Root rot caused by Heterobasidion spp. is one of the most important pathogens in Norway spruce (Picea abies (L.) Karst.) stands in Latvia. It is estimated that in Latvia on average 22.9% of Norway spruce stumps are infected with Heterobasidion spp. The aim of this study was to compare four different electronic devices for Heterobasidion root rot detection in Norway spruce. In the autumn of 2009, in a sample plot located in the forests of Kalsnava district 27 trees were used to compare the possibility of instruments to detect root rot. The results show that IML-RESI F400 accuracy for detecting root rot in Norway spruce is high and the instrument is usable for detecting root rot, but additional accumulators are needed for large sample plots. Rotfinder’s accuracy for detecting root rot varies from probe to probe taken from one tree. Conditiometer AS-1 and Arbo-Sonic decay detector show slightly higher average values for infected trees, but the difference for both instruments between healthy and decayed trees is not significant, thus leaving the usage of instruments questionable.

Small diameter wood obtained from young stand tending, with average d1.3 is greater than 4 cm, is suitable for the production of biofuel. So far mainly hand motorized tools have been used in young stand tending, to gather the small -diameter wood is costly and unprofitable. As the technology evolves and labor costs rise studies are carried out on how to increase the profitability of the young stand tending, by applying mechanized tending and production of biofuel from small-diameter wood. The study analyzed indicators, which directly affect the profitability of biofuel production from small-diameter wood produced by harvester tending. The biofuel production costs are analyzed using average purchase price of wood chips production service paid by JSC ‘Latvijas valsts meži’ (further JSC LVM). Revenue related to sales of chips is analyzed on the basis of JSC LVM average sales price for wood chips. The price of the preparation of the small-diameter wood is high and the proportions of the full cost price of wood chips make up 38%. The price of forwarding service impact on the full cost price comprises up to 25% and depends on the forwarding distance. The profitability calculation shows, that production of wood chips from the harvester tended young stands has to be regarded as unprofitable.

To forecast how different indices describing Latvian forest industry will develop in the future, the decision support program which is based on the research of supply chains and production processes as well as on systematic analysis of the whole industry should be developed. One of the most common types of analysis is modelling of processes. In this paper processes of forestry and wood processing in Latvia are modelled by using general approach for system modelling, and each process is described as an abstract system where only its input and output values were identified. Correlations of input and output value time series with a simple and multiple regression analysis method were analyzed. Regression analysis was created for 77 pairs of indices which theoretically could have significant correlations. Input and output factor linear regression analysis for set of processes Forestry and Wood processing shows that not always there is significant correlation between time series of chosen model factors. Some of correlations between time series of input and output data in the model of forest sector even showed controversial results. The amount of information about processes and their quantitative indicators in Latvian wood processing industry is not sufficient for development of precise simulation models. There is need to develop a list of criteria for missing information and carry out its collection process.

The furniture industry is an innovative industry that produces high added value products and its turnover is several billions of Euros in Europe, and there mainly work small and medium-sized enterprises (abbreviation – SMEs). Nowadays competitiveness is an essential factor for both a country and its enterprises in the process of dealing with changing market conditions. The global market is changing and for enterprises it is too hard to position themselves and find the way how to differ from other competitors. From 2006 until 2010 a Latvian furniture market value, numbers of employees and enterprises in the sector and its share in GDP has decreased. As a result, there are the serious challenges to be met and increase their competitiveness in domestic and export markets. The author has made an in-depth research into influencing competitiveness factors of SME micro level in the furniture manufacturing industry. The study objective was to identify the key internal factors which influence the SME of Latvian furniture manufacturers. The aim was to obtain an internal factor of competitiveness assessment of the 30 respondents by random sampling method and expert method of factor assessment. The enterprises need to constantly increase their competitiveness. The internal factors influencing the competitiveness of SMEs are connected with the products, manufacturing of products, financial situation, management and marketing activities. The competitiveness level of Latvia`s SMEs in the furniture manufacturing has been evaluated as average in 70% of cases. Only 27% of the enterprises show a good level of competitiveness.

Machining of wood of soft deciduous trees is currently based on the knowledge about cutting of wood of hard deciduous and coniferous trees and has not developed a comprehensive research methodology of cutting processes. Therefore, the objective of the study is a development of methodology for longitudinal sawing with circular saw and straight milling that would be utilized with a purpose of acquiring further knowledge on wood cutting and the improvement of cutting tool designs. Sub-objective of the study is determination of duration of cutter’s wear periods when using developed methodology. For the purpose of solving problems regarding cutting process of soft deciduous wood, the optimization of cutting tools and cutting modes were carried out in conditions that comply with the tendencies of the practise. The cutting process was carried out by a computer numerical control machine and the data acquisition by electronic measuring instruments. Aspen (Populus tremula L.) wood was used for wood samples. The methodology was developed for sawing, which complements the authors previously described methodology of the milling process investigations. Initially, only the results of periods of cutter wear and cutting velocity effects on these periods when milling process is used were obtained. It was concluded that the methodology can be used for further investigations and the critical wear period begins two times later when cutting velocity increases twice.

