One of the primary reasons for expanding the production and use of biofuels is the potential environmental benefit that can be obtained from replacing fossil fuels with fuels derived from renewable biomass resources. This investigation examines the impact of biofuels on the environment directly from the practical view point analysing how the internal combustion engine emission concentration changes using the most common first-generation biofuels in Latvia – biodiesel, rapeseed oil and bioethanol. Laboratory experiments were performed on a chassis dynamometer Mustang MD1750, but the content of exhaust gases components was determined by the AV L SESAM FTIR measurement system. Investigation shows that the trends of different exhaust gas component changes, which would be the same for all investigated fuels, don't exist, i.e., each vehicle and biofuel type or blend is particular and has to be analysed separately. In comparison with fossil diesel, running the car VW Golf on rapeseed oil the average reduction of NOx was 10%, but SO2 – 59%. The CO, CO2, unburned hydrocarbon and mechanical particle emissions were higher. Running the car Opel Vectra on biodiesel the amount of NOx in comparison with fossil diesel increased in average by about 12%, the amount of mechanical particles and unburned hydrocarbons decreased quite significantly, but just a small increase of CO and SO2 was observed. Testing the car VW Passat on gasoline-bioethanol blends increase of the bioethanol content in the fuel blend increased also the NOx content in exhaust gases, but the content of CO, CO2 and NH3 decreased.

Three spectrophotometric methods were compared for the assessment of milk fat oxidation: the AOCS (American Oil Chemists' Society) 2-thiobarbituric acid (TBA) value direct method, the TBA method of Aristova, and the modified method for the estimation of total carbonyl compounds in oils of Endo et al. Two cow milk fat samples – a fresh fat, obtained from fresh milk, and a rancid fat, obtained from a rancid commercial butter by means of high-speed centrifugation (15.871 × g, 30 minutes at 40 deg C) – were analyzed several times in a 22-day period after sample preparation. A positive linear correlation between absorbance and storage time was established in all used methods. The method of Aristova is appropriate for exact determination of oxidation products. This method had rather good R2 value (0.85) of the fresh fat sample results; however, the coefficient of variation (45.78%) showed rather large deviations between parallel analyses. The methods of AOCS and Endo et al. can be used for the assessment of the dynamics of fat oxidation by reporting absorbance values from the assay directly. By these methods rather high R2 values (0.86, 0.93) of the fresh fat sample results were obtained; the coefficients of variation also were satisfactory (10.13%, 11.12%). The last two methods are cheaper and require smaller sample amounts (less than 0.2 g), while the method of AOCS is the most time-consuming method.

Nowadays one of most urgent problems is the production of healthy food which ensures normal maintenance of the human body. Rye bread is one of the bases of wholesome food. Every year scientists in Europe and other countries carry out investigations on the nutritional impact of processing rye. Interesting questions arise regarding changes in the biologically active compounds in rye bread as a result of processed. Connate antiradical activity (ARA) of rye bread affects free radicals by scavenging or donating electrons, which suggests that the ARA of rye bread averts attacks of free radicals on human cells. Therefore it is important to use antioxidants containing products with antiradical activity in human diets. The aim of this study was to analyse the impact of baking processing on rye bread antiradical activity. The object of the study was Latvian traditional rye bread baked in a commercial bakery, made with scald, and baked in a clay-floor firewood oven. The antiradical activity of rye bread crumb and crust was measured by using free radical 2.2-diphenyl-1-picrylhydrazyl (DPPH). It was concluded in the research that rye flour type 1740 has antiradical activity by scavenging 67 μmol·100gE-1 DM of the stable free radical DPPH, which is 13% more than the dough antiradical activity of the same flour. The antiradical activity of the crust is 49.6% more than the antiradical activity of the crumb. Baking time has no significant impact on changes in the antiradical activity of rye bread crumb.

