2017, Vol. 15, No. 5

Selle kollektsiooni püsiv URIhttp://hdl.handle.net/10492/5367

Sirvi

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Determination of mechanical properties of poppy waste pellets
(2017) Kažimírová, V.; Kubík, Ľ; Chrastina, J.; Giertl, T.
The work deals with evaluation of mechanical properties three types of pellet samples produced fro m poppy waste. The pellets were submitted to compressive loading. The compressive loading curves of dependencies of force on strain and force on time were realised. Certain mechanical parameters were determined, namely the diameter of the sample, length of the sample, force at 10% of strain, force in the first maximum of the force – strain curve, strain in the first maximum of the force – strain curve, modulus of elasticity, force in the inflex point of the force – time and force – strain curves and strain and stress in the inflex point of the force – time and force – strain curves. The work lists correlations of mechanical parameters of individual pellet types. The pellet type 1 made only of ground poppy head mass has shown the best results, the pellet type 3 consisting of ground poppy heads after harvest and waste from sieving of poppy seeds in mass proportion 1 : 1 has shown the worst results.
Results of fifteen-year monitoring of winter oilseed rape (Brassica napus L.) production in selected farm businesses of the Czech Republic from the viewpoint of technological and economic parameters
(2017) Šařec, O.; Šařec, P.
The paper presents field trials focused on technological and economic comparison of conventional tillage (CT) and reduced tillage (RT) technologies of soil cultivation and drilling of winter oilseed rape (Brassica napus L.). During fifteen production years starting in 2001/02, trials were set up in 520 fields of around 40 farm businesses located in all of the districts of the Czech Republic. With respect to average seed yields, no significant differences were proved with respect to tillage systems, to the application of organic fertilizers and to the fertilization during sowing. Irregular distribution of trial fields into the individual production areas influenced the outcomes thou. Concerning winter rape seed yields, costs per production unit, and earnings per hectare, the most suitable production area proved still to be the potatoes one, but particularly over the recent period also beet production area. The corn production area produced, despite some exceptions, worst results. Over the fifteen-year time, the average oilseed rape yield of all 520 monitored fields was 3.72 t ha–1 . Reduced tillage attained average yield of 3.73 t ha–1 , i.e. matched almost exactly the one of 3.70 t ha–1 attained by conventional tillage. Unit production costs realized by conventional tillage surpassed by 4.1% those gained by reduced tillage. Related earnings per hectare were on the other hand lower by 17.0%. With respect to fuel and labour consumption, reduced tillage brought significant savings reaching in average 20.2%, respectively 24.0%. In terms of yields, reduced tillage with deeper soil loosening proved repeatedly favourable results.
Effect of slurry lagoon redesign on reduction of ammonia emission during livestock manure storage
(2017) Aboltins, A.; Priekulis, J.; Aboltina, B.; Melece, L.
In accordance with the international and EU aims to reduce emissions of ammonia and other air pollution substances farm manure management, including its storage, especially for the animal breeding sector, is one of the most essential stages. One of the preventing steps is covering of the slurry lagoons. The most effective – hard covering can be provided only after the lagoon is constructed. The aim of the research: to develop methodology for calculations of emission reducing lagoon design volume and surface area. In the result of the theoretical research the possibilities of reducing the reflection surfaces at the same capacity of the lagoon have been discovered, as well as the changes of the reflection surface area, if instead of one lagoon several lagoons with less volume are installed and sequential filling of these lagoons is ensured. The article presents the calculation algorithms obtained during the research and recommendations for construction of low emission lagoons.
Influence of tied ridging technology on the rate of surface runoff and erosion in potato cultivation
(2017) Vejchar, D.; Stehlik, M.; Mayer, V.
