2018, Vol. 16, No. 3

Selle kollektsiooni püsiv URIhttp://hdl.handle.net/10492/5376

Sirvi

Nüüd näidatakse 1 - 20 31

Evaluation of the RTK receiver’s capability of determination the accurate position
(2018) Kadeřábek, J.; Shapoval, V.; Matějka, P.
The main aim of this experiment was to compare low - cost RTK receiver, that possible can be used for precise agricultural application, another that is currently used for these applications and the third one that suits for static measurement the most and gives the reference point for results comparison. The main idea of this research was to compare the measured positions during static measurement of RTK receivers. Were discovered that the receiver Trimble 750 was not able to work in fix mode (mode when the RTK receivers are capable to measure the most accurately) for the whole time. This fact affects the results from whole measurement and showed th at errors were a little higher than producers specifies. The low - cost receiver u - Blox C94 - M8P showed satisfying results when in most cases it was capable to solve the problem of ambiguity integer phases. The main parameters in this work that were counted a nd summarized were: accuracy, precision, RMS error, system status ratio and number of satellites.
Anaerobic co-fermentation of molasses and oil with straw pellets
(2018) Dubrovskis, V.; Plume, I.; Straume, I.
The average grain and straw production in Latvia is increasing in last decade. Straw is not always managed properly and its utilisation in biogas plants can be considered as an alternative. Straw is not the best feedstock for methane production, because it has high C/N ratio. Co - fermentation with other biomass with higher N content can improve the methane production. Purpose of investigation is to evaluate the wheat straw pellets biomass suitability for production of the methane and effect of its co - fermentatio n with molasses, fried sunflower oil and catalyst Metaferm. The anaerobic digestion process for biogas production was investigated in 0.75 L digesters, operated in batch mode at temperature 38 ± 1.0°C. The average biogas yield per unit of dry organic matte r added from digestion of wheat straw pellets was 0.540 L g - 1 DOM and methane yield was 0.285 L g - 1 DOM . Average biogas yield from co - fermentation of wheat straw pellets and molasses was 0.777 L g - 1 DOM and methane yield was 0.408 L g - 1 DOM . Average biogas yie ld from fermentation of wheat straw pellets with 1ml Metaferm was 0.692 L g - 1 DOM and methane yield was 0.349 L g - 1 DOM . Average biogas yield from co - fermentation of wheat straw pellets and sunflowers oil was 1.041 L g - 1 DOM and methane yield was 0.639 L g - 1 DOM . All investigated biomasses can be used for methane production.
Criteria of design for deconstruction applied to dairy cows housing: a case study in Italy
(2018) Leso, L.; Conti, L.; Rossi, G.; Barbari, M.
This work aims at presenting the design process of a new barn for dairy cows. Project embraces several concepts that are rather new to the dairy industry and will deeply affect its environmental, economic and social sustainability. The barn will be built o n a green field site located in Cervasca (CN) in the region of Piedmont. Building has been designed applying the emerging principle of "design for deconstruction" extensively. A series of constructive solutions was developed allowing for complete end - of - li fe disassembly and reuse of building materials. Structural system will consist of locally sourced timber connected by steel joints. Foundations will be realized by means of chestnut wood piles driven into the ground. The employment of an alternative housin g system for dairy cows based entirely on cultivated pack will allow limiting the use of cast - in - place concrete, which is largely employed in conventional dairy barns. The cultivated pack needs a large space per cow leading the building to be particularly extended. The large covered area combined with the high snow load of the building site posed several challenges. Accumulation of snow on the roof would increase dramatically the structural load and therefore construction costs. Therefore, the building will consist of several 12m - large modules with 4m free space between them. Given the unusual shape of the barn and the limited use of concrete for flooring, the development of efficient systems for livestock management required the study of dedicated solutions . A first module, already realized to collect useful information for final design, is described.
Optimizing the sample size to estimate growth in I-214 poplar plantations at definitive tree density for bioenergetic production
(2018) Marziliano, P.A.; Russo, D.; Altieri, V.; Macrì, G.; Lombardi, F.
