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.

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.

Resorts in the Republic of Lithuania are residential areas with natural healing factors (mineral water, healing mud, health-friendly climates, recreational areas and water bodies) and a special infrastructure enabling them to use these factors. Currently, there are 4 resorts in the country: Birštonas, Druskininkai, Neringa and Palanga. The purpose of this article is to carry out an analysis of the anthropogenic landscape of the resorts of the Republic of Lithuania in 2007-2018. 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, analytical and statistical analysis methods, logical analysis, graphical method. The analysis showed that the anthropogenic landscape of the three resorts increased: in Druskininkai – by 362.65 ha or 18.17%, in Neringa – by 113.43 ha or 52.78%, in Palanga – by 190.74 or 15.09%. The anthropogenic landscape of Birštonas has decreased by 41.11 ha or 5.03%. Over the past decades, with the intensification of anthropogenesis and its accompanying urbanization, the importance of the natural environment has become more and more understood, and landscape research, which is associated with the assessment of naturalness and its problems, is becoming more and more relevant.

Wet areas in agricultural lands are usually not fully or properly managed due to problematic accessibility by heavy machinery and are associated with lower crop yields. There are neither studies regarding spatial distribution of wet agricultural areas in Latvia nor large scale soil maps. Being aware of these wet areas, it would be possible to plan actions for effective management of these areas, starting with a scale of landscape. A geographic information system model could serve as an assistant for decision-making, such as, a direct support for the management of amelioration systems, change of land use and management patterns or granting support payments. Remote sensing data like Sentinel-2 satellite images and LiDAR (Light detecting and ranging) technology can be used to identify local wet areas. The focus of this article is to evaluate different remote sensing indices and methods that can be used to identify wet areas in agricultural lands using open access data and software. From 52 indices, which were analysed with soil moisture field measurements in 33 sample plots, only two of them showed statistical significance in linear regression model (p is less than 0.05): normalized height model in resolution of 25 meters (r2 =0.45) and visible blue spectral band in April (r2 =0.39). Results from this study help to focus on different aspects of remote sensing data usage and methodology for future improvements in order to fully implement LiDAR and Sentinel-2 data for identification of wet areas in agricultural lands.

This paper investigates the effect of fuel bias between the primary and secondary injectors of a staged fuel injection system on the performance of a high output single cylinder spark-ignited internal combustion engine. It is known that staged fuel injection systems are widely used in motorsports applications where high engine speeds are coupled with high power output, therefore, the aim of this study is to evaluate the effect of a secondary fuel injector installed on a Honda CRF450R single cylinder four-stroke gasoline engine. The said engine was equipped with a programmable Performance Electronics PE3-SP0 control unit and a secondary fuel injector identical to that of OE. Power measurements were carried out on a Dynojet-200ix chassis dynamometer in four different modes with altered fuel proportion between injectors, with each measurement being repeated three times. Ambient conditions were monitored with Performance Electronics Pe3Monitor software and the fuel map was adjusted to produce a stable air-fuel ratio. The results were averaged and compared numerically and by coefficient of correlation. It was observed that the data as obtained from the chassis dynamometer software SportDyno 4 contains a lot of noise, both mechanical and electrical in nature, and the changes in power output are highly dependent on engine and equipment temperature. The best results were obtained by using both injectors with fuel proportion biased to the front of the system.

Nowadays, with the rapid development of robotics and automation, there is a need for more powerful, more compact data processing equipment that also emits more heat. Various electronics cooling solutions are already in use, others are in development. Each cooling solution has its advantages and disadvantages. Active cooling usually dissipates heat more efficiently, but passive cooling is more reliable, especially when the electrical system is exposed to aggressive environmental influences. The possibility of using graphene in the manufacture of electrical equipment components is widely studied. Graphene could significantly improve the efficiency of passive cooling because its thermal conductivity is much better than copper.

Study has been performed in fish processing plant ‘X’ with an aim of on purpose to investigating the influence of salt treatment on yield and quality of frozen cod loins. Samples were soaked in 0.8, 1.2, 10% NaCl concentrations in brine before being frozen. In this study, the cod loin’s weight loss during refrigeration, defrosting and cooking was calculated and sensory analysis was carried out. It was found that the soaking in brines affected higher weight of cod loins after freezing. In the control group it decreased by 1.14%, but the S0.8, S1.2 and S10 groups had the weight gain, respectively 3.41, 4.72 and +4.78%. Although after the defrosting and cooking the control group had the lowest weight losses, considering the losses of all operations, it was found that the largest weight loss was in the control group and in the S0.8 group, respectively 31.19% and 31.29%, while the lowest in the S1.2 and S10 groups – 30.49 and 30.06% (p is less than 0.05), respectively. Salt treatment did not affect the taste and odour, but improved the cod loin’s texture properties. Based on these results, salt treatment is considered as an effective way to improve the yield and quality of frozen cod loins.