Water management and securing good condition of soil is becoming an important factor in agriculture one of the reasons being adaptation to the increasingly frequent extremes in weather. Tied ridging technology enables to reduce significantly the loss of water and soil from arable land. The effect of a tied ridger mounted on 2-row planter and effect of 6-row tied ridger on basin renewal was tested in potato cultivation on plots of land with length of 10 m. During entire season lasting 135 days the technology helped achieve 78% of efficiency in reduction of surface water runoff and 88% of efficiency in case of soil loss. In the case of furrows with only tied ridging the water retained represented additional 15% of total water from rainfall (37.5 mm of 250 mm) over untreated furrows. In the case of basins formed in furrows with wheel trails the water retained represented 15% of total water from rainfalls in the trail. This water retained on the land would have otherwise flown off and would not have been utilized without this technology. The renewal of dams after 1/3 of the season increased significantly the efficiency of this technology. The technology of tied ridging significantly contributes to sustainable agriculture management.
Quality evaluation of local apple varieties: physicochemical and antioxidant proprieties at harvest and after cold storage
(2017) Bartolini, S.; Ducci, E.
A wide apple germplasm is present in Italy in which numerous local genotypes of specific cultivation environment have to be still evaluated for fruit quality attributes. This is the case of a long-established fruit area located in central Italy (Tuscany) where several ancient apple varieties survive with the perspective to be re-introduced for their excellent quality. The objective of this work was to determine over a 2-year period the physicochemical traits, total antioxidant capacity (TAC), and polyphenols (TP) content of three old local apple varieties: ‘Paganina’, ‘Paradisa’ and ‘Rosa’. These characteristics were also assessed after 90 and 150 days at 4 °C cold storage, in normal atmosphere refrigerated cellars. For comparison purpose, the commercial apple cultivar ‘Fuji’ was considered. In general, the old varieties showed valuable quality properties, particularly due to a greater antioxidant power of fruits, although a variability between the two crop seasons, characterized by different weather conditions, was observed. After a dry summer, ‘Rosa’ showed very high TAC and TP values (2-fold higher than other varieties) that, after longperiods of cold storage, markedly decreased. These losses were not so noticeable in the others, suggesting a tendency to maintain a major stability during storage. These findings could meet the preference of demanding consumers for healthier foods who appreciate fresh fruits with protective properties by free radicals scavenging activity. Moreover, farmers who are focused on nearby and niche markets could have interesting in these local varieties to promote their valorization.
Prevention the impact of chemicals on the health of workers in fibreglass industry
(2017) Urbane, V.; Vilcane, I.; Tint, Piia; Ievins, J.; Jemeljanovs, V.; Birgere, L.
Most of the chemicals make our everyday life easier and safer. However, there are a lot of new emerging risks connected with chemicals causing damage to people’s health and environment. The results of the investigation: the chemical exposure index (EI) is between 0.16 to 25.98 (the last determined by the mould spray-up, outside of the protective masks). The air pollution index determined was between 16 to 760%. The ventilation rates for the remove of the volatiles from the workplace air are settled, the possibilities for substitution of hazardous chemicals to less hazardous are presented. When the concentration of a volatile is measured under the protective mask, which has a new filter, the tested substance concentration is lower that under the mask with an old filter, although the differences between these two were rather small. When the volatiles were measured under the protective mask, the concentrations of tested substances met the requirements.
Juvenile growth and frost damages of poplar clone OP42 in Latvia
(2017) Sēnhofa, S.; Neimane, U.; Grava, A.; Sisenis, L.; Lazdina, D.; Jansons, A.
Short rotation plantations in the northern Europe are commonly established using poplar clone OP42 (Populus maximowiczii Henry × P. trichocarpa Torr. and Gray). We assessed its growth and suitability to the climate in central part of Latvia at juvenile age. Trees that had formed single stem were significantly higher (121 ± 2.5 cm), thicker (7.1 ± 0.48 mm) and had longer branches (32 ± 1.5 cm) than trees that had formed multiple stems. In beginning of the second growing season all trees had died stems and 19.6% of them formed new shoots from the ground level. The sprouting trees had random spatial distribution in the field. Regardless of the number of stems, the sprouting trees were significantly lower (110 ± 3.9 cm) than the dead trees (119 ± 2.0 cm). During the repeated assessment about one month later, proportion of the sprouting trees increased up to 44%, but the detected relations between measured traits of sprouting and dead trees remained. Clone OP42 had serious frost induced damages also in autumn phenology experiment (96% trees with severely damaged leaves). Our results suggest that frost prone sites are not suitable for establishment of plantations of OP42 clone.
