, respectively. To summarize, the use of EOs as postharvest treatment for apricot is recommended for maintaining the quality of the fruit during extended storage.O
A representative dataset on Czech and Slovak pre-Russia-Ukraine-war attitudes to the West and to the Russian Federation
Get PDFThis article presents a comprehensive dataset and its associated data collection methodology aimed at understanding public opinion and attitudes across diverse socio-political dimensions in Czechia and Slovakia. The dataset covers a wide array of variables, including socio-demographic variables, media consumption patterns, scales measuring attitudes and ideology, evaluations of political statements, and reactions to political billboards. The dataset is structured into folders containing raw data, metadata, research samples, analyses, and visual stimuli used in the study. The raw data files encompass original survey responses received from participants, while the metadata provides essential details about variables, their coding, scaling, and question formulation. The survey contains data from more than 1200 Czech and Slovak participants. The samples are representative by gender, age, education level, region, and place of residence size. Researchers utilizing this dataset have the opportunity to explore public opinion dynamics, ideological tendencies, and responses to political stimuli. The dataset's extensive and multifaceted nature offers a valuable resource for various analyses, allowing researchers to delve into factors shaping political orientations, public sentiment towards specific political narratives, and the impact of visual stimuli on political perceptions. Moreover, the dataset's inclusion of both Czechia and Slovakia provides a comparative dimension, enabling cross-country analyses and insights into potential socio-political divergences or convergences within the region. Its accessibility and comprehensiveness make it a valuable asset for a wide range of research endeavors across political science, sociology, psychology, and related disciplines.O
Assessment of carbon sequestration as affected by different management practices using the RothC model
Get PDFLong-term field experiments provide a valuable dataset for predicting changes in soil organic carbon (SOC) stocks in different agricultural systems. The RothC-26.3 model was used to simulate changes in SOC in the monoculture of spring barley (Hordeum vulgare L.) and the Norfolk crop rotation during 1972-2100. The potential of the Gleyic Fluvisol Clayic to sequester organic carbon was investigated. The studied soil was heavily textured, with medium organic carbon content. Four management scenarios in the monoculture and six management scenarios in the Norfolk crop rotation were evaluated. Three different global climate models (MPI, MRI, CMSS) representing the uncertainty of future climate conditions were used. Results showed that carbon stocks were mainly influenced by plant residue inputs and exogenous organic materials application. The projection showed trends of carbon stocks decreasing in the case of monoculture management. Results also documented that management scenario D with straw incorporation and intercrops represented sustainability and carbon stock increase during all modelled climate scenarios. The SOC stock at the end of the century was approximately 66 t/ha. This represents a moderate sequestration of SOC of approximately 0.09 t/ha/year.O
Invasive bark beetle Dryocoetes himalayensis (Coleoptera: Curculionidae: Scolytinae) – A threat for walnut trees (Juglans spp.) in Europe?
Get PDFAs walnut trees (Juglans spp.) are of high economic importance, considerable attention has been given to invasive pests of these trees in Europe. In 2016, Dryocoetes himalayensis Strohmeyer, 1908, an alien bark beetle originating from the Himalayas region of India, already present in several European countries, was confirmed to have attacked walnut trees in the Czech Republic. Within the present study, we (i) surveyed the current distribution of D. himalayensis in the Czech Republic, (ii) examined D. himalayensis phenology by rearing it in trap logs, and (iii) investigated tree level habitat preferences of the species in two study stands with 180 black walnut (Juglans nigra L.) trees and 66 common walnut (Juglans regia L.) trees sampled. The present study documented the species to be relatively widespread in some warmer lowland regions of the Czech Republic (42 localities found) and to reach high abundance locally. Almost 15 thousand D. himalayensis individuals reared from the trap logs showed the species emerging throughout the whole vegetation period with a distinctive peak in June. Even though the species is able to develop in thin stems (diameter <5 cm), it is most numerous in thicker trunk bases and also preferably attacks trees of higher diameters. The species preferred common walnut trees (its native host) with decreased vitality. In contrast, black walnut trees (North American species) were attacked regardless of their vitality, but the vitality of occupied trees successively decreased. Based on our results, D. himalayensis should be assumed as a considerable pest of walnut trees (particularly black walnuts), which might become of significant importance in its European invasive range in the future, and thus substantial attention should be given to it.OA-hybri
Intervention analysis of COVID-19 pandemic impact on timber price in selected markets
Get PDFUsing intervention analysis and time series of roundwood prices from ten European and North American countries, we analyzed the impact of the COVID-19 pandemic on the movement of timber prices. The study material consists of forty-six quarterly time series prices of logs and pulp, both softwood and hardwood, covering the period 2005-2022. During the Covid-19 pandemic period (2020:Q1-2020:Q4), softwood log prices mostly underwent declines, with the changes being the largest in Slovakia (MINUS SIGN 35%), the Czech Republic (MINUS SIGN 24%) and Austria (MINUS SIGN 24%), slightly smaller in the United States (MINUS SIGN 19%), Poland (MINUS SIGN 17%), Slovenia (MINUS SIGN 12%) and Germany (MINUS SIGN 11%) while no significant price changes were recorded in Finland and Sweden. In Canada and the United States, sharp price declines occurred earlier (2020:Q1 and 2020:Q2, respectively), while in Europe, significant price declines occurred later and lasted longer. In the post-pandemic COVID-19 period, prices increased, but in most cases, the shift was not statistically significant compared to the pre-pandemic period. Softwood pulp prices were subject to much less change, with a significant increase only in Slovakia and Poland. In contrast, no significant changes were observed in the price of both log and pulpwood hardwood during the COVID-19 pandemic.OA-hybri