There are about 3,000-4,000 heavy metal contaminated sites across Lithuania. According to Lithuanian legal framework, the only way to manage this pollution is ex-situ cleaning which requires excavation, transporting, storage place and later monitoring. This indicates the urgent need of innovative technologies that would be not only costeffective but also environmentally friendly and have a public acceptance. Such technologies are natural and chemically enhanced phytoextractions. Both technologies incorporate plants that can accumulate excessive amounts of heavy metals. During continuous phytoextraction plants accumulate heavy metals throughout all vegetation period and are harvested together with heavy metals when desired biomass is gained. At chemically assisted phytoextraction metal binding chelates are added to increase heavy metal uptake by plants. Since phytoextraction is considered as promising green technology, many efforts are laid to find the most suitable hyperaccumulator plants as well as ecologically safe chelating agents. This paper intends to overview latest researches done at phytoextraction field and look over this kind of remediation possibilities in Lithuania.

The research topic is sensory, healing, rehabilitation and horticultural gardens, and the related discourses. The first part of the paper describes the historic development of the rehabilitation and health gardens in Latvia. Then he research paper takes a look at the main aspects which dominate in the rehabilitation and sensory visual and functional garden sites in the world. The quest to create contemporary landscape sites for health reasons is still one of the main subjects to explore and find definitions for. The methodology used in this paper is descriptive, from the perspective of historical relaxation gardens and health sites. The aim of this research is to define the main development lines of health sites in Latvia, trying to answer such questions as: How we can start developing sensory gardens and what is needed for their development in the future? To achieve the goal, it is necessary to absorb the world experience and exchange best practices, find innovative solutions, and adapt advanced rehabilitation center area landscapes to individual needs. When creating the healing gardens, the aesthetic and functional criteria have to be applied. Depending on the availability of the natural environment, health and satisfaction will be enhanced.

Timber structure is a very complex system with its own specific character that causes a lot of difficulties for designers to predict its precise behaviour under loading. Timber construction behaviour under load is affected by many factors that in most cases influence timber constructions in a negative manner. Part of these influencing factors are properties of material, the other are components of the environment where the timber construction is located. This paper presents the results of experimental research where seventeen softwood (Pinus sylvestris L.) timber beams of rectangular cross section were tested in four point bending under long-term load in uncontrolled microclimate conditions (unheated building, all year round weather in the region of Latvia). Values of mechanical properties (modulus of elasticity), physical properties (density, amount of latewood, number of annual rings in 1 cm of wood) were measured at the start of the test; while monitoring of moisture content of wood, relative humidity and air temperature were performed simultaneously for the whole period of test. It has been observed that the main factors that significantly influence timber beam behaviour during period under load in natural climatic conditions are modulus of elasticity (MoE), density of wood and number of annual rings per 1 cm of wood. Amount of latewood showed an insignificant impact on timber beam behaviour under load.

In this paper regression analysis was adopted to assess the wind-wave relationship between wind speeds and wave heights on the Lithuanian coast of the Baltic Sea. In the coastal observations register missing data of visual wave observations occur because of the fog, ice, evaporation or other meteorological phenomenon. There is also inconsistency in instrumental measurements of wave heights in the Lithuanian coast due to technical issues. First step to fill the gaps in the wave height data is to find a strong relationship between wind speeds and wave heights. In this study correlation coefficients for Nida and Klaipeda coastal hydrometeorological stations data both taking and not taking into consideration wind blowing directions were calculated. Every data set used in this study was treated separately and it was revealed that applying nonlinear regression the most common model for wind-wave relationship analysis on Lithuanian coast is DR-Hill model, while applying multivariable regression it is Full Cubic model. Relationship between wind speeds and wave heights always can be improved by removing swell waves from correlation.

The article presents the natural and regulated stream bed stability and self-regulation issues. River beds equilibrium patterns are defined by Lane principle, observed in natural beds, while this balance is disturbed in regulated ones which has been confirmed by research. Natural and regulated rivers stability was evaluated by beds hydrodynamic stability criteria. It showed that the investigated natural rivers bed is stable enough. Under accumulated silt particle sizes in natural river beds, the formation regularities of meanders were determined. The investigated river meanders patterns confirmed the formation of natural river meanders characterizing patterns. It was found that regulated Lithuanian streams through self-beds meandering are useful not only for the natural diversity formation, but also increase meandering bed sediments conveyance capacity and stability from 3 to 3.5 times. Adapting to these naturally occurring processes and using the extensive channel maintenance techniques, it is possible to force the disruption of regulated streams hydrodynamic equilibrium self-recovery and biodiversity. The aim of research - according to the selected river bed hydrodynamic stability criteria to perform comparative analysis of stability of regulated and natural streams.