Study of clonal variation of 'Bidaneh Ghermez' grapevine cultivar in Iran
(2017) Ataei, R.; Gholamhoseini, M.; Nejatian, M. A.; Golmohammadi, M.
Grapevine (Vitis vinifera L.) is a well - known plant including different cultivars and clones. In spite of the extensive works at the cultivar level, identification and determination of clonal genetic variation has remained as a challenge. To assess the genetic variation between clones of grapevine cv. 'Bidaneh Ghermez', 20 selected clones were analyzed for cluster weight (CW), cluster length (CL), cluster width (CWI), berry weight (BW), berry length (BL), berry width (BWI) and total soluble solids (TSS) in randomized complete block design with three replications. Analysis of variance reveale d considerable genetic variation for all measured traits (except cluster width) among clones. Cluster analysis, discriminant function analysis and principal component analysis (PCA) showed same results and all clones assigned in 2 groups. First group was including 9 clones and second group was including 11 clones. Overall, our results indicated C7, C10, C12 and C14 clones were best clones and have potential to introduce promising clones for stablishing new vineyard with high yield.
Production and analysis of non-traditional beer supplemented with sea buckthorn
(2017) Adadi, P.; Kovaleva, E.G.; Glukhareva, T.V.; Shatunova, S.A.; Petrov, A.S.
In recent years, there has been a growing demand for non-traditional beer (craft) with different flavours hence the main aim of this research is to produce beer with sea buckthorns (SBT). Brewing software BeerSmith was used to design the Kölch beer. After one month of primary fermentation, SBT were sanitised and crashed before adding into the green beer. Carbonation was done using keg with 1.8 bar of carbon dioxide. Physicochemical properties, microbial load and sensory evaluation of Kölch fruit beer (KFB) were determined. All the physiochemical parameters measured were significantly (P < 0.05) influenced by the fermentation time. The pH dropped from 5.8 ± 0.1 to 3.9 ± 0.1 toward the end of the fermentation. There was no microbial growth when KFB was inoculated in the media. °Brix likewise decreases from 13.3 ± 0.43 to 3.86 ± 0.25. There was a change in the colour of the wort throughout the fermentation from 11.2 ± 0.44 to 32.5 ± 0.56 EBC. A decrease from 1.48 ± 0.02 to 0.86 ± 0.02 mg maltose per 100 ml in the reducing sugar was observed during the entire period of fermentation. A total of 32 volatile compounds were identified. All assessed sensory variables of KFB were significantly different (P < 0.05) and preferred by the panellists, however, foaminess and clarity of KFB should have to be improved. KFB showed higher DPPH radical scavenging activity as compared to other types of beer examined due to biologically active substances contributed by SBT.
Effects of Irrigation water salinity on evapotranspiration and spinach (Spinacia oleracea L. Matador) plant parameters in Greenhouse Indoor and Outdoor Conditions
(2017) Ünlükara, A.; Yurtyeri, T.; Cemek, B.
Response of spinach to irrigation water salinity under greenhouse indoor and outdoor conditions was investigated in this study to reveal different weather conditions on salinity tolerance of the plant. For this purpose, saline waters at six different salinities (0.65, 2.0, 3.0, 4.0, 5.0 and 7.0 dS m-1 ) were applied to spinach (Spinacia oleracea L. Matador) grown in pots. Soil salinity increased linearly with increasing salinity of irrigation water. Threshold salinity is 2.35 dS m-1 and yield lost slope after this threshold is 3.51% for indoor and threshold salinity is 2.83 dS m-1 and yield lost slope is 3.3% for outdoor. Salinity harmful effect on spinach yield is higher for indoor conditions than for outdoor conditions because of higher indoor temperatures. These results apparently showed that spinach salinity response could change with changing weather conditions especially for temperature. Yield response factors (ky), which is the ratio of relative evapotranspiration decrease to relative yield decrease, were close in the cases of irrigation water salinity in greenhouse outdoor and indoor (ky = 2.4 and 2.1), respectively. Considerable water consumption decreases because of salinity were determined. Every 1 dS m-1 increment in soil salinity caused about 1.35% water consumption decrease for spinach. Therefore, depressing effect of salinity on water consumption should be considered in irrigation and salinity management to prevent excess saline water application and to protect environment.
