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The influence of different humus layers on the drainage runoff during different seasons Full text
2012
Miseckaite, O., Aleksandras Stulginskis Univ., Akademija, Kauno reg. (Lithuania) | Kincius, L., Aleksandras Stulginskis Univ., Akademija, Kauno reg. (Lithuania)
Hydro-physical properties of heavy or presses soil as well as water regime may be improved by various ways, taking into account the texture of soil and climatic conditions. Drainage is the tool for productive farming and economic benefit generation. Hydrological activity of drainage typically depends on project installation quality, anthropogenic and climatic factors. It is important to assess drainage activity under different meteorological conditions. One of methods to improve drainage performance is its installation with thickened humus layer. Lithuanian soil humus layer is close to arable layer and is equal to approximately 20–25 cm. The impact of humus on heavy-textured soil is multiple, since not only moisture regimes, biological activity, sorption capacity, chemical and biological characteristics, stability of plant nutrition are related with its quantity. The dynamics of drainage activity in soil with thickened (up to 40–50 cm) humus layer and with humus layer of natural thickness (20–30 cm) during various seasons of period of 1989–2009 is reviewed. Especially important indicator of drainage functioning – water runoff dynamics. The present article analyses the variation of climatic conditions and drainage runoff in the object. It is determined that the lowest quantity of precipitation in the researched territory during the research period is in spring and winter but the highest – in summer and autumn. During the research period the highest drainage runoff in the field I was during winter season (46.3%), in the field II – in winter and spring almost the same (32–33%).
Show more [+] Less [-]Risks in agriculture and their assessment methods Full text
2012
Girdziute, L., Aleksandras Stulginskis Univ., Akademija, Kauno reg. (Lithuania)
Agriculture is a unique sector, because it is associated with negative outcomes stemming from imperfectly predictable biological and climatic variables. These variables include natural adversities (for example, pests and diseases), climatic factors are not within the control of agricultural producers. So in agriculture it is very important to identify and evaluate risk, only then decisions made in farm will bring profit and other positive results. Scientific literature distinguishes a lot of methods for risk evaluation, but it is not clear what methods could be adapted in agriculture sector. This article presents main risk types in agriculture and their features as well as introduces most popular risk evaluation methods and their possible use in assessing risks in agriculture.
Show more [+] Less [-]Economic calculation of short rotation willow plantations in Latvia Full text
2012
Makovskis, K., Latvia Univ. of Agriculture, Jelgava (Latvia);Latvian State Forest Research Inst. Silava, Salaspils (Latvia) | Lazdina, D., Latvian State Forest Research Inst. Silava, Salaspils (Latvia) | Bite, L., Latvia Univ. of Agriculture, Jelgava (Latvia)
Short rotation forests (SRF) can be used for biomass production for energy applications in Latvia. Establishment of plantations could be one of possibilities how to reach targets of renewable energy resource (RES) consumption of 40% in 2020. In Latvia’s conditions, one of most suitable species that could be used for SRF is willow (Salix sp.). Abandoned agricultural lands are suitable for establishment of plantations. Productivity of 8 oven- dried tons (ODT) ha-1 year -1 can lead to Rate of Return (IRR) of 17.1% and Net Present Value (NPV) 1099 Latvian Lats (LVL) if the biomass price is 33 LVL ODT-1. Establishment, harvesting and transporting costs account for 88% of the total cost of production. Price of wood chip and fuel plays the most important role in economics of plantation.