In Europe, over the last decades, the arboriculture for woody biomass production has significantly expanded, often using poplar plantations. In order to maximize prod uction, the flexibility of the cultivation algorithms becomes necessary. For this reason, it is necessary to apply monitoring tools for the evaluation and estimate of the wood productions, without significantly affect the production costs. In particular, f or the estimate of the productions, the choice of the sample size is of particular importance. The aim of this study was to verify a simplified sampling approaches in poplar plantations characterized by constant tree density. The research was conducted in a poplar plantation on the Tuscan hills (Italy). The surveys were carried out each year for 13 years, from 4 to 16 years old. Through different statistical techniques, the change in the social position of each tree over time was evaluated. The results show ed that the social position of each tree has been characterized by the first years after the plantation. Consequently, the estimate of the productions can be carried out by analysing the diameter increment of 10% of the trees, included in the diameter clas ses around the medium - sized tree at the time of the survey. This study provided a valid method for forest managers characterized by a simplified approach useful to estimate the growth and yield of hybrid poplars. This method will permit reliable biomass es timates, but also a reduction of the costs in the sampling activities in the field.
Using the FEM model for design the heat treatment of an agricultural tools
(2018) Kešner, A.; Chotěborský, R.; Linda, M.; Hromasová, M.
Agricultural tools need mechanical properties such as abrasive wear, hardness and toughness. These mechanical properties are achieved by choosing a suitable steel and subsequent heat treatment of the steel. Phases of the microstructure affects the final steel properties. The phase composition in the steel is influenced with the designing of the heat treatment. 25C rMo4 steel was investigated for the production of agricultural tools. The heat treatments ware designed for different cooling conditions. The salt bath was used to cooling as a medium with subsequent cooling on the water or in the air. The FEM method was u sed to designing the heat treatment conditions. The Johnson - Mehl - Avrami - Kolmogorov equation and the Koistinen - Marburger equations were used to prediction the microstructure phases. The microstructures were verified with experimental measurements. The ASTM G65 method was using for abrasion resistance tests. The results show that this procedure can be used to designing parameters of heat treatment of agricultural tools.
Effect of alternative sources of input substrates on biogas production and its quality from anaerobic digestion by using wet fermentation
(2018) Krištof, K.; Gaduš, J.
The aim of the study was to confirm the suitability of alternative input substrates for production of biogas in order to decrese the need of utilization of high quality maize silage. All of the experiments were conducted by employement of wet fermentation process in mesophilic conditions (temperature in fermentor 40 ± 1 °C ) in experimental fermentor with volume 5 m 3 . The exp eriments were realised in operating conditions of biogas station designed for utilization of agricultural biowaste. The experiments were divided into two alternatives (I and II cycle) and one controle input substates. In the first alternative (I cycle) was daily dosage formed by 33 kg of Amaranth and 250 L of controle manure mixture. In this cycle, more than 3 – times greater specific production of biogas was observed with average methan content 63.9% in comparison with controle manure mixture (80 : 20%, liquid manure and manure). In the second alternative (II cycle) was daily dosage formed by 19.5 kg of sugar beer cuts, 3.3 kg of maize silage, 1.9 kg of oil - seed rape moldings, 2.5 kg of glycerine and 250 L of controle manure mixture. In this cycle, more than 5. 9 – times greater specific production of biogas was observed. The decrease in averare methan content 55.1% however also decrease in average content of hydrogen sulphide (128 ppm ) was observed as well. An unquestionable advantage for both tested alternative m ixed substrates was increase in biogas production and its quality in comparison with control substrate based on manure. At the basis of these findings can be concluded that both tested alternative input substrate mixtures are suitable as co – fermentation su bstances with great potential to increase the biogas production and its quality in case of wet fermentation processes.
Agricultural residues in Indonesia and Vietnam and their potential for direct combustion: with a focus on fruit processing and plantation crops
(2018) Brunerová, A.; Roubík, H.; Brožek, M.; Velebil, J.