The advantage of Decision Support System for managing spring barley disease in Estonia
(2017) Sooväli, Pille; Koppel, Mati; Lauringson, Enn; Talgre, Liina
A Decision Support System (DSS) I - Taimekaitse focusing on use of timely applied and reduced fungicide rates in control of cereal diseases has been tested in field trials since 2003 . We compared the conventional treatment and the DSS - based spray practices in 18 field trials in five agricultural locations over 7 - year period. Efficacy of the control of net blotch caused by Pyrenophora teres (Drechsler, am Drechlera teres Sacc. Shoem), the main fungal disease in spring barley has been tested to determine the economic advantage of DSS use. Compared with the conventional spray practices, the advantage I - Taimekaitse resulted in reduction of application doses by 30 to 60% of the registered rate. According to I - Taimekaitse , the fungicides were applied mainly between heading and flowering growth stages (GS 55 – 65), whereas traditional routine spraying is commonly made at booting (GS 37 – 49) . The experiment clarifies the cost - benefit of using DSS - based approach in barley disease management with average yield increase above the control in 12.8% and above the conventional treatment in 14.1%. I - Taimekaitse gave competitive disease control and average yield output reduction compared with conventional practice by 9%. In general the Treatment Frequency Index applied in conventional treatment was 0.65 and in DSS 0.41. Although the cost of treatment expense in DSS was 20% less compared with conv entional practice, the performance of conventional used spray practices was outstanding in economic return.
Research on solid biofuels from cotton waste biomass – alternative for Tajikistan’s energy sector development
(2017) Akhmedov, S.; Ivanova, T.; Krepl, V.; Muntean, A.
An increasing awareness of the negative environmental cost associated with the combustion of fossil fuels and concerns over the geopolitical instability of the main oil producing regions is driving the development of renewable energy sources and biofuels. Use of solid biofuels made of different types of biomass became perspective alternative to conventional fuels in many countries. Such positive indicators as low cost of the final product that meets the quality of standards, not capital intensive production, possibility of producing briquettes/pellets from almost any agricultural waste or combination of raw materials are undoubted advantages of biomass based fuels. The main challenges for Tajikistan’s energy sector, which is depended on energy imports, are: to increase energy supply through better exploitation of hydropower and other renewable energy sources such as wind, solar and primary biofuels. Within the agricultural sector of Tajikistan, which is highly agrarian country, cotton accounts for 60% of agricultural output. According to the Ministry of Agriculture of Tajikistan 199,400 hectares of lands have been allocated to cotton cultivation in the year of 2014. Plenty of unused cotton residual biomass could be effectively utilized for winter heating in rural areas. The main focus of the research was to investigate and assess physical, chemical and mechanical properties of pellets and briquettes produced form cotton waste biomass.
Analysis of Arabidopsis defensin-like genes and ovule development during fertilization and Fusarium infection
(2017) Spalvins, K.; Blumberga, D.
Defensins are small, highly stable antimicrobial peptides. Many defensin-like (DEFL) peptides found in flowering plant Arabidopsis thaliana are believed to have role in either natural immunity or cell-to-cell communication during fertilization. However, little is known about the DEFL peptides and their functions during these events. The goal of this work is to investigate the genes encoding selected DEFLs by observing their expression patterns during fertilization and Fusarium graminearum infection. According to the results 4 selected genes of interest (GOI) are downregulated after fertilization and infection and mock treatments are causing degradation and delay of development in treated ovules.
Work strain predictors in construction work
(2017) Roja, Z.; Kalkis, H.; Roja, I.; Zalkalns, J.; Sloka, B.
