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Factors affecting the competitiveness of a higher education institution: systematic literature overview
2018
Supe, L., Riga Technical Univ. (Latvia) | Zeps, A., Riga Technical Univ. (Latvia) | Jurgelane, I., Riga Technical Univ. (Latvia) | Ribickis, L., Riga Technical Univ. (Latvia)
The aim of the study is using systematic literature analysis method – literature overview – identify the factors, which affect the competitiveness of a higher education institution in the conditions of globalization. Qualitative methods, as well as systematic literature analysis method – literature overview have been used in the study. More than 6000 scientific articles were considered to choose 20 full text articles for in-depth analysis. Main conclusions and results – the systematic literature analysis method – literature overview is a convenient tool for systematizing, selecting and collecting information about the research subject, using author’s articles, which have already gathered key information from a number of researchers of a specific topic together; the competitiveness of higher education institution is influenced by the internal factors that are formed by the internal environment of the higher education institution and external factors that are formed by the external micro-environment and macro-environment influenced by the state policy; an analysis of the internal and external factors of an institution is important in order to create competitive advantages in a higher education institution.
Показать больше [+] Меньше [-]Procedures for the control and quality assurance of e-learning materials
2018
Kazaine, I., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia) | Arhipova, I., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia)
With the growing demand for e-learning, as well with the striving for excellence, everyone worldwide is encouraged to improve and ensure the quality of e-learning. Quality assurance requires a supportive environment. The purpose of this paper is to propose procedures for evaluating and controlling the quality of e-learning materials. The article reflects on the approach, which is often mentioned in the field of quality assurance, procedures that characterize the processes, helps to sort them, track their progress sequence and identify those responsible. Clearly, the quality of online learning has many dimensions, but this article deals only with the part that relates to the quality of e-learning materials. In January 2018, experts from European Distance Education Secondary School, Riga Distance Education Secondary School and Riga 1st Distance Education Secondary School were interviewed. The questionnaire included questions about the quality assessment of the study materials. Based on the findings of scientific research literature and taking into account the good practice, procedures for the quality control of electronic learning materials were created. The article offers four procedures that include the use of a web-based checklist developed by the author. Activities of procedures can be divided into areas of responsibility that deal with developers of the material, methodological commission, material evaluators and IT administrator. Distance learning program implementers can use the proposed procedures in the process of making and monitoring electronic learning materials. In addition, the checklist helps to identify important conditions and requirements that affect the quality of the study material.
Показать больше [+] Меньше [-]Recent land cover changes in Latvia
2018
Baders, E., Latvian State Forest Research Inst. Silava, Salaspils (Latvia) | Lukins, M., Latvian State Forest Research Inst. Silava, Salaspils (Latvia) | Zarins, J., Latvian State Forest Research Inst. Silava, Salaspils (Latvia) | Krisans, O., Latvian State Forest Research Inst. Silava, Salaspils (Latvia) | Jansons, A., Latvian State Forest Research Inst. Silava, Salaspils (Latvia) | Jansons, J., Latvian State Forest Research Inst. Silava, Salaspils (Latvia)
Increase in use of biomass as renewable source of energy in Europe is tightly linked to the policies aimed at mitigation of climate changes i.e. reductions of greenhouse gas emissions. Both for assessment of the carbon sequestration and emissions as well as for assessment of potential amounts of biomass for renewable energy, information of land cover dynamics are essential. Therefore, the aim of our study was to improve accuracy of estimates of the land use changes in the time period between 1990 and 2014. Land use categories were determined in accordance to UNFCCC: wetland, cropland (arable land, bare field), forest, grassland, settlements (urban/suburban area), and other land. Combination of data from National forest inventory (NFI) sample plots and analysis of Landsat images were used. For the classification based on Landsat images vegetation index (NDVI) was estimated and linked to known information on the land use type from NFI sample plot data. In the analysed period, the most significant changes were found for forest lands – the total area of forest land during the last two decades had increased by 1% (64.5 thousand ha). Similar increase (1.2%) was observed also in the area of cropland. Both of these tendencies were primarily the result of marginal field area reduction (by 2.6%). Increase in forest area and thus annual increment has led to an increase in above-ground biomass by 10.2 m**3 haE-1.
