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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.
Показать больше [+] Меньше [-]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).
Показать больше [+] Меньше [-]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.
Показать больше [+] Меньше [-]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.
Показать больше [+] Меньше [-]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).
Показать больше [+] Меньше [-]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.
Показать больше [+] Меньше [-]Use of redworms (Perionyx excavatus) to manage agricultural wastes and supply valuable feed for poultry Полный текст
2009
Vu, Dinh Ton | Han Quang, Hanh | Nguyen, Dinh Linh | Nguyen, Van Duy
peer reviewed | Perionyx excavatus, cultured in Vietnam in early 1990s, showed an important role in managing organic wastes and supplying a very nutritious feed for animals. To develop vermiculture in practice, four treatments of different substrates including 100% fresh cattle manure (CM); cattle manure + pig manure in 50:50 ratio (CPM); cattle manure + pig manure + rice straw in 50:40:10 ratio (CPMRS) and pig manure + rice straw in 90:10 ratio (PMRS) were prepared to examine worms’ growth and their decomposition efficiency. All substrates were composted 45 days before feeding to worms. The result showed that cattle manure (CM) was the best substrate for worm growth (biomass gained 713 g after 45 days or 242.6% of growth rate). The worm biomass achieved in CPMRS and PMRS treatments was significantly lower than that in CM treatment. As compared to primary substrates, vermicomposts exhibited an excellent result with a great increase in the amount of total P (0.3 – 0.6%), total K (0.09 – 0.23%), Ca (0.51 – 0.79%) and a decrease in N-NH3 and N-NH4+. A study was carried out to evaluate the influence of feed supplemented with worms on the growth and meat quality of broiler chickens (n=148). Starting at 4 weeks old the chickens were divided into a control group and three experimental groups corresponding to worm levels in the diet of 1, 1.5 and 2% on a dry matter basis according to a completely randomized design. Chicken fed the diet supplemented with 2% worms had the highest live weight at 10 weeks (1925 g/head vs 1823 g/head for the control). Percentage of breast and leg meat was also higher than in the control group. Chickens in the three worm groups had better FCR. The different levels of red worm supplementation did not affect meat quality (pH, color, and the rate of dehydration after storage and processing).
Показать больше [+] Меньше [-]Systems of farming and rural landscape in the Czech Republic
2007
Moudry, J., University of South Bohemia, Ceske Budejovice (Czech Republic) | Konvalina, P., University of South Bohemia, Ceske Budejovice (Czech Republic)
Agriculture of the Czech Republic has features of submonate and montane agriculture. More than half of the surface of the Czech Republic is less favourable areas (LFA). Organic farming is carried out on the area of 6% of the surface of arable land. The contemporary state of farming has been evaluated and organic and conventional farming systems have been compared in the framework of the analysis of structure of farming in the Czech Republic. The selective group of 437 associations, consisting of 3 subgroups, is divided into several categories according to the farming method and altitude. Parameters of plant and animal production and use of the agro-environmental programmes and measures are evaluated. The evaluation of the structure of farming permits to find optimal possibilities for future development of conventional and organic farming in the Czech Republic and for arrangements of the settings of grants and subsidies.
Показать больше [+] Меньше [-]Grain chemical composition of spring barley genotypes
2007
Bleidere, M., Latvia Univ. of Agriculture, Jelgava (Latvia) | Grunte, I., State Agency State Stende Inst. of Cereals Breeding, Dizstende, Talsu reg. (Latvia)
The objective of the study was to examine the range of variation in chemical composition of different barley types. Field experiments were carried out at the State Stende Cereal Breeding Institute from 2004 to 2006. Grain samples of 52spring barley (Hordeum vulgare L.) genotypes, including two-row, six-row, covered and hull-less genotypes were analysed for starch, crude protein, crude fat, crude fibre, crude ash and phosphorus. On the average, the six-row barley genotypes had a significantly larger content of crude protein (152.0 g kgE-1), crude fibre (53.5 g kgE-1), crude ash (24.4 g kgE-1) and phosphorus (4.7 g kgE-1) but less starch (590.4 g kgE-1) than the two-row barley genotypes (626 g kgE-1). The hull-less barley grain contained significantly more crude protein (149.4 g kgE-1), crude fat (25.4 g kgE-1) and phosphorus (4.7 g kgE-1) than covered ones. The largest coefficient of variation was found for crude protein of covered barley (15.0%), for crude fibre of hull-less barley (13.8%) and for phosphorus of six-row barley (18.0%) genotypes. Consequently, energetic value was slightly higher in the hull-less barley with waxy type of endosperm, because of the higher fat (27.1-28.3 g kgE-1) and starch content (622.3-680.7 g kgE-1) and less crude fibre (17.3-17.4 g kgE-1) and crude ash (18.9-21.2 g kgE-1) content.
Показать больше [+] Меньше [-]Effect of selenium on thiamine, riboflavin and pantothenic acid content in different grains
2007
Duma, M., Latvia Univ. of Agriculture, Jelgava (Latvia) | Karklina, D., Latvia Univ. of Agriculture, Jelgava (Latvia)
The effect of selenium on the content of thiamine (vitamin B1), riboflavin (vitamin B2), as well as pantothenic acid (vitamin B5) in wheat (Triticum aestivum L), hull-less barley (Hordeum vulgare L.) and hull-less oats (Avena sativa L.) grains during germination were investigated. The winter wheat grain variety 'Zentos', hull-less barley and hull-less oats were used for study. Grains were soaked for 120 hours totally in solutions containing selenium from 10 to 200 mg lE-1 in the form of sodium selenate (Se+6). Grains with moisture content of 43%-44% were let to sprout at ambient temperature of 18+-2 deg C. The content of B1, B2 and B5 vitamins in germinated grains were determined using standard methods. Laboratory studies showed that changes in vitamin B1, B2 and B5 content depend on selenium concentration and kind of grains. Selenium additives promote biochemical activity of vitamin B1 and content of this vitamin decreases after 5 days' germination in all investigated grains at all applied selenium concentrations. Selenium concentrations of 10 and 25 mg lE-1 promote forming of vitamin B2 in wheat, barley and oat grains. The changes in vitamin B5 content depend on selenium concentration and kind of grains.
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