Energy consumption in Indonesia and Vietnam has grown rapidly in recent decades. To meet the energy needs of both countries, a higher utilisation of waste biomass sources may represent an adequate solution. Investigated samples represent major crop residues (waste biomass) originating mainly from the agriculture sector of the selected countries. Herbaceous waste biomass from Indonesia is, namely, cassava stems and root peelings ( Manihot esculenta ), coffee leaves ( Coffea arabica ), cacao leaves ( Theobroma cacao ), banana leaves ( Musa acuminata ), bamboo leaves ( Bambusoideae spp.) and aloe vera leaves ( Aloe vera ). Furthermore, fruit and aquatic waste biomass originating from Vietnam is, specifically, sugarcane bagasse ( Saccharum officinarum ), durian peelings ( Durio zibethinus ), rambutan peelings ( Nephelium lappaceum ), banana peelings ( Musa acuminata ), water milfoil ( Myriophyllum spicatum ) and water hyacinth ( Eichhornia crassipes ). All mentioned types of waste biomass were subjected to proximate and calorimetric analysis: moisture, ash and volatile matter contents (%) and higher and lower heating values (MJ kg – 1 ). Obtained values indicated the highest level of ash content in fruit bioma ss samples in the case of sugarcane bagasse (0.84%), in herbaceous biomass in the case of cassava stems (3.14%) and in aquatic biomass in the case of water hyacinth (14.16%). The highest levels of lower heating values were achieved by following samples (be st samples from each biomass type): cassava stems (17.5 MJ kg – 1 ); banana peelings (17.3 MJ kg – 1 ) and water hyacinth (12.8 MJ kg – 1 ). The overall evaluation of all observed samples indicated that the best suitability for energy utilisation by direct combusti on of investigated representatives is fruit waste biomass, followed by herbaceous waste biomass and then aquatic waste biomass.
Assessment of soil electrical conductivity using remotely sensed thermal data
(2018) Křížová, K.; Haberle, J.; Kroulík, M.; Kumhálová, J.; Lukáš, J.
Detection of heterogeneity (crop, soil, etc.) gained a lot of importance in the field of site - specific farming in recent years and became possible to be measured by different sensors. The therma l spectrum of electromagnetic radiation has a great potential today and experiments focused on describing a relation between canopy temperature and various vegetation characteristics are conducted. This paper was aimed to examine the relation between canop y temperature and electrical conductivity as one of staple soil characteristics. The related experiment was undertaken in Sojovice, Czech Republic, within an agricultural plot where winter wheat was grown in 2017 growing season. The examined plot was compo sed of three sub plots and 35 control points were selected within this area which the data were related to. A canopy was sensed by UAV (eBee carrying thermoMAP (FLIR TAU2) camera). Soil conductivity data were collected by terrestrial sampling using EM38 - MK 2 Ground Conductivity Meter in 1 m depth and 2 m sampling point distance. This dataset was later interpolated using the kriging method. The correlation analysis results showed a strong negative correlation between conductivity and thermal data ( - 0.82; p < 0.001 ). When comparing conductivity with NDVI representing the aboveground biomass, there was an opposite trend but also strong result (0.86; p < 0.001 ). Correlation coefficient of thermal data and NDVI comparison was - 0.86; ( p < 0.001 ). These preliminary results have a potential for further research in terms of soil characteristics studies.
Evaluation of the fuel commercial additives effect on exhaust gas emissions, fuel consumption and performance in diesel and petrol engine
(2018) Janoško, I.; Kuchar, P.
