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Evaluation of transformation from even-aged to selection forest by means of Gini index
Get PDFWe used the Gini index for evaluation of the 40-year transformation to selection forests in the Training Forest Enterprise Masaryk Forest Křtiny (Czech Republic). The Gini index values for particular forest stands were compared with the reference values derived from the diameter distribution model curve (type E) by Meyer. From a total of sixteen stands which were evaluated in 2013 (the last periodic inventory), only two stands reached the desired diameter structure. Four other stands reached the desired diameter structure at least once during the transformation period. We recommend the application of Gini index for determination of a success rate of even-aged stand transformation to selection forest.O
Quantification of 'Candidatus Phytoplasma prunorum' in apricot trees exhibiting uneven European stone fruit yellows symptoms
Get PDFThis study focused on quantification of 'Candidatus Phytoplasma prunorum' in apricot trees exhibiting uneven symptoms of European stone fruit yellows. For the research, 17 trees showing early leaf bud break in one part of the crown were selected in winter season, and 13 trees showing leafroll in older part of the shoots and no symptoms in younger part of the same shoots were selected in summer season. Absolute quantification of phytoplasmas was performed by real-time PCR in samples collected from asymptomatic and symptomatic parts. The results showed, that phytoplasma could not be always detected in asymptomatic parts, where 2 out of 17 samples from asymptomatic parts from winter season were negative while in summer season 6 out of 13 samples from asymptomatic parts were negative. Comparison of phytoplasma quantities between symptomatic and asymptomatic plant parts then showed significantly higher quantities in symptomatic parts from samples collected in summer season and no quantity difference in samples collected in winter season.O
Xylogenesis and phloemogenesis of Norway spruce in different ages stands at middle altitudinal zone
Get PDFThis study aimed to determine the influence of the stand age and selected weather conditions on the cambial activity, xylem and phloem formation and their development. For the analysis, microcores were taken weekly from two corresponding stands of Norway spruce (Picea abies (L.) Karst.) with various ages (35- and 106-years-old) during the growing season 2012 in the Czech Republic. Young specimens were characterised by higher cambium activity; however, more considerable variation and imbalance were found there. In old trees, delayed processes during the development of the xylem and phloem at the cell level were proved. The cambium activity started in March till mid-April, and it lasted for 22 weeks in both cases. The commencement of xylogenesis was established in the first half of May. In both investigated stands, the fully lignified ring was observed at the end of October. For the creation of most xylem cells, it was required 124 and 121 days in the young and old stands, respectively. Daily increment of 0.57 (young) and 0.49 (old) cells on average was observed during the active xylem growth. The relationship between air temperature and wood cell formation for both age groups was recorded. The precipitation influenced wood development just in the case of the young trees. Phloem formation was resistant to external influence according to the Pearson correlation coefficient.O
Three-Dimensional Avian Hematopoietic Stem Cell Cultures as a Model for Studying Disease Pathogenesis
Get PDFThree-dimensional (3D) cell culture is attracting increasing attention today because it can mimic tissue environments and provide more realistic results than do conventional cell cultures. On the other hand, very little attention has been given to using 3D cell cultures in the field of avian cell biology. Although mimicking the bone marrow niche is a classic challenge of mammalian stem cell research, experiments have never been conducted in poultry on preparing in vitro the bone marrow niche. It is well known, however, that all diseases cause immunosuppression and target immune cells and their development. Hematopoietic stem cells (HSC) reside in the bone marrow and constitute a source for immune cells of lymphoid and myeloid origins. Disease prevention and control in poultry are facing new challenges, such as greater use of alternative breeding systems and expanding production of eggs and chicken meat in developing countries. Moreover, the COVID-19 pandemic will draw greater attention to the importance of disease management in poultry because poultry constitutes a rich source of zoonotic diseases. For these reasons, and because they will lead to a better understanding of disease pathogenesis, in vivo HSC niches for studying disease pathogenesis can be valuable tools for developing more effective disease prevention, diagnosis, and control. The main goal of this review is to summarize knowledge about avian hematopoietic cells, HSC niches, avian immunosuppressive diseases, and isolation of HSC, and the main part of the review is dedicated to using 3D cell cultures and their possible use for studying disease pathogenesis with practical examples. Therefore, this review can serve as a practical guide to support further preparation of 3D avian HSC niches to study the pathogenesis of avian diseases.O
Urban Parks Hydrological Regime in the Context of Climate Change-A Case Study of Štěpánka Forest Park (Mladá Boleslav, Czech Republic)
