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Exceptions to the positive relationship between species diversity and environmental heterogeneity
Srpová, Tereza ; Hořák, David (advisor) ; Divíšek, Jan (referee)
The positive relationship between environmental heterogeneity and species richness has been taken for granted for many years. However, recent studies have revealed possible alternatives to this positive relationship, such as negative or unimodal relationship. There are many possible explanations for these alternative relationships. Increasing spatial heterogeneity of a biotope of a given size inevitably leads to reduction in the effective area available to the organisms inhabiting it. At the same time, increased environmental heterogeneity can lead to fragmentation and isolation of biotope patches, which can have negative consequences for the species richness of the community. Inadequate methodology may be one of the reasons why these alternative relationships have only been discovered in the recent years. Correct information on the relationship between environmental heterogeneity and species richness is essential for decisions on biodiversity conservation. For this reason, it is necessary to discover such alternative relationships in specific ecosystems, which we aim to protect, and to always take them into account, even if they are less common.
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Aesthetical value of environmental heterogeneity
Bufka, Ondřej ; Hořák, David (advisor) ; Janečková Molnárová, Kristina (referee)
Throughout their lives, people are in constant contact with the natural environments that surrounds them. The aesthetic value of this environment has a great infuence on man's relationship with it. There is also a connection between the aesthetic value of the environment and it's heterogeneity. Environmental heterogeneity includes physical, topographical and also biodiversity of the environment. It is also an important factor influencing it's ecological and aesthetic value. High levels of heterogeneity in a landscape can have a positive impact on biodiversity, resistance against disturbances and also on people's aesthetic preferences. Positive effects resulting from people's contact with visually attractive landscapes can further motivate them to protect and conserve nature and even improve their mental health. The aesthetic value of the environmental heterogeneity therefore has a great, but not yet fully exploited, potential for nature conservation and landscape management.
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Využití smart farming technologií při hospodaření na zemědělské půdě
Kovaříková, Jana
The bachelor thesis deals with the basic theoretical description of smart farming technologies or precision farming methods in agricultural land management. Precision farming is a trend that has been developing since the early 1990s. One of the elements of precision farming is locally targeted farming that works with soil heterogeneity and tillage using new technologies. Optimizing soil inputs (mineral fertilizers, pesticides, etc.) and applying them according to the current plant requirements is one of the goals of smart farming. Through precision farming agronomic practices, we can increase the efficiency of crop production, reduce the amount of mineral fertilizer inputs and improve both economic and environmental status. The aim of the presented work was to evaluate the variable application of essential nutrients (P and K) on selected plots managed in a conventional way using PREFARM. The experiment itself was carried out in the agricultural company AGROSUMAK a.s., The practical part includes a comparison of lump and variable application of potassium salt (K2O source) and triple superphosphate (P2O5 source) on three experimental plots. Data on plot heterogeneity were provided by AGROSUMAK a.s., which uses the PREFARM system. In the conclusion of the present work, the results are discussed and compared from economic, environmental and agronomic points of view.
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Mapování půdních vlastností a ekonomické vyhodnocení variabilní aplikace zásobního hnojení
Blaha, Jiří
This master thesis is focused on the mapping of soil heterogenity by soil sampling. The experimental part of the work was realized on the arable land managed by agricultural holding Rostěnice a.s. within the research project NAZV QK21010247. Totally 1018 soil samples were taken during summer 2022 in irregular sampling grid in the area of 1 838 ha. After laboratory analysis of soil samples for estimation of main agri-chemical soil properties, a map of phosphorus was computed by using spatial interpolation techniques. The results has shown the high spatial variability within the observed fields. La-ter six variants of nutrient dose recommendation were compared. There were two uni-form rates (UNI_M3 and UNI_BK10) and four variable rates (VRA_M3, VRA_BK10, VRY_M3 and VRY_BK10). The economical evaluation prooved only small differences in total costs of phosporus fertilizers among the variants. However, the optimization of nutrient distribution within the fields based on the spatial heterogeneity and yield level is the main advantage of variable rate application.
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Mapování heterogenity stanoviště pomocí metod a technologií používaných v systému precizního zemědělství
Šmoldas, Radomír
The master thesis "Mapping habitat heterogeneity using methods and technologies used in the system of precision agriculture" deals with the heterogeneity of fields in the selected farm Tršická zeměděská a.s. The thesis begins with literature review which has knowledge critical for practical part of the thesis. At the beginning precision farming and its goals are briefly described. Furthermore, the literature review deals with the issue of mapping the heterogeneity of fields and how to monitor it. The following section discusses global navigation systems. Specifically, what versions do we have and their contribution to precision agriculture. Literature reviews ends on the chapters of remote sensing and geographic information systems. The thesis continues with the practical part, which deals with the heterogeneity of selected fields in the farm Tršická zemědělská a. s. First, however, the natural and production conditions and the equipment of the farm are described. After that the supply of macroelements and pH was monitored on the selected fields, and maps of the supply were created in the ArcGIS program. Subsequently, these maps were compared with the results from 2021. Finally, maps of the recommended rate of variable fertilization of the fields were created for the model crop and desired yield.
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Influence of environment in host cells on heterogeneity of virulence factors expression in Salmonella
Mathéová