细化搜索
结果 21-30 的 99
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.
显示更多 [+] 显示较少 [-]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.
显示更多 [+] 显示较少 [-]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.
显示更多 [+] 显示较少 [-]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.
显示更多 [+] 显示较少 [-]Stinging nettle − the source of biologically active compounds as sustainable daily diet supplement
2014
Zeipina, S., Latvia Univ. of Agriculture, Jelgava (Latvia);Pure Horticultural Research Centre, Pure parish, Tukuma municipality (Latvia) | Alsina, I., Latvia Univ. of Agriculture, Jelgava (Latvia) | Lepse, L., Pure Horticultural Research Station, Pure parish, Tukuma municipality (Latvia)
Environmental conditions and climate change on a global scale affects the overall agriculture and food supply. Consumers demand for vegetables with high nutritional value is increasing. Consumers more and more are thinking about a healthy and balanced diet, but it is not easy to provide year-round fresh vegetables. Nettle (Urtica) leaves traditionally are used in early spring as a leafy vegetable in salads and soups. Young leaves before flowering are used for human consumption. Nettle contains a lot of vitamins and biologically active compounds. The research aim was to evaluate different stinging nettle clones, which grow in Pūre village (Tukuma district, Latvia). Samples were collected, when shoots were 10 – 15 cm long. Content of chlorophyll, carotenoids and anthocyanins in five nettle clones leaves were analysed. Biochemical analysis was done in Latvia University of Agriculture, Institute of Soil and Plant Science laboratory. Differences were observed between all clones. Significant difference between genotypes was observed in anthocyanins content, but not in chlorophylls and carotenoids content. Higher anthocyanins content was observed in samples, which grow in places with low nitrogen and phosphorus content. Content of biochemical compounds can influence some metal ions, environmental and other factors.
显示更多 [+] 显示较少 [-]Stinging nettle - the source of biologically active compounds as sustainable daily diet supplement
2014
Zeipina, S., Latvia Univ. of Agriculture, Jelgava (Latvia);Pure Horticultural Research Centre, Pure parish, Tukuma municipality (Latvia) | Alsina, I., Latvia Univ. of Agriculture, Jelgava (Latvia) | Lepse, L., Pure Horticultural Research Station, Pure parish, Tukuma municipality (Latvia)
Environmental conditions and climate change on a global scale affects the overall agriculture and food supply. Consumers demand for vegetables with high nutritional value is increasing. Consumers more and more are thinking about a healthy and balanced diet, but it is not easy to provide year-round fresh vegetables. Nettle (Urtica) leaves traditionally are used in early spring as a leafy vegetable in salads and soups. Young leaves before flowering are used for human consumption. Nettle contains a lot of vitamins and biologically active compounds. The research aim was to evaluate different stinging nettle clones, which grow in Pūre village (Tukuma district, Latvia). Samples were collected, when shoots were 10 – 15 cm long. Content of chlorophyll, carotenoids and anthocyanins in five nettle clones leaves were analysed. Biochemical analysis was done in Latvia University of Agriculture, Institute of Soil and Plant Science laboratory. Differences were observed between all clones. Significant difference between genotypes was observed in anthocyanins content, but not in chlorophylls and carotenoids content. Higher anthocyanins content was observed in samples, which grow in places with low nitrogen and phosphorus content. Content of biochemical compounds can influence some metal ions, environmental and other factors.
显示更多 [+] 显示较少 [-]Yield maturity parameters of hybrid grapevine (Vitis sp.) cultivar ‘Zilga’
2014
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 number of grape (Vitis sp.) cultivars is increasing every year, the focus point of recent grapevine studies are heading to producing high quality fruits for producing quality wine. A field trial with cultivar ‘Zilga’ was established in 2007 at the Estonian University of Life Sciences and in 2010 in a greenhouse. ‘Zilga’ is one of the well adopted cultivars in Estonia, which has been used mostly for producing wine and grown in open field conditions. The aim of the present experiment was to find out the yield maturity parameters of cultivar ‘Zilga’ for red wine in Estonian conditions. Data was collected from the year 2011 to 2013. The bunch weight and °Brix were determined from fresh materials, but all the other biochemical parameters were determined from frozen (-20 °C) grapes. The recommended content (20 °Brix) of soluble solids was not obtained in open field conditions, but reached to 24.1 °Brix in greenhouse conditions in 2013. Titratable acids content was higher than recommended values, ranging from 1.4 to 1.6 mg 100 gE-1 in open field and showing the lowest content (1.2 mg 100 gE-1) in greenhouse conditions. Maturity index values ranged from 117 to 224, and the optimum was reached in two years from three. The highest total phenolics content, 293 mg 100 gE-1 was obtained in 2011, while anthocyanin content was significantly increased in 2013.
