The majority of natural Lithuanian rivers were regulated during intensive land reclamation period. Straightening of rivers caused unfavourable conditions for biodiversity. Four tributaries of the Merkys River in the South Lithuania were selected to explore changes in biodiversity patterns and determine the relationships between flow energy distribution in beds and ecological status of selected rivers. The research has shown that variation of cross sections area was usually 1.2 to 2.3 times higher in natural beds as compared to regulated ones. The range of rivers flow energy, estimated by Froude number, values were characterized as higher in natural (0.0 to 0.35) streams than in regulated (0.0 to 0.20) ones. This is the reason why the biggest number of macroinvertebrate taxa during the research period was recorded in natural riverbeds and the lowest - in the fields of the regulated segments. The assessing the abundance of fish revealed that total fish density in natural river sections was four times higher than in regulated ones. The research has approved the importance of naturalness for biodiversity and rehabilitation of regulated rivers in Lithuania.

The most efficient way to dewater sewage sludge is the thermal drying, which simultaneously with the granulation allows obtaining the product in the form of granules, being a non-putrescible fertilizer that is also easy for transportation, storage and bringing into soil. When large volumes of sewage sludge are formed, which are unfit for use in agriculture, application of other utilization methods, such as burning, would be purposeful. The aim is to determine the optimum drying modes of sewage sludge with application of pneumatic pulse method at treatment facilities in the pilot project. To do this, it is necessary to develop a proposal for the design of operating model. The design and making of working model is necessary to determine the optimal conditions for sewage sludge drying at sewage disposal works. The drying process is provided to be realized in a closed-loop cycle (without emission into atmosphere). Due to inner recirculation of dry air, the installation heat consumption is reduced. Calculations have shown that there is economic expediency of using the pneumatic pulse method in sewage sludge thermal drying technology and possibility of using sewage sludge as an alternative fuel. Optimization of sewage sludge thermal drying process with the use of pneumatic pulse method will considerably extend the perspectives for utilization and further use of sewage sludge.

The main objective of this research is to find out if quantitative factors describing agriculture have a statistically significant role on the parliamentary election results in Latvia. If this statistical relationship can be proven, then it is important to interpret the causality behind it. 18 agricultural indicators from the 2001 Census of Agriculture were selected to be analyzed with the 8th Saeima political party election results by using multiple linear regression analysis. These 18 parameters are different in their character, and they describe the size of farms, level of education for farmers, land usage statistics, proportion and productivity of certain crops, livestock and the usage of farm machinery. The main hypothesis of this research was that the rural civil parishes with a high intensity of agriculture have a statistically significant difference in election results when compared to the rest of the election results in Latvia. Initial results showed a strong correlation between election results and agricultural indicators, but when the ethnic factor was taken into account in the linear regression model the role of these agricultural indicators was greatly diminished.

The positive place image attracts investors, foreign and national guests, creates the local residents’ pride and distinguishes it form the competing locations. Project activities are completed/or being carried out under the funding of the European Union and the Republic of Lithuania. The research problem: do project activities form positive place image? The research object – place image formation carrying out project activities. The purpose of the article – to analyze the implemented projects by Silale district Municipality and investigate their impact on the location image formation in Silale district. Research objectives are: (1) to identify and investigate the factors impacting the formation of Silale district Image; (2) to analyze and assess the project activities performed by Silale district Municipality. For the research completion the methods of questionnaire survey and content analysis were applied. The gained research outcome has disclosed that project activities in Silale district are focused to the restoration and beautifying of environment, but not on the investors, and there are not carried out any investment attraction projects. Two segments – local residents and tourists – received the benefit from the project activities in Silale district.

Pear (Pyrus communis L.) fruits in Latvia are very popular, although orchard areas are not large. In the commercial orchards the control of plant pathogens mainly is performed using a plant protection plan, based on long-term observations. European pear rust caused by Gymnosporangium sabinae (Dicks.) G. Winter has become during recent years one of the most important diseases in Latvian pear orchards. Pathogen G. sabinae has a complex development cycle, with four types of spores on two different plants: pear and junipers. Favourable development of each stage depends on the specific environmental conditions. The aim of the study was field evaluation of the disease severity depending on agro-ecological factors. The study was performed at the Latvia State Institute of Fruit-Growing from 2008 to 2012. The severity of European pear rust infection on leaves of cultivars was evaluated in points 0–5, where: 0 – a tree has no infected leaves; 5 – 81% to 100% infected leaves. The disease severity during these years, impact of tree planting year, rootstock, cultivar and tree location in the plot were analyzed. Results gave the opportunity to determine which factors have positive influence on the development of pathogen and severity of disease. Severity of disease was not directly dependent on cultivar, their country of origin, rootstock and planting year. Severity of disease was influenced by tree location in the orchard; higher severity was observed on larger and more vigorous trees, located in outer rows, exposed to the prevailing wind carrying pathogen spores.

Plants are components of ecosystem that transfer elements from abiotic to biotic environments. Several elements, such as As, Cd, Hg, Pb, can be considered as food chain contaminants. Simultaneously, some essential micronutrients (e.g., Cu, Cr, Ni, Zn) at high concentrations may become toxic to both, plants and animals. To secure the aim to describe the uptake of metals by food crop species such vegetables, as radish Raphanus sativus L., leafy lettuce Lactuca sativa L. and dill Anethum graveolens L., were grown in soils of various grading composition and type. There were five soil types selected. A part of soils was contaminated with copper sulphate solution at different target concentrations, while another part was contaminated with mixture of metal (Pb, Cd, Cu, Zn) compounds. In half of treated soil samples the solution of humic substances was added. Harvested vegetables were dried, and after wet digestion with nitric acid quantitative analysis of metal concentrations was performed by use of atomic absorption spectrometry. The highest concentration of copper was detected in vegetable samples grown in soils with less organics, thereby indicating the importance of soil organic matter to metal transfer routes and accumulation rates in plants. Analysis of lettuce grown in soils contaminated with the mixture of metal compounds revealed that zinc was a metal absorbed more intensively, but metal uptake and accumulation was less intensive from peat if compared with other soils.

