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Theoretical substantiation of the competitiveness of academic staff from the perspective of educational sciences 全文
2020
Troskova, M., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia) | Katane, I., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia)
The socio-economic changes brought about by globalisation, the internationalisation and digitalisation of higher education, as well as the current demographic situation in Europe and Latvia, raise the issue of the competitiveness of academic staff in the context of multicultural higher education. The aim of the study is to provide a theoretical basis for the competitiveness of academic staff in the view of educational sciences, respecting the different trends and based on the conceptual approaches in personal/specialist competitiveness research. The following research methods were used: study, analysis and evaluation of scientific literature (theoretical research method); reflection of personal experience (empirical research method). As a result of the theoretical research, two trends for the substantiation of the concept of competitiveness in the educational sciences were identified. The first trend: the competitiveness of a person is substantiated through transfers from economic and management science, with a particular emphasis on specialist marketability and employability as a significant manifestation of competitiveness. The second trend: according to the new paradigm of competitiveness in educational sciences, the competitiveness of a human as a person and as a specialist is based on the perspective of pedagogy and psychology. The research results led to the conclusion that there are three conceptual approaches in the methodology of competitiveness research: 1) qualitative approach: identifies and lists competitive personality traits and qualities; 2) functional approach: describes the competitive behaviour of a person or specialist; 3) structural approach: competitiveness is substantiated as a complex combination of personal/ specialist qualities, identifying several structural components. All of these approaches are also characteristic to the research of competitiveness of academic staff. The following taxonomy should be respected in the substantiation of academic staff competitiveness: 1) substantiation of personal competitiveness; 2) substantiation of specialist competitiveness in the context of different industries; 3) the substantiation of the competitiveness of specifically academic staff in the context of the specifics of higher education.
显示更多 [+] 显示较少 [-]Development of young stands after different intensity regeneration fellings 全文
2019
Klavins, I., Latvian State Forest Research Inst. Silava, Salaspils (Latvia) | Kalvite, Z., Latvian State Forest Research Inst. Silava, Salaspils (Latvia) | Libiete, Z., Latvian State Forest Research Inst. Silava, Salaspils (Latvia)
The share of the renewable resources used continues to grow due to environmental, economic and political reasons. Consequently, intensification of forest management is on-going and expected to continue in the future. Logging residues, such as treetops, branches and stumps, are a significant renewable energy source. Since the logging residues are noticeably richer in nutrients than conventionally harvested stems, there is a concern related to the negative impact of intensified harvesting on the ecosystems, productivity of the sites and sustainability of forestry in general. To evaluate the impact, this study has compared different intensity harvesting effect on the next rotation young stand productivity in eight sites in Latvia. In a nutrient-rich site, the productivity of Norway spruce was higher in the whole-tree harvest (WTH) subplot comparing to stem-only harvesting (SOH) subplot three years after the planting. Productivity of Scots pine in oligotrophic conditions was observed to be higher in SOH subplot comparing to WTH subplot two and three years after planting. Furthermore, in a site on a mineral soil relatively richer in nutrients no significant differences were observed. Comparing WTH to whole tree harvest + stump biomass (SB) extraction subplots, the productivity of Norway spruce was higher in WTH four to five years after the planting; in a mixed stand of Norway spruce and black alder no productivity differences of spruce were detected, but productivity of black alder was higher in WTH+SB subplot five years after the planting; in black alder stands a significantly higher productivity was observed in WTH subplot four and five years after the planting.
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 [-]Transformation of the organic matter of forest and postagrogenic soils of the boreal zone of Russia 全文
2019
Vaiman, A., 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) | 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) | Zhigunov, A., 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)
The purpose of the study was to compare forest and postagrogenic soils by parameters such as carbon content in organic matter and total nitrogen to predict the fertility state of lands that are at the stage of restoration of woody vegetation. Areas with similar soil formation conditions were selected on the postagrogenic and forested lands having mature forest stands related with such types of forest: Myrtillosum forest, Oxalidosum and Herbosa-Composita forest, and also areas under the soil complexes of postagrogenic fallow lands. A number of physico-chemical indicators for the soil were assessed according to the methods generally accepted in soil science: the particle size distribution, the bulk density and the thickness of the pedogenic horizons were determined. An analysis of the carbon stocks in organic matter (Corg) and nitrogen (Ntotal) in the genetic horizons of the soils of myrtillosum, Oxalidosum and Herbosa-Composita forest types shows an increase in the content of organic matter and total nitrogen from Myrtillosum to Herbosa-Composita forest type. A comparative analysis of the physical and agrochemical state of postagrogenic and forest soils showed that, despite the previous anthropogenic impact, the agroland horizon retains a high content of organic matter and total nitrogen. The properties of postagrogenic soils in the studied areas are not deteriorated, and the transformation towards the natural forest soils of the region is not observed, despite the long period of fallowing.
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.