The paper deals with the impact assessment of the additives used in diesel and petrol fuel to improve the power and emission parameters of the vehicle and its consumption. The usage of additives in engine fuels have an increasing tendency. The manufacturers claim that ad ditives have positive impact on engine operating parameters, cleaning the fuel supply system and decreasing fuel consumption by improving the engine combustion process. Based on the above statements, measurements were performed to determine change in the e ngine parameters utilising additives. Measurements were performed under laboratory conditions on the MAHA MSR 500 test bench (dynamometer) to simulate free driving cycle selected by authors, which were carried out at constant engine speeds and constant loa d. Focus have been given on tracking of the vehicle's external speed characteristic and measurement of selected parameters: CO, HC, O 2 , fuel consumption (petrol engine) and smoke, fuel consumption (diesel engine). Resulting values of the driving cycles mea sured before and after additives application have been then compared. The result of experiment confirmed that tested fuel additives improved performance and torque depending on engine mileage and fuel type. Tested diesel engine with the higher mileage (app rox. 388 k km ) showed significant increase in power (cca 3 . 57 % ) and torque while in newer petrol engine (approx. 73 k km ) improvement has not been measured. Emissions were improved in both engines. Difference has been also measured in fuel economy as in pe trol engine consumption insignificant increased while in the diesel engine it decreased. This paper brings new complex view on energetical and emission changes in internal combustion engines.
Molecular genetics analysis of milk protein gene polymorphism of dairy cows and breeding bulls in Latvia
(2018) Smiltina, D.; Grislis, Z.
Milk protein is the most valuable component of milk from a dietary point of view. More than 95% of ruminants’ milk proteins are coded by six structural genes: two whey proteins (α – lactalbumin and β – lactoglobulin) and four caseins (α S1 – and α S2 – caseins, β – casein, κ – casein). The object of the research was the genetic polymorphisms of milk protein genes in populations of cows and breeding bulls of milk producing breeds in Latvia. The aim was to promote cow breeding in Latvia by developing and testing mo lecular genetics analyses for future quantity and quality analysis of the dairy cows’ population in Latvia, based on the research of genes encoding milk protein polymorphism. In methodology the molecular markers were chosen which would be suitable for char acterization of polymorphism of five milk protein genes in the population of dairy cows reared in Latvia. As a genetic method chosen the Restriction Fragment Length Polymorphism (RFLP) method and most analysed alleles of milk proteins. Using data of 719 DN A samples of dairy cows, the analysis of Latvian cows’ population was carried out through six SNP of five milk protein genes: C SN1S1 c. – 175 A > G, CSN2 – c. 4451 A > C, CSN3 c. 11625 C > T and c. 11661 A > C, LAA c.15A > G and LGB c. 3106T > C. The results of PCR - RFLP analysis showed, as it was expected, that all genotypes were found in the populations.
Changes in composition and spatial distribution of knowledge-based economy in rural areas of Latvia
(2018) Rivza, B.; Kruzmetra, M.; Sunina, L.
One of the features in the 21st century is growth of knowledge - based economic sector, which is referred as n ew growth theory. New growth theory reflects the attempt to understand the role of knowledge and technology in driving productivity and economic gr owth. In this view, key factors are investments in research and development, education and training and new managerial work structures. The aim of research is to estimate the composition and geographic location of knowledge economy and its perspectives in rural areas of Latvia in post - crisis stage. A special focus was placed on the mentioned processes in territorial units of the regions – municipalities , as the life of residents is influenced not only by national policies, but also by on - going processes in the administrative territories of local governments. The Eurostat classification of industries was used for the analysis of c hanges in composition and spatial distribution of knowledge - based economy. D ata were processed by quantitative and qualitative stat istical analysis, as well as grouping methods. The analysis of the information allows concluding that: municipalities with high and medium - high business is increasing and the business directions with bioeconomic features are the fastest growing ones in ter ms of composition. It must be stated that the economic growth in the rural territories was greatly affected by the quality of local governance and the fact that local community residents’ readiness for active, innovative and inclusive action is strengthene d.
Sunlight potential for microalgae cultivation in the mid-latitude region – the Baltic states
(2018) Stunda-Zujeva, A.; Zuteris, M.; Rugele, K.