Show more [+] Less [-]Policies related to volunteer work in Latvia Full text
2012
Jaunmuktane, A., Latvia Univ. of Agriculture, Jelgava (Latvia)
Volunteer work has been identified as a relatively new kind of leisure activities. It plays an important role in various, at the same time it is a great possibility to learn, acquire new skills and accumulate human capital while taking part in volunteer activities. Therefore, the objective of the study is to research the policies related to voluntary work and their relevance in realization and development of volunteer work in Latvia. Theoretical literature shows that in Latvia the volunteer work is mentioned in some policies – economic, youth policies and civil society. In the framework of economic policy successful development of volunteering enhances the progress of economic processes in the state in two ways by making contributions to Gross Domestic Product; by accumulating person’s human capital, results illustrate that although the term “voluntary work” has a long history, infrastructure for realization of the voluntary work has not been developed in Latvia, and regulatory enactments do not cover voluntary work in an adequate manner. After the analysis the author believes that volunteering is widely discussed in the youth policy as there is law and a range of structured documents where aspects of volunteer work are mentioned. According to the results of research, in the frame of civil society it must be noted that in Latvia the voluntary work movement has to be examined in the context of the establishment of non-governmental organizations because voluntary work movement started to develop in a purposeful and organized manner only in 1998 in non-governmental organizations.
Show more [+] Less [-]An evaluation of using fuel wood for district heating production in Latvia Full text
2012
Bronka, A., Latvia Univ. of Agriculture, Jelgava (Latvia) | Zvirbule-Berzina, A., Latvia Univ. of Agriculture, Jelgava (Latvia)
One can reasonably argue that issues related to the increased use of renewable energy resources in the energy production processes in Latvia, are at the forefront and will remain there in the future. This relates to the aspect that Latvia is not rich in non-renewable energy resources (around 70% of total primary energy consumption in Latvia is ensured by import, which can lead to undesired effects in many areas), but at the same time, there are available renewable energy resources in Latvia, with an untapped potential to be recognized. In particular this applies to fuel wood, which is already (year 2012) the most important domestic fuel in Latvia. In this context it is important to emphasize that, according to the particular study results, if unexpected socio-economic developments do not take place, raw wood material resources required for different types of fuel wood production in Latvia should be available in the same amount as it is now if not more. As for increasing the amount of fuel wood use in Latvia, an enormous ‘potential’ can be seen in general use boiler houses, where there are currently no technological limitations to utilize this ‘potential’. General use cogeneration plants can be recognized as an even greater ‘potential’ for greater use of fuel wood in Latvia, but given the circumstances of energy supply in Latvia, the ‘potential’ is currently available on a very limited basis. At the same time it is important to note that both of these ‘potentials’ could be significantly reduced in the next few years.
Show more [+] Less [-]Estimation of potential impact of coastal erosion protection in Latvia Full text
2012
Brunina, L., Latvia Univ. of Agriculture, Jelgava (Latvia) | Konstantinova, E., Information Systems Management Inst., Riga (Latvia)
The Baltic Sea problems in context of erosion always have been very topical and since ancient times have been caused by uncontrollable and unpredictable natural factors (storms). These factors combine with the impact of human economic activities of the direct effect of factors -building offshore and aquatorium, deficit of sediment and marine dredging and growth of recreational tourism growth that promote load of coastal vegetation and dune relief. The identification of costs and benefits is significant step for evaluation of the impact of the Project and usefulness of the costs. The positive impact or benefits can occur at once, after a while or long term perspective. The economic evaluation techniques particularly cost-benefit and cost-effectiveness analysis for coastal protection in this case used for ascertain the most effective alternative. The sensitivity analysis was made for verifying impact of alternatives on taken solution. The aim of research is to verify the economic methods for application to coastal management in Latvia. The world’s coastal scientists believe that the future of coastal policy will become increasingly polarized and discussed; therefore, gradual implementation of the assessment process and development of socio-economic indicators is recommended.
Show more [+] Less [-]Winter oilseed rape (Brassica napus L.) autumn growth Full text
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'.
Show more [+] Less [-]Influence of woodchip mulch and drip irrigation on fruit quality of sour cherries Full text
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.
Show more [+] Less [-]Environmental factors affecting performance traits in Latvian sheep population Full text
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.
Show more [+] Less [-]Detection of volatile compounds during wheat dough fermentation Full text
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.
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