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Results of Ribes breeding at the National University of Life and Environmental Sciences of Ukraine
2020
Mezhenskyj, V., National Univ. of Life and Environmental Sciences of Ukraine, Kiev (Ukraine) | Kondratenko, T., National Univ. of Life and Environmental Sciences of Ukraine, Kiev (Ukraine) | Mazur, B., National Univ. of Life and Environmental Sciences of Ukraine, Kiev (Ukraine) | Shevchuk, N., National Univ. of Life and Environmental Sciences of Ukraine, Kiev (Ukraine) | Andrusyk, Yu., National Univ. of Life and Environmental Sciences of Ukraine, Kiev (Ukraine) | Kuzminets, O., National Univ. of Life and Environmental Sciences of Ukraine, Kiev (Ukraine)
Breeding work on Ribes species has been started at the National University of Life and Environmental Sciences of Ukraine in Kyiv since 1984 by Petro Sherenhovyj. The breeding programme has been focused on fruit quality, yield, resistance to diseases and pests, as well as on adaptive responses to environmental conditions. As a result of the long-term work, 18 new cultivars were included in the State Register of Plant Varieties of Ukraine in 1999– 2016. The aim of this paper is to describe these varieties: 10 blackcurrant (‘Dochka Vorskly’, ‘Hovtva’, ‘Pam`yati Leonida Mykhalevskoho’, ‘Universytetska’, ‘Aspirantska’, ‘Didorivska’, ‘Poltava 584’, ‘Petrivska’, ‘Yuvileina Sherenhovoho’, and ‘Leleka’), 5 redcurrant (‘Kyianochka’, ‘Poliana Holosiivska’, ‘Buzhanska’, ‘Malva’, and ‘Olha’), 1 whitecurrant (‘Lebidka’), and 2 gooseberry (‘Vasylko’, and ‘Tikych’). The varieties described give farmers and scientists the best knowledge about these cultivars with good level of commercial traits, suitable for dissemination in Ukraine.
اظهر المزيد [+] اقل [-]Influence of drainage reconstruction on radial increment of conifers: case study
2020
Jansone, B., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia);Latvian State Forest Research Inst. Silava, Salaspils (Latvia) | Sisenis, L., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia) | Pilvere, I., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia) | Vinters, M., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia) | Bickovskis, K., Latvian State Forest Research Inst. Silava, Salaspils (Latvia)
Drainage ensures flow of water and access of oxygen to the roots of the trees. Therefore, melioration systems have been established in a third of the forest area of Latvia, and for the most part highly productive stands can be observed in these areas. Water flow in these systems is often stopped by beaver dams. The aim of our case study was to assess the impact of ditch reconstruction on the increment of the coniferous trees. Increment cores were collected from 169 trees at a distance up to 45 m from the ditch in the drainage system that was reconstructed 8 years prior. Drainage system reconstruction reversed the trend of declining radial increment for both Scots pine and Norway spruce; however, the influence of this measure over an 8 year period was statistically significant, notable (55%) and positive only for Norway spruce, growing closest to the edge of the ditch. Other growth limiting factors need to be considered and tackled to ensure the highest effect of the investment in drainage system reconstruction, including choice of the tree species, stand density, age, and availability of nutrients.
اظهر المزيد [+] اقل [-]Evaluation of compliance of existing forest machine information systems for the implementation of the standard StanForD 2010
2020
Strubergs, A., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia) | Lazdins, A., Latvian State Forest Research Inst. Silava, Salaspils (Latvia) | Sisenis, L., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia)
The aim of the study is to clarify the compliance of machinery information systems used by Latvian logging service providers with the requirements of the Forest Machine Data and Communications Standard StanForD 2010. For determining the number of logging machines and structure registered in Latvia, data from the State Technical Control Agency of Latvia (VTUA) has been used. This dataset includes 2094 registered machinery units from which 1663 units recorded as harvesters and forwarders are distributed for data processing. Using the national AS Latvian State Forests (LSF) database, where 541 machinery units have been recorded, of which 239 harvesters and 302 forwarders, it is determined what and how many machines already use the standard StanForD 2010, how many machines can implement it and which machines are not suitable for the implementation of StanForD 2010. The study showed that the VTUA register does not fully reflect the true quantity of harvesting machines in Latvia and does not provide information about the use of machines. The LSF data provide reliable information on the possibilities of using StanForD 2010 in harvesters in national forests. From the harvesters working in the country’s forests, 52% of the machines use the StanForD 2010 standard. Work should be continued to clarify the possible use of the standard in the machines working in private forests. Similarly, work should be continued with dealers of harvesting machines to identify models for which it is possible to adjust the StanForD 2010 standard and what the cost of adapting the indicative information systems is.
