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Transaction costs of agri-environmental policy measures: the extreme bounds analysis applied to permanent graslands
2008
Nilsson, F.O.L., Swedish Univ. of Agricultural Sciences, Uppsala (Sweden). Dept. of Economics
It has been shown in previous studies that transaction costs (TC) of agri-environmental policy measures often are very large both in absolute terms and as a share of payments. As agri-environmental policy measures make up an increasingly large share of agricultural policies, not least within the European Union, it is becoming ever more important to improve the knowledge about the factors determining the level of transaction costs. This paper investigates the TC determinants of one Swedish agri-environmental policy measure. More specifically, it aims to investigate if the level of TC is attributable to economic factors, such as pasture density and distances, or if political factors, such as lobby groups and political majorities at the county level, influence the costs. To evaluate if the results are robust with respect to alterations in model specifications, a version of the extreme bounds analysis is applied. Although initial results indicate that political parties influence the level of transaction costs, the extreme bounds analysis reveals that those results are fragile. It shows that five of the economic variables are robust with respect to model specifications, but none of the political variables is.
显示更多 [+] 显示较少 [-]Relationship between corruption level changes and economic growth in the world and Europe
2008
Paiders, J., University of Latvia, Riga (Latvia). Faculty of Geography and Earth Sciences
The present article reviews part of a research paper on regional differences in evaluating economic growth and the various aspects that influence it. In this publication, the relationship between changes in corruption level and economic growth is analyzed, paying close regard to all countries of the world and taking Europe separately as a region with relatively consistent economic and social development levels. The author analyzes the average values and changes in gross domestic product (GDP) per capita based on purchasing-power-parity valuation (in US dollars) for 1998 – 2005 and the corruption perception index (CPI) of 1998 – 2007. When looking at data from all countries of the world and European countries, no interrelation can be observed between changes in CPI and GDP per capita. These values fluctuate independently of each other. The obtained results give rise to doubt whether CPI is a suitable indicator for determining the corruption level. The author concludes that assertions of negative (or positive) influence that corruption is said to have on GDP increase should be taken very critically.
显示更多 [+] 显示较少 [-]A formation and analysis of the scenarios in the vocational education research process
2008
Seja, T., Latvia Univ. of Agriculture, Jelgava (Latvia)
In the vocational education research, different methods including a formation and analysis of the development scenarios can be used. In the research of vocational education method of scenarios analysis is hardly ever used. In the article the chance to use the method of scenarios analysis in the research of vocational education in Latvia is evaluated. There is the AHP (Analytic Hierarchy Process) method for analysis of scenarios of the Latvia vocational education development used in the article. There are given methodological recommendations for the realisation of the formation and analysis of development scenarios.
显示更多 [+] 显示较少 [-]The influence of different inventory techniques on the geometrical accuracy of forest geographic data
2008
Bikuviene, I., Lithuanian Univ. of Agriculture, Akademija, Kauno reg. (Lithuania)
This paper deals with the evaluation of the geometrical accuracy of Lithuanian forests compartments geographical data that has been developed using different forest inventory techniques. Geo-reference background database GDB10LT was used as the standard for comparisons. 2500 control points on clearly identifiable places – crossroads, dikes’ intersections, etc. – were selected randomly. The main finding was that the maximal positional root mean square error of clearly identifiable objects in forestry geographic data was 16.47 m (12.37 m and 10.87 m for X and Y coordinates respectively). However, such rather big errors refer to the techniques of GIS database development using paper topographic maps as a background for forest maps and manual digitizing. Enhancement of techniques for GIS database development was found to lead to significant increase in geometrical accuracy of the information.