Products, e.g. food and feed from microalgae are a promising part of bioeconomy. One of the most investigated and highly demanded microalgae is Spirulina . Light is one of limi ting factors for biomass cultivation by photosynthesis. Sunlight is cheap and climate friendly light source. The aim of this study was to evaluate available sunlight potential in the mid - latitude region - the Baltic states (Europe, 55 – 60 °N ) for microalgae, e.g. Spirulina growth. The data of Climate atlas based on satellites of EUMETSAT and data from an observation station in Riga were analyzed. The latitude and climate (cloudiness) were main parameters affecting the total solar radiation re ceived by Earth’s surface. The sunlight potential in the Baltic states was higher than in most of Europe in similar latitude. Multi - year mean daylight intensity in the Baltic states was slightly less than in Southern France or Bulgaria, (26 klux and 30 klu x , respectively, in summer) where Spirulina is commercially produced. Hourly solar radiation varied a lot in the Baltic states – from 880 W m - 2 to 200 W m - 2 , sunny and overcasted noon of summer day , respectively; average value (8 a.m. – 4p.m.) was 450 W m - 2 . Summer days are longer than 12 h, reaching 18 h in midsummer. The sunlight potential is suitable for microalgae, e.g. Spirulina cultivation in this period. From November till February days are shorter than 10 h and solar radiation is less than 300 W m - 2 e ven in noon of sunny days.
Effects of Monopotassium-phosphate, Nano-calcium fertilizer, Acetyl salicylic acid and Glycinebetaine application on growth and production of tomato (Solanum lycopersicum) crop under salt stress
(2018) Sajyan, T.K.; Shaban, N.; Rizkallah, J.; Sassine, Y.N.
Salinity problem is increasingly affecting tomato production in Lebanon leading to economic losses. The study investigated the potential effects of nano - Calcium (LITHOVIT®), monopotassium - phosphate (MKP: 0 - 52 - 34) fertilizers, Acetyl salicylic aci d (Aspirin) and the osmoregulator glycinebetaine (GB) on salt tolerance of potted determinate tomato (variety Sila) plants in open - field. Salt stress was induced by irrigation solutions of EC = 2, 4, 6, 8 and 10 mS cm - 1 and MKP (2, 3 and 3.5 g L - 1 ), Aspirin (50, 75 and 100 mg L - 1 ), LITHOVIT® (0.5, 0.75 and 1 g L - 1 ) and GB (4.5, 6 and 7.5 g L - 1 ) were applied through foliar application or fertigation. Comparisons between treated and non - treated plants at each salinity level (control) showed that LITHOVI T® decreased the salinity - induced reductions in stem diameter, leaf area and chlorophyll content. Medium concentrations of LITHOVIT® and Aspirin improved stem diameter and all products except Glycinebetaine improved flower number compared to control. Root dry weight and Root Mass Fraction were mostly enhanced in MKP and Aspirin - treated plants. Best improvement in plant yield (76%) was obtained with low concentrations of MKP and LITHOVIT® at EC = 8 mS cm - 1 due to improvement in fruit number rather than fruit weight. Consequently, LITHOVIT® and MKP showed superior effects under salt stress compared to Aspirin and Glycinebtaine.
Performance evaluation of rural areas: the case of Estonian rural municipalities before the administrative reform
(2018) Luik-Lindsaar, Helis; Põldaru, Reet; Põder, Anne; Roots, Jüri; Estonian University of Life Sciences. Institute of Economics and Social Sciences
Estonian municipalities have recently pa ssed an administrative reform that has resulted in the reorganisation of municipal management and decreased the number of municipalities. Unfortunately, no thorough scientific research has been done to find out whether the emerging helps to increase the ef ficiency. The aim of this paper is to estimate the efficiency of Estonian rural municipalities and to identify the factors that influence their efficiency. In this study we use a two stage analysis. In the first stage, we use the DEA Slacks - Based Model’s ( SBM) output - oriented approach. In the second stage, we use the Fractional Regression Model (FRM) to determine relevant exogenous factors that are associated with efficiency. 170 Estonian rural municipalities have been analysed. According to the DEA results , 28% of municipalities (48) are efficient, the average efficiency of municipalities is 0.762. The analysis implies that there are considerable differences between smaller and larger rural municipalities. FRM results revealed that larger share of subsidies characterize inefficient municipalities. The weaker the municipality, the more state support the municipality must receive. A larger share of people with a higher education increases the efficiency, it is related to higher salaries and therefore higher re venue to the municipality. Elderly residents in the population increases the efficiency, however it isn’t sustainable in the long - run because more inputs are needed to offer various public services. The results indicate that the further away a municipality is from the capital, the more inefficient the municipality becomes.
