Nowadays, the use of Unmanned Aerial Vehicle flying at a low altitude in conjunction with photogrammetric and LiDAR technologies allows to collect images of very high-resolution to generate dense points cloud and to simulate geospatial data of territories. The technology used in experimental research contains reconstruction of topography of surface with historical structure, observing the recreational infrastructure, obtaining geographic information for users who are involved in preservation and inspection of such unique cultural/ heritage object as are mounds in Lithuania. In order to get reliable aerial mapping products of preserved unique heritage object, such photogrammetric/ GIS procedures were performed: UAV flight for taking images with the camera; scanning surface by LiDAR simultaneously; processing of image data, 3D modelling and generation of orthophoto. Evaluation of images processing results shows that the accuracy of surface modelling by the use of UAV photogrammetry method satisfied requirements – mean RMSE equal to 0.031 m. The scanning surface by LiDAR from low altitude is advisable, relief representation of experimental area was obtained with mean accuracy up to 0.050 m. Aerial mapping by the use of UAV requires to specify appropriate ground sample distance (GSD) that is important for reducing number of images and time duration for modelling of area. Experiment shows that specified GSD of 1.7 cm is not reasonable; GSD size increased by 1.5 times would be applicable. The use of different software in addition for DSM visualization and analysis is redundant action.

Experience saved in the construction industry shows that the timber portal frames with semi-rigid connections at knee joint exhibit permanently increase displacements at the knee and apex point. Normally, timber portal frame with semi-rigid knee joint connection is made with mechanical fasteners located in double circles and cannot be designed without relevant rotation at connection during structures’ exploitation time. The only way to increase connection rigidity is to rise distance from fasteners location at connection, but at the same time, the tension and shear stress become significant at the external section of members. The previous experience is obtained by a model testing showing that deformations at semi-rigid connections are non-linear. These were tests under short-term load and did not disclose creep effects, which can be significant. This study is aimed at the examination of increasing deformations with time under constant static load (creep effects) in semi-rigid dowelled connection. Experimental test models were made and set under long-term load in controlled environmental conditions (heated laboratory room). Results show a significant creep influence to decrease connection stiffness. Corresponding numerical test of orthotropic 3d model by Dlubal RFEM software tools was performed analysing the value of expected deformations. Results of the numerical test showed that friction between timber elements and extra nuts on bolts can increase connection stiffness. Research results in this stage show that the creep can affect connection stiffness more than expected. Also, experimental test results showed lower deformation values comparing with the ones obtained by the numerical test.

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.

Research in many countries across the world, including Latvia, shows that youth participation in national defence is a topical issue. So far, scholarly research focusing on the promotion of youth participation in national defence and the provision of career support at school age and after finishing school is scarce. Therefore, the aim of the research was to establish the basis for young people’s military career in national defence. Research results show that there is both theoretical and legal basis for young people to start a military career, already during school years. Based on the broad meaning of the concepts career and career development, young people’s self-development, self-management and self-actualisation in various fields of human activity over one’s lifetime emerge as topical issues. Such activities of various kinds may follow one another in succession or take place simultaneously, in parallel, in accordance with dual career theories. The beginning and development of young people’s military career in Latvia can occur in the context of various activities already present and available in the near future: 1) participation in the Latvian Youth Guard as a type of non-formal education, 2) acquisition of National defence training at school in the context of formal education, 3) upon reaching legal age, voluntarily joining the Latvian National Guard, which is a component of the National Armed Forces of the Republic of Latvia.

Dialogue (discourse) is the main indication leading us to the conclusion that mediation is constructive. Discourse, the main form of dialogue, allows to achieve a positive result of mediation – an agreement between the participants of the conflict, as well as to learn dialogue communication skills. The aim of this study is to determine the types of dialogue used in mediation, the usage of recognized dialogue, and to find methods for assessing the dialogue (discourse) skills that need to be taught to the participants of the conflict, as well as future mediators and to evaluate the effectiveness of mediation. The research was conducted based on the theoretical methods of analysis of modern concept of dialogue and empirical testing methods (using questionnaires) of the participants of the conflicts and future mediators. Methods of mathematical statistics were used, when processing and analysing the results of the questionnaires. As a result of this work, the types of dialogue used in mediation are identified; recommendations on the choice of components and barriers of dialogue to be considered by the mediator when training participants in the conflict and future mediators are made, as well as recommendations on assessment the effectiveness of mediation are offered.

