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Streams water quality analysis in manure fertilized fields
2014
Miseviciene, S., Aleksandras Stulginskis Univ., Akademija, Kauno reg. (Lithuania)
The research was conducted during the period of 2007-2011 in the fields fertilized by manure of pig breeding complex. According to the fertilization value of manure, the following total nitrogen levels reached the fields each year: 2007 – 169, 2008 – 167, 2009 - 168, 2010 - 168, 2011 – 168 kg haE-1. Ptotal reached the fertilized fields accordingly: 2007 – 9.4, 2008 – 18.9, 2009 – 12.0, 2010 – 10.8, 2011 – 13.5 kg haE-1. The aim of the research was to explore the impact of manure fertilized fields of a pig breeding complex on the water quality of streams. Streams, flowing through fields fertilized with manure, are usually polluted with nitrogen. The increase in Ntotal concentrations in streams’ water below fertilized fields was affected by precipitation (r = -0.31), fertilization rate (r = 0.41) as well as mineral nitrogen reserves in the soil (r = 0.20). Phosphorus concentrations in streams’ water were low and corresponded to a very good streams’ water ecological condition, except in times, when the water inflowing into the fertilized fields was already contaminated with this element. It was determined that an extremely high impact on streams’ water quality below fertilized fields comes from Ptotal concentration in streams’ water above fertilized fields (r = 0.91) as well as from the drainage water inflowing from fertilized fields into the streams (r = 0.71). Neither Ntotal, nor Ptotal pollution was observed in drainage water, because the highest concentrations during the research period were lower than the maximum allowable concentrations by 1.1 and 6.5 times respectively.
Mostrar más [+] Menos [-]Valuation of agricultural externalities: analysis of alternative methods
2014
Novikova, A., Aleksandras Stulginskis Univ., Akademija, Kauno reg. (Lithuania)
The paper focuses on the analysis of agricultural externalities and their valuation methods. Agricultural activity beyond supplying food and fibre, can also be instrumental in forming the landscape, providing natural resources, and preserving biodiversity. Furthermore, agriculture contributes to the achievement of societal goals such as the viability of rural areas and their development, food security, and preservation of cultural heritage. Positive externalities of agriculture assert in the form of public goods, whereas intensive environmentally unbalanced agricultural activity causes damage to the environment. The objectives of this paper are to define agricultural externalities and to analyse methods of their valuation. In order to achieve the research aim, characteristics of agricultural externalities in farming systems have been analysed; evaluation methods of the benefit and cost of externalities in farming systems, revealing their advantages and disadvantages have been examined, and scientific studies on evaluation of externalities have been reviewed. Methods of systemic and logic analysis were applied for analysis of agricultural externalities and their evaluation. The analysis has showed that stated preference methods are commonly used for determination of the positive externalities. The most limited methods are travel cost and hedonic pricing methods, which are suitable only for the evaluation of public goods related to recreation or leisure. For evaluation of negative externalities the external costs of agricultural activity are estimated.
Mostrar más [+] Menos [-]Wellbeing research for rural development
2014
Vaznoniene, G., Aleksandras Stulginskis Univ., Akademija, Kauno reg. (Lithuania)
This article aims to analyse the main features, importance and benefit of wellbeing research for rural development. Wellbeing research, which is becoming more and more important in social sciences discourse and its interrelations with rural development were analysed using analysis and synthesis of scientific literature, logic and systematic analysis, comparison and graphic modelling methods. The interest in the research significantly grew at the end of the 20th century and it is already recognized as a challenge and/or new instrument evaluating the progress and development of society. It should be noted that this direction of research can be adapted to different territorial levels. Wellbeing research is not only about the worldwide (macro level) wellbeing of nations, but also highlights specific features of smaller units like rural areas and their development (micro level). So when implementing the wellbeing research it is important to choose correctly whether objective or subjective wellbeing can be evaluated based on what positive or negative aspects it gives at the local level. This article deals with the main features of wellbeing research and what is common between this research and rural development as well as what benefit they give to rural communities and development. Research results show that benefit of wellbeing research for rural development is important because it allows to get information about the wellbeing situation of rural people, reveals existing problems and positive changes, gives an opportunity to observe how to improve the evaluation of wellbeing and informs rural actors about their role in the wellbeing research and their possible influence on the rural development.
Mostrar más [+] Menos [-]Analysis of theoretical and practical aspects of youth long-term unemployment in Latvia
2014
Grinevica, L., Latvia Univ. of Agriculture, Jelgava (Latvia)
Unemployment and labour market adjustments have featured prominently among the problems of transitional economies. However, the position of young people and their transition from school to work in these new market economies has been virtually ignored. This paper deals with long-term youth unemployment problems and their integration into the labour market as viewed by different authors. The authors consider that the youth long-term unemployment is a global problem. Also, there are analysed statistical data on youth long-term unemployment, and a forecast of the youth unemployment rate for the 1st quarter of 2014 is made. The weakening of the global recovery in the years 2012 and 2013 has aggravated the youth employment crisis when there were no free jobs with adequate requirements for people without education and professional skills. The current situation promotes the trend that was already evident before the economic crisis. Most of young people are now turning to available part-time jobs or choose to study only. The author considers that the youths who have access to different resources will find more stable jobs or make their own businesses after unemployment than those lacking such different kinds of support. In building the education and employment decisions in the transition from school to work, there is a strong evidence of the importance of youths making good initial career decisions and an enduring effect of academic achievement on labour market and education outcomes.