Alarm guard systems for the prevention of damage produced by ungulates in a chestnut grove of Middle Italy
(2018) Conti, L.; Bartolozzi, S.; Iacobelli, S.; Racanelli, V.; Sorbetti Guerri, F.
Wildlife populations, in particular ungulates and carnivores, have had a significant increase in most Italian regions over the last decades and for this reason ecosystems and agricultural and forest productions are threatened by damage produced by wildlife. In order to evaluate effective met hodologies and technologies to mitigate the impact of this phenomenon, innovative protection systems, such as electronic acoustic alarm guard sensors, were tested. These devices are able to randomly produce a significant number of sounds and light projecti ons. At the same time, camera traps were used, as a support instrument to show the presence or absence of wild fauna. Video analysis has provided information on the effectiveness of security systems, on the most suitable methods of installation and managem ent of devices and their ecological impact. Experimental trials were carried out in a chestnut grove located in an Apennine area of the Middle Italy during the harvesting period (autumn). The results obtained have shown that these technologies seem to be particularly suitable for crops that concentrate production in a short time (e.g. vine and chestnut) and in areas not excessively large. Widespread use of devices could mitigate the conflict between public bodies involved in the management of wildlife and farmers.
Comparison of consumption of tractor at three different driving wheels on grass surface
(2018) Abrahám, R.; Majdan, R.; Drlička, R.
The paper deals with possibility of reduction of tractor fuel consumption when working on grass surface, and compares use of two versions of spike devices embedded to the original tyre body. The device was designed at Department Transport and Handling (Slovak University of Agriculture in Nitra). Older as well as newer system proposed in 2017 comprises spikes and it is assembled to common tractor tyre tread pattern with auxiliary grooves cut in. Same device can be set to two positions, allowing to work as 8 - spikes and 16 - spikes system. The spikes are tilted in grooves when moving on paved road. The spikes are ejected out to reduce wh eels slip when operated in field. Remaining eight spikes are tilted in case of 8 - spikes system. Measurements were realised on grass surface. Tractor Mini 070 type was loaded with heavier tractor MT8 - 065 type in tests with 3 different driving wheels, balanc ing the actual weight in all cases. Drawbar pull and fuel consumption were measured in tests, allowing to compute specific drawbar consumption and fuel consumption per hour for three different loads. The results pointed out a fact the tyre slip loss and en ergy consumption of tractor movement increase at the soil humidity 19.45%. It follows from results achieved that use of both 8 - and 16 - spikes wheel device versions reduced fuel consumption when cultivating higher humidity soil, preferable for tillage. Eigh t spikes system with semi - tilted remaining spikes is the most efficient method.
Evaluation of different lighting sources on the growth and chemical composition of lettuce
(2018) Sergejeva, D.; Alsina, I.; Duma, M.; Dubova, L.; Augspole, I.; Erdberga, I.; Berzina, K.
Experiment were carried out in Latvia University of Agriculture in plant growth room. Lettuce Lactuca sativa L. var foliosum cv. ‘Dubacek’ and L . sativa L. cv. ‘Michalina’ were grown under 4 types of lights (luminescence lamps, commercial light emitting diodes (LED) lamps (V - TAC premium series – for plant growing) and two different Lumigrow LED strips - dominant wavelength - blue or red with 14 h ph otoperiod and total photosynthetic active radiation (PAR) 100 μmol m - 2 s - 1 in all variants. Plant weight, length, amount of leaves were measured. Content of chlorophylls, carotenoids, phenols, flavonoids in lettuce was determined three times per vegetation period. In experiments were found that higher lettuce yield was under commercial LED (V - TAC premium series), but these plants contain less soluble sugars, pigments and phenols. Better plant quality was obtained with luminescence lamps. These lettuces have higher sugar, phenols and flavonoids content. Lettuce growth under blue dominate LED (LEDb) was delayed, but these plants contain higher chlorophylls content. The differences in plant growth, response to light and biochemical content b etween cultivars wer e detected.