The aroma of coffee is the main quality factor. Compounds with floral, fruity, citrus and sometimes fermented aroma notes are defined as high quality characteristics for the specialty coffee brew. Commercial coffees mostly are at medium roast and the aroma profile is focused on balanced chocolate, caramel, toasted bread and almond bitterness aroma notes. These sensory characteristics set the focus for volatile compound profile analysis by Headspace solidphase microextraction (HS-SPME). The most popular fibres for commercial coffee aroma profile analysis are DVB/ CAR/PDMS, CAR/PDMS, PDMS/DVB and PA. There is limited research done about specialty coffee aroma profile and evaluation of more suitable fibres for solid-phase microextraction. The aim of the research is to evaluate the aroma composition of specialty coffee brews using different SPME fibres. Results demonstrated that CAR/PDMS fibre, compared to other fibres, can extract significantly more volatile compounds with higher peak areas in all chemical compound groups, except phenols. The CAR/PDMS was the only fibre which could detect all 17 important volatile compounds for specialty coffee. In conclusion, from the given research evidence, CAR/PDMS fibre is suggested as the most suitable SPME fibre coating for volatile compound extraction for specialty coffee brew import. The result provides evidence for improved specialty coffee aroma profile analysis by SPME.

The purpose of using electrosurgical devices in veterinary practice is to reduce bleeding during the cut increasing temperature locally, causing coagulation and apoptosis of proteins. There is a lack of data on the extent and depth of these thermal damages and whether these effects on the different tissues are the same. Because of that, the aim of this study was to investigate which of the different electrosurgical devices causes highest heating effect on the skin tissue of rabbits (Oryctolagus cuniculus). The research was carried out at the Latvia University of Life Sciences and Technologies, Faculty of Veterinary Medicine. It included 50 rabbits, on average 2 years old, clinically healthy, with similar weight and condition. We formed five experimental groups: skin tissue cut with CO2 laser (n=10), an electrocoagulator (n=10), a tissue welding device (n=10), a radiofrequency apparatus (n=10) and a scalpel as control group (n=10). In order to evaluate the thermal effects of electrosurgical instruments on tissues, we performed contactless thermography. There were taken 3 images for each animal, totally 150 skin thermo-grams. From the obtained results we conclude that the most pronounced thermal effect on rabbit’s skin was caused with laser and an electrocoagulator. All electrosurgical devices caused a significantly higher (p is less than 0.01) increase in skin temperature compared to a surgical scalpel at the moment of tissue incision. During the study, it was found that the gentlest electrosurgical devices were used on rabbit skin tissue were a radiofrequency device.

The necessity to increase genetic diversity in agriculture has been widely discussed during the last decades. Heterogeneous populations are one of the ways to increase genetic diversity in varieties of self-pollinating cereals. The aim of this research was to compare grain yield, its stability, foliar diseases severity and competitiveness against the weeds of spring barley (Hordeum vulgare) populations and homogenous varieties. Field trials consisting of three types of populations (simple, complex and composite cross populations – CCP) containing different levels of diversity and three check varieties were carried out during 2015−2018 under organic and conventional farming systems. No one of the populations had a significantly higher average yield than any of the check varieties. CCP1 showed a tendency to be more productive under organic growing conditions and can be characterized as widely adaptable to various growing conditions with a significantly higher yield as the average overall environments. One of the complex populations showed adaptability to favourable growing conditions and yield insignificantly higher than overall average. Other studied populations can be characterized with wide adaptability and various yield levels. For most of the populations under organic and conventional conditions, a significantly lower net blotch (caused by Pyrenophora teres) severity was observed in comparison with the most susceptible variety; infection with powdery mildew (caused by Blumeria graminis) lower than for check varieties was observed under organic growing conditions, whereas such trend was not observed under conventional conditions. All populations had a significantly lower crop ground cover and slightly lower competiveness against weeds than the variety with the best competitiveness