显示更多 [+] 显示较少 [-]Productivity of Norway spruce stands in state and private forests of Latvia
2008
Libiete, Z., Latvia Univ. of Agriculture, Jelgava (Latvia)
In Latvia, almost 50% of all forests are privately owned. Due to hard economic situation in the 1990ies, many private forests have suffered from illegal forestry operations and overexploitation. One of economically most important tree species for private forest owners is Norway spruce. In this study the productivity of state-owned and private spruce forests was compared, assuming that the stand productivity of private forests should be lower compared to those owned by the state. Data gathered in the Forest Resource Inventory in 2004, 2005 and 2006 was used for the analysis. Total standing volume of the dominant stand and the current mean annual volume increment (CMAI) of spruce were used as main productivity indicators. The mean values of the main stand characteristics were found to be rather similar in state and private forests. The only significant differences were discovered in the mean diameter and CMAI of spruce in 60-90 years old stands; in both cases the values were higher in private forests. Site type and mixture degree were tested as the possible influencing factors. Although there were differences in the site type distribution between state and private forests, the influence of this factor on the CMAI of spruce proved to be insignificant. It was found out that the CMAI of spruce depended significantly on the mixture degree. The proportion of mixed stands in the state forests was considerably higher than in the private forests; presumably therefore the value of the CMAI in the state forests was significantly lower.
显示更多 [+] 显示较少 [-]Grey alder (Alnus incana (L.) moench) structure
2008
Miezite, O., Latvia Univ. of Agriculture, Jelgava (Latvia) | Dreimanis, A., Latvia Univ. of Agriculture, Jelgava (Latvia)
Grey alder occupies 190.6 thousand ha or 6.8% of forests in Latvia. Stand structure has influence on its productivity and dynamics. Materials for the studies were collected in the period from 2005 to 2007. For the investigation 47, grey alder stands, representing various ages, site index and density conditions from Jelgava, Bauska, Ogre, Aizkraukle, Jēkabpils, Valmiera, Talsi and Krāslava regions were used. The majority of these stands have not been managed previously and have been originated from shoots. A total of 11 – 30 - year - old grey alder stands were investigated using a 6 - tree sample plot method. Trees were grouped in 2 cm diameter classes according to breast height diameter. Trees according to reduction numbers were grouped in natural diameter classes. In 11 – 15 - year - old stands trees were within 4 - 5 two centimetre diameter classes, in 16 - 30 – year - old stands – within 6 - 12 classes. The proportions of trees in smallest and largest diameter classes not exceed 1 - 3%. The distribution of grey alder trees in natural diameter classes in 2/3 of cases match up with theoretical Tjurin distribution, resemblance was not detected in cases, when there are large proportions of thin trees in stand. Cumulative percent values of the number of trees and stand volume are were not dependent on site index. Relationship between cumulated value of the number of trees (y) in percents and cumulated value of stand volume (x) was described by parabolic equation (R2 = 0.997, p is less than 0.05). Fifty percent from stand volume were made up from 70% of thinnest trees. Regression equations describing dependence of tree height, height of live crown base, and length of crown from tree diameter were developed.
显示更多 [+] 显示较少 [-]Structure and ecology of ash forest communities pruno-fraxinetum in Latvia
2008
Reihmane, D., University of Latvia, Riga (Latvia). Faculty of Geography and Earth Sciences
The vegetation of Pruno-Fraxinetum plant communities was described in 2004 – 2005 according to the Braun-Blanquet method throughout Latvia, in forests where common ash (Fraxinus excelsior L.) are dominant species in tree layer on moist soils. Classification of relevés (in total 52) by two way indicator species analysis (TWINSPAN) resulted in two variants of this association: typical variant (typicum) and variant with Filipendula ulmaria. Ellenberg indicator values were used to find out the relationship of flora with climatic (light, temperature, continentality) and edaphic (soil reaction, nitrogen, moisture) factors. Canonical correspondent analysis (CCA) was used to find out differences between two variants of Pruno-Fraxinetum. Results of this research have shown that these forests have complicated structure (form four vegetation layers, high species richness), which mainly depends on moist, rich eutrophic soils, usually with presence of limes. Main differential soil factors in ecological analysis are gradients of soil richness: moisture and nitrogen regimes. The influence of other factors was less expressed. Due to the human influence, especially drainage, the moist ash forests are decreasing and the species composition is changed. As Pruno-Fraxinetum forests in Latvia lie on the northern border of its distribution, the species composition differs from forests in the rest Europe; species characteristic determined by floodplain forests in Central Europe are absent.
