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Evaluation criteria of protected landscape aesthetic quality
2007
Zigmunde, D., Latvia Univ. of Agriculture, Jelgava (Latvia)
The study focuses on protected landscape aesthetic quality assessment where the main problem is how to associate aesthetical and ecological approaches. High ecological quality does not often correlate with high landscape aesthetic quality, and this relationship may differ depending on specific ecosystem. The landscape aesthetic quality assessment historically developed on two approaches. One of them - expert approach, which has dominated in landscape planning and management practice, and the second - perception approach, which has dominated in research. In protected landscape aesthetic quality assessment traditional approaches will be revised by ecology and green philosophy aspects. The study example regards important natural and protected areas around river Lielupe - from Jelgava city to Kalnciems. This is the landscape with high heritage, natural, biological values and it is also living, recreation place for people. Therefore, cooperation between aesthetic and ecological approaches in landscape assessment is needed. The outdoor investigations were carried out in autumn 2006. There were photographs and video materials on the first stage of investigation. In the second part aesthetic quality of views was analyzed with expert approach. There were three main groups of evaluation criteria of protected landscape aesthetic quality. These covered design and compositional outlines - features, their quality and relationship among these features. The results showed that not all criteria are suitable and effective for evaluation of protected landscape aesthetic quality because of restriction of specific ecological conditions.
Afficher plus [+] Moins [-]Improvement of the parameters of the constructed wetlands filter when applying it for the treatment of dairy wastewater
2007
Askinis, S., Lithuanian Univ. of Agriculture, Kaunas (Lithuania). Water Management Inst.
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).
Afficher plus [+] Moins [-]Distribution of woody vegetation on the slopes of regulated streams
2007
Survilaite, O., Vilnius Gediminas Technical Univ. (Lithuania) | Saulys, V., Vilnius Gediminas Technical Univ. (Lithuania)
The paper presents the study material and analysis of the distribution of woody vegetation of regulated streams in southeast Lithuania. The studies were carried out in 110 randomly selected slope strips of regulated streams in the Neris River basin in the Baltic Highland within the period of 2005 to 2006. During the studies 32 species of woody vegetation were found, from which 14 species of trees and 18 species of bushes. In regulated streams different species of willows are most common. However their distribution on channel slopes is different. For most species of woody vegetation the conditions are most favourable in the lower and middle part of slopes. Here their density is highest (0.34 +- 0.89 and 0.73 +- 0.139 units mE-2 respectively), the frequency is 0.56 and 0.64 respectively. As it was determined, the frequency of woody vegetation on slope strips of regulated streams is na = 0:61. On the slope the lower overgrowth limit of woody vegetation is ra = 1:58 +- 0:16 m, the upper limit is rv = 4:13 +- 0:22 m. In southeast Lithuania, in discharge network of drainage systems there are more possibilities for planning of ecological means, when trees and bushes are allowed to grow on slopes.
Afficher plus [+] Moins [-]Treatment of domestic wastewater by natural means
2007
Askinis, S., Lithuanian Univ. of Agriculture, Kaunas (Lithuania). Water Management Inst.
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.
Afficher plus [+] Moins [-]Relation between spread of cultural heritage and indicators of regional development: case of Latgale region (Latvia)
2007
Paiders, J., University of Latvia, Riga (Latvia) | Sture, I., University of Latvia, Riga (Latvia)
The paper deals with statistic analysis of the relation between variables of cultural heritage and that of regional development in Latgale region. Latgale was selected as the study area - it is one of the five cultural or historical ethnographic regions of Latvia with stable original features, which are formed in the result of the specific historical processes but stands out among other regions of Latvia with the lowest indicators of development. According to the results of analysis of correlation, the number of architectural and archaeological monuments per 1000 people or their density in area have no close correlation with the major part of the parameters under examination. The analysis of regression was carried out between 'the number of architectural monuments against the area', and 'the natural logarithm from the density of population in 2005'. The ratio is expressed by the function y = 0.0339x**2 - 0.1422x + 0.1671, where y is the number of architectural monuments per square kilometre, but x - natural logarithm from the density of population (the number of people per square kilometre). The coefficient of determination for this relation is almost the same as for a functional one - 0.9499. Both for the coefficients of the equation and free member of equation have very high validity (t - empirical respectively 21.7; -11.1; 7.9).
Afficher plus [+] Moins [-]Subjects of entrepreneurship as components of logistics systems in strategic intraregions of Latvia
2007
Radzele, A., Latvia Univ. of Agriculture, Jelgava (Latvia) | Jurgena, I., Latvia Univ. of Agriculture, Jelgava (Latvia)
After the regaining of independence in Republic of Latvia, a new period in the structural-politics of national economy, in choice of enterprise forms and business companies, in their foundation and development began. Beginning from the regain of independence, there has been no published research on these issues for about 16 year period. All studies on this topic were dedicated to separate periods, processes or regions. In the Paper format results of original research have been expounded on the development of entrepreneurship content forms in four separate urban, strategic territories: Daugavpils or Southern-Latgale, Rezekne or Eastern-Latgale, Liepaja - Ventspils or Western-Kurzeme and Riga intra-regions. In the research the whole period since regaining of Latvia independence has been analyzed, as well as the adaption of the law package on entrepreneurship and the beginning of the real entrepreneurship activity in years 1991-1992. Substantial differences between the territories (agglomerations) and also conformities of common development have been defined. There are essential differences in the activity efficiency of entrepreneurship subjects and in the results of the work contributed. The urban influence of big cities increases. The subjects and components of logistics systems develop faster.