Mostrar más [+] Menos [-]Urea application as a sanitation practice to manage pear scab
2013
Rancane, R., Latvia Univ. of Agriculture, Jelgava (Latvia);Latvian Plant Protection Research Centre, Riga (Latvia) | Vilka, L., Latvia Univ. of Agriculture, Jelgava (Latvia);Latvian Plant Protection Research Centre, Riga (Latvia) | Bankina, B., Latvia Univ. of Agriculture, Jelgava (Latvia)
Several fungicide applications are used to control a pear scab (Venturia pirina Aderh.) on pear (Pyrus communis L.) trees. Minimal chemicals use in fruit-growing constantly has been important condition in the integrated fruit production; therefore, sanitation is recommended to reduce a primary inoculum in orchards. The study was carried out in an integrated pear orchard located in Sigulda district, in the central part of Latvia to estimate if a fall treatment of a pear orchard with urea reduces an amount of pseudothecia and pear scab incidence level the following season. Six treatments trial was arranged in the autumn 2011 on a moderately susceptible pear cultivar ‘Belorusskaya Pozdnaya’. An amount of leaf litter, pseudothecia and incidence level of a disease on leaves and fruits were determined. The results showed that urea application reduced both an amount of leaf litter and a number of pseudothecia. An average amount of leaf litter was 127 leaves per 0.25 square m in a control and 89 leaves in a treatment with urea application. The number of pseudothecia reached 250 pseudothecia per one leaf disc in a control and 160 pseudothecia in a treatment with the urea application, the difference was not significant (p is greater than 0.05). The reduction of disease incidence level on leaves was significant (p is less than 0.05) only in the first assessment of five in total.
Mostrar más [+] Menos [-]Production of bioethanol from starch based agriculture raw material
2013
Jansone, I., Latvia Univ. of Agriculture, Jelgava (Latvia);State Stende Cereals Breeding Inst., „Dižzemes”, Dižstende, Lībagi parish, Talsi municipality (Latvia) | Gaile, Z., Latvia Univ. of Agriculture, Jelgava (Latvia)
Bioethanol can be used for food production and to partially replace fossil fuel. Bioethanol is mainly produced from renewable biomass that contains sugars, starch or lignocellulose. The main raw materials for production of bioethanol are cereals, maize (Zea mays), sugarbeets (Beta vulgaris sacccharifera) and other plant species. During the trial that took place in State Stende Cereals Breeding Institute during a three year period (from 2009/2010 to 2011/2012) we examined the suitability of grain from winter wheat (Triticum aestivum L.), triticale (×Triticosecale Wittm) and rye (Secale cereale L.) for the production of bioethanol. Three varieties of each species were used in the trial. During the trial period the grain yield, the ethanol outcome (L tE-1) and the ethanol yield (L haE-1) were determined. It was established that during three years wheat and triticale provided the highest starch content (more than 700 g kgE-1) of the grain as well as the highest ethanol outcome (L tE-1). These species provided both high grain yield (more than 9 t haE-1 on average) and the highest ethanol yield (3300 – 4665 L haE-1). The choice of variety was also important as both the grain starch content and the grain yield depend on the genotype of the variety.
Mostrar más [+] Menos [-]Metal uptake from contaminated soils by some plant species - radish, lettuce, dill
2013
Stapkevica, M., University of Latvia, Riga (Latvia) | Vincevica-Gaile, Z., University of Latvia, Riga (Latvia) | Klavins, M., University of Latvia, Riga (Latvia)
Plants are components of ecosystem that transfer elements from abiotic to biotic environments. Several elements, such as As, Cd, Hg, Pb, can be considered as food chain contaminants. Simultaneously, some essential micronutrients (e.g., Cu, Cr, Ni, Zn) at high concentrations may become toxic to both, plants and animals. To secure the aim to describe the uptake of metals by food crop species such vegetables, as radish Raphanus sativus L., leafy lettuce Lactuca sativa L. and dill Anethum graveolens L., were grown in soils of various grading composition and type. There were five soil types selected. A part of soils was contaminated with copper sulphate solution at different target concentrations, while another part was contaminated with mixture of metal (Pb, Cd, Cu, Zn) compounds. In half of treated soil samples the solution of humic substances was added. Harvested vegetables were dried, and after wet digestion with nitric acid quantitative analysis of metal concentrations was performed by use of atomic absorption spectrometry. The highest concentration of copper was detected in vegetable samples grown in soils with less organics, thereby indicating the importance of soil organic matter to metal transfer routes and accumulation rates in plants. Analysis of lettuce grown in soils contaminated with the mixture of metal compounds revealed that zinc was a metal absorbed more intensively, but metal uptake and accumulation was less intensive from peat if compared with other soils.