显示更多 [+] 显示较少 [-]Visible and infrared absorption spectra of covering materials for solar collectors
2008
Pelece, I., Latvia Univ. of Agriculture, Jelgava (Latvia)
Use of solar energy increases every year. In Latvia, solar energy is used mainly by solar collectors. The main part of the solar collector is the absorber, but not less important is the covering material which protects the absorber from the cooling impact of the wind. This cover must be transparent for solar radiation, but opaque for thermal radiation of the absorber, which is at greater wavelengths. Therefore it is important to measure absorption spectra of possible covering materials at visible and infrared wavelength ranges. Absorption spectra have been measured for several materials: glass, polythene, Plexiglas, and cells Plexiglas. Absorption spectra for all these materials are measured in three ranges: ultraviolet – visible (UV – VIS): 250 – 1000 nm; near infrared (NIR): 700 – 110 nm; infrared (IR): 1200 – 8000 nm. UV-VIS spectra with the ‘Ocean Optics’ device HR-4000 have been measured, but NIR and IR – with ‘Bruker’ Furje spectrometer EQUINOX 55. Evaluation of absorption spectra showed that the most suitable material (from the considered) for covering of solar collectors is Plexiglas.
显示更多 [+] 显示较少 [-]Using of AnyLogic and ExtendSim in modelling of biofuel logistic systems
2008
Dukulis, I., Latvia Univ. of Agriculture, Jelgava (Latvia)
Rising oil prices, national security concerns, the desire to increase farm incomes, and a host of new and improved technologies are propelling the European Union to set the directive for the year 2010 – each member state should achieve at least 5.75% biofuel usage of all used transport fuel. The report on the progress made in the use of renewable fuels shows that the average Member State of the EU has achieved only 52% of its target, and biofuels’ share in 2010 will not raise much above 4%. The prices of different biofuels are still not able to compete with oil based fuel prices. One of the possible ways how to solve this problem is to optimize biofuel supply chains using different methods of systems engineering. The aims of this investigation were finding out appropriate simulation tools for biofuel supply chain modelling, development of rapeseed oil supply chains for different production types, and modelling the developed supply chains. As the result of software survey, two packages were chosen – AnyLogic and ExtendSim Suite. Modelling studies showed that rapeseed oil supply chain is very sensitive, because changing just single parameters in a short scale, the actual cost price of 1 litre of oil changes considerably. Comparing the fossil diesel fuel prices with rape oil actual cost from modelling studies, the use of oil as a fuel for farm machinery seems to be profitable. Analysis of costs distribution shows that the greatest part is composed by rapeseed growing expenses.
显示更多 [+] 显示较少 [-]Location of helicobacters in the gastric mucosa of domestic dogs (Canis familiaris)
2008
Berzina, D., Latvia Univ. of Agriculture, Jelgava (Latvia) | Birgele, E., Latvia Univ. of Agriculture, Jelgava (Latvia)
This study was done to evaluate the prevalence and colonization density of helicobacters in the gastric mucosa of domestic dogs (Canis familiaris). Mucosal samples were taken from several places of cardiac, fundic and pyloric gland region of the stomach to detect helicobacters with urease test, brush cytology, and light histological examination. Fourteen dogs of fifteen sampled animals showed positive urease test and the presence of tightly spiraled helicobacters. Positive urease test was observed in 80.4% of all examined samples. Helicobacters were detected in 82.7% of all examined samples by brush cytology and 80.8% of all examined samples by histological examination. Compared to gastric regions, in all employed detection methods have been showed significantly higher prevalence of helicobacters in cardiac and fundic gland region than in the less effected pyloric gland region of the stomach. Histological examination showed the location and colonization density of the bacteria at the superficial epithelium, gastric pits, and deep glandular epithelium of the gastric mucosa in different regions of the stomach. Colonization density of bacteria was evaluated in 4 groups: as absent, mild, moderate, and severe colonization density of helicobacters. Occurrence of helicobacters in the cardiac and fundic gland region showed mild and moderate colonization density of helicobacters at the superficial epithelium and at the gastric pits of the gastric mucosa. Colonization density of spiral-shaped bacteria between the deep glandular epithelium was more pronounced in the pyloric gland region than in the cardiac and fundic gland regions of the gastric mucosa in the domestic dogs.
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