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The change of natural landscape in Lithuania 全文
2020
Ivaviciute, G., Vytautas Magnus Univ., Kaunas (Lithuania);Kaunas Forestry and Environmental Engineering Univ. of Applied Sciences (Lithuania);Klaipeda State Univ. of Applied Sciences (Lithuania)
The purpose of this article is to carry out an analysis of the natural landscape of the Republic of Lithuania in 2004–2019. During the preparation of the article, the following scientific methods were used: literature analysis, determination and evaluation of the current situation, grouping method, comparison method, graphical method, analytical and statistical analysis methods, logical analysis. The article analyses the change of the area of natural (natural, subnatural) landscape components (natural forests, wetlands, water bodies) during the period between the years 2004 and 2019. The analysis showed that the two components of the natural landscape of the Republic of Lithuania during 2004–2019 increased: the forest area (132,849.03 ha or 6.15%) and water bodies (3,668.49 ha or 1.38%). Unfortunately, the area of wetlands has decreased by 50,990.20 ha (35.05%). During the analysed period, the natural landscape of Lithuania increased by 85527.97 ha or 3.39%. At present, it is particularly important to care for and restore valuable landscape complexes to fulfil their ecosystem functions. One of the most important challenges is to reconcile urbanization and nature conservation so as not to reduce significant areas of the country’s natural landscape.
显示更多 [+] 显示较少 [-]Impact of the use of existing ditch vector data on soil moisture predictions 全文
2020
Ivanovs, J., Latvian State Forest Research Inst. Silava, Salaspils (Latvia) | Stals, T., Latvian State Forest Research Inst. Silava, Salaspils (Latvia) | Kaleja, S., Latvian State Forest Research Inst. Silava, Salaspils (Latvia)
Wet soils play an important role in hydrological, biological and chemical processes, and knowledge on their spatial distribution is essential in forestry, agriculture and similar fields. Digital elevation models (DEM) and various hydrological indexes are used to perform water runoff and accumulation processes. The prerequisite for the calculation of the hydrological indexes is the most accurate representation of the Earth’s surface in the DEM, which must be corrected as necessary to remove surface artefacts that create a dam effect. In addition, different resolutions for DEM give different results, so it is necessary to evaluate what resolution data is needed for a particular study. The aim of this study is to evaluate the feasibility of using existing ditch vector data for DEM correction and the resulting implications for soil moisture prediction. Applied methodology uses a network of available ditch vectors and creates gaps in the overlapping parts of the DEM. The data were processed using open source GIS software QGIS, GRASS GIS and Whitebox GAT. Ditch vector data were obtained from JSC Latvian State Forests and the Latvian Geospatial Information Agency. The results show that by applying the bottomless ditch approach in forest lands on moraine deposits, depending on the accuracy of the ditch vector data, the values of the prediction of the soil wetness both increase and decrease. On the other hand, in forest lands on graciolimnic sediments it is visible that predicted soil wetness values increase in the close proximity of ditches. For forest lands on glaciofluvial and eolitic sediments there were no visible changes because of lack of ditches.
显示更多 [+] 显示较少 [-]Financial sector evolution and competencies development in the context of information and communication technologies 全文
2020
Arefjevs, I., BA School of Business and Finance, Riga (Latvia) | Spilbergs, A., BA School of Business and Finance, Riga (Latvia | Natrins, A., BA School of Business and Finance, Riga (Latvia | Verdenhofs, A., Riga Technical Univ. (Latvia) | Mavlutova, I., BA School of Business and Finance, Riga (Latvia | Volkova, T., BA School of Business and Finance, Riga (Latvia
The development of information and communication technologies (ICT) has a significant impact on the business model of companies operating in the financial sector. Digital transformation leads to changing existing business model rapidly, as well as necessity of developing new processes specifically related to the use of ICT in business processes, development of new products and updating existing ones. At present, changes in the demand for ICT related processes in financial sector are observed both through the development of different technologies and their applications core or ancillary processes (e.g. innovations in payment systems including crypto currencies, blockchain-assisted smart contract, credit markets and insurance including peer-to-peer lending). Based on the opportunities offered by ICT, new business models need to be developed in the financial sector to transform these capabilities into new products and services that respond to changing customer demand. The aim of research to investigate the changes taking place in financial sector in the light of developments in ICT for acquisition of necessary competencies. Research methodology includes systematic review of scientific literature, analysis of selected financial sector statistics, semi-structured industry expert interviews and statistics analysis. The empirical study is limited to the financial sector of Latvia. Although due to the global nature of the financial sector the research findings could be applied internationally.