Mostrar más [+] Menos [-]Discussion on ground beetles and rove beetles as indicators of sustainable agriculture in Latvia: review
2013
Gailis, J., Latvia Univ. of Agriculture, Jelgava (Latvia) | Turka, I., Latvia Univ. of Agriculture, Jelgava (Latvia)
Ground beetles (Coleoptera: Carabidae) and rove beetles (Coleoptera: Staphylinidae) as predators of many pests and weeds in every crop are significant elements of integrated pest management. Worldwide studies show that ground beetles reflect different soil tillage methods, crop rotation, chemical and genetic pollution, usage of fertilizers and landscape fragmentation. All these factors are the parameters based on which it is possible to assess agriculture whether it is sustainable or not. Ground beetles also can indicate different farming systems and potentially serve as keystone indicators of pest abundance. Thus ground beetles can be good indicators of sustainable agriculture, but rove beetles have a good potential to do it. Researches on crop dwelling ground beetles and rove beetles have been done infrequently in Latvia. Mainly these are faunistic studies not paying attention to agricultural environmental factor effect to ground beetles and rove beetles. For using ground beetles and rove beetles as indicators of sustainable agriculture in Latvia, studies on these beetles reaction to different farming activities should be done. These studies must occur in different crops and different places of country, because ground beetle and rove beetle reflection to changes of agricultural environmental factors may be crop- and site - or even field-specific. Overview of literature on ground and rove beetles’ ecology in agroecosystems recorded in Latvia, other European countries and Northern America has been used for this study.
Mostrar más [+] Menos [-]Nutritional value and sensory properties of yoghurt enriched with barley grains and malt extract
2013
Beitane, I., Latvia Univ. of Agriculture, Jelgava (Latvia) | Straumite, E., Latvia Univ. of Agriculture, Jelgava (Latvia) | Cinkmanis, I., Latvia Univ. of Agriculture, Jelgava (Latvia)
Growing interest of consumers in healthy eating has provided the development of new range of food. Therefore the task of research was to determine the nutritional value, calculate energy value and investigate the sensory properties of yoghurt samples enriched with flakes from biologically activated hull-less barley grains and malt extract. Results showed that by adding flakes from biologically activated hull-less barley grain and malt extract it was possible to improve the nutritional value of yoghurt, i.e., increased protein, carbohydrate and decreased fat content. The energy value of yoghurt samples enriched with flakes from biologically activated hull-less barley grain and malt extract ranged between 65.96 and 75.72 kcal 100 gE-1, which is significantly lower comparing with mean energy value of commercial yoghurts. The changes of sensory properties were affected by the amount of added malt extract in yoghurt samples. The optimal amount of added malt extract for sensory evaluation in yoghurt samples was determined as 2%. The content of carbohydrate in yoghurt sample enriched with 5% of biologically activated hull-less barley grain and 2% of malt extract was two times lower than commercial yoghurts therefore its energy value was significantly lower. Yoghurt enriched with flakes from biologically activated hull-less barley grain and malt extract could be competitive.
Mostrar más [+] Menos [-]Blood pressure and aortic lumen diameter changes after replacing aorta abdominalis with prosthesis
2013
Malniece, A., Latvia Univ. of Agriculture, Jelgava (Latvia) | Auzans, A., Latvia Univ. of Agriculture, Jelgava (Latvia) | Drevinska, K., Latvia Univ. of Agriculture, Jelgava (Latvia)
The objective of this study was to observe and evaluate the ability of innovative vascular prosthesis, made in Riga Technical University (RTU), to incorporate in a canine model. The research has been performed in Veterinary Medicine Faculty of Latvia University of Agriculture since July 19. 2011. The research was approved by the Food and Veterinary Service of the Republic of Latvia. The research is realized within the framework of European Social Fund co-financed project ‘Establishment of interdisciplinary research groups for new functional properties of smart textiles development and integrating in innovative products’ (ESF No 2009/0198/1DP/1.1.1.2.0./09/APIA/VIAA/148). RTU produced aortic grafts 5-8 mm in diameter and 8 mm to 18 mm long were implanted retroperitoneal in 9 female, 1-3 years old Beagle dogs. Once before and regularly after the surgery, abdominal aortic and vascular graft diameter was measured in cross sections. Blood pressure was measured before and regularly after the procedure. Results show no significant differences in aortic and graft diameter before and 12 months after the operation and there are no significant differences in systolic and diastolic blood pressure before and 6 months after the aortic surgery at a significance level α 0.05. The study shows that the innovative aortic prostheses do not change in diameter and abdominal aorta transplantation surgery does not cause significant variations in blood pressure. Study is continued to find out later reactions to synthetic vascular graft.
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