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Comparison of productivity of CBI and MCR-500 stump lifting buckets in Latvia Full text
2013
Zimelis, A., Latvia Univ. of Agriculture, Jelgava (Latvia);Latvian State Forest Research Inst. Silava, Salaspils (Latvia) | Lazdins, A., Latvian State Forest Research Inst. Silava, Salaspils (Latvia) | Sarmulis, Z., Latvia Univ. of Agriculture, Jelgava (Latvia)
The stump lifting trials were implemented in 5 forest compartments of the JSC ‘’Latvia state forest’’ Vidusdaugava, Rietumvidzeme, Zemgale and Ziemeļkurzeme forestries in autumn, 2012. Total extracted area was 3.5 ha, excluding control. Two stump extraction buckets were compared in these trials – CBI (made in Canada) and MCR-500 (made in Latvia). The scope of the study was to estimate if the prototype of the MCR-500 can compete with stump lifting buckets having positive feedback from industry. Considering that the CBI head cannot prepare soil, this operation was not done by the MCR-500 either. In total 1796 stumps were marked and their main parameters were taken in all trial areas. Extracted biomass was estimated theoretically using biomass expansion factors elaborated in Nordic countries. Allegro CX field computers with SDI software were used in time studies to obtain information about productivity and distribution of productive time in a work cycle. The study demonstrated that productivity of stump extraction with both stump lifting buckets did not differ significantly in 6 cases out of total 10 comparisons.
Show more [+] Less [-]Economic value of wood chips prepared from young stand tending Full text
2013
Kaleja, S., Latvia Univ. of Agriculture, Jelgava (Latvia) | Grinfelds, A., Latvia Univ. of Agriculture, Jelgava (Latvia) | Lazdins, A., Latvian State Forest Research Inst. Silava, Salaspils (Latvia)
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.
Show more [+] Less [-]Internal factors affecting competitiveness of Latvian small and medium-sized furniture manufacturers Full text
2013
Lise, S., Latvia Univ. of Agriculture, Jelgava (Latvia) | Marcins, J., Latvian Association of Wood Processing Entrepreneurs and Exporters, Riga (Latvia)
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.
Show more [+] Less [-]Determining the surface energy components of wood using the contact angle method Full text
2013
Laiveniece, L., Latvia Univ. of Agriculture, Jelgava (Latvia) | Morozovs, A., Latvia Univ. of Agriculture, Jelgava (Latvia)
The properties of the transverse section surface of the wood are crucial when using it as an adhesive in finger joints. Contact angles of three test liquids sessile drops - water, diiodomethane and ethylene glycol - with known characteristics of surface free energy were measured on wood surface with the grain orientation 45 ° against the plane. Acid–base approach was used to calculate surface free energy and its characteristics of Scots pine (Pinus sylvestris L.) with moisture content of 21% and Norway spruce (Picea abies L. Karst) with moisture content of 10% wood samples from values of the contact angle. The wetting behavior of the wood samples was examined with the contact angle method (goniometer technique) in the Laboratory of the Department of Chemistry of Latvia University of Agriculture at the beginning of 2013. The aim of this study was to verify possibility of determining the contact angle values of the wood and calculate the surface free energy and its components of wood from the obtained contact angle values using acid-base theory. At the end of this study it was concluded that the acid–base approach is a suitable method to calculate surface free energy and its characteristics of wood from the values of the contact angle. Nevertheless, indirect methods of liquid drop contact angle value estimation must be used because direct determination is not feasible on wood surfaces with open capillaries.
Show more [+] Less [-]The Latvian landscape as seen from the road Full text
2013
Vugule, K., Latvia Univ. of Agriculture, Jelgava (Latvia)
Roads play an important role in our daily surroundings and provide access to landscape. Views from the road create the first impression about the country. It is important to pay attention to the landscapes along the roads used by tourists. The purpose of this study was to obtain general overview of the current state, identify existing and disappearing features of the road landscape in Latvia. Research on road landscape perception and design is well developed in the USA and some countries in Europe. The assessment of the current state and proposals for the road landscape development in Latvia are fields which are little discussed and need more attention. The research was carried out in several sections of the main roads and some sections of regional and local roads in July and August, 2011 and August, 2012. Photography method was used. Analysis of the results shows that the main reasons of aesthetic quality loss in road landscapes is lack of planning and management, indicating the necessity to find ways for rural landscape quality enhancement.
Show more [+] Less [-]The impact of interpolation method parameters on the accuracy of predicted values Full text
2013
Vyciene, G., Aleksandras Stulginskis Univ., Akademija, Kauno reg. (Lithuania) | Grybauskiene, V., Aleksandras Stulginskis Univ., Akademija, Kauno reg. (Lithuania)
Kriging is a method of interpolation, which predicts unknown values from data observed at known locations. This method uses a variogram to express spatial variation, and it minimizes the error of predicted values which are estimated by spatial distribution. The objective of the current work was to investigate how the accuracy of predicted runoff average depth values ranges by applying ordinary Kriging interpolation method when parameters of the method are altered. The simulation was tested by the following method parameters on: fitted semivariogram model, lag size, neighbouring points; the number of sectors of the circle. The best results of the spatial distribution of runoff average depth were received applying the ordinary Kriging method when the exponential variogram is used, the lag size being 27 km while 6 contiguous points and the orbicular scheme divided into sectors in 45° angle are taken. Applying the Ordinary Kriging method having selected all parameters with probability p = 0.95 the model described about 74% of all investigated values.