Influence of soil tillage on oats yield in Central Bohemia Region
(2018) Mašek, J.; Novák, P.
The paper describes results of the field experiment with two technologies of oats crop stand establishment. First technology is conventional technology and second is no - tillage technology. The arti cle describes an experiment which was conducted in years 2013 – 2017. The experiments were located in Nesperská Lhota at Central Bohemia region. Altitude of selected field is 460 m. The experimental field is covered by a light cambi - soil. The differences bet ween the two technologies stand establishment are discussed. Statistical evaluation was performed on both methods in the parameter number of tillers per m 2 and yield. Crop yield is the basic indicator of agricultural production and usually affected by qual ity of soil tillage. One of the parameters affecting the yield is tillage (technology, working tools, depth, turning of soil etc.). Tillage depends mainly on the depth of processing and other quality parameters. An examination of the crop yield is necessar y in terms of sensitivity, depending on agro - technical conditions. Among those can be included processing plant soil nutrition and plant protection. It's always necessary commemorate, in these experiments can't be excluded some parameters like locality or meteorological parameter influences. Field trial was conceived as multi - year experiment with minimal changes of agro - technical conditions. During the experiment, the positive effect of conventional technology on crop yields was found. This difference was r eflected in the number of tillers and in total yield. The measurement shows the beneficial effect of the loosening of soil on the state of the oat crops. The results of experiment show that, the average yield in 5 years observation was 2.11 t ha - 1 for no - t ill technology and 4.22 t ha - 1 for conv entional technology of tillage.
Development of new elements to automatized greenhouses
(2018) Hart, J.; Hartová, V.
Development of new elements to automatized of greenhouses is always needed and be it is to improve the current situation because of the increase effectivity in greenh ouses or their control. Czech University of Life Sciences Prague was to increase efficiency in greenhouses and therefore, devices designed to improve the automation in greenhouses have been designed and patented. The aim was to propose new improvements for automated greenhouses based on demand. This is primarily about solving the problem of lack of daylight and regularly occurring moss on the roof. This research and development are guided primarily because it is a agriculture branch in the stage of expansio n, and it is essential that there is a continuous innovation and research in this field of science. New automatic features or upgrades to existing features in greenhouses, was solved on the basis of the current state of development curent technology. When designet new technologies also help us grants, personal experience with a real installation and cooperation with manufacturers (or with distributors) greenhouses systems. Designs for a light routing system and a system for removing moss from the roof were made.
The potential use of invasive plant species as solid biofuel by using binders
(2018) Zihare, L.; Soloha, R.; Blumberga, D.
The aim of the current research is to find sustainable pellet resources that are not made from forestry, agricultural materials, or food products. Evaluation has been carried out by experimentally determining the biofuel parameters of two invasive plant sp ecies. In comparison to the process of finding a new application, their use in the production of solid biofuel pellets would not require additional investment for the construction of a new pellet production plant. The article’s hypothesis suggests that bio fuel parameters for invasive plant species are sufficient for the production of solid biofuel and that their properties can be improved by binders that are available wor ldwide in the form of residues. The experiment was carried out for two invasive plant s pecies that are widespread in Latvia – Heracleum sosnowskyi Manden and Solidago canadensis L . The binders used include potato peel waste and spent coffee grounds. All of the tests have been carried out according to ISO standards on biofuel testing. Results show that H sosnowskyi is more suitable for solid biofuel than S canadensis as it has a higher calorific value and an ash content that is two times lower – 3wt%. Coffee grounds are a suitable binder b ecause they increase calorific value. The type and amount of binders partly confirms the hypothesis, since both binders reduced the amount of ash in pellets. Further research is needed to carry out pellet durability tests. It is also necessary to carry out an economic analysis in order to evaluate how beneficial it may be to use H sosnowskyi as a solid fuel in existing pellet production plants, thereby avoiding large initial investments and not encouraging the cultiva tion of invasive plant species.

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