Plant factories provide possibilities to get optimal yield of green leafy vegetables entire year independent from the season. The technology of light-emitting diode (LEDs) light has become one of the most powerful tools in photophysiological researches of various horticultural plants. In order to manage plant physiology and improve productivity, it is necessary to develop new LEDs technologies in horticulture. The aim of the study was to investigate different lighting intensities and elevated red light (660 nm) effect on tatsoi photosynthetic parameters. All plants were grown under the same light sources where overall photosynthetic photon flux density (PPFD) varied from 200 to 300 µmol mE-2 sE-1. Three days before harvesting red light intensity (640 and 660 nm) was increased until 132 µmol mE-2 sE-1 and 660 nm until 188 µmol mE-2 sE-1 at 16 hours photoperiod. In the last treatment merely 24 hours photoperiod was applied. The photosynthetic indices in tatsoi were determined by non-destructive methods using LI-6400XT portable photosynthesis system, OS5p fluorometer, DUALEX optical sensor and CID leaf spectrometer. Research was performed in 2017 – 2018 winter season. The obtained data revealed that the total photosynthetic photon flux density (PPFD) at level of 200 µmol mE-2 sE-1 was sufficient for optimal CO2 assimilation in tatsoi plants. The increased PPFD of LED light at pre-harvest stage resulted in reduced photosynthetic parameters of plants.

The objective of the study was to analyze measurements of the sires used in Latvian Warmblood (LWB) and Latvian Heavy Warmblood (LHWB) breeding programs in the period 2003 – 2017, two major horse populations in Latvia included in one studbook. The Latvian Warmblood has an open studbook for breeding sport horses, whereas the Latvian Heavy Warmblood is a partly closed studbook. Measuring information for all sires with at least one foal born (n=834) in the respective time period was retrieved from the Latvian horse database, with 673 stallions measured at least once. The data consisted of direct measurements – height at withers, chest circumference and cannon bone circumference – and two calculated indices – massivity index and boniness index. Average values of adult stallions were analyzed in four groups – LWB, LHWB, ‘other warmbloods’ and refining breeds, with LWB and ‘other warmbloods’ showing similar average values. Sires were divided by use in breeding into 3-year periods to observe a possible change in the breeding objective and stallion choice, however, no significant differences were found in LWB or LHWB. Average measurements of stallions used in the LWB breeding program (different breeds) were 168.6 ± 4.3 cm for height at withers, 194.4 ± 6.6 cm for chest circumference, 21.8 ± 1.0 cm for cannon bone circumference, massivity index 115.5 ± 3.1, boniness index 13.0 ± 0.5. Average measurements of stallions used in the LHWB breeding program (only LHWB stallions) were 167.6 ± 4.6 cm, 201.4 ± 7.3 cm, 23.7 ± 1.0 cm, respectively, and massivity index 120.0 ± 5.0, boniness index 14.1 ± 0.6. Significant differences between LWB and LHWB stallions were observed in all parameters, except height at withers, and between measurements at the age of 2, 3, 4 years and adult (5 and more years).

Farming outputs in agriculture depend on the nature of production, i.e. different farming systems generate different outputs. All these outputs are important for the society, and, therefore, require an integrated approach in view of the specific farming characteristics, where market and non-market outputs are taken into account. Therefore, the paper focuses on analysis of farming system outputs and methods of their evaluation. The objectives of this paper are to define the features of different farming systems and their outputs, then, to analyse the methods of evaluation of farming system outputs used in the studies. In order to achieve the research aim, analysis of economic scientific literature has been conducted; characteristics of farming systems and their outputs have been analysed; evaluation methods of the market and non-market farming system outputs, revealing their advantages and disadvantages, have been examined. Methods of systemic and logic analysis have been applied to analysis of the farming system outputs and their evaluation. The analysis has shown that intensive farming systems generate more market goods, while extensive farming systems – more public goods. Price-based methods are mostly used for the evaluation of market outputs of farming systems. Stated preferences methods are the most universal techniques used for the determination of the values from non-market farming system outputs. Hedonic pricing approaches are used for evaluation of specific agricultural public goods related to recreation or leisure and related to the particular groups of users.

Every day millions of new data records with spatial component are produced in the world, which provide valuable information to make decisions and solve business-related issues. However, a large part of this data is hardly analysed because of their different structures and schemas. The aim of the paper is to improve the integration, processing and analysis of unstructured spatial data. During the research, the author analysed geospatial data types and sources, explored NoSQL solutions for geospatial data processing and chose the open-source tools which are the most appropriate for the stated goals, as well as analysed the coverage of forest areas with protected zones using MongoDB database capabilities and visualized results in a map, using QGIS software. MongoDB is a useful tool for geospatial data analysis and has a large number of embedded topology analysis functions and has drivers for widespread programming languages like JavaScript, Python, PHP, Java, Scala, CNo., C, C + +, etc. QGIS has extensions that allow to make connections to databases, including a connection with MongoDB. Using these features, the developers can develop geographic information systems to analyse geospatial data – structured, semi-structured and unstructured. Generally MongoDB is used for real-time data analysis; however, complicated analysis of large data sets can take up to hours and even days, so it is still necessary to find the best solution to get results in an acceptable time for users. Using MongoDB together with Apache Hadoop – the framework to support big data applications – could be a possible solution for this problem.