显示更多 [+] 显示较少 [-]Post-storm regeneration of Norway spruce 全文
2019
Snepsts, G., Latvian State Forest Research Inst. Silava, Salaspils (Latvia); Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia) | Donis, J., Latvian State Forest Research Inst. Silava, Salaspils (Latvia) | Strelnieks, K., MVR LUX, SIA, Riga (Latvia) | Krisans, O., Latvian State Forest Research Inst. Silava, Salaspils (Latvia) | Desaine, I., Skogssallskapet, SIA, Riga (Latvia) | Adamovics, A., Latvian State Forest Research Inst. Silava, Salaspils (Latvia)
Impact of abiotic (wind, summer drought) and secondary (bark beetle (Scolytinae)) or primary (cervids (Cervidae)) biotic factors affect the survival of Norway spruce (Picea abies (L.) Karst.) that is an economically important tree species. Norway spruce is mostly regenerated via planting – thus with significant investment. Therefore it is important to improve the resistance of Norway spruce stands as much as possible. Aim of the study was to characterize damages in Norway spruce stands by cyclonic wind storm and the regeneration of the stands, destroyed by the storm. Data from 4491 Norway spruce dominated stand, destroyed by the storm of 2005, from State Forest service database were obtained. Areas of post-storm sanitary clearcuts ranged from 0.1 to 7.6, mean 0.9 ± 0.02 ha. Most of the clearcuts were larger than 0.5 ha, demonstrating a relatively large size of gaps created by this natural disturbance. Changes of dominant trees species after the storm were statistically significantly affected by the forest type and type of regeneration. Overall, it happened in 55% of the former Norway spruce areas and was predominantly in cases, where natural regeneration was practiced. No indications of measures to increase stability of future stands against wind damages were found.
显示更多 [+] 显示较少 [-]Analysis of landscape paintings to highlight the importance of forest ecosystem services in Latvia 全文
2019
Paulina, I., Latvian State Forest Research Inst. Silava, Salaspils (Latvia) | Libiete, Z., Latvian State Forest Research Inst. Silava, Salaspils (Latvia)
Forests and woodlands provide a wide variety of ecosystem services that are usually classified within three categories: provisioning services, regulating (supporting) services and cultural services. While provisioning and regulating services are widely analysed, there is a lack of information about the cultural ecosystem services, particularly some sub-categories of these. In this study, we have focused on inspiration for creativity as a sub-category of cultural ecosystem services provided by forests and analysed the depiction of forest ecosystems in landscape paintings of Latvian artists. It may be concluded that forest ecosystems serve as an important source of inspiration for creativity and art, as may be seen in the landscape paintings of Latvian artists of the 20th century. Characteristic landscape features of birth and living places of the artists are reflected in their works. The performed analysis is the first of its kind in Latvia, and it may be further expanded, either by incorporating other aspects of creativity or adding economic dimension, for example, by surveying the art market.
显示更多 [+] 显示较少 [-]The efficiency of forest drainage system sedimentation ponds in the context of water quality 全文
2019
Kalvite, Z., Latvian State Forest Research Inst. Silava, Salaspils (Latvia) | Libiete, Z., Latvian State Forest Research Inst. Silava, Salaspils (Latvia) | Klavins, I., Latvian State Forest Research Inst. Silava, Salaspils (Latvia)
The establishment, maintenance and renovation of forest drainage systems are carried out to ensure the development of high quality forest stands and to secure access to forest resources, but it also poses a risk of erosion and increased discharge of suspended solids and nutrients associated with it. The aim of the study was to analyse the efficiency of standard-sized sedimentation ponds built by JSC ‘Latvia’s State Forests’ for sediment and nutrient retention during and after drainage network maintenance. To assess the efficiency of standard-sized sedimentation ponds six study sites were established and various chemical and physical parameters were measured for three years to evaluate water quality and to estimate runoff of plant nutrients and suspended solids. Sampling was carried out before and during drainage network maintenance and during two years following it. Despite the fact that some effect in reducing suspended solid export from catchments was observed, the results revealed insufficient efficiency of the sedimentation ponds in retaining plant nutrients and eroded matter during and after the drainage network maintenance. Retention of Ntot, N-NO3 sup(-) , P-PO4 sup(3-), N-NH4 sup(+) and DOC was ambiguous. It was concluded that other water protection structures should be considered or different parameters of sedimentation ponds should be used to improve the water quality exiting the drainage systems and entering waterbodies.
显示更多 [+] 显示较少 [-]Dynamics of meteorological and hydrological droughts in the agricultural catchments 全文
2019
Kubiak-Wojcicka, K., Nicolaus Copernicus Univ., Torun (Poland)
The aim of the paper is to determine the relationship between meteorological drought and hydrological drought in the agricultural basin of the River Osa (northern Poland) in the years 1966-2015. Meteorological droughts appear as a result of insufficient amount or lack of atmospheric precipitation. As a consequence of meteorological droughts occurrences, there appear hydrological droughts which are characterized by low discharges of a river. Standardized Precipitation Index (SPI) and Standardized Runoff Index (SRI) indicators were used for the identification of droughts at various accumulation periods, i.e. 1, 3, 6, 9 and 12 months. In the years 1966-2015, there were identified from 63 (SPI-1) up to 10 meteorological droughts (SPI-12), while hydrological droughts – from 22 (SPI-1) to 8 (SPI-6, 9 and 12). The strongest relationship between the two kinds of droughts occurred in the periods of accumulation from 9 to 12 months. The values of the correlation coefficient between the meteorological and hydrological droughts were above 0.5 in those cases. Those indicators can be used for a system of early drought warning, which is of particular importance for crop production in agricultural areas. Long-lasting meteorological droughts contribute to increase of water intake for irrigation purposes, thus deepening the hydrological drought. As a consequence of the prolonged and intense hydrological drought, further irrigation may be impossible due to too low river discharges.
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