Afficher plus [+] Moins [-]Choice of species and varieties of wheat for organic farming
2007
Konvalina, P., University of South Bohemia, Ceske Budejovice (Czech Republic) | Moudry, J., University of South Bohemia, Ceske Budejovice (Czech Republic)
Cereals, the yield of which is strongly influenced by a well-selected variety, belong to the most important crops of organic farming, grown on arable land. At first a questionnaire study was executed among organic farmers in 2006 to gain information concerning the choice of variety, structure of growing, and yield of cereals in the Czech Republic. The actual cultivars of wheat are bred to be suitable for intensive farming. Therefore, not all the actual cultivars are suitable for organic farming. The methodology of tests of the suitability of cultivars for organic farming was elaborated and tested in 2006. Particular morphological, biological and agricultural features were evaluated. Selected Austrian cultivars, which were recommended for in organic farming system and breeded strains were tested. It is difficult to achieve sufficient protein content in grain in the organic farming system. The fact that the protein content in landraces of wheat is higher than the protein content in modern breeded varieties was confirmed. These varieties adapted to local conditions very well. Most of the evaluated varieties contain more crude protein in grain than modern varieties and may achieve a very good-quality production, but on a lower yield level the same as varieties of emmer.
Afficher plus [+] Moins [-]The earliness and sugar content of Latgale's melons
2007
Balins, A., Latvia Univ. of Agriculture, Jelgava (Latvia) | Alsina, I., Latvia Univ. of Agriculture, Jelgava (Latvia) | Lepse, L., Pure Horticultural Research Station, Tukuma reg. (Latvia)
The research was done in 2006 with the aim to observe the earliness and sugar content of melons (Cucumis melo L.) in Tukums region of Latvia. Five lines of Latgale's melons ('8', '14', 'S4(3)', '5(2)', and '4(3)') and five varieties ('Noirdes Carmes', 'Ogen', 'Vedrantais', 'Cantaloup de Bellegarde', and 'Jaune Canaris') from South Europe were grown in high plastic tunnels: five plants from each line and variety. The most appropriate melon line for growing in Latvia conditions was selected according to earliness and sugar content. The study showed that Latgale's melons (Latvian origin) are most suitable for growing in high plastic tunnels under Latvia's conditions. Also some of South Europe melon varieties proved to be suitable for growing in Latvia conditions. All Latgale's melon lines were earlier than South Europe varieties. The highest sugar content was observed in Latgale's melon line '8' (113 g kg¡1) and in South Europe varieties 'Jaune Canaris' (110 g kgE-1) and 'Cantaloup de Bellegarde' (96 g kgE-1). The research demonstrated that in Latvia successful cultivation of melons is possible by using high plastic tunnels.
Afficher plus [+] Moins [-]Incidence of Yersinia enterocolitica 4/O:3 in pigs of Latvian origin at slaughtering
2007
Terentjeva, M., Latvia Univ. of Agriculture, Jelgava (Latvia) | Berzins, A., Latvia Univ. of Agriculture, Jelgava (Latvia) | Liepins, E., Latvia Univ. of Agriculture, Jelgava (Latvia)
A total amount of 90 pig tonsil samples were investigated to detect presence of Y.enterocolitica 4/O:3. Samples were collected in two large-scale Latvian slaughterhouses from five pig herds during February and March, 2006. Samples were investigated with direct plating onto selective CIN agar plates according to ISO 10273 method, with subsequent cold enrichment for 2 weeks at 4 deg C in accordance with NMKL 117 method. Y.enterocolitica positive isolates were investigated for pyrazinamidase and lipase activity, indole production and salicine, xylose, trehalose fermentation. Slide agglutination reaction with commercial antisera O:3 was carried out for detection of Y.enterocolitica sevovars. Pathogen was isolated from all five herds with 30% mean prevalence. Incidence of Y.enterocolitica 4/O:3 depending on herd varied from 20 to 45%. High incidence of Y.enterocolitica in pig tonsils indicates that animals are important reservoir of this pathogen in Latvia. Further studies about incidence of Y.enterocolitica pathogenic bioserotypes in pig population and contamination pattern with pathogen in slaughterhouses are needed.
Afficher plus [+] Moins [-]Minerals in oats, barley and wheat grains
2007
Rubene, D., Latvia Univ. of Agriculture, Jelgava (Latvia) | Kuka, P., Latvia Univ. of Agriculture, Jelgava (Latvia)
The mean content of minerals in grains varies significantly among different parts of the world as it depends on the type of grain growing conditions and fertilizer application. In this study, the content of minerals in the wheat, oat and barley grains of the crop of the year 2006 from different regions of Latvia were investigated. The grain samples were analysed for K, Mg, Ca, Na, Cu, Mn, Fe, and Zn using Atomic Absorbtion Spectrometer, and for P using spectrophotometer. Phosphorus content in different types of grains varied from 3.10 to 5.65 g kgE-1, potassium - from 4.37 to 6.10 g kgE-1, calcium - from 0.40 to 1.40 g kgE-1, magnesium - from 1.20 to 1.68 g kgE-1, manganese – from 14.50 to 55.54 g kgE-1, copper - from 3.35 to 6.01 g kgE-1, zinc - from 18.72 to 31.84 g kgE-1, iron - from 42.39 to 120.40 g kgE-1, and sodium - from 32.34 to 55.52 g kgE-1. The greatest difference was found between the content of manganese and iron in barley, wheat and oat grains, but small difference was between the mean content of P, K, Zn, Cu, Mg, and Na.
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