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An impact of organic farming on soil quality
Matěchová, Martina ; Jakšík, Ondřej (advisor) ; Janků, Jaroslava (referee)
This work focuses on the system of organic agriculture and its impact on soil quality. It compares organic farming system with conventional. Both these systems are briefly described. There is also a list of soil quality indicators used for the soil quality is evaluation. The results of scientific studies, which dealt with different farming systems and their effects on soil properties, were discussed and evaluated.
Quality and fertile soil is crucial for production systems, however to define what means quality soil is very difficult. Therefore the number of quality indicators were established. The indicators can be grouped by their nature of soil properties they assess, such as physical, chemical and biological. Different techniques are adopted for soil quality evaluation.
Soil quality is affected by a lot of different factors. Anthropogenic activities are often considered as one of the most influential factor. The loss of soil fertility as well as other physical, chemical or biological deterioration of soil properties is called soil degradation.
The results of this study shown that careful tillage in organic farming could have positive effect or no effect on the biological and physical properties of soils. For some experiments there was an increased amount of soil organisms.
In the most experiments, application of organic fertilizers caused increase of organic matter and other essential nutrients. We conclude that under certain conditions with respect for the principles of organic farming the soil quality can be preserved or even improved, but in a longer timeframe.
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Influence of former landscape elements on soil properties
Matějovský, Jiří ; Zádorová, Tereza (advisor) ; Luděk, Luděk (referee)
Hedgerows are elements in landscape, creating a landscape structure and influencing soil properties. This thesis is focused on the assessment of impact of the former landscape elements on current soil properties. Study area is located in the Central Bohemian Region, in the district of Pribram. Study plot area is 33 ha and is currently managed as a single large unit without any landscape elements. Assessment of the degree of impact on soil properties was mainly focused on soil depth, stratigraphic profile and organic carbon content. Sampling was carried out perpendicularly to the four selected hedgerows. The deepest soils, as well as the largest percentage of organic carbon were observed in areas of the original occurrence of hedgerows. Places above the hedgerows did not show significantly better soil properties, while at the locations below the hedgerows were identified deeper soils and increased organic carbon content. These findings confirmed the importance of hedgerows and their ability to influence soil properties.
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Influence of common eland (Taurotragus oryx) meat composition on its further technological processing
Kolbábek, Petr ; Lukešová, Daniela (advisor)
This dissertation has been proposed as a part of long-time wide research conducted on farmed elands (Taurotragus oryx) at university farm at Lány. This thesis is planned to be closely connected with the study of influence of the nutrition and diet to the growth and meat composition and quality. Eland meat is traditionally considered as tasty and nutritionally valuable, but in fact the knowledge on the eland meat composition and technological processing potential is limited. The research will be focused on the analyses of physical and chemical properties of meat with emphasis on the influence of the diet and age of animals on the meat. Next part of the work will be to experimentally produce meat products (e.g. pâté, fermented salami) and evaluate theirs physical, chemical and organoleptic properties. The most of the analysis are planned in cooperation with Department of agriculture products quality on Faculty of Agrobiology, Food and Natural Resources.
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Factors affecting the properties of glued joints for glues used in the wood industry
Boška, Pavel ; Böhm, Martin (advisor)
Dissertation focuses on the influence of selected factors on the properties of the bond glued by acetate polyvinyl adhesives. Factors such temperature and moisture content of the environment, the pressing pressure and cyclic stress. Despite the same type of adhesive, the properties may vary for different producers of adhesives and according to which the product is not intended. Influence will be compared to the test samples of dried beech timber with regard to shear bond strength. They will be compared properties of adhesives from different manufacturers and different destination. Test samples and test progress carried out in accordance with current standards, or largely based on. This research should help users streamline the process of adhesive bonding and reduce the production costs of the bond.
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Influence of texture of briquettes from biomass to their mechanical properties
Černá, Iva ; Pecen, Josef (advisor) ; Jan, Jan (referee)
With the rising amount of AD technology utilizers, the issue how to storage, such liquid
material, which digestate is. In recent time, there are some other ways to utilize it, except
fertilizing with liquor, liquid part of digestate. Digestate can be dried and pressed into
briquette or pelleted form. In briquette form is important to understand relations between
properties of individual components because one property can influence another one, which
constituting texture of the material and its reprocessing into the final form of the product.