The content of carbohydrates (fructose, glucose, and sucrose) and organic acids (citric acid, succinic acid, malic acid, sorbic acid, and ascorbic acid (vitamin C)) in organically grown vegetables (carrots, parsnips, celeriacs, and red beets) and dried vegetable products were analyzed by the HPLC reverse phase and ion exchange methods. The main carbohydrate detected in fresh vegetables invariably was sucrose (1.29 – 11.17 g 100 gE-1). Fructose and glucose were found in similar ranges (0.09 – 2.47 g 100 gE-1, 0.14 – 3.02 g 100 gE-1 respectively). A similar distribution of carbohydrates was determined in dried products. The highest fructose and glucose contents were found in fresh carrots - 2.47 g 100 gE-1 and 3.02 g 100 gE-1 respectively; but in dried carrot products – 14.53 g 100 gE-1 and 15.43 g 100 gE-1. High amounts of sucrose were found in red beets: 11.17 g 100 gE-1 in fresh samples, and 48.50 g 100 gE-1 in dried products. Malic and citric acids were detected as the main acids of fresh vegetables. Highest citric acid amount was in red beets (266.19 mg 100 gE-1), whereas celeriacs and parsnips had a high malic acid content. The results from this study demonstrated variability and concentration range of carbohydrates and organic acids, wherewith the organoleptic profile of the products. Dried products are considered as a good source of energy.

Both the rowanberries (Sorbus) and the chokeberries (Aronia) belong to the family Rosaceae. The berries of these cultivars are suitable for production of health-food products. The main components in the dry matter of fruits are carbohydrates, primarily sugars. The aim of this experiment was to determine the content of simple sugars and sorbitol in different fresh rowanberry cultivars and chokeberries and to compare the composition of these compounds after freezing and thawing of berries. The experiments were done in the Customs laboratory of the National Customs Board, State Revenue Service (Latvia). The rowanberries were picked in the Pure Horticultural Research centre, and black chokeberries were obtained from farm 'Ceplīši' (rural municipality of Pure). The contents of dry matter and soluble solids were analyzed in fresh berries, and the contents of sugars and sorbitol were analyzed both in fresh berries and in berries after freezing and thawing of 13 different cultivars of rowanberries and one black chokeberry. For determination of the soluble solids content, the refractometric method was used, and for determination of the glucose, fructose, sucrose and sorbitol content, high performance liquid chromatography was used. The results showed that rowanberries and chokeberries contained 3.24-7.24 g 100 gE-1 of sorbitol which was the dominant compound in all investigated berries. The highest content of sorbitol was found in the wild rowanberries and rowanberries Sorbus aucuparia var. sibirica, but fruits of rowanberry×pear 'Alaya Krupnaya' contained the least content of sorbitol. After freezing and thawing of berries, the content of sugars and sorbitol were decreased by 5-23% with some exclusion.

The aim of this paper is to evaluate all kinds of experiences with attractive EU funding for Latvia's private forest sector in the past and to generate new proposals for effective acquisition in near future. Latvian institution may learn from these experiences in order to improve their (acquisition) role in project proposals for the private forest sector. Consequently, the relatively underdeveloped Latvian private forest sector will get its highly needed support for better performance, and progress towards other, leading EU forest sectors. The possibilities for attractive financial EU support are reviewed through both historic experiences with the EU's 'Rural Development Program for 2007 – 2013' and the EU grants, designated for forestry projects. An extensive round of interviews is held with state forest owners and experts involved in forest management programmes and other dedicated EU forest funding initiatives. Following the expert interviews, two key indicators are developed to evaluate the support from the EU. Contacts with the EU countries (the Netherlands, Belgium, Finland and Poland) where similar forestry activities have been done as in Latvia were made. Research done in this work is unique as according to the author's information these countries do not have similar research related to the EU funds efficiency and Rural Development Program for 2007 – 2013. The successfulness of Latvian applications for the EU funding is one major indicator for further fund raising. The EU supported investments generally have higher economic results in comparison with their non EU funded counterparts.