The aim of this study was to predict the work strain indicators for construction workers and to work out measures for prevention of strain at work. Subjective and objective research methods were utilized in the research, including survey, work intensity measurements (Borg Scale), work strain index, fatigue index and work ability index determination, objective blood pressure and pulse measurements. Statistical analysis with significance calculations was carried out. The limitation of this study is the small number of subjects involved in the research. Subjective evaluation of fatigue index and strain index resulted in moderate and somewhat hard work heaviness categories accordingly to Borg Scale. Measurements of heart rate, blood pressure approved work strain of employees of both professions does not exceed the admissible heart rate limit during physical load. The research proved that the strongest work strain predictors were connected with psycho-social risks rather than with physical ones.
Qualitative classification of mulchers
(2017) Hnilica, R.; Kotus, M.; Jankovský, M.; Hnilicová, M.; Dado, M.
Mulchers are helpful in forest establishment and tending. Numerous mulchers are available, so buyers can become disoriented when choosing one. This paper was aimed at creating a classification of mulchers based on the evaluation of the most important parameters: weight, required engine performance, and mulching diameter. Through ANOVA, and regression and correlation analyses of our database, we created six machine classes, devised their upper limits, and assigned mulchers to the classes. Class K1 (weight up to 1,300 kilograms; performance up to 75 kilowatts; mulching diameter up to 22 centimetres) was the most popular one with 88 mulchers. It was followed by class K2 (1,800 kilograms; 100 kilowatts; 27 centimetres) with 61 mulchers, class K4 (3,200 kilograms; 175 kilowatts; 41 centimetres) with 44 mulchers, class K3 (2,300 kilograms; 125 kilowatts; 31 centimetres) with 34 mulchers, class K5 (4,100 kilograms; 225 kilowatts; 51 centimetres) with 18 mulchers, and class K6 (no upper limit) with nine mulchers.
Unified client service centres for rural development and smart governance in Latvia
(2017) Sunina, L.; Rivza, B.
Nowadays rapid increase of technological environment allows residents to be more mobile, choose working place, different from one’s place of residence, start a new business or transfer company to rural areas, thus promoting polycentric development of a territory and increasing capacity of rural territories. It means that government should think of smart governance and service provision, providing different government services at one place. From June 2015 until December 2015, under the concept of improvement of public service system, the government of the Republic of Latvia established 75 unified state and local government customer service centres. Service centres operate on a local basis and in accordance with the uniform principles, provide customer with one place to access multiple public services. The objective of the present article is to evaluate the necessity and current activity of unified customer service centres and their contribution to smart governance of the country. The necessity for unified client service centres in the rural areas were therefore assessed with the analysis of attributable data, theory on establishment of such centres, and residents’ survey, which showed that a big part of customers of the present centres are residents of neighbouring towns and cities where the regional governmental and local institutions are located, but they are attracted by the possibility to receive all the necessary services at one time.
Substantial factors influencing drivers’ comfort in transportation
(2017) Zewdie, R.; Kic, P.
Research shows that driver stress is associated with workload and fatigue, and an inappropriate microclimate in the driving cabin can have an impact on overall driver’s safety. The aim of this scientific study is to examine whether driver stress, across various urban and field drive conditions, can affect performance in a confined environment and whether the natural breathing process can also compound these effects and aggravate health hazards. This paper will address the influencing parameters associated with driver comfort of everyday job occupations in the urban communication network of Prague city public transport. In this research paper the authors will characterize cardinal components directly accountable to the safe operation elements; the concentration of carbon dioxide (CO2) and the relative humidity (Rhi) in the driving cabin, affecting the contentment of the drivers comfort while performing their duties. Similar inquiries were carried out on ventilation emphasis and air intake impact in drivers’ cabin, recommending a design to minimize safety problems associated with comfort. Data on the concentration of carbon dioxide and internal relative humidity in the respective cabins have been collected carefully for detailed analysis. This research paper is the outcome of these findings.
Instrumental and sensory evaluation of seven apple (Malus domestica Borkh.) cultivars under organic cultivation in Sicily
(2017) Farina, V.; Gianguzzi, G.; Mazzaglia, A.; Sortino, G.