Thus this study was conducted, to find and/or quantify the relation between the texture of
biomass briquettes and their durability and strength of shape during manipulation, storage
and use. Basic hypothesis of this work is based on open presumption that briquette texture is
dependent on many parameters. Some of those parameters were tested. Namely, composition
of matter, physical properties of digestate briquettes, durability and hardness, size analysis
and other. Digestate has approved as good material for compression with high content of
nutrients. The rate of abrasion varied 7-12% at the beginning decreasing to 3-5%. Shore
testing showed results predicating relation between particle size and hardness. Sieve and
image analysis then showed range of particles ranging size 0.01 mm from 99.5% and 10 mm
from 99.7%, most of them with needle-like shapes. This study suggested the method that
allows analysing particle size distribution in sample and describes other briquette properties,
which can be useful for next research and commercial purposes.
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Mophological and molecular diversity of a tropical tree species Guazuma crinita in the Peruvian Amazon
Tuisima Coral, Lady Laura ; Lojka, Bohdan (advisor) ; Helena, Helena (referee)
Fast growing tree species Guazuma crinita (Malvaceae) was selected as a priority species for domestication in the Peruvian Amazon due its important contribution to the livelihood of local farmers. Its domestication process is still in an early age as for many tropical tree species little is known about its genetic variability and we dont know anything about the impact of domestication on its genetic resources. The main objective of this research was to assess the genetic variability of G. crinita within and among populations in the Peruvian Amazon by the use of morphological (wood physical traits) and molecular (ISSR and AFLP) markers.
Wood physical properties among six G. crinita provenances were evaluated. Wood samples were drilled from the base middle and top of the stem of 12 randomly selected eight-years-old trees for determination of wood measurement. Pearson correlations between physical properties were also determined. All wood physical properties except green density differed significantly among provenances. We also found statistically significant variation due to stem level position. The moderately dense wood and the coefficient of anisotropy (1.6) suggested that G. crinita has stable wood; they represent important advantages in terms of costs for transport and transformation process. The results suggested potential to select provenances with desirable wood properties for further breeding and domestication. Due to the variation found even in limited tree samples it is recommended further analysis with more extensive number of samples from different provenances and planting zones.
This research presents the first assessment of genetic variability based on inter-simple sequence repeat (ISSR) markers for 44 G. crinita genotypes from a clonal garden multiplication established in the Peruvian Amazon Research Institute (IIAP) in Ucayali region. Ten ISSR primers amplified a total of 65 bands of which 61 were polymorphic (93.8%). The range of DNA amplification varied from 260 to 2200 bp. Among the provenances overall genetic differentiation (Gst) was 0.03 indicating 97% of genetic diversity within provenances. Gene flow (Nm) was 12.9 alleles per generation. Cluster analysis was not related with geographic origin suggesting a common gene pool which was supported by calculation of weak positive correlation was found between genetic and geographic distance.
With the use of AFLP markers an insight on how domestication process does impact G. crinita genetic resources is also reported on this research work. I was able to generate fingerprint for 58 leaf samples representing eight provenances and three population types, 19 from a natural regenerated population 15 cultivated in home garden nursery and 24 from a collection of genotypes considered as semi-domesticated population. Seven selective AFLP primer combinations were used. A total of 171 fragments were amplified with 99.42% of polymorphism at species level. Each type of population generated fragments with 72.51% 49.12% and 54.39% of polymorphic fragments respectively. Neis genetic diversity and Shannon index information were found to be higher in the population of natural regeneration compared to overall semi-domesticated population (He = 0.10 and 0.9; I = 0.19 and 0.16 respectively). The analysis of molecular variation (AMOVA) showed higher variation within provenances rather than among (84% and 4% respectively). UPGMA clusters analysis and PCoA did not showed correspondence between genetic and geographic distance in addition their correlation was not significant. There was a significant genetic differentiation among types of population suggesting slight genetic bottleneck in semi-domesticated populations yet with relatively high levels of genetic variation.
In situ conservation for populations with high levels of genetic diversity was recommended. In addition proper management of natural regeneration and ex situ genotype collections might be a good conservation strategy to maintain G. crinita genetic resources.
The use of morphological (wood physical traits) and molecular markers were successful to reveal genetic variability of G. crinita and they could be used for other tropical tree species. For further researches it is emphasis to extent the number of samples and geographic scale.