Reduction of agricultural production has led to abandonment of farmlands in Latvia. According to the Central Statistical Bureau, 1.4 million ha of lands, including 0.6 million ha of farmlands were set aside in 2008. Most of them transform into forests; however, information about the afforestation has been limited until recent years. The first field measurement based evaluation of forest stands on abandoned farmlands was implemented within the scope of the National statistical forest inventory (NSFI). The NSFI covers forests, farmlands, settlements, wetlands and other lands, providing valuable information about the land use and forest resources. According to the NSFI, total area of naturally afforested farmlands is 257,850 ± 3,606 ha with growing stock of 2,870.364 ± 239,088 m³. Naturally afforested lands occupy 4% of the total country area. The highest share of naturally afforested lands is in Ludza (11% of the total area) and Krāslava districts (9% of the total area). Birch (Betula pendula Roth) and grey alder (Alnus incana (L.) Moench) are the most common dominant tree species in naturally afforested areas (77,092 ± 1,861 ha and 40,285 ± 1,395 ha, respectively). In relation to the Kyoto protocol it is important to separate lands afforested before and after 1990. The total area of lands afforested after 1990 in Latvia is 170,890 ± 2,862 ha with total growing stock of 1,367.427 ± 125,482 m³ and annual increment of timber volume – 122,530 ± 10,513 m³.

One of the key factors affecting the formation of high-quality forest is thinning. Latvia's yearly budget of commercial thinning is not met; therefore, there are plenty of forests which are not thinned as planned and this leads to declining quality of forest stands. The timber processing industry needs significant excluded volume of timber, but forest owners are unable to maximize profits in future. Extensive logging of commercial thinning is hindered by economic factors and forestry regulations. Logging business is not satisfied with the productivity indicates and restricting forestry and environmental laws. The world's leading forest engineering firm offers a variety of forest harvester design and structural solutions. The first real use of commercial harvesters in commercial thinning in Latvia's conditions revealed several problems. The most important one is how to increase harvester productivity, while ensuring the quality of residual stands. To increase effectiveness of the logging machines and the proportion of commercial thinning, it is necessary to explore main factors affecting harvester productivity. This work aims to clarify the main pressures hampering harvester productivity and evaluate the quality of remaining trees in commercial thinning in Latvia. The main results are that during night productivity of harvester decreases by 12%, while marking trees to be cut down with fluorescent colour increases productivity of harvester at night by 15%. Productivity of harvester in thinning depends on average volume of harvested trees. These results of the work were obtained through various experiments on twelve different commercial thinning areas in Latvia.

The effect of growing conditions, age and stocking density on the amount of deadwood in the pine forest stands of Latvia was analyzed in this research. The material for studies was collected within the framework of the National Forest inventory of Latvia in the period 2004 to 2008. From databases of the National forest inventory the data about 1627 sample plots dominated by pine were selected and analysed. The total amount of deadwood (m3 haE-1) was compared among five forest edaphical rows - forests on dry mineral soils, forests on wet mineral soils, forests on wet peat soils, forests on drained mineral soils and forests on drained peat soils. Deadwood was also analysed in five age groups – young, middle age, premature, mature and over-mature stands, as well as in six groups of stocking density – small-density, sparse-density, middle-density, high-density, full-density and over-density stands. It was found out, that the growing conditions (p = 0.000 is less than α = 0.05), stand age (p = 0.000) and stocking density (p = 0.000) have significant influence on the amount of deadwood in pine forest stands. The highest amount of deadwood is in the pine stands on wet mineral soils – 18.6 ± 2.09 m3 haE-1. With increase of the stand age the amount of deadwood also increases and in the mature pine stands the amount of deadwood is 17.8 ± 1.58 m**3 haE-1. The amount of deadwood in the pine forest stands also increases with stocking density and in the over-density stands it is 21.6 ± 2.50 m**3 haE-1.

The urban forest is recognized as a potential to improve the quality of life of urban dwellers and increase the sustainability and ecological stability of the city. However, there is little data on professional attitude to urban naturalistic landscapes. This research studies the attitude of professionals and decision makers to the naturalistic forest landscapes in urban area of Riga city, Latvia, in contrast to more traditional – formal landscape. The survey includes the opinions of territorial planners and environment specialists from Riga municipality and other institutions related to ecological, practical, planning and conservation activities, and private working landscape architects. The statistical analysis and data’s empirical distribution showed that professionals in Riga city recognize the values and benefits of naturalistic forest landscape. However, environmental preferences may depend more on affective reactions than on ecologically-based logical operations.