اظهر المزيد [+] اقل [-]Chemical properties of needles as an indicator of nutrient status of fertilized coniferous stands
2020
Karklina, I., Latvian State Forest Research Inst. Silava, Salaspils (Latvia);University of Latvia, Riga (Latvia) | Zvaigzne, Z.A., Latvian State Forest Research Inst. Silava, Salaspils (Latvia) | Stola, J., Latvian State Forest Research Inst. Silava, Salaspils, Latvia
Enhanced forest growth may respond to demand of woody resources and contribute to the climate change mitigation. Forest soil treatment with fertilizers, as well as drainage and thinning enhance forest growth. The analysis of needles is an established method in forest science to identify the nutrient status in the forest stand and need for forest soil enrichment with fertilizers. The aim of this research is to estimate the efficiency of forest soil enrichment with wood ash and ammonium nitrate in order to eliminate nutrient deficiency in forest stands. Forest soil was enriched with wood ash fertilizer or ammonium nitrate in 2016–2017. The current year needles were collected from fertilized and control plots, from three trees in each plot. The samples were collected in the period 2018–2019. Total nitrogen (g kgE−1), calcium (g kgE−1), magnesium (g kgE−1), and potassium (g kgE−1) were analysed in the collected samples. The chemical properties of collected needles were compared at the individual object level to estimate the impact of fertilizer on forest stand. A statistically significant increase in the concentrations of potassium and phosphorus was detected in some plots treated with wood ash and ammonium nitrate. In addition, a correlation analysis conducted between the variables of chemical properties of needles and soil showed few significant correlations between nutrient content in needles and in soil samples.
اظهر المزيد [+] اقل [-]Composition of extracts isolated from black alder bark by microwave assisted water extraction
2020
Arshanitsa, A., Latvian State Inst. of Wood Chemistry, Riga (Latvia) | Ponomarenko, J., Latvian State Inst. of Wood Chemistry, Riga (Latvia) | Lauberts, M., Latvian State Inst. of Wood Chemistry, Riga (Latvia) | Jurkjane, V., Latvian State Inst. of Wood Chemistry, Riga (Latvia)
The composition of extracts isolated from black alder bark by ‘green’ microwave assisted water extraction in the temperature range of 70–150 °C was studied using the wet chemistry Folin-Ciocalteu method and Py-GC-MS/FID. The composition data were compared with those of the extracts obtained at the same temperature by accelerated solvent extraction (ASE) of bark. It was shown that microwave assisted extraction, compared with ASE, resulted in more significant transition of major cell wall components, including hemicelluloses and phenolics of lignin origination, into the solution. Depending on the microwave assisted extraction regimes, products with different portion of major cell wall components and secondary phenolic metabolites can be isolated that enlarge the possibilities of products valorisation. Thus, a significant promotion of secondary phenolic metabolites’ transition into extracts as a result of microwave extraction was observed at 70 °C. At that time the relative portion of carbohydrates in extracts was increased at high temperature extraction, combining dynamic and isothermal microwave heating. Water extraction of black alder bark in a microwave extractor revealed 25–50% lower specific energy consumption and 1.8–2.6 times higher productivity in comparison with the conventional extraction, that is beneficial in view of the upscale and practical application of this innovative biomass processing.
اظهر المزيد [+] اقل [-]α-amylase activity in freeze-dried and spray-dried honey
2020
Keke, A., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia) | Cinkmanis, I., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia)
Honey is a naturally supersaturated sugar solution, which tends to crystallize. The crystallization of honey can lead to unwanted fermentation that can have a negative impact to honey quality. The production of honey powder could be an alternative method to prevent honey from fermentation. Honey powder could be used as alternative substitute to liquid honey that would allow to use this product more widely in the food industry. α-amylase activity is one of the most important parameters to evaluate the quality of honey. The aim of this study was to investigate the effect of freeze-drying and spray-drying on honey α-amylase activity. Detection of α-amylase activity was carried out by spectrophotometric method. High-performance liquid chromatography was used to determine the content of hydroxymethylfurfural in the powders. The obtained results showed that both drying methods had a negative impact to the enzyme activity in the samples. The lowest activity of α-amylase (8.3 DN) was measured in the spray-dried honey powder. Concentration of hydroxymethylfurfural (HMF) in the powders did not exceed required concentration 40 mg kgE−1.
