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Dopady přehnojení dusíkem na biologickou aktivitu půdy hnojené biologickým odpadem
Slezák, Marek
Findings that occurred during the practical part of the diploma thesis confirmed the working hypothesis that the application of biodegradable components to the soil has a positive influence on the activity of soil microorganisms. The greatest increase in microbial activity occurred with the use of manure, but in this application there was a greater degree of leaching of mineral nitrogen from the soil. Application of manure on arable land appears to be the best and most economical way to promote microbial acti-vity in soil.
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Vliv některých organických hnojiv a minerálního hnojiva na vybrané půdní parametry =: Influence of some organic fertilizers and mineral fertilizer on selected soil parameters /
Šimečková, Jana
The search for new sources of electrical energy has influenced among others agricultural practice too. The fermentation process of biogas plants requires the adjustment of crop rotation to ensure sufficient input material throughout the year in the same composition, e.g. corn silage. The by-product, digestate, is applied to agricultural land as an organic fertilizer. However, the effect of its long-term application on soil properties is not explained. In a field trial in Vatín (soil type cambisol modal), the effect of application of digestate, mineral fertilizer and farmyard manure (150 kg.ha-1 N dose) on physical (bulk density, porosity and pore distribution, water holding capacity, minimal air capacity, structure and soil temperature) and hydrophysical (hydraulic conductivity, infiltration, moisture) soil properties was compared in the vegetation cover of corn monoculture, Norfolk crop rotation and permanent grassland. The three-year results indicate that the application of organic fertilizers (i.e. farmyard manure and digestate) has positively affected the physical condition of the soil, particularly soil structure and infiltration. Soil temperature amplitude was more balanced with digestate than with mineral fertilizer. The dynamics of the development of individual monitored soil properties were different concerning the type of vegetation cover.
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Vyhodnocení systému Isaria Crop Sensor v podmínkách konkrétního podniku
VONDRÁČEK, Jan
The diplom thesis presents some elements of precision agriculture and their possible use. The thesis focuses on using the elements of precision farming in practice. In the practical part, the work is focused on the practical use of the sensor system Isaria Crop sensor N in the conditions of the agricultural company Kooprodukt Lišov a.s.
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Vyhodnocení vlivu hnojiv řady Silvamix, vápnitého dolomitu a organominerálního stimulačního přípravku na podporu odrůstání smrku ztepilého (Picea abiesL./ Karsten)
Češek, Tomáš
The final work discusses the influence of the applied treatment of the series Sylvamix (Sylvamix A + stimulator, Sylvamix F + stimulator, Sylvamix R + stimulator, Sylvamix R), dolomitic limestone and organo-stimulatory product Vermaktiv, with regard to the nutrition of spruce (Picea abies /L./ Karsten). The research was conducted in forest nursery named Dykova and forest nursery named Budišov. In each forest nursery were further divided surfaces into individual fertiliser allotments. Assessment of the influence of the applied preparations was evaluated after two years from application. The main objective of this work was to evaluate the effect of individual fertiliser preparation. The analyses carried out it has been observed that the application fertiliser product has a positive effect on nutrition, faster growth and mightier root system of spruce. Top results were obtained product Sylvamix F + stimulator and showed also a positive effect of Sylvamix R + stimulator. The effect of each fertilizer varies depending on ecological site conditions habitat.
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Social learning among Ghanaian cocoa farmers: Choosing the optimal amounts of inputs
Švenka, David ; Janský, Petr (advisor) ; Havránek, Tomáš (referee)
In this thesis I inspect learning about adoption of technologies among cocoa farmers in Ghana, which are represented by non-labor inputs, particularly by fertilizer and hybrid seeds. Earlier research focused mainly on learning about returns associated with adoption of such innovative inputs. However, it is not clear whether the adopters learn about these returns or rather about what are the optimal amounts of these inputs. Therefore the focus of this thesis is to examine how do the farmers choose and learn about optimal amounts of inputs. Cocoa farming is very labor intensive, and thus this thesis concentrates on learning about both non-labor and labor inputs, which are closely connected. Similar research carried out in India suggests that heterogeneous returns among farmers might cause that the farmers rely rather on their own considerations than on observation of behavior of their village neighbors, i.e. social learning. The heterogeneous returns are also present among the Ghanaian cocoa farmers, which suggest that these farmers should similarly prefer individual learning over the social one. Using a model developed for estimation of the prevailing type of learning about the optimal amount of inputs, I show that the farmers do tend to prefer individual learning in case of the non-labor inputs but rather...
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Fermentation remainder treatment in a biogas plant
Budín, Oto ; Touš, Michal (referee) ; Vondra, Marek (advisor)
This diploma thesis deals with dewatering technologies of fermentation residues from biogas plants and aims to design an integration of selected technology into the biogas plant. Fermentation residues (or digestate), which are a by-product of anaerobic biomass fermentation in biogas plants, contain a certain amount of nutrients and are usually used as agricultural fertilizers. However, the high-water content in digestate and the associated low nutrient concentration increase the cost of its storage and transport. Dewatering of fermented material could help reduce these costs. The main part of this work included the design of an integration of the selected dewatering technology into the biogas plant – its placement in a process, an addition of necessary appliances, the influence on material and energy flows. In this case, the fermentation residues are processed in two phases. First, a separation of the solid and the liquid fraction by a screw press. The second step is to thicken the liquid digestate by evaporation in a multistage evaporator. Evaluation of the design of a dewatering technology, including its impact on the economy of the biogas plant, is also part of the diploma thesis.