Get PDFThe paper presents the results of a case study that was prepared as a basis for decision-making processes in the context of the impacts of global climate change. The article is focused on a very important part of the urban environment, namely urban forests. When taking planning measures in periurban forests, two realities must always be addressed, i.e., adaptation measures to mitigate the effects of climate change on the forest complex in question and its use to mitigate the effects of climate change in its surroundings must both be considered. It is a well-known fact that forest communities (of any kind) are on the one hand affected by the impacts of climate change, but on the other hand are able to mitigate its effects on their surroundings. The case study was of land near the town of Mladá Boleslav. The aim was to analyse the hydrological regime of the Štěpánka Forest Park, nicknamed "the lungs of Mladá Boleslav". Modelling of the runoff coefficient was made for the whole park area, as well as for the part on the left bank of the Klenice River (forested part). The runoff conditions of the site and their subparameters are addressed in the study by comparing the current state with the modelled state after deforestation of the site, e.g., due to drought. As far as the spatial layout of the forest is concerned, it is absolutely essential to maintain an integrated stand on the site with a lower stem cover (fewer individuals per plot) and a lower regeneration period. These aspects of a growing matrix forest stand will ensure its sustainability, in particular the sustainable water management of the trees in the context of lower water reserves in the rhizosphere and the greater ability of younger individuals to adapt to changes in site conditions (replacement of stress-resistant types by resilient types).O
Whole Body Vibrations during Fully Mechanised Logging
Get PDFThis paper seeks to answer the question of whether the magnitude of vibrations affecting the whole body of the harvester operator (WBV) that are generated by the harvester boom is affected by the size of the processed trunk volume, to specify closer, the magnitude of WBVs generated during forest logging, and to localise these WBVs in individual partial operations. For these purposes, the production process, i.e., forest logging, was divided into six partial operations (Searching; Felling; Processing; Unproductive time; Machine movement; Stationary position). WBVs were scanned in the respective partial operations according to standard ISO 2631-1:1997 and the European Directive 2002/44/EC, and then the values were mutually compared. Volumes of processed trunks were recorded, which were then assigned to the given WBV during the respective operations. Research results did not demonstrate a correlation between the size of the transmitted vibrations and the volumes of cut trunks in the partial work operations of Felling and Processing. Neither a difference was found between the individual partial operations with two exceptions: Searching and Felling/Processing and Unproductive time. The research further showed that the average WBV of three partial operations did not meet the daily limit of 0.50 m/s2 permitted by European Directive 2002/44/EC, within a range from 12.20% to 27.02%.O
Corporate social responsibility of public administration through eyes of enterprises
Get PDFThe present paper focuses on corporate social responsibility in public administration. The subject of interest is the South Moravia Region and enterprises seated there. The subject of the present research includes overall awareness of the inquired enterprises about corporate social responsibility and activities of the South Moravian Region Authority related to corporate social responsibility of the institution. The research has brought conclusions testifying a certain level of knowledge of the CSR concept among enterprises, albeit on the basic level only. The awareness of socially responsible activities of the regional authority was very low and therefore further steps of this institution must be considered to improve communication of CSR activities and develop an environment for better cooperation of the public and the private sector in this area. The research was based on secondary data drawn from annual reports of the South Moravian Region Authority and on primary data obtained by questionnaire-based inquiry among 384 enterprises doing business in the South Moravia Region.O
Sustainability assessment & reporting in agriculture sector
No full textSustainability assessment is a mainstream business activity that demonstrates the link between the organization's strategy and commitment to a sustainable global economy. Sustainability indicators describe the environmental, social, economic and governance performance of Small and Medium-sized Businesses/Enterprises (SMB/SME). Unfortunately, their implementations in the Czech Republic show a low level of engagement in sustainability assessment. The paper presents the results of the authors' research in sustainability assessment of SMB/SMEs in the agriculture sector of the Czech Republic. An appropriate set of key performance indicators (KPIs) in four dimensions (economy, environment, social and governance) was developed to suit the SMB/ SMEs sustainability assessment in the agriculture sector. A set of KPIs is proposed to help SMB/SMEs to avoid the barriers of sustainability assessment. These indicators are based mainly on Sustainability Assessment of Food and Agriculture, Global Reporting Initiatives Frameworks and on current research state-of-the-art. They have been created following the analysis of a number of agricultural enterprises over the world, particularly within European countries.O
The effect of slow-release fertilizers on the soil environment of spread windrows in the Krušné Hory Mts.