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Assessment of in vitro antioxidant properties of medicinal and edible plant extracts
Tauchen, Jan ; Kokoška, Ladislav (advisor) ; Jaromír , Jaromír (referee)
Identification and characterization of plant-based products with antioxidant and anti-proliferative effects has received much interest over the past few years as possible therapeutic mean for treatment of diseases likely to be associated to oxidative stress (such as atherosclerosis, diabetes, and cancer). This study provides characterization of in vitro antioxidant and/or anti-proliferative potential and phytochemical profile of (i) 39 wine samples of underutilized Georgian grapevine cultivars, (ii) extracts of 22 samples of medicinal plants from Ethiopia and (iii) 23 samples of edible and medicinal plants from Peruvian Amazon. For this purpose, 2,2-diphenyl-1-picrylhydrazyl radical assay (DPPH), oxygen radical absorbance capacity (ORAC) assay, total phenolic content (TPC), and cell viability assay based on metabolization of tetrazolium bromide (MTT) to formazan, together with methods based on high performance liquid chromatography (HPLC-ultra violet/visible spectrometry and HPLC-tandem mass spectrometry) were used. Georgian red wines (particularly Saperavi cultivars) exhibited higher antioxidant capacity (average DPPH and ORAC values at 5.1 and = 10.6 g TE/L wine, respectively) in comparison to Central and West European cultivars [Pinot Noir (DPPH = 3.1 and ORAC = 9.4 g TE/L wine), Cabernet Sauvignon (DPPH = 3.0 and ORAC = 7.3 g TE/L wine) and Cabernet Moravia (DPPH = 2.0 and ORAC = 8.5 g TE/L wine)]. Georgian wines contained significantly greater concentrations of quercetin (between 14.44 and 1.07 ug/mL), kaempferol (between 1.68 and 0.03 ug/mL) and syringic acid (between 12.59 and 4.72 ug/mL), whereas possessed lower quantities of resveratrol (between 5.11 and 0.32 ug/mL) in comparison to Central and West European wines. Amongst edible and medicinal plants from Ethiopia and Peruvian Amazon, only Dodonaea angustifolia (IC50 for DPPH = 22.2 ug/mL, ORAC = 767.6 ug TE/mg extract; IC50 for Hep-G2 = 120.0 ug/mL), Rumex nepalensis (IC50 for DPPH = 5.7 ug/mL, ORAC = 1061.4 ug TE/mg extract; IC50 for Hep-G2 = 50.5 ug/mL), Inga edulis (DPPH and ORAC = 337.0 and 795.7 ug TE/mg extract; IC50 for Hep-G2 and HT-29 = 36.3 and 57.9 ug/mL) and Oenocarpus bataua (DPPH and ORAC = 903.8 and 1024.4 ug TE/mg extract; IC50 for Hep-G2 and HT-29 = 102.6 and 38.8 ug/mL) have demonstrated combinatory antioxidant/anti-proliferative efficacy. Selective anti-proliferative activity was observed for Verbascum sinaiticum (IC50 for Hep-G2 = 80.6 ug/mL) and Annona montana (IC50 for Hep-G2 and HT-29 = 2.7 and 9.0 ug/mL, respectively). Above-mentioned plant material showed only weak or non-toxic effects towards normal cell line. Despite the fact that extracts of Jasminum abyssinicum (IC50 for DPPH = 26.3 ug/mL, ORAC = 1023.7 ug TE/mg extract), Rumex nepalensis (IC50 for DPPH = 5.7 ug/mL, ORAC = 1061.4 ug TE/mg extract), Mauritia flexuosa (DPPH and ORAC = 1062.9 and 645.9 ug TE/mg extract), Myrciaria dubia (DPPH and ORAC = 641.9 and 642.6 ug TE/mg extract) and Theobroma grandiflorum (DPPH and ORAC = 714.8 and 821.9 ug TE/mg extract) have exhibited considerable antioxidant effect, these species were found to possess moderate to low anti-proliferative potential or have shown to be toxic to normal cells line. In all cases it was detected that phenolic compounds content correlated strongly with antioxidant activity, however weakly with anti-proliferative effect. Results suggest above-mentioned species as prospective materials for further development of novel plant-based agents effective against oxidative stress related diseases. However, it is necessary to perform further research which would be focused on detailed characterization of their chemical composition, pharmacological effects and toxicological safety, in order to verify their possible practical use.
