A research has been done on the possibility to increase the range of beer drinks by substituting hops with additives of other plants in the wort boiling process. The obtained data present evidence of the possibility of substituting hops by oak bark, yarrow, wormwood and oak acorn.

Wood construction elements are widely used in buildings and they can be used in construction elements such as roofs, floorings, windows and doors. As wood is combustible material, there are lot of fire regulations that should be fulfilled at the design stage of any building project. In Latvia, as in some other countries usage of wood in building constructions is limited. Wood materials are an ecologically friendly material and a renewable resource, and its usage should be promoted. The paper presents an overview of heat distribution in wood floorings exposed to standard heat fluxes which is different compared to wood members exposed to high heat radiation. Fire spread and self-ignition investigation on wood floorings is carried out in this research. The results show different kinds of the temperature distribution in the cross section of the wood member cross section depending on heat radiation and location of the temperature measurement point. Temperature distributions in wood during fire can be completely different in dependence on heat radiation and cross section of the wood member. The wood materials in floorings do not reach the self-ignition temperature during standard heat radiation.

This article presents the description of oak woodland key habitats and their importance in the maintaining of biodiversity as well as a necessity of management and monitoring. The lichens Lichenes and its percental cover features have been described. The exposition of lichen species depending on the cardinal points has been analysed. The article presents the characteristics of ecological indicators of lichens in the objects. The lichenoindicative evaluation and comparison of oak woodland key habitats in Latvia have been carried out.

The objective of the studies was to evaluate the suitability of sand reed filter for the treatment of wastewater from milk collection post and on the basis of the studies performed to determine the minimal length of filtration path in order to reach the normative wastewater treatment level. In 2003, in Padargupiai village (Ariogala municipality, Raseiniai district) experimental treatment facilities for wastewater from milk collection post were constructed. As the pollution of such wastewater after pre-treatment (primary treatment) is 2 times higher than that of domestic wastewater, the filtration path in constructed wetlands was made 2 times longer (up to 10 m long). On the basis of the study results the dependence equations were made, with the help of which the amounts of the main pollutants contained in wastewater of milk collection posts were calculated, after the wastewater is filtered through the sand layer of different length. As calculations have shown, the treatment of wastewater from milk collection posts until the allowable rates depends on the constructed wetlands with the length of the filtration path of 7 m. The removal of organic pollutants, total nitrogen and total phosphorus from wastewater flowing through such media are 97.2%, 68.7%, and 91% respectively. The studies performed allowed to improve the calculations of the necessary area of constructed wetlands in order to reach the normative treatment level of wastewater from milk collection posts according to the index biochemical oxygen demand (BOD5).

Basing on the economic, ecological and social points of view, the polder systems in the Nemunas lowland are considered as unique, requiring a great deal of annual state subsidies. According to the land-improvement programme, during the period of 2006-2008, Lithuanian polder system are planned to be yearly granted 2.15 million euro from the State budget, whereas the local administration of Silute district, which is exploiting the polders of the Lower Nemunas - more than half of the sum (63%). The article includes the analysis of exploitation expenses and statistical estimation of the Lower Nemunas' polders during the period of 1996-2006 as well as the investigation of the funds distribution on routine repairs, reconstruction and maintenance work. The average annual expenses on the pump stations, dikes, ditches and roads during the research period were determined. The analysis of the previous decade's expenses shows that the statistical average of the expenditure on the polder systems of Silute district amounts to 0.68+-0.13 million euro a year. The yearly renovation of polders depreciation should be obviously awarded a grant of the amount not less than 0.72 million euro.

On the basis of this research and the investigations of other authors (1992 - 2002), the paper presents the comparison of the treatment efficiency of domestic wastewater treatment facilities functioning by different natural means. From all the studied three natural wastewater treatment facilities, constructed wetlands are considered as most efficient for domestic wastewater treatment: here the removal of organic pollutants and biogenic compounds is 85-98% and 67-95% respectively. Biological ponds are most suitable for the treatment of domestic wastewater, the discharge and pollution of which is fluctuating within a wide range. However, such ponds do not always ensure the treatment until the allowable rates. Their treatment efficiency according to biochemical oxygen demand (BOD5) is 49.6%. Total nitrogen amount contained in wastewater outflow from the treatment facilities with biological ponds was on the average 22.2 mg lE-1. The biggest problem of those ponds is rather low P removal efficiency (only 29.5%). Therefore wastewater flowing out of the ponds needs additional treatment. The usage of subsoil filtration fields is limited because their arrangement requires light soils. When arranging the distribution pipeline below the freezing zone, in many places the requirement that the pipes must be 1 m above the maximum ground water level is violated. The pipes should be arranged in places where there is no recipient for treated wastewater outflow. The load of subsoil filtration fields should not exceed 300 m**3 haE-1 per month. From the economical point of view, domestic wastewater treatment facilities with flowing ponds require least expenses.