Get PDFThe current revitalization of forest ecosystems in the Krušne Hory Mts. is carried out through: (i) spreading line windrows, (ii) chemical amelioration. The aim of this research consisted in: (i) assessing basic pedochemical characteristics of spread windrows, (ii) testing the effect of slow-release fertilizers from the Silvamix(R) series and dolomitic limestone on the root ball zone soil five years after application. The results of this study suggest that spread windrows are a suitable environment for forest species: with the only risk being extremely low P concentrations. Our results further show an increase in the amount of soil macrobioelements in the case of Silvamix(R) R and Silvamix(R) Forte, namely P over 125 and 85%; Mg2+ over 84 and 108%; base saturation (BS) over 44 and 40.7%, respectively, compared with a control. Having applied dolomitic limestone, an increase of BS (by 88%), Mg2+ (by 250%) and Ca2+ (by 37%) was observed; there was a reduction in the level of mobile Al3+ (by 25%) compared with the control. Stromfolixyl(R) application did not affect the chemistry of the soil environment.O
Motherhood Penalty in the Czech Republic: Its Evolution and Sources
Get PDFPro odhad výše mateřské sankce používáme údaje EU SILC pro Českou republiku v období 2006-2017. Zjistili jsme, že upravená mateřská sankce činí 11-15 % v období 2006 - 2008. V této době se Česká republika jevila jako srovnatelná se zeměmi jako je Německo a Velká Británie. Po roce 2009 mateřská sankce mizí a Česká republika se řadí do stejné skupiny se skandinávskými zeměmi, Francií a Belgií. Navzdory tomu, však stále existuje mnoho překážek pro participaci matek na trhu práce, což se promítá hlavně do mzdových sankcí prostřednictvím nižších zkušeností a intenzity práce. Studie podporuje také další důkazy z mezinárodního srovnání, kdy mateřská sankce je většinou fenoménem středně vzdělaných, vdaných žen, žijících mimo velká města, zaměstnaných v soukromém průmyslu a majících více než jedno dítě.We use EU SILC data for the Czech Republic to estimate the size of the motherhood penalty for the period 2006-2017. We find out that adjusted motherhood penalty amounts to 11-15% in the period 2006-2008. At that time, the Czech Republic appeared to be comparable to countries such as Germany and the UK. However, the motherhood penalty effectively disappears after 2009 and the Czech Republic is now placed in the same group with Scandinavian countries, France and Belgium. Despite that, there are still many obstacles for mothers to increase their labour market participation, which translate mainly into wage penalties via the experience and labour intensity channels. The study also supports other general evidence from cross-country motherhood penalty comparisons, motherhood penalty being mostly a phenomenon of middle-educated, married women located outside large cities, employed in private industry and having more than one child.O