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Scenic roads in Latvia 全文
2016
Vugule, K., Latvia Univ. of Agriculture, Jelgava (Latvia) | Turlaja, R., Latvia Univ. of Agriculture, Jelgava (Latvia)
United States of America and European countries like Great Britain, Germany, Norway have long traditions in the development of scenic roads, special scenic routes for tourists, National Scenic Byway Programs. They have set criteria for road landscape planning and design, discussed the economic value of scenic roads. Scenic roads are also important for tourism, as well as visual and cultural countryside development in Latvia. Planning regions and regional communities in Latvia have strategic development plans and spatial plans. All of them include high value landscapes and protected, scenic territories. Some scenic roads are defined in these documents, but criteria for scenic road designation are set in every region individually. There are unlisted roads with high aesthetic value which could be protected. Common methods, criteria for the assessment of road landscapes and scenic road designation in Latvia are not developed. The aim of the research was to evaluate and understand the present situation of scenic roads in Latvia. An online questionnaire was carried out in order to find out peoples’ opinion about the road landscape quality. Spatial plans of regional communities and planning regions were examined. A field study of two sections of scenic roads was carried out. The research project was carried out from December 2014 to December 2015. Results show that current road landscape has a potential for development, and it needs improvements. The study gives a general insight into the scenic road situation in Latvia and provides basis for further research on scenic road planning and management.
显示更多 [+] 显示较少 [-]The compositional solutions of the historical parks in Latvia 全文
2016
Ziemelniece, A., Latvia Univ. of Agriculture, Jelgava (Latvia)
The information about gardens of the Duchy of Courland in the 17th century is scarce and fragmentary, as part of documents is lost or exported abroad during the war. The time of the Duchy and its baroque gardens is attributed to reign of E. J. Biron in the first half of the 18th century, when impressive palace ensembles were created the help of architects F. B. Rastrelli and S. Jensen, building of summer residences in Rundāle, Vircava, Svēte, Luste. They served as summer amusement gardens or parks. In their arrangement, a compositional connection with the palace, the front courtyard, outbuildings and the garden was sought. These summer residences were located in rural plain areas, thus, the features of natural area - water, floodplains, terrain, nature of plantations and materials were used. The choice of planting materials was influenced by the climatic conditions - harsh winters, short summers, late spring frosts or early autumn frosts. Therefore, in the Duke’s time gardens, there are no delicate plants such as jews, boxwood plants, peach and mandarin fruit trees imported from the Western Europe. The local trees and shrubs, fruit trees, spice plants were used, vegetable beds made. The study examines two of the Duchy’s summer residences at Vircava (Wūrzau) and Svēte (Swethof), the study of which, as already mentioned, is made difficult due to the relatively scarce information.
显示更多 [+] 显示较少 [-]Surface water - groundwater interaction in the Salaca drainage basin using stable isotope analysis 全文
2016
Babre, A., University of Latvia, Riga (Latvia) | Kalvans, A., University of Latvia, Riga (Latvia) | Popovs, K., University of Latvia, Riga (Latvia) | Delina, A., University of Latvia, Riga (Latvia) | Retike, I., University of Latvia, Riga (Latvia) | Bikse, J., University of Latvia, Riga (Latvia)
This paper presents first results of monthly water stable isotope monitoring programme covering the most important surface and groundwater types in the Salaca River basin. The aim is to characterise the isotopic values of different water types in the Salaca River basin, and test if their contribution can be identified in the Salaca river runoff. A monthly groundwater and surface water stable isotope monitoring programme was initiated in August 2015 covering the most of the important surface and groundwater types in the study region – groundwater and surface water in the raised bogs, free-surface groundwater including artificially drained agricultural lands, water emerging from the Lake Burtnieks as well as Burtnieks and Arulika confined aquifers. Preliminary results show that stable isotopes are useful tool to identify distinct water components and their evolution. However, it is needed to continue monitoring programme to draw significant conclusions.
显示更多 [+] 显示较少 [-]The abandoned block-cut peat extraction field influence on the natural raised bog hydrological regime 全文
2016
Purmalis, O., University of Latvia, Riga (Latvia);Institute for Environmental Solutions, Riga (Latvia) | Grinfelde, I., Latvia Univ. of Agriculture, Jelgava (Latvia) | Valujeva, K., Latvia Univ. of Agriculture, Jelgava (Latvia) | Burlakovs, J., University of Latvia, Riga (Latvia);Linnaeus Univ. (Sweden). Faculty of Health and Life Sciences
Peat is still mined in many parts of the world for production of peat substrates and energy. Many peatlands were affected by drainage in the past also for forestry and agricultural needs. Nowadays a raised attention to peatlands is focused, especially to drained peatlands due to their carbon reserves and their potential influence to the climate on the one hand, but on the other hand - due to raising awareness on protection of environment, habitats and biotopes. There are many examples on restoration activities in peatlands found worldwide, especially their water regime is the subject of regulation, which plays the major role to bring back original functions. In most cases in Latvia as the aim for protection and restoration of degraded peatlands was protection of EU biotopes and habitats. Of course, peatlands play an important role in emissions of the greenhouse gases CO2, CH4 and N2O, produced during mineralization of the drained peat organic matter. In literature, we can find only few cases where hydrological regimes are described for natural raised as well as restored block-cut peat extraction fields. This research analyses block-cut peat extraction field water level fluctuation influence on naturally raised bog hydrological regimes. Hourly data is analysed for six groundwater monitoring wells as well as for determination needs of water level fluctuations in excavated peat quarry as a response to precipitation.
