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Principles for planning residential area greenery Texto completo
2011
Ile, U., Latvia Univ. of Agriculture, Jelgava (Latvia)
The article presents information on the greenery in the large-scale residential area courtyards built in the Soviet period. The data on the importance of the greenery in the large-scale residential areas of the Baltic States were analysed. The analysis was carried out on the large-scale residential area courtyards built in the second half of the 20th century in Pärnu, Jelgava, and Siauliai, which until present have not experienced any changes of the landscape. The research established that these courtyards can be characterised as the unused territory resources. Consequently, there is a necessity to resolve the topical issues of the greenery in the Soviet period large-scale residential area courtyards. From the theoretical aspect, the information gathered in the research on the greenery in the large-scale residential areas has revealed relevant suggestions for the improvement of the present condition. The variety of information reflects the significance of the greenery in the large-scale residential area courtyards that have to provide an aesthetically pleasant image of the territory for every inhabitant of the territory. The methods applied in the research describe the present condition of the Soviet period courtyards.
Mostrar más [+] Menos [-]The historical development of watermills and small-scale hydroelectric power plants landscape in Latvia Texto completo
2011
Lazdane, L., Latvia Univ. of Agriculture, Jelgava (Latvia)
The change in landscape is a never-ending process. In this article information regarding watermills and small-scale hydroelectric power plants historical development in Latvia has been summarized. The research was conducted from September 2010 till April 2011 with the aim of summarizing information regarding impacts to landscape from changes occurring from 12th century till 21st century. The research had a detailed view about the usage history of the watermills, small-scale hydroelectric power plants buildings, and energy producing constructions. The fundamental changes in energy producing mechanisms and legislation regulations changes that have an impact on river open space landscape and on landscape use in surrounded territories of watermills and small-scale hydroelectric power plants landscape were analyzed and studied carefully. The territories were described and analysed using historical, monographic, and comparative methods. The paper gives possible descriptive historical classification of these industrial landscape elements. The historical progress and legislation evolution until the 21st century has also been summarized.
Mostrar más [+] Menos [-]The estimation of the emission of greenhouse gasses by the treatment of sewage sludge in Latvia Texto completo
2011
Arina, D., Latvia Univ. of Agriculture, Jelgava (Latvia);Institute of Physical Energetics, Riga (Latvia) | Bendere, R., Institute of Physical Energetics, Riga (Latvia)
The report presents the assessment of emission of greenhouse gases (GHG) generated by the treatment, disposal and storage of sewage sludge in Latvia. The aim of the study was to determine GHG emissions from stored sludge because those were not previously estimated. The proposals for the further reduction of the GHG emissions are elaborated on the provided estimations of different treatment models. The calculations of GHG emissions are conducted by using acknowledged software and data from Latvian Environment, Geology and Meteorology Centre. Data from the year 2005 till 2009 about the amount of stored sludge were used by the authors for mathematical calculations in the year 2010. The long-term storage of sewage sludge and their disposal in landfills were detected as the main sources of GHG. It was detected that the average GHG reduction of 5 Gg per year can be ensured by using biological treatment of sewage sludge.
Mostrar más [+] Menos [-]Pastoralists’ perception of the impact of East Coast fever on cattle production under extensive management in Northern Rift Valley, Kenya Texto completo
2011
Kipronoh, K.A. | Gathuma, J.M. | Kitala, P.M. | Kiara, Henry K.
A study using participatory epidemiology (PE) methodologies was conducted in West Pokot and Baringo districts, Northern Rift Valley, Kenya to assess the status of East Coast Fever (ECF) and obtain livestock keepers’ perceptions of how the disease impacts on their livelihoods. A total of 658 livestock keepers comprising of 480 men and 178 women were invited to participate in community meetings held in twenty two purposively selected locations each in West Pokot and Baringo. Fifty six percent of the livestock keepers were from West Pokot while the remaining 54 percent were from Baringo District. Nearly all the households in both communities depended on cattle keeping as the major source of livelihood. The activity was ranked as priority enterprise by 96.2% and 93.3% of the groups in West Pokot and Baringo district respectively. Cattle diseases were identified as the main constraint affecting production and in particular, ECF and trypanosomosis were reported as the most important compared to other diseases. The informants were relatively consistent in estimating the impact of cattle diseases on derived benefits. There was good agreement among the various groups with coefficient of concordance (W) values ranging between 0.43 and 0.60 (p < 0:05 – p < 0.01). East Coast fever was found to have the greatest impact. Based on the findings from this study, there is need for stakeholders in the livestock industry to develop control strategies for ECF control that are supportive to the production system in a particular the region.