The capercaillie Tetrao urogallus L. is a typical bird species inhabiting structurally diverse coniferous forests. To increase the habitat quality of capercaillie leks, experimentally the habitat restoration in degraded ecosystems has been practiced. The main habitat restoration events are related to the reversion of hydrological regime and understorey layer management. The aim of this study was to find out how the management of lek sites – mowing of Ledum palustre L. and ground vegetation – promotes the regeneration of the vegetation typical of the capercaillie leks. Three sample plot blocks of 10x30 m have been established, which have been divided into 3 variants of 10x10 m. The first is a control plot, in the second plot an entire ground vegetation mowing was performed, while in the third plot – the ground vegetation mowing in a 3 m wide strip was carried out. The vegetation was determined using the BraunBlanquet recording form before the management – in August 2015, and after the management – in August 2017. The condition of the habitat of capercaillie is inadequate before management, since Ledum palustre prevails in the ground vegetation. Both types of ground vegetation management have had a significant impact on the projective cover of Ledum palustre. After mowing the entire area, it has decreased by half, but after mowing in a strip, it has decreased by 30%. The ground vegetation mowing in a strip enhances positively the regeneration of dwarf shrubs and herbaceous vegetation.

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.

A demand for wood resources is increasing. In addition to drainage and appropriate regeneration and thinning, the forest soil fertilization may increase the future harvest rates. Therefore, the improved growth of forest stands raises in priority among the research topics related to forestry. The objective of the study is to evaluate the impact of nitrogen fertilizer on soil water and throughfall water chemical composition to elaborate recommendations for the forest fertilization. The trials were conducted in a birch stand and in three coniferous stands. Nitrogen containing mineral fertilizer (ammonium nitrate) was distributed in the study sites, while the control plots were left without any treatment. The water samples were collected a season before and a season after the soil treatment. The pH level, total nitrogen, potassium and phosphate were determined in throughfall and soil water samples. The chemical properties of throughfall water differed depending on the forest stand type. The concentration of nitrogen was higher in throughfall water samples collected from the birch stand. The mean concentration of total nitrogen was 1.6 ± 0.3 mg LE−1 in the throughfall water samples from the birch stand compared to 1.03 ± 0.11 mg LE−1 in the throughfall water samples from the coniferous stands. Although the forest soil was enriched with the nitrogen fertilizer, there was a significant increase in concentrations of potassium and phosphate in soil water samples from certain stands. It can be explained with changes in pH level that occurred after the forest soil treatment with ammonium nitrate. There was also a significant increase in total nitrogen concentrations in soil water samples at the depth of 30 cm from the treated plots of the coniferous stands – 15 ± 6 mg LE−1, compared to 1.5 ± 0.03 mg LE−1 in the samples from the control plots. However, the concentrations decreased within two months and remained at a steady rate – slightly above the control level.

Forests offer a wide variety of ecosystem services, including cultural or recreational services. In that sense, state-owned forest lands hold the biggest responsibility to acknowledge and provide these services, where it is economically and ecologically viable. Suitability analysis has been extensively used to provide information on species conservation measures, and it is possible to apply similar techniques for potential supply of recreational services. A simple weighted overlay analysis was conducted to locate forest land areas most suitable for potential recreational activities. Several criteria were selected for the analysis, including forest stand parameters such as forest stand age, forest stand type and species, topographical diversity and remoteness. Basis for the weighting of the selected criteria were obtained from the social surveys, previous research work done in Latvia and the Baltics, and European scale scientific data on recreation preferences. The analysis showed that 20% of the total model area analysed provide substantially high recreation potential. Furthermore, these preliminary data can be used for surveying and facilitating community involvement processes. Local tourism and nature leisure activities can be promoted by exploring possibilities of alternative forestry planning options, utilizing such multifunctional assessments of recreational supply.

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.