显示更多 [+] 显示较少 [-]The effect of planting density on potato (Solanum tuberosum L.) minituber number, weight and multiplication rate 全文
2015
Dimante, I., State Priekuli Plant Breeding Inst., Priekuli, Priekuli parish, Priekuli Municipality (Latvia) | Gaile, Z., Latvia Univ. of Agriculture, Jelgava (Latvia)
The study was aimed to investigate the effect of potato (Solanum tuberosum L.) in vitro plantlets planting density under greenhouse conditions on obtained minitubers number per unit area, multiplication rate and their weight distribution. Three cultivars of different maturity (‘Monta’ – early maturity, ‘Prelma’ – medium early and ‘Mandaga’ – medium late maturity) were used for the study. In vitro plantlets were planted in a greenhouse of State Priekuli Plant Breeding Institute, Latvia in 2014 at four planting densities (PDs) 63 plants per square m, 95 plants per square m, 142 plants per m2 and 184 plants per square m respectively. Fertilized peat was used as a substratum. Significant effect of planting density (p is less than 0.001) and cultivar (p is less than 0.01) was found on analyzed yield parameters. Increased planting densities resulted in increased minitubers number per square m (from 272 minutubers mE-2 at PD 63 plants mE-2 to 414 minutubers mE-2 at PD 184 plants mE-2), decreased multiplication rate (4.3 to 2.7 minitubers per planted plant) and mean fresh weight of minitubers (from 20.26. g to 12.11 g). The highest increase of minitubers number per m2 was observed within size (weight) range 3 to 5 g. Minitubers number per m2 increase within bigger size ranges (5 to 10 g, 10 to 20 g) was less pronounced. Slight insignificant (p=0.330) decrease of minitubers number is greater than 20 g was observed in relation of planting density increase (112 minitubers mE-2 at PD 95 plants mE-2 to 84 minitubers mE-2 at PD 184 plants mE-2).
显示更多 [+] 显示较少 [-]Effect of post-harvest mowing on strawberry 'Darselect' growth and yield grown on plastic mulch 全文
2015
Raetsep, R., Estonian Univ. of Life Sciences, Tartu (Estonia) | Karp, K., Estonian Univ. of Life Sciences, Tartu (Estonia) | Vool, E., Estonian Univ. of Life Sciences, Tartu (Estonia)
The experiment was carried out at the Research Centre of Organic Farming of Estonian University of Life Sciences in 2012 and 2013. The study was aimed to find out the effect of defoliation and humic acid application on the strawberry (Fragaria × ananassa Duch.) plant growth, yield, and on the ascorbic acid, total phenolic and anthocyanin contents in ‘Darselect’ yield. Defoliation decreased significantly the number of leaves and inflorescences in both experimental years, while the fertilization effect was only in one experimental year. Fruit weight ranged from 19 to 42 g, being significantly decreased by defoliation in 2012, but increased in 2013. Yield was decreased due to defoliation up to 40% in 2012 and up to 51% in 2013, but humic acid application increased the yield of the defoliated plants in both experimental years. Defoliation in combination with humic acids had a significant effect on strawberry ascorbic acid content, but the effect was different for different fruit order. Tertiary fruits contained up to 46% more of total phenolics due to defoliation in both experimental years. Defoliation increased anthocyanins in primary and secondary fruits, but decreased it in tertiary fruits; while fertilizing increased the content up to 45% in defoliated plants in primary, but decreased about 13% in tertiary strawberries.
显示更多 [+] 显示较少 [-]Industrial potato peels waste application in food production: a review 全文
2015
Sepelev, I., Latvia Univ. of Agriculture, Jelgava (Latvia) | Galoburda, R., Latvia Univ. of Agriculture, Jelgava (Latvia)
Potato (Solanum tuberosum L.) is one of the most important agricultural crops for human consumption and high amount is produced worldwide every year. Potato peel waste is a zero value by-product, which occurs in big amounts after industrial potato processing and can range from 15 to 40% of initial product mass, depending on the peeling method. Food waste utilization causes great concern in food industry in Europe and many scientific works were written on this topic in the last years offering solutions and original approaches. Present article aims to summarize the review of available literature on industrial potato peel waste application possibilities in food production industry. Scientific articles on food waste management, potato peel chemical composition and recycling methods have been studied. The main results show, that there is a big potential for potato peel extract as an antioxidant in food systems due to its high phenol content. In addition, potato peel powder could serve as a partial flour replacement in dough up to 10 g 100 gE-1 of flour weight without causing significant changes in sensory properties. Potato peel waste can serve as a solid substrate for fermentation. Further investigations in the present field are needed in order to evaluate full potato peel waste application potential.