Show more [+] Less [-]Grishanin factor as criterion for river stability estimation Full text
2013
Vaikasas, S., Aleksandras Stulginskis Univ., Akademija, Kauno reg. (Lithuania) | Baublys, R., Aleksandras Stulginskis Univ., Akademija, Kauno reg. (Lithuania)
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.
Show more [+] Less [-]The cycles of phosphorus in crop rotations differing in fertilization Full text
2013
Guzys, S., Aleksandras Stulginskis Univ., Akademija, Kauno reg. (Lithuania)
The investigations were carried out during the period 2006-2011 in the land of the Water resources management institute of ASU, in the village of Lipliūnai on Endocalcari Endohypogleyic Cambisol (CMg-n-w-can). The base of investigations is 3 drainage systems, which contain cereals differing in fertilization and grass crop rotations. The aim of investigations is to determine the crop rotations differing in fertilization and these relations with cycles of phosphorus in agroecosystem. Higher productive was perennial grass crop rotation. In the conditions of cereal crop rotations this productive was 3-46% lesser. The highest concentration of P-PO4 3- in drainage water was received in the conditions of higher fertilization cereals crop rotation while highest concentration of total P was in the conditions of grass crop rotation. The concentration of P-PO4 3- in drainage water essentially depends on amount of mobile P2 O5 in soil, fertilization, productivity of field crops, drainage runoff as well as cumulative balance of P. The highest leaching of P-PO4 3- and total P by drainage was received under the conditions of higher fertilization cereals crop rotation. The leaching of P-PO4 3- essentially depends on fertilization, drainage runoff as well as cumulative and yearly balance of P. The application of all crop rotations was distinguished by positive P balance.
Show more [+] Less [-]The impact of land drainage on Nevezis River flow Full text
2013
Taparauskiene, L., Aleksandras Stulginskis Univ., Akademija, Kauno reg. (Lithuania) | Maziliauskas, A., Aleksandras Stulginskis Univ., Akademija, Kauno reg. (Lithuania) | Miseckaite, O., Aleksandras Stulginskis Univ., Akademija, Kauno reg. (Lithuania)
Most of the regulated rivers are situated in the middle part of Lithuania. Approximately 90% of all agricultural lands are drained in the Basin of Nevezis River, which is one of the most sensitive basins in Lithuania due to the lack of water and potential anthropogenic pollution. The goal of the research is to assess the impact of drainage on Nevezis River flow. Following the data series of 62 years, it was determined that water balance of Nevezis Basin is characterized by negative water balance during May-September due to higher evapotranspiration than average precipitation amount of the same period. It was stated that the average annual flow coefficient of the whole 10th hydrologic region of Lithuania was 0.3 till reclamation. It decreased to 0.28 during the period of intensive reclamation; however, the average annual flow was 0.35 from the year 1980, i.e., it increased in comparison with the period till reclamation. The average flow coefficient of warm period was 0.10 till reclamation, and remained the same during the period of 1956-1980, while the data of 1981-1995 show that the average flow coefficient increased – 0.11. After assessing the meteorological conditions and soil water balance of the Basin of Nevezis River it might be stated that the primary reason of water lack in the basin is climatic conditions. Drainage systems can hardly have a significant impact on wateriness of Nevezis River.
Show more [+] Less [-]Regional inequalities of the agricultural economy in Latvia (1935–1939) Full text
2013
Paiders, J., University of Latvia, Riga (Latvia) | Paiders, Ju., University of Latvia, Riga (Latvia)
The aim of this research is to evaluate the spatial differences of the agricultural economy of Latvia during the First Republic by using spatial autocorrelation calculations. Morans’s I coefficient of spatial autocorrelation is used to describe the spatial relations of the analyzed indicators. The obtained results show that Moran’s I for more than half of the obtained parameters is greater than 0.5, which indicates a rather high spatial autocorrelation. It was observed that variations of the spatial autocorrelation values can be explained by what affects these parameters. Spatial autocorrelation is significantly higher for those parameters whose value depends mainly on the variety of natural factors (land use, specific crop share). Moran’s I value for those parameters whose values depend on the actions by the local government in rural parishes is considerably lower (for example, budget allocation, etc.) A large portion of the examined parameters characterizing the level of parish economic development show the biggest differences when comparing Latgale with the rest of Latvia. In the case of such regional differences, Moran’s I is usually within 0.5–0.7, indicating moderately close spatial autocorrelation. For many indicators regarding agriculture and land use many southern parishes within Jelgavas and Bauskas county show a very considerable difference from the rest of Latvia showing much higher rate of agricultural production.
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