The paper deals with the analysis of ground water quality when slurry is applied on crop rotation fields. The investigations were carried out in Juodkiskis study object of the Lithuanian Institute of Water Management in 1995-1998. According to the average concentrations, the quality of ground water samples taken from the borehole arranged in Juodkiskis test field was good compared with hygienic rates for drinking water. All samples taken for the estimation of ammonia and nitrate nitrogen amount were of good quality. However, nitrate-N concentration increased to 5.5-5.6 mg lE-1 in some periods. Having compared actual phosphate phosphorus concentrations with the allowable ones it may be confirmed that ground water is not polluted with phosphates as phosphate phosphorus concentrations did not reach P-load permissible for drinking water. Considering the correlation connection between ground water level and chemical compounds concentrations, it was determined that ammonia nitrogen and phosphorus compounds concentrations were influenced by ground water level fluctuations (correlation coefficient r = 0:54 and r = 0:62). (Given r values correspond to the reliability criterion tactual is greater than ttheor95%). Lower ground water levels in a borehole determine higher N - NH4**+, P - PO4**- and Ptotal concentrations. No relation between nitrate nitrogen (N - NO3**-), Ntotal and K**+ and ground water level fluctuations was determined.

At rural enterprises, besides the traditional resources - natural, financial, and human capital - there is some other kind of capital - it is social capital. Foreign scientists have done a lot of researches on it. The nature of social capital and its role in economics is not much studied in Latvia. The present scientific article reflects consumptions on social capital by different foreign scientists. The World Bank as an institution has also approached to the research of social capital. It studies social capital at institutions. The World Bank describes the social capital of two kinds. The scientific article characterizes Pieriga region. Rural enterprises and businessmen of agricultural, industrial and service branches in Pieriga region have been enquired. By the results of the enquiry, the presence of social capital in rural enterprises and its impact on their development have been analysed.

In 2003 and 2004, field experiments with spring wheat (Triticum aestivum L.) were carried out at the Lithuanian Institute of Agriculture in Dotnuva, Lithuania. The aim of the study was to evaluate the effect of nitrogen and sulphur fertilizers on tiller formation and grain yield of spring wheat (variety 'Munk'). N and S fertilizers were applied at 3 rates: N (0, 60 and 120 kg haE-1) and S (0, 15 and 30 kgE-1 ha). Both years, N fertilization had a significant effect on tiller formation. At harvest, the total number of tillers was approximately 0.5 tillers higher in the plots with the application of N120. The growing season in 2003 was comparatively dryer, and a significant increase in grain yield was found - up to 60 kg haE-1 of N. Due to higher rainfall in 2004, grain yield was much higher and the highest effect was found with the maximum N supply - 120 kg haE-1. One thousand grain weight was influenced by the year, while fertilizers did not have any significant effect. The impact of S fertilization on the number of tillers and final grain yield was insignificant; nevertheless S fertilization increased the concentration of S in the aboveground plant mass.

Turkey has rich inland water sources, about 200 natural lakes, about 750 artificial lakes or ponds, about 193 reservoirs, 33 rivers and streams of 177,714 km length and 8333 km of coastal strips. Some lagoons covering of 70,000 ha in Aegean and Mediterranean coastal strips are very suitable for aquaculture. The main fish species cultured in Turkey are carp (Cyprinus carpio), rainbow trout (Oncorhynchus mykiss), Atlantic salmon (Salmo salar), gilthead sea bream (Sparus aurata), European sea bass (Dicentrarchus labrax), bluefin tuna (Thunnus thynnus), Blackl sea turbot (Pselta maxima), Mediterranean mussel (Mytilus galloprovincialis) and shrimp (Penaeidae spp). Aquaculture production of Turkey has grown steadily over the years from 5,782 t in 1990 to 63,000 t in 1999 and to 79,031 t in 2000. There are 1309 farms in inland water producing approximately 32,466 t of fresh water fish species and 352 farms at sea producing 40,119 t of sea fish species, mainly Gilthead sea bream and European sea bass.