This article presents theoretical and practical aspects of content marketing decisions for the customer value creation in social networks by using the case of the organic farm ʻIlzenberg manor’. Focus of this paper is to determine which content marketing decisions create the biggest value for the customer in social networks. The first part of the paper deals with theoretical insights into the content marketing decisions and their ability to create the customer value in social networks. Findings of theoretical analysis disclose that there are interfaces between content marketing, separate content marketing decisions and the customer value in the context of social networks. Respectively, it leads to an assumption that the usage of content marketing decisions can be valuable for the customer value creation in social networks. The second part of the paper focuses on the case analysis of the organic farm ‘Ilzenberg manor’. In order to determine which content marketing decisions create value for the customer in social networks, authors examine a correlation between separate content marketing decisions and consumer value indicators by using data from ʻIlzenberg manor’ Facebook page. The obtained results expose that not all content marketing decisions create value for the customer in social networks. Hence, it means that a selection of separate content marketing decisions in social networks can be made through the customer value perspective. The article ends with insights, conclusions, limitations and future research possibilities.

The paper covers analysis of pre-commercial thinning performed in private forests over the period of 2007–2017. Since 2007, permanent and considerable European Union subsidies for pre-commercial thinning have been available; resulting in a significant increase in area of thinned young stands in private forests. The aim of this research is ascertain pre-commercial thinning activity depending on the type of forest owner (individuals, legal persons or local municipality), forest stand type (forest stand or plantation) and origin (natural or artificial) as well as the forest owner’s intention to apply for European Union subsidies. Data analysed were obtained from Forest State Register – national data base, managed by state authority State Forest Service and continued analysis comprise two main topics – ascertain amount and type of young stands owned by different type of private forest owners and amount and type of conducted pre-commercial thinning. In comparison with other type of forest owners, legal persons have significantly higher amount (47%) of young plantation forest and forest stands from the total forest stands area. The highest intensity of thinning was conducted in plantation forests of artificial origin owned by legal and physical persons, also forest stands with artificial origin owned by physical persons. The current period for European Union Rural development programme will be over in 2020; therefore, it is important to analyse the existing approach of granting subsidies to forestry and find the improvement necessary for the planning period from the year 2021.

The objects of research are the lime-tree forests of the Leningrad region. The studies were carried out on 2 permanent plots established by the authors in May 2013 in the Lisino forest district (Leningrad region, Russia). The goal of research was to obtain a complex characteristic of stands dominated by linden (Tilia cordata). The objective of the research included a taxation and geobotanical description on permanent plots and studies of the soil cover (morphological and agrochemical characteristics of soils). The general health status of stands on the surveyed areas was determined as satisfactory – mean score 2.5 and 2.8 (relevant health status was determined with the help of the following 6-grade scale for each tree: 1 – no signs of weakening; 2 – weakened tree; 3 – very weakened tree; 4 – partial mortality of the tree; 5 – dead-standing trees of the current year; 6 – dead-standing trees of previous years). The average mortality rate varies from 3.05% year-1 on the sample plot 2 to 5.7% year-1 on the sample plot 1. Vegetation on sample plots attributes to a nemorose-herbal series of forest types, soils – to a podzolic type with a weak development of the podzol-forming process. They were well-mediated ones by humus in the upper horizon. This fact was facilitated by the lime litter: a lime has a deep root system to take up nutritional chemicals from a greater depth, where moraine loams enriched with calcium carbonate located. Old-aged forests of this type are being in the phase of gap dynamics now. This means that they can occur for a rather long time in the same place, however, the lime-tree forests of natural origin are constantly under threat of being replaced by spruce. The results of our study have shown that low levels of soil mineral nutrients supply are sufficient for the successful linden growth.

The study represents results on remote sensing methods based evaluation of land use and land use changes in former and existing peat extraction areas in Latvia. The aim of the study is to elaborate activity data set for the National GHG inventory for the wetlands remaining wetlands for peat extraction. The study results provide sufficient data for application of the default emission factors for the peat extraction sites and flooded lands. Abandoned peat extraction fields, which are not yet afforested, flooded or rewetted, should be reported as peat extraction sites following a conservative approach in application of the emission factors. The study results can be used to report land use changes since 1990; however, linearized approach in calculation of the land use change may result in overestimation or underestimation of GHG emissions in certain periods of time. According to study results, the area of peat extraction sites is considerably bigger than currently reported in the National GHG inventory, mainly due to considerable areas of abandoned peat extraction fields. Flooded lands may be a significant source of emissions and should be introduced in the National GHG inventory to secure consistency of reporting. Methodology for calculation of GHG emissions from flooded lands should be also elaborated. It is also necessary to elaborate emission factors for fertile and no fertile peat extraction sites and continue work on separation of different soils in the inventory to increase accuracy of calculations.

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.

The aim of the research is to find out changes in productivity depending on the diameter of the tree to be cut as well as the most important factor influencing the reduction of productivity using small size forest machines in thinning in Latvia. The equipment used in the study – both the harvester and the forwarder is Vimek. The results of the research confirm the appropriateness of the exact technique in thinning if diameter of the harvested trees is 3 to 30 cm. The average productivity of the harvester achieved with a harvester head Keto Forest Eco (option 2) in Norway spruce stands with 8 cm weighted average tree reached 9.59 m**3 hE-1, in deciduous tree stands with 9 cm weighted average was 10.17 m**3 hE-1, but in Scots pine stands with 12 cm average weighted tree diameter reached 10.19 m**3 hE-1. By using the Keto Forest Eco Harvester head according to the thinning productivity figures, no significant difference among the tree species was detected. For the forest owner to predict the theoretical productivity of the harvester, it is possible to apply the equation R = K + KD * D, that is statistically significant, R2 =0.85. This equation is applicable to thinnings when the diameter of thinned trees is between 4 and 25 cm. Forwarder’s average productivity in thinned stands is 8.63 m**3 hE-1.