اظهر المزيد [+] اقل [-]Development of ecosystem service opportunities in the Nemunas Delta in the context of global climate change
2020
Pilipavicius, V., Vytautas Magnus Univ., Kaunas (Lithuania) | Zukovskis, J., Klaipeda Univ. (Lithuania)
The second half of the 20th century brought to light the consequences of human activity, when Humanity was confronted with demiurgical complexes and realized that the planet Earth was not only nature, but a complex system that today could no longer be operated by traditional methods and logic. While until the middle of the 20th century man used natural resources only to meet his needs, the 21st century poses new challenges for mankind to manage the consequences of human activities and to use them rationally and sustainably. The paper presents a study aimed at assessing the potential of ecosystem services development in the Nemunas Delta and anticipating their development directions. As a result of the research, the possible development directions of the Elderships were presented. It was done in two scenarios. The research was carried out in six municipality subdivisions (elderships) of the Nemunas Delta area in the framework of the Lithuanian Science Council project ‘Interaction of ecosystem services and human activities in the context of climate change’. Preparation of this paper was supported by funding from European Social Fund (project No 09.3.3-LMT-K-712-01-0178) under the grant agreement with the Research Council of Lithuania (LMTLT).
اظهر المزيد [+] اقل [-]Resilience in agriculture: how can CAP direct payments impact it?
2020
Zickiene, A., Lithuanian Inst. of Agrarian Economics, Vilnius (Lithuania)
The increasing frequency and magnitude of adverse meteorological events together with the growing uncertainty in the upcoming future pose more and more challenges to agriculture. Therefore, the future sustainability of agriculture will increasingly depend on its resilience, i.e. the capacity to withstand various perturbations and to recover from them. The direct payment (DP) system of the EU Common agricultural policy (CAP) is the most financed EU support scheme for agriculture; however, research on its impact on the important phenomena of resilience is scarce and fragmented. In order to fill this gap, this paper offers an extensive overview of literature and a summarized list of factors that are mentioned most often as potentially influencing the agricultural resilience. Based on this, the possible impact of DP on agricultural resilience was analysed. In this paper, it is argued that this impact is transferred mostly through changing farms’ financial capabilities as well as farmers’ attitudes and behaviour, and is both positive and negative. Such phenomena as low crop insurance uptake and decrease in productivity may be due to the overcrowding effects of direct payments. These hypotheses are being tested in a survey, conducted in the meantime.
اظهر المزيد [+] اقل [-]Challenges in human resource management in the culture industry in Latvia
2020
Bethere, S., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia) | Licite-Kurbe, L., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia)
The culture industry and its human resources have been little researched in Latvia, yet research on the culture industry is important, because the industry makes a significant contribution to economic growth by promoting employment and the development of competitive regions. The culture industry encompasses libraries, folk art, theatre, music, museums, the creative industry and other sub-industries, yet in recent years those working in all the culture subindustries faced various challenges, including: a low remuneration and insufficient monetary and non-monetary bonuses, resulting in lower job satisfaction and a high personnel turnover. Accordingly, the aim of the research is to develop recommendations for hiring and retaining human resources by examining challenges in managing human resources in the culture industry. The authors conducted a survey among the personnel of the Board of Culture of Jelgava municipality. The survey found that the main challenges faced by the administration of the Board of Culture were an uncompetitive remuneration, the aging of the personnel and generational change as well as inefficient and insufficient motivation for working. The research has developed two scenarios for recruiting: ‘promotion of creativity and non-monetary motivation’ that aim to publicly appreciate human resources, so that they would feel important and significant as well as facilitate creativity, innovation and collective solidarity, while for the purpose of retaining human resources in a long-term and decreasing their turnover, the second scenario ‘competitive remuneration and the differentiation by position category’ aims to gradually raise the remuneration and differentiate it for all categories of personnel.
اظهر المزيد [+] اقل [-]Company capital structure’s theoretical framework: historical assessment and trends in the 21st century
2020
Pilvere-Javorska, A., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia) | Pilvere, I., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia) | Riva, B., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia)
Company capital is essential in running business and creating value added for the stakeholders, including economy. How the view on company’s capital structure has evolved from theoretical perspective in the 20th century is needed to be assessed, in order to determine what concepts and theories, if any are relevant in the 21st century. Many theories have competed their way and transformed during the 20th century, while some, i.e. trade-off, signalling and stakeholder theories are still relevant in the 21st century. There are also new trends in the 21st century, new terms and quests shifting from determining and analysing optimal company’s capital structure to sustainable finance, taxonomy and also sustainability in capital structure. Therefore, the aim of this research: to establish existing main theories impacting and analysing company’s capital structure and to examine the theoretical shift of the theories based on the needs in the 21st century. Authors defined company’s capital structure and determined that during the years 1989–2020, number of research publications has grown significantly, thus validating the need to reassess theoretical background of capital structure theories in the 20th century, as well as to help to determine the trends still relative and emerging from the theoretical and practical aspects to company’s capital structure in the 21st century.
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