The main purpose of the present experiments was to investigate the effect of various hydrogen peroxide (H2O2) concentrations and for various lengths of treatment on the total carotenoid, β–carotene content, colour intensity and microbiological safety on the fresh shredded carrots. Shredded carrots were dipped in 0.5, 1.0 and 1.5% H2 O2 water solution for 30 ± 1s, 60 ± 1s and 90 ± 1s. Negative effect of H2 O2 on β–carotene content and colour parameters of analyzed shredded carrots samples was not detected. In carrots treated with H2 O2 (p = 0.008) for 60 – 90s the total content of carotenoids significantly decreased during treatment compared to untreated carrot samples. There was significant difference (p is less than 0.05) observed between treated and non–treated shredded carrot samples on the total bacteria count. It was possible to reduce significantly (p is less than 0.05) the content of yeasts and mould up to 99.99% by shredded carrots treatment with 1.5% hydrogen peroxide water solution for 30 ± 1s. In the non–processed carrots E.coli was detected; however, it was possible to destroy E.coli by treating carrots with 0.5% H2 O2 water solution for 30 ± 1s. Considering all experimentally obtained results, we have concluded that fresh shredded carrots could be treated in water with the addition of hydrogen peroxide 1.5% for 30 ± 1s to maintain quality.

Horseradish (Armoracia rusticana L.) is a perennial herb belonging to the Brassicaceae family and contains biologically active substances. The aim of the current research was to determine the most suitable extraction method and solvent for obtaining horseradish leaf extracts with high antiradical activity. For experiments fresh leaves of horseradish were extracted with seven different solvents: n-hexane, diethyl ether, 2-propanol, acetone, ethanol (95%), ethanolwater/acetic acid (80/20/1 v/v/v) and ethanol / water (80/20 by volume) using two extraction methods (conventional and Soxhlet). For all extracts, total phenolic, flavonoid content and DPPH˙, ABTS radical scavenging activity, and reducing power were determined using a spectrophotometric method. As the best solvent can be used ethanol. Total phenolic content and total flavonoid content was higher in Soxhlet extracts. Comparing to other plants, the proportion of flavonoids in the amount of total phenolics is average, and it increases by increasing the polarity of used solvent. It can be concluded that by using Soxhlet extraction method it is possible to obtain extracts that are effective antioxidants. A very strong and a strong correlation has been identified between levels of phenolic compounds and antioxidant capacities of the extracts.

Nutritional value and shelf life of milk and dairy products depend on the composition and stability of their constituents. The aim of the present study was to evaluate the effects of carrots as cow feed carotenoid source on butter oil fatty acid (FA) composition and oxidative stability. Milk was obtained from one trial group (TG; n=5) and one control cow group (CG; n=5) in a conventional dairy farm in Latvia. TG cows received carrots 7 kg per cow per day; the length of the supplementation period was 39 days. The stability of butter oil exposed to sunlight (3h) and held for 14 days in the temperature of 60 °C was analyzed by peroxide value method. The changes of the FA content and ratios in TG milk fat were more positive with respect to the fat nutritional value as observed in CG – stronger increase in the content of polyunsaturated FA (p is less than 0.05), and in the ratio between stearic and palmitic acids (p is less than 0.05); also a tendency was seen of increasing content of short and monounsaturated FA, as well as decreasing the ratio between ω6 and ω3 FA groups. Oxidative stability of the carrot supplemented cow group’s milk butter oil samples that were collected after 25- day trial period, exposed to sunlight (3h) and stored at a temperature of 60 °C was significantly (p is less than 0.05) higher compared to CG samples. After the 39-day long trial period stability difference was not significant, despite the tendency that average polyunsaturated FA content in TG samples was higher compared to the control.

In modern life oxidative stress has a serious effect on human health; therefore, natural antioxidants play an important role in human well-being. Hen (Gallus gallus domesticus) eggs can be effectively enriched with selenium and vitamin E and can be used as a source of natural antioxidants. The objective of this study was to determine the interaction of selenium and vitamin E in eggs and egg yolk oil. Two groups of Lohman Brown-Classic breed laying hens from a real production facility were taken as an experimental object. The basal diet was the same for both groups and content 25 mg kgE-1 of vitamin E added. 0.2 mg kgE-1 of sodium selenite was used as an inorganic source of selenium in feed for one hen group and 0.3 mg kgE-1 of organic selenium in the selenized yeast form for the other group. The selenium content was determined in eggs, egg yolk, egg white and egg yolk oil samples and vitamin E content in egg yolks and egg yolk oil. The results of this study indicate that there is no difference in selenium content in eggs from inorganic and organic selenium hen diet taking into account that selenium content in feed was different. The majority of selenium is located in egg yolk, but there was no selenium detected in egg yolk oil. Vitamin E content in egg yolks was not affected by the source of selenium (p is less than 0.05). High vitamin E content in egg yolk oil effectively protects egg yolk oil from oxidation during storage.