显示更多 [+] 显示较少 [-]Rheological properties of whole grain wheat, rye and hull-less barley flour blends for pasta production 全文
2015
Kalnina, S., Latvia Univ. of Agriculture, Jelgava (Latvia) | Rakcejeva, T., Latvia Univ. of Agriculture, Jelgava (Latvia) | Kunkulberga, D., Latvia Univ. of Agriculture, Jelgava (Latvia)
Whole grain flour can be considered as a good candidate for pasta fortification due to the health benefits. Literature reports pasta dough fortification with non-traditional ingredients and cereals. Therefore, the purpose of the current research was to investigate rheological properties of whole grain flour blends for pasta production. Flour blends were made from wheat flour (type 405) in a combination with other flours (whole grain wheat, rye or hull-less barley flour) in various proportions (from 10% to 50%). Wheat flour type 405 was used as a control. Rheological properties of dough were analysed using Farinograph AT (Brabender, GmbH and Co.KG., Germany) and starch gelatinization properties of flour starch using Amylograph-E (Brabender GmbH and Co.KG., Germany); moisture content of flour samples (AACC 44-15A from 2000). The results of present research demonstrate that rheological properties of dough decrease if the amount of whole grain flour in blend increases. It was concluded that water absorption and dough development time of dough with whole grain flour blends addition is less than the parameters of control wheat flour (type 405). However, a higher starch gelatinization was obtained for flour blends with whole wheat grain flour, comparing to blends with whole rye and hull-less barley grain flour, which mainly could be explained with a higher gluten content of whole wheat grain flour.
显示更多 [+] 显示较少 [-]The potential of fructans producing acetic acid bacteria in fermented dairy products 全文
2015
Feldmane, J., Latvia Univ. of Agriculture, Jelgava (Latvia) | Ciprovica, I., Latvia Univ. of Agriculture, Jelgava (Latvia) | Sabovics, M., Latvia Univ. of Agriculture, Jelgava (Latvia)
In this work the combinations of commercial lactic acid bacteria starters and acetic acid bacteria strain were used for production of fructans in substrate, both with and without sucrose additive, and studied their potential in maintaining technological properties of yoghurt and fermented milk. The objective of this study was to assess the effect of fructans producing starter cultures on milk coagulation technique, the amount of secreted fructans and viscosity of fermented milk samples. An amount of fructans synthesized by starter cultures and Gluconobacter sp. B35, pH and viscosity of samples were measured using appropriate standards and analytical methods. Results showed that the addition of acetic acid bacteria did not influence the pH dynamics of fermented milk samples. Increasing sucrose concentration in samples significantly influences fructans production potential. The application of such technology in fermented dairy product production would have potential from microbiological exopolysaccharides increasing position with the aim to promote functionality of dairy foods and to substitute commercial stabilisers etc. The addition of acetic acid bacteria in milk showed negative impact on viscosity of the evaluated samples. The viscosity was liquid in all analyzed samples with acetic acid bacteria, the addition of sucrose helped to make the consistency of yoghurt and fermented milk more liquid. We concluded that the structure of synthesized fructans could not help to improve the textural properties of fermented dairy products. From this point of view, the studied acetic acid bacteria strain should have the potential as prebiotic.
显示更多 [+] 显示较少 [-]Prevalence of Mycoplasma gallisepticum in the commercial layer flock 全文
2015
Zute, I., Latvia Univ. of Agriculture, Jelgava (Latvia) | Valdovska, A., Latvia Univ. of Agriculture, Jelgava (Latvia)
Avian mycoplasmosis have been considered a severe problem in poultry diseases; Mycoplasma gallisepticum being one of the most important. This study was conducted in Joint-Stock Company Balticovo, Latvia, to determine the prevalence of M. gallisepticum infection in hen’s flocks in the farm. A total of 904 serum and 335 swab samples from non-vaccinated birds against M. gallisepticum from 65 chicken flocks of different age, from day 1 to 75 weeks old, were all tested. The commercially available enzyme-linked immunosorbent assay (ELISA) and polymerase chain reaction (PCR) tests were used. Results revealed that the seropositive flock rate, based on ELISA tests and, according to ratio that represents the extent to which a light source effectively stimulates the rods: S/P ratios and antibodies titer higher 1.076 were 22/904 (2.43%) and 4/904 (0.44%), respectively, while PCR-positive flock rates were not confirmed. Seroprevalence of M. gallisepticum in commercial layer flock in Latvia was more common seen in birds from 17 to 30 weeks of age.
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