Mostrar más [+] Menos [-]Winter oilseed rape (Brassica napus L.) autumn growth Texto completo
2011
Balodis, O., Latvia Univ. of Agriculture, Jelgava (Latvia) | Gaile, Z., Latvia Univ. of Agriculture, Jelgava (Latvia)
Lack of data about effect of meteorological conditions, sowing date, sowing rate, fungicide as growth regulator application and other agroecological factors on rape autumn growth is observed in Latvia. The aim of our research, started in autumn 2007 and continued up to autumn 2010 in Research and Study farm ''Vecauce'', was to investigate the influence of agroecological factors (sowing date, sowing rate and fungicide (as growth regulator in autumn)) application as well as meteorological conditions on autumn plant growth of two types of winter rape varieties. Winter rape biometrical parameters were estimated, and meteorological parameters (hydrothermal coefficient (HTC) and growing degree days (GDD)) were calculated. Four year results showed that winter oilseed rape seed germination was affected by precipitation and air temperature around the sowing time. Calculated GDD correlated with plant biometrical parameters during trial years. HTC showed moisture effect on rape emergence time. Sowing date was important factor which had strong and significant impact on biometrical parameters of rape plants in autumn. Earlier sowing date increased height of growth point, root neck diameter, plant and root mass, and main root length significantly for both cultivars in four trial years. Such agro-ecological factor as sowing rate (plant density) affected plant biometrical parameters only in some trial years. Plant weight was significantly influenced by sowing rate for both cultivars if sowing rates were equal. Other important parameter - height of growth point - was not significantly influenced by sowing rate for both cultivars when similar sowing rates were used in all years; exception was year 2009 for 'Californium'.
Mostrar más [+] Menos [-]Influence of woodchip mulch and drip irrigation on fruit quality of sour cherries Texto completo
2011
Feldmane, D., Latvia Univ. of Agriculture, Jelgava (Latvia)
The contents of soluble solids, acids and their ratio as well as phenol content are important indices for quality evaluating of sour cherry fruits. These parameters are influenced by the cultivar and growing conditions. The trial was carried out at the Latvian State Institute of Fruit-Growing to evaluate the effect of woodchip mulch and drip irrigation on fruit quality of sour cherry cultivars 'Bulatnikovskaya', 'Desertnaya Morozovoi', 'Latvijas Zemais', 'Orlica', 'Shokoladnica', 'Tamaris', and 'Zentenes'. The biochemical composition of the fruits was analyzed in 2009 and 2010. The content of soluble solids was determined with the method of refractometry; the content of total acids by titrating with 0.1N NaOH; the total content of phenols with the method of spectrometry. The content of total soluble solids in sour cherry fruits was decreased by use of woodchip mulch. The content of acids, the ratio of soluble solid content to the acid content and the content of the phenols was not significantly influenced by woodchip mulch and drip irrigation. The cultivar 'Desertnaya Morozovoi' showed the highest soluble solid content in the fruits, the cultivar 'Latvijas Zemais' - the highest acid content, and cultivar 'Tamaris' - the highest phenol content in the fruits.
Mostrar más [+] Menos [-]Environmental factors affecting performance traits in Latvian sheep population Texto completo
2011
Puste, A., Latvia Univ. of Agriculture, Jelgava (Latvia) | Kairisa, D., Latvia Univ. of Agriculture, Jelgava (Latvia) | Sarma, R., State Agency Agricultural Data Centre, Riga (Latvia)
This study investigates different environmental effects on birth weight, weaning weight, and pre-weaning daily gain using different statistical models in the Latvian sheep population. The coefficients of determination (R2) were used to estimate the extent of different non-genetic factors influencing birth weight, weaning weight, and pre-weaning daily gain. Data were collected of 4460 lambs born in 36 herds during 2008 to 2010. The birth weight (on average 4.1 ± 0.01 kg), weaning weight (on average 21.0 ± 0.07 kg) and pre-weaning daily gain (on average 242.1 ± 0.93 g) was significantly affected by type of birth and sex, lambing age of dam (covariate) and herd, year, season of birth (p is less than 0.01). Coefficients of determination were estimated from 0.14 to 0.42 for birth weight, from 0.13 to 0.49 for weaning weight, and from 0.10 to 0.46 for pre-weaning daily gain. The results show that when the fixed effects of HYS (interaction between the herd, year, and season of birth) were included it improved the quality of the statistical model most of all, because higher determination coefficients were obtained for all traits: 0.42 for birth weight, 0.49 for weaning weight, and 0.46 for pre-weaning daily gain.