Показать больше [+] Меньше [-]Forest regeneration quality – factors affecting first year survival of planted trees
2018
Dumins, K., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia);Latvian State Forest Research Inst. Silava, Salaspils (Latvia) | Lazdina, D., Latvian State Forest Research Inst. Silava, Salaspils (Latvia)
The early stage of forestry is crucial for successful and sustainable forest management. One third of the reforested forest in Latvia is regenerated by planting with different kinds of tree seedlings. The success of forest regeneration by planting depends on correctly prepared soil and choice of the right seedling material. The aim of this study was to evaluate the impact of different soil preparation methods and used type of seedlings on tree survival and growth rate after the first growing season. For this study six young stand sites located in the north-west and central part of Latvia were established in three forest types and in each site soil was prepared in furrows by disc trenching, in mound and left untreated. Reforestation was conducted in the spring of 2017 with four tree species Picea abies, Pinus sylvestris, Alnus glutinosa and Betula pendula and three seedling types were used, bare roots, containerized and improved root system. The evaluation of survival and measure of annual increment was conducted at the end of the first growing season in the autumn of 2017. Results showed that overall the highest seedling survival rate provided soil prepared in mound (90%), and seedlings with improved root system, though the lowest survival rate was observed for bare root seedlings. Containerized seedlings have a higher proportional increment if compared to bare root and improved root system seedlings, but differences are not significant yet (p is greater than 0.05). In conclusion, the survival rate of outplanted seedlings differs by chosen stocktype and soil preparation method used in forest regeneration and for various tree species impact of chosen stock type on survival rate differs.
Показать больше [+] Меньше [-]Characteristic of browsing damages in Norway spruce stands
2018
Desaine, I., Skogssallskapet, SIA, Riga (Latvia) | Baders, E., Latvian State Forest Research Inst. Silava, Salaspils (Latvia) | Katrevics, J., Latvian State Forest Research Inst. Silava, Salaspils (Latvia) | Smilga, J., Latvian State Forest Research Inst. Silava, Salaspils (Latvia) | Jansons, J., Latvian State Forest Research Inst. Silava, Salaspils (Latvia)
Browsing damages are becoming more common due to almost doubling of population densities of cervids in Latvia during last 20 years; however, the figures are still lower than those observed in western and northern European countries. Consequently, the frequency of damages in young stands is increasing, too. Protection against browsing becomes more difficult, as the trees grow older; also the bark-stripping may result in a long-term deterioration of stem quality. Therefore, the aim of the study was to assess the factors affecting bark striping damages in pole-stage Norway spruce stands. Data were collected in 4 sample plots in damaged Norway spruce stands in western Latvia, measuring the tree parameters: height, diameter, branch characteristics and damage parameters: size, proportion from the stem circumference. Results of the modelling reveal that both damage parameters were significantly influenced by the branch length and thickness in the whorl closest to the breast height and the size of damages – also by breast height diameter of the tree. It suggests that increasing productivity of trees would not reduce the browsing problem. Since the silvicultural goal is the reduction of the size of branches, especially in bottom-log of the stem, protection against bark-stripping needs to be developed and cervid population densities controlled to reduce the problem.
Показать больше [+] Меньше [-]Sanitary state of naturally and artificially regenerated Picea abies (L.) H.Karst young stands in Oxalidosa
2018
Miezite, O., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia) | Ruba, J., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia)
In Latvia, P.abies (L.) H. Karst stands occupy about 18% of the total forest area (3.01 million) forming pure and mixed stands. Regardless of the main goals, productivity of the future forest stands must be preserved; therefore, it is very important for forest management to identify risk factors. P.abies often suffers from various risk factors. The aim of the research was – to assess the sanitary state of Picea abies (L.) H. Karst in Oxalidosa, where the area of forest stands has been restored both anthropogenically and naturally. Selected young stands are located in Limbazi district of Latvia. Empirical data was collected in 5 spruce stands with the total area of 9.2 ha in Oxalidosa. In total, 67 sample plots were installed with radius of 3.99 m, measuring 799 trees. Diameter was measured for all trees in the sample plot. For sanitary state of P.abies young stands characterization damage caused by biotic factors was assessed visually after four-point scale: health tree (0), minor damage to 25% (1), moderately damaged 26 – 50% (2), severely damaged or dried – from 51% (3). Damage caused by P.abietina and browsing was found in several stands, while damage produced by P.abietina larvae was detected only in one pure stand. Occurrence of browsing damage is 10 – 28%, while damage intensity – 7.7 – 21.8%. There are significant differences between occurrence of browsing damage (p=0.001) and also between damaged tree damage intensity (p=0.003). Nature of browsing damage depends on the size of pure and mixed stand area, the location in forest massif and adjoining territory.
Показать больше [+] Меньше [-]The relation of green infrastructure and tourism in urban ecosystem
2018
Straupe, I., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia) | Liepa, L., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia)
Green infrastructure (GI) is a strategically planned network of high quality natural and semi-natural areas and provides a range of ecosystem services and protects biodiversity in urban settings. It is very important to increase understanding of the role of GI from a scientific and a socio-economic perspective. The main goal was to understand and assess the ways that tourists use from experiencing urban green infrastructure in the cities they visit. An interview questionnaire survey took place among tourists of the following countries and cities: Latvia (Riga and Jelgava) and Portugal (Lisbon and Faro). The questionnaire includes perception, psychological aspects and preferences, behaviour and activities and general questions as well as biographical information about tourists. The study represents that no significant differences have been found between respondent groups in Latvia and Portugal. The results of the survey show that in future there is a need to improve the linkage between GI and social-cultural activities in cities. Therefore, studies for tourists’ perceptions, preferences and uses of GI will provide the alternative management approaches for urban planning and tourism development in future.