In this trial we examined the quality of 7 clones belonging to more diffused apple polyclonal varietal groups, using chemical/physical and sensory analyses during two consecutive years. Galaxy, and their ameliorative clones Gala Annaglò® and Dalitoga (Gala clones) that ripen in summer, Erovan* Early Red One® and Scarlet Spur*-Evasni® (Red Delicious clone), Corail Pinova and its ameliorative clone RoHo 3615 * Evelina® that ripen in autumn were studied. Gala Annaglò® is interesting for the fruit size and peel color, Dalitoga for the early ripening and Galaxy for the crunchiness and consistency. All the Gala clones reached very high total solid soluble content confirmed by the panel judgment of the sweetness and acidity descriptors. The Red Delicious clones confirm the larger size and the high colorimetric standard of all covered red fruits; the new clone Scarlet Spur*-Evasni® reached an interesting fruit size and peel colour intensity and uniformity, and the best total solid soluble content to total acidity ratio confirmed by the sensory descriptors of acidity and sweetness. Moreover, it reached very high values of crunchiness, consistency and interesting values of apple flavour, honey flavour and fruit flavour. The ameliorative clone RoHo 3615*Evelina® was characterized by well uniform and intense coloured fruits and a more balanced total solid soluble content to total acidity ratio, and interesting values of crunchiness, consistency, apple flavour, honey flavour and fruit flavour. This study confirms the relationship between instrumental and sensory analysis.
Dimethyl ether as a renewable fuel for diesel engines
(2017) Zeman, P.; Hönig, V.; Procházka, P.; Mařík, J.
The area of automotive fuel, or fuel components, which can be produced from biomass also includes dimethyl ether, otherwise known as DME. The issue of the use of DME as a fuel is one which has been monitored until recently. Biomass can also be used as the raw material for the production of DME. DME has therefore replaced the previously-used CFCs (chlorofluorocarbons), which are now banned for their role in dangerous levels of ozone depletion. With regard to its physical properties and combustion characteristics, it is currently expected that DME will soon apply significantly as a fuel in the municipal sector and in households, and as an alternative fuel for motor vehicles with diesel engines. DME is a suitable fuel for diesel engines and can be considered as one of the most promising diesel fuel replacements. DME is a suitable fuel for diesel engines mainly due to its low self-ignition temperature and good cetane figures. It is well miscible with most organic solvents and because the polar solvent is water-immiscible. The advantage is its high levels of purity, and its being free of sulphur, nitrogen, or metals. The physical properties of DME are very similar to the physical properties of LPG. DME requires relatively complex and costly fuel accessories, but the original compression ratio of the diesel engine is maintained. A diagram of the fuel system is illustrated in the paper. The paper analyses the dependence of vapour pressure on temperature, the dependence of the density on temperature, kinematic viscosity, the flash point, the boiling point, and the solubility of water. The objective is to evaluate this interesting energy source for applications in diesel engines.
Assessment of different growing conditions for enhanced postharvest quality and shelf-life of leaf lettuce (Lactuca sativaL.)
(2017) Lee, J.-S.; Nath, U.K.; Goswami, G.; Nou, I.S.
Lettuce is the most important leafy vegetable. It is exclusively used as freshly raw form but sometime also as cooked. However, its quality depends on several pre- and postharvest factors. The effects of growing conditions and cultivars on the postharvest quality of leaf lettuce were investigated. In this experiment the interaction of variable factor; like growing conditions and fixed factor; cultivars are also observed. The leaf lettuce cultivars ‘Cheongchima’, ‘Cheongchuckmyeon’, ‘Geockchima’ and ‘Geockchuckmyeon’ were grown under favourable (natural condition) and unfavorable growing condition (with excess soil water and 50% shading) to evaluate their shelf-life and postharvest qualities. Plant height and the number of leaves were significantly varied in different growing conditions and by cultivars. In addition, fresh weight was affected by only growing condition, whereas leaf thickness was influenced by cultivars, growing conditions and the cultivars influenced the degree of fresh weight loss and respiration rate during postharvest storage. However, the postharvest storage qualities differed with cultivars and in combination with growing conditions.Leaf thickness and quality of leaf lettuce before and after harvest were also varied by cultivars and growing conditions. It could be concluded that postharvest leaf lettuce quality remains acceptable when growing under excess soil water with 50% shading.

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