Mostrar más [+] Menos [-]Detection of volatile compounds during wheat dough fermentation Texto completo
2011
Sabovics, M., Latvia Univ. of Agriculture, Jelgava (Latvia) | Straumite, E, Latvia Univ. of Agriculture, Jelgava (Latvia) | Galoburda, R., Latvia Univ. of Agriculture, Jelgava (Latvia)
Taste, smell and the flavour are the most important attributes determining the quality of bread or baked cereal products in general. Bread flavour is composed of hundreds of volatile and non-volatile compounds, i.e. many alcohols, ketones, aldehydes, acids, esters and other compounds. Many researchers have been studying volatile compounds in different breads worldwide, but in Latvia only few studies are conducted on volatile compounds in bread and its production stages. The aim of this research was to analyse the composition of volatile compounds during wheat dough fermentation. Experiments were done in 2011 and carried out in the Laboratory of Bread Technology and Laboratory of Packing Material Investigations at the Department of Food Technology in the Latvia University of Agriculture. An investigation of volatile compounds was done using solid-phase microextraction (SPME) and gas-chromatography mass-spectrometry (GC-MS). Volatile compounds were analyzed on the 10th, 20th and 30th minutes of wheat dough fermentation. In a fermentation process of wheat dough totally 15 volatile compounds were detected. Eight of them were alcohols, two aldehydes, two ketones, one ester, one acid and one terpene. Three volatile compounds – 1-octanol, caryophyllene and acetophenone, were detected in the dough samples only after 30 minutes of fermentation – those were not detected at the earlier stages of fermentation. The peak areas of 11 volatile compounds increased, but peak area of one volatile compound decreased along the fermentation time. The study proved that solid-phase microextraction can be used for detection of volatile compounds in wheat dough fermentation process.
Mostrar más [+] Menos [-]Anthocyanin content in Latvian cranberries dried in convective and microwave vacuum driers Texto completo
2011
Ruse, K., Latvia Univ. of Agriculture, Jelgava (Latvia) | Rakcejeva, T., Latvia Univ. of Agriculture, Jelgava (Latvia) | Galoburda, R., Latvia Univ. of Agriculture, Jelgava (Latvia) | Dukalska, L., Latvia Univ. of Agriculture, Jelgava (Latvia)
The current research focuses on the study of anthocyanin content changes in Latvia wild growing as well as cultivated cranberries during convective and microwave vacuum drying. The research was accomplished on fresh Latvian wild and cultivated cranberries. The berries before drying in a convective drier were pre-treated using perforating, steam-blanching and halving; berries dried in microwave vacuum drier – using steam-blanching and halving; part of berries was dried in microwave vacuum drier without pre-treatment (whole berries). For air drying experiments, a convective dryer “Memmert” (Model 100-800) was used. For drying experiments in microwave vacuum a dryer „Musson-1” was used. Anthocyanin was determined by means of spectrophotometric method. Data are expressed as mean ± standard deviation; variance analysis, homogeneity were used for the evaluation of changes of anthocyanin in cranberries during drying depending on pre-treatment methods. The initial content of anthocyanin among wild and cultivated fresh cranberries was differing: very similar anthocyanin content was detected in cranberry cultivars ‘Pilgrim’ and ‘Early Black’, it was on average three times higher comparing to wild fresh cranberries. However, the lowest anthocyanin content was detected in wild fresh cranberries – 306.81 ± 4.19 mg 100gE-1 (in dry matter). With the probability of 95%, detected by means of the analysis of variance, it may be presumed, that pre-treatment method of cranberries influenced anthocyanin changes during convective and microwave vacuum drying (p=0.001, is less than =0.05). Halving is advisable as a pre-treatment method for berries processing in a convective or microwave drier, because decrease in anthocyanin content is smaller.
Mostrar más [+] Menos [-]Evaluation of quality indices of strawberry mass Texto completo
2011
Boca, S., Latvia Univ. of Agriculture, Jelgava (Latvia) | Skrupskis, I., Latvia Univ. of Agriculture, Jelgava (Latvia) | Straumite, E., Latvia Univ. of Agriculture, Jelgava (Latvia)
Colour, texture and aroma are the main quality attributes of food influencing consumer acceptability of food products. Colour of the product is one of the factors affecting hedonic evaluation. Strawberry mass for a consumer is characteristic by its distinct red colour. The stability of anthocyanins becomes most significant in the case of colour quality. To investigate colour quality, it is necessary to measure colour, as well as pigment concentration. Fresh and thermally treated strawberry mass was analyzed. Formation and stability of anthocyanins, which is the main colour formation substance of berries, are determined by different factors. Anthocyanin colors can be enhanced and stabilized by the addition of different natural or artificial acidifiers. Data of the research indicate that anthocyanin amount during storage period decreases. After 2 days storage their amount increased, but afterwards decreased, both, in fresh and thermally treated mass. The taste evaluation of strawberry mass was essentially affected by the enhancers added. The aim of research was to analyze the quality parameter – colour of strawberry mass with added acidifier which further could be used in production of different products for the needs of public catering, e.g. in production of desserts. The anthocyanin content in strawberry mass with acidifiers was determined to see the organic acid impact to colour stability. Research shows, that natural enhancers – quince and sea buckthorn juices used in the research, did not substantially affect each other’s pH in the product.
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