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Kinematics and elastokinematics of independent multi-link suspension of axle using flexible supporting elements
Vrána, Tomáš ; Kovanda, Jan (advisor) ; Ladislav, Ladislav (referee)
This thesis deals with elasto-kinematic properties of multi-link rear suspension
system, based on simulations. The creation of computational model and simulation of
elastokinematics are based on specialized modules of the HyperWorks software. The
thesis idea is to create new models and improve their properties.
The chapter introduction presents and discusses the current knowledge state in the
issue of elasto-kinematic characteristics of the vehicle suspension. Previously published
works are presented in this section. The following section defines basic terms, features
and design elements concerning the topic vehicle suspension and vehicle axle, which
can help readers to orientate in this field.
The first part of the thesis is focused on the collection of high-quality input data to
create the MBS computational model based on the real suspension components. The
determination of kinematic suspension points, experimental measurements of inertia
moments of supporting elements of the suspension and measurements of deformation
characteristics of rubber-metal bushings are presented in the thesis. There are also
measuring characteristics of force elements such as springs or shock absorbers. Then the
proposed method of measuring elasto-kinematic characteristics of the suspension using
testing machine for model validation is also introduced.
The second and main part is devoted to creating a new MBS simulation models of
multi-link rear suspension using HyperWorks system. The suspension model is
improved by successive steps, from kinematic model, through model with flexibility of
the bushings, to the complex model in which the flexible properties of all supporting
elements are reflected. The properties of the used models are described together with
arising calculation problems. The results discuss the impact of elements flexibility and
individual structural alternatives on elasto-kinematic characteristics of the suspension
system.
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Use of composts and vermicomposts and their extracts together with bioffectors for growing of plants.
Bouček, Jiří ; Tlustoš, Pavel (advisor)
The aim of this project will be to determine the influence of conditions during composting and vermicomposting of biodegradable waste of organic matter on physical-chemical properties of compost and vermicompost extracts. From this point of view mainly the content of basic nutrients and humin substances will be monitored and also the possible content of risk elements. In the same purpose the presence of different types of microorganisms in these extracts will be investigated and the enzyme activity of microorganisms in their extracts will be also determined. The extracts will be simultaneously prepared under aerobic and unaerobic conditions in different portion among the organic matter and its leachate and each sample variants will be compared to above conditions. The real effect of extracts applied on grown plants or into a soil including the fungicide effect of sample extracts during pot experiments will be reported. The effect of extracts will be also compared with commercial bioeffectors.
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Factors influencing seed germination, emergence and mortality in soil seed bank of Bromus sterilis L.
Žďárková, Veronika ; Soukup, Josef (advisor)
Bromus sterilis L. (barren brome) spreads rapidly in many European regions. In the Czech Republic, its importance has increased dramatically over the past 10 years. Barren brome is reported as a problem weed in winter crops such as winter wheat, winter barley and oil seed rape, in vineyards and in other cultivated places. Barren brome has been becoming troublesome weed of winter cereals mainly in reduced soil tillage systems. The factors, that are important for its spreading and adaptability under different environmental conditions, are dormancy and germination. Optimal timing for seed germination varies with respect to natural conditions and it is determining for plant development. These traits are adapted to different conditions and habitats; therefore the dormancy and germination response patterns to those conditions vary significantly. Recently there are not many information available on germination behaviour, therefore this study was focused on seeds of barren brome and its characteristics, which were collected in different regions of the Czech Republic. Seeds were investigated under different temperatures, light regimes and water stress in a wide range of conditions. The following characteristics of seeds were studied the dormancy, the dynamics of germination, the temperature optimum, the age of seeds and dynamics of emergence from different depths and persistence in the soil profile under field conditions. Dormancy and germination are influenced by external conditions. The dormancy of seeds barren brome is very short or missing. The germination is influenced by light; the seeds germinated better under darkness than under light regime. The primary dormancy of B. sterilis was short and the seeds needed only three weeks for after-ripening. The seeds of B. sterilis showed broad ecological valence to hydrothermal factors germinating in the wide range of 3 to 35 °C. The temperature optimum is 5-23°C. The germination was only slightly influenced in an environment with low water potential. Germination was limited under water stress only at lower temperatures under 10°C. The response to light at various temperatures showed that seeds germinated better in darkness in all temperatures regimes, than in alternating light regime, especially at lower temperatures. The emergence declined significantly with burial depth (under 40 mm). The seeds were not able to survive in the soil seed bank for a longer time and fall seeds lost viability after 1 year burial in soil profile. These results may be of value for development of predictive models and understanding period when weed control may be most feasible.
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