显示更多 [+] 显示较少 [-]Analysis of climatic factors in connection with strawberry generative bud development
2014
Kalnina, I., Latvia Univ. of Agriculture, Jelgava (Latvia);Latvia State Inst. of Fruit-Growing, Dobele (Latvia) | Strautina, S., Latvia State Inst. of Fruit-Growing, Dobele (Latvia)
Strawberries (Fragaria× Ananassa Duch.) are widely grown in Latvia, and it is the first berry crop that ripens in summer. In Latvia, climate conditions are very suitable for strawberry growing. Unfortunately, meteorological conditions have become very changeable in recent years. The short day (SD) strawberry cultivars are the most important ones for Latvia, as they initiate flower buds in autumn. For these cultivars it is important to initiate flower buds at the end of September till the end of October. The day length has to decrease less than 14 hours per day to begin this process. In Latvia, the day length below 14 hours per day is at the end of August. The second important limiting factor for initiation of flower buds is the average day temperature, which must be between 10 and 15 °C. The studies on strawberry flower bud initiation in Latvia were done long time ago, on a very small scale and fragmentary. The current paper analyzes the temperature regime during the period of previous ten years (2004 – 2013) in autumn in Dobele in relation to suitability of this climatic factor to the flower bud initiation and strawberry yield next year. The soil surface temperatures during the last ten years in August were about +20 °C, which means that the flower bud initiation could not occur as early as it was described in the previous study.
显示更多 [+] 显示较少 [-]Fertilisation effect on biomass formation of perennial grass used as energy crop
2014
Rancane, S., Latvia Univ. of Agriculture, Jelgava (Latvia) | Karklins, A., Latvia Univ. of Agriculture, Jelgava (Latvia) | Lazdina, D., Latvian State Forest Research Inst. Silava, Salaspils (Latvia)
Bioenergy production growth rates in the recent years are leading to waste – digestate and wood ash amount increases, which are essential to be managed in the most efficient and safe way. In the formation of plant nutrient recycling these waste products are useful to be included in the energy crop fertilisation plan. In order to study the waste products application options for energy crops – reed canary grass (Phalaris arundinacea L.) and festulolium (×Festulolium pabulare) fertilisation trials were arranged in 2012 at the Skriveri Latvian University of Agriculture (LLU) Research Institute of Agriculture. In all fertiliser treatments: wood ash; digestate one time per season; digestate two times per season and mineral fertilisers the same doses of the main plant nutrients (N, P, K) were provided, the missing quantities of elements compensating with mineral fertilisers. To obtain the grass biomass, two cutting regimes were used – two-cut and one-cut harvest system. This article summarizes the findings on the productivity of the 1st year of use grassland swards and sward structure data. The productivity of perennial grass biomass was dependent on the type of applied fertilisers, grass species and cutting regime. In the first production year the highest average dry matter yield (7.30 t haE-1) was produced by reed canary grass. The highest DM yields in average for both grass species were obtained by mowing once per season – in autumn at crop senescence (7.01 t haE-1) and in fertilisation treatments of wood ash (WA) – 8.06 t haE-1 and mineral fertilisers (MF) – 7.24 t haE-1.
显示更多 [+] 显示较少 [-]The efficiency of biogas digestate on grassland compared to mineral fertilizer and cattle slurry
2014
Tampere, M., Estonian Univ. of Life Sciences, Tartu (Estonia) | Viiralt, R., Estonian Univ. of Life Sciences, Tartu (Estonia)
Biogas production from organic wastes is gaining popularity, especially in agriculture, which produces high quantities of organic wastes suitable for anaerobic digestion. Digestate is the valuable by-product of the biogas production that is considered as a valuable fertilizer. The objectives of the experiment conducted from 2012 to 2013 at the Estonian University of Life Sciences were to compare the impact of biogas digestate, undigested (raw) cattle slurry, and inorganic nitrogen fertilizer on grass yield and to assess the fertilizer value of digestate produced from different feedstock. Fertilizers were applied to the grassland rich in low grasses by broadcasting in quantities according to the nitrogen rate of 180 kg haE-1 in three split applications. The application rate of organic fertilizers was calculated based on NH4 -N content. Grassland yield was determined on four treatments: (i) control (no fertilizer was applied), (ii) mineral N-fertilizer (NH4 NO3), (iii) cattle slurry and (iv) cattle slurry digestate. Grass yield was measured three times during the growing period. Our research showed that digestate when applied based on its NH4 -N content is effective fertilizer in grassland. It could be used as a substitute for mineral-N fertilizer, but its efficiency is slightly lower when compared to cattle slurry, due to its lower application amount resulting in lower nutrient and organic matter amount applied to the grassland. Co-digestion of cattle slurry with solid manure, hay and silage does not decrease digestate fertilizer value in grassland, because the addition of other substrate increases digestate DM content.
显示更多 [+] 显示较少 [-]