Показать больше [+] Меньше [-]Density of wood of pine-tree and spruce in the mixed mature forests of the north-west Russia boreal zone
2018
Danilov, D., Leningrad Scientific Research Inst. of Agriculture ''Belogorka'', Belogorka village, Gatchina district, Leningrad region (Russian Federation) | Belyaeva, N., Saint-Petersburg State Forest Technical Univ. named after S.M. Kirov (Russian Federation);Leningrad Scientific Research Inst. of Agriculture ''Belogorka'', Belogorka village, Gatchina district, Leningrad region (Russian Federation) | Zaytcev, D., Saint-Petersburg State Forest Technical Univ. named after S.M. Kirov (Russian Federation);Leningrad Scientific Research Inst. of Agriculture ''Belogorka'', Belogorka village, Gatchina district, Leningrad region (Russian Federation)
The influence of coniferous stand composition on the density of pine (Pinus sylvestris) and spruce (Picea abies) wood is considered in this work. Processing of a large quantitative material of wood cores with the use of the ANOVA and rank analysis made it possible to reveal the influence on the macrostructure of wood of the quantitative representation of pine and spruce in the stand. In the pine part of the stand, the correlation of the wood density with the zones of early and late xylem is weak or medium. There is no wood density correlation with the width of the annual ring for stands with different shares of pine. In pine-prevailing stands with a share of pine 80% – 100%, there is a weak but reliably straight relationship between wood density and the size of late wood zone and an inverse relationship with early zone of xylem. For forest stands with a smaller part of pine participation, the relationship between these indicators is medium and reliable. For spruce, we observe a close relationship between the density of xylem and the parameters of its macrostructure in all its variants of participation in mixed coniferous plantations. In most of the studied mixed stands, the density of wood in spruce is not significantly differentiated and more homogeneous.
Показать больше [+] Меньше [-]Variation of organic matter concentrations in stream water in manure fertilized fields
2018
Miseviciene, S., Aleksandras Stulginskis Univ., Akademija, Kauno reg. (Lithuania)
The article provides the research data on the variation of organic matter in the Jaugila Stream, which flows through drained fields fertilized with organic fertilizers. The aim of the research was to determine the effect of manure application in drainage basin to the changes of organic matter concentration in the Jaugila Stream. Water samples for chemical analysis were taken once a month from the drainage water and the river. The samples from the river were taken upstream and downstream manure fertilized fields and the drainage water – from the outlets of the drainage system, which drains the fertilized area. Water analysis was performed by the Analytical Laboratory of Chemical Analysis of the ASU Water Research Institute. BOD7 was determined by titrimetric method. The research has shown that a greater impact on the increase of BOD7 concentrations in the Jaugila Stream was due to the stream water, saturated with the organic matter, flowing from the upstream areas, rather than the drainage water flowing into this stream from manure fertilized area. The assessment of BOD7 concentrations according to the water quality requirements for surface waters determined that in most cases the water of the Jaugila Stream, both in above and below fertilized areas, was in a very good or good ecological status. The impact of manure fertilized areas on the organic matter concentration in the stream was determined to be minimal, as the statistical analysis of the data has shown that the difference between BOD7 concentrations above and below fertilized areas is negligible.
Показать больше [+] Меньше [-]Food research opportunities and challenges: methods in food safety and functional food development: a review
2018
Karus, A., Estonian Univ. of Life Sciences, Tartu (Estonia) | Karus, V., Estonian Univ. of Life Sciences, Tartu (Estonia)
Large amounts of waste and by-products which are suitable for further use are generated in the food production chain. Globally, one-third of the food produced virtually becomes waste, in total 1.3 billion tonnes per year. The livestock sector is experiencing new challenges in the food and feed supply chain and waste valorization and there is a considerable diversity in animal origin food processing systems and broad knowledge base of expertise across Europe. However, due to local food production peculiarities, there is a considerable discrepancy in the waste management and processing methodology. An increasing amount of different novel feed and new functional food is available. These new products require a proper authentication and health and safety verification. Available know-how is increasing exponentially and therefore the potential for new and old bioactive component production from various currently poorly used materials is huge. Similarly, our knowledge about threats and food/feed safety is increasing. It is crucial to keep the balance between these processes. There are also several obstacles in data harmonization (data collection, used methodologies and reliability) and in data quality (lack of the comparability and completeness). The aim of the paper is to summarize the challenges in food research related to latest developments in methods.
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