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Ghana cocoa farmers' survey: chocolate economics
Svatoň, Michal ; Janský, Petr (advisor) ; Průša, Jan (referee)
In this thesis I evaluate long-term productive and economic impacts of the Cocoa Abrabopa Association, a private sector initiative providing fertilizer and other agrochemicals to Ghanaian cocoa farmers on credit with a joint lia- bility. Both the productive and economic returns of the program are expected to be higher in the latter years of sustained membership in the program due to the accumulation of nutrients in the soil and the possibility of the exten- sion of the size of the loan provided by the program. Earlier work focused only on the estimation of the effect of adoption of agricultural technology but did not allow to examine possible difference in returns of a longer par- ticipation. This thesis contributes by evaluating the impacts in the 1st, the 2nd and the 3rd year of the CAA membership and their comparison. By constructing and estimating a model for the impacts of longer participation I confirm the hypothesis of higher economic returns during the 2nd and the 3rd year of participation in the CAA program. The evidence which would confirm the hypothesis of higher agronomic returns has not been found in the case of CAA. 1
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Equipment for Thickening Waste Water from Biogas Plants
Vondra, Marek ; Bébar, Ladislav (referee) ; Hoffman,, Pavel (referee) ; Stehlík, Petr (advisor)
This dissertation thesis deals with the development of technology which could tackle two major issues related to biogas plants. These issues concern the insufficient use of waste heat from biogas combustion and its subsequent processing. It also concerns the use of the fermentation residues which are formed in large quantities and whose use is restricted by law. Based on a literary search of separation methods, a vacuum evaporator was selected as the most suitable technology. Its advantages include its simple construction, operational reliability and robustness, low costs of thickening medium pre-treatment, potential for a quick commercial application and, especially, the chance to use a low-potential waste heat. A primary purpose of this technological unit is the reduction in the volume of fermentation residues. Other benefits include the efficient use of waste heat from a biogas plant, which would otherwise be wasted. Evaporators with a low consumption of electrical energy (which is a main product of a biogas plant) seem to be the best option for applications in the biogas plants. Three of these technologies were subjected to a more thorough analysis, which included the development of computational models and their quantification for conditions in a sample biogas plant. A one-stage evaporator with a forced circulation (680 – 712 kWhth/m3, 25.9 – 30.5 kWhel/m3) was evaluated as the least suitable option in terms of energy demands. The energy intensity of a three-stage evaporator with a falling film (241 – 319 kWhth/m3, 12.0 – 23.6 kWhel/m3) and a nine-stage flash evaporator (236 – 268 kWhth/m3, 13.6 – 18.4 kWhel/m3) is significantly lower. A multi-stage flash evaporator (MSF) was then chosen for development and will form the central focus of this thesis. The reasons for the choice are as follows: the low requirements on the heat transfer surface, good operational experience in the field of desalination, its simple construction, modularity and evaporation outside the heat transfer surface. A thorough technical-economic evaluation was also performed on the integration of the evaporator into the biogas plant. The main part of the work included the experimental development of a MSF evaporator prototype. The main objective of this development was to achieve a stable flow rate of the thickening liquid digestate fraction and the continuous formation of the distillate. This was not an easy objective to achieve, especially due to the properties of the liquid digestate, which has a non-newtonian characteristic and increased density and viscosity compared to water. The tendency of the liquid digestate to form foam was also the subject of analysis. The development of the evaporator and first successful operational test are described in the thesis in detail. This required the use of an anti-foaming product. A fully-developed prototype of the MSF evaporator allowed us to achieve continuous operation with a distillate production, reaching from 5 to 10 kg/h at a liquid digestate flow rate of 0.4–0.5 m3/h. The main drawback of this technology is the pollution of the distillate with ammonia nitrogen, and it is for this reason that the basic procedures of its subsequent elimination was selected for further analysis.
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Návrh antikorozní ochrany u strojů pro aplikaci hnojiv v zemědělství
Mareček, Tomáš
The diploma thesis is focused on proposal corrison protection on machines for application of fertilizers in agriculture. The theoretical part describes the distribution of machines for fertilizer application, issue and species of corrosion. The next section discusses the electrochemical corrosion, its principles and distribution. The final section is an experiment that has analyzed the possibility of using five kinds of corrosion protection evaluation of corrosion tests in laboratory.
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Humic substances as transport medium for plant nutrition
Vlková, Markéta ; Solná, Irena (referee) ; Klučáková, Martina (advisor)
This bachelor thesis treats about humic matters and their application in agriculture by means of hydrogels transport medium. It studies progressive releasing of substances, which could be used as more common nutrition for plants, prepared from superabsorbent polymers. Research was implemented in collaboration with industrial partners. The substances are synthetically made of sodium Lignohumate and mixture of industrial fertilizer called NPK. Released substances were characterized by using some methods. First, there were measured qualities, which didn’t specify released compounds, like swelling, conductivity, pH and absorption of hydrogels with different wavelengths. More details came with methods ICP-OES and ion chromatography. Hydrogels which contained both mixtures of matters written up, were studied in water solution for 5 weeks and every week all characterization were measured. From the results we can see that both of the mixtures decrease ability of hydrogel’s swelling, mainly NPK. Measuring of absorption showed that the most of the substances released from sodium Lignohumate were from hydrogels without NPK. By other measuring, we noticed realizing of potassium and phosphorus elements. The most of them were from hydrogels containing NPK. By measuring ion chromatography, we found chloride, phosphoric, sulfuric and nitric ions in solution.
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