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2020
Bumanis, N., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia) | Vitols, G., WeAreDots Ltd., Riga (Latvia) | Arhipova, I., WeAreDots Ltd., Riga (Latvia) | Meirane, I., WeAreDots Ltd., Riga (Latvia)
Deep learning algorithms are becoming default solution for application in business processes where recognition, identification and automated learning are involved. For human identification, analysis of various features can be applied. Face feature analysis is most popular method for identification of person in various stages of life, including children and infants. The aim of this research was to propose deep learning solution for long-term identification of children in educational institutions. Previously proposed conceptual model for long-term re-identification was enhanced. The enhancements include processing of unexpected persons’ scenarios, knowledge base improvements based on results of supervised and unsupervised learning, implementation of video surveillance zones within educational institutions and object tracking results’ data chaining between multiple logical processes. Object tracking results are the solution we found for long-term identification realization.
显示更多 [+] 显示较少 [-]Changes in the engineering students’ procrastination self-evaluation within the experimental approbation of career education program 全文
2020
Jerkunkova, A., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia) | Katane, I., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia) | Baltusite, R., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia)
One of the modern education problems being investigated is a phenomenon of student procrastination and minimisation of its influence on achievement of career goals. A transformative pedagogical experiment was carried out involving 1st year engineering students of Latvia University of Life Sciences and Technologies during the 2018/2019 academic year. The aim of the transformative pedagogical experiment was to promote the reduction of student procrastination levels and achievement of their goals by practical experimental approbation of a career education program. During the experiment, self-evaluation of student procrastination was performed before and after the implementation of the career education program. The methodology included 20 indicators of procrastination self-evaluation. The program included three topic-based parts: 1) understanding and setting student career goals; 2) defining procrastination levels and factors; 3) the influence of procrastination minimisation on career goals’ achievement. The study results allowed to conclude that due to the career education program elaborated and implemented in practice, substantial changes in student procrastination self-evaluation took place during the transformative pedagogical experiment. There was a significant difference in student procrastination levels before and after the transformative pedagogical experiment. The study results demonstrated that the elaborated and experimentally implemented career education program is valid and can be further used for minimisation of student procrastination, it can contribute to career goals’ achievement and for the reduction of early discontinuation of studies and dropping out of university as there is a correlation between procrastination and dropout phenomena.
显示更多 [+] 显示较少 [-]Structural diversity of dead wood in small-scaled protected forest parcels in Latvia 全文
2019
Liepa, L., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia) | Straupe, I., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia) | Miezite, O., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia) | Jansons, A., Latvian State Forest Research Inst. Silava, Salaspils (Latvia)
Dead wood is a significant component in forested ecosystems. In Fennoscandia and Baltic countries, set-aside forest areas, also called woodland key habitats (WKHs), have been created for nature conservation purposes in the production forest landscape. We performed a comparative study on dead wood substrate availability in different WKH types in Latvia. We measured standing trunks and downed logs to estimate biological quantities and qualities for coarse woody debris substrate. In this study, we found out that dead wood availability ranges, on average, from 38.2 to 149.5 m**3 haE−1. This study showed that moderate quantity and quality of dead wood has been found in different types, but the fine quality coarse woody debris was scarcely presented. In general, WKHs provide moderate and high level of qualities and quantities of structural features in the production forest landscape.
显示更多 [+] 显示较少 [-]Restoration of spruce and pine in North-West Russia 全文
2019
Belyaeva, N., Saint-Petersburg State Forest Technical Univ. named after S.M. Kirov (Russian Federation) | Danilov, D., Leningrad Scientific Research Inst. of Agriculture ''Belogorka'', Belogorka village, Gatchina district, Leningrad region (Russian Federation);Saint-Petersburg State Forest Technical Univ. named after S.M. Kirov (Russian Federation) | Mandrykin, S., Saint-Petersburg State Forest Technical Univ. named after S.M. Kirov (Russian Federation)
The analysis of regeneration processes on post-agrogenic lands allows establishing patterns and features of succession processes in phytocenosis, to identify the most appropriate measures to promote natural regeneration and to establish the possibility and feasibility of the production of forestry crops on lands left out of agricultural use. A study of forest regeneration processes in areas of fallow land for agricultural purposes adjacent to the floodplain of the Oredezh River in Gatchina district of Leningrad region. On the prepared study plots (0.25 ha) in different elements of the slope relief, the natural regeneration of pine and spruce and living ground cover was also taken into account. The soils on the objects of the study are agricultural soils of different thickness, from 30 to 45 cm. In two areas the soil is turfy, well-cultivated, concealed podzolic, ferrous illuvial soil on sands. On plots No. 3–5, the soil is turfy, well-cultivated, concealed podzolic, ferrous illuvial, clayey, on a red loam. The purpose of the study was to identify the nature of forest regeneration processes in areas of fallow land for agricultural purposes. It has been established that the composition of the emerging undergrowth depends on a number of factors: the type of soil, the taxation characteristics of the adjacent forest, the forest vegetation subzone, and the living ground cover. In these soil conditions on the deposits, young mixed undergrowth with a predominance of spruce and pine after a meadow stage of ruderal vegetation is formed.
显示更多 [+] 显示较少 [-]Macrostructure and density of pine and spruce wood on fallow lands on North-West of Russia 全文
2019
Danilov, D., Leningrad Scientific Research Inst. of Agriculture ''Belogorka'', Belogorka village, Gatchina district, Leningrad region (Russian Federation);Saint-Petersburg State Forest Technical Univ. named after S.M. Kirov (Russian Federation) | Janusz, S., Saint-Petersburg State Forest Technical Univ. named after S.M. Kirov (Russian Federation)
Growing spruce and pine wood on land being out of active agricultural use is important for many European regions. The study of the qualitative characteristics of coniferous wood makes it possible to predict target indicators of the obtained raw materials. The influence of xylem structural elements on the density of spruce pine wood on the postagrogenic lands of the boreal zone of Russia was studied. The objects of the research were spruce-pine stands growing on old arable land in the Gatchina district of the Leningrad region. Depending on the share of the species, various anatomical indicators of the macro-structure of wood influence the formation of the spruce and pine wood density. For the spruce part of the forest stand, the width of the annual increase makes a greater contribution to the formation of indicators of wood density. For the pine part of the forest stand the density of the wood correlates with the proportion of late xylem. With a different proportion of the species, the influence of macro-structural elements on the density of wood changes. Conducted analysis of variance showed a significant effect of the forest stand composition on the anatomical macro-structure of spruce and pinewood.
显示更多 [+] 显示较少 [-]Evaluation of potential impact of soil scarification pattern on trees’ damages in future commercial thinning 全文
2019
Kaleja, S., Latvian State Forest Research Inst. Silava, Salaspils (Latvia) | Spalva, G., Latvian State Forest Research Inst. Silava, Salaspils (Latvia) | Lazdins, A., Latvian State Forest Research Inst. Silava, Salaspils (Latvia)
The aim of the study is to analyse the empirical data collected in 2017, explaining the distribution of mechanically damaged trees left after the commercial thinning, in order to characterize the potential impact of the change of soil scarification working direction on the intensity of damage to the trees left in the felling during the following pre-commercial thinning. The study found that extraction or leaving logging residues in the felling area did not significantly affect the productivity of the soil scarification, but in areas where logging residues were extracted, the depth of the furrows increased significantly, implying a better quality of soil preparation in these areas. The study did not identify the correlation between strip-road patterns (combined or uncoupled ends) with damage intensity, but the research hypothesis was confirmed that the number and proportion of damaged trees is significantly increasing at the ends of the technological corridors. A bigger increase of proportion of damaged trees at the end of strip-roads was found in pine stands. When modelling the effect of soil preparation and logging design on the proportion of damaged trees, species specific parameters should be used – the proportion of damaged trees at the corridor ends in pine stands is 68%, in spruce stands – 45% compared to the rest of the stand. The rest of the stand can be characterized by production statistics or by the results of the study – the average proportion of damaged trees in spruce stands is 4.9% and in pine stands – 0.8% of the remaining trees.
显示更多 [+] 显示较少 [-]Forest management challenges and opportunities of two-layered birch and spruce stands in Latvia 全文
2019
Vuguls, J., Latvian State Forest Research Inst. Silava, Salaspils (Latvia) | Snepsts, G., Latvian State Forest Research Inst. Silava, Salaspils (Latvia) | Libiete, Z., Latvian State Forest Research Inst. Silava, Salaspils (Latvia) | Zalitis, P., Latvian State Forest Research Inst. Silava, Salaspils (Latvia)
Forestry in Latvia in the 20th century was strongly focused on the establishment and management of pure Scots pine and Norway spruce stands trying to avoid any admixture of other tree species. Knowledge on the economic feasibility of the mixed stands’ management is still rather poor in Latvia, while at the same time the establishment of mixed stands of Norway spruce and birch species has become an attractive management objective in Finland and Sweden. This paper used the data from the Latvian National Forest inventory to quantify the amount of birch stands with the second layer of spruce, as the first step to justify the development of recommendations for alternative management options in this type of stands. According to the results, there are 121 752 ha of birch stands with the second layer of Norway spruce, and most of those are located in Hylocomiosa, Oxalidosa, Myrtillosa mel. and Myrtillosa turf.mel. site types. The mean standing volume of birch stands with Norway spruce understorey was higher than in birch stands with no spruce understorey, and Hylocomiosa, Oxalidosa, Myrtillosa mel. were the most productive site types both in terms of total standing volume and that of the Norway spruce growing in the second layer. Analysed data also revealed that the management of birch stands already now differs strongly in state and private forests, in the latter being more focused on selective fellings. It is possible to develop and test alternative management methods of birch stands with the second layer of Norway spruce to maximise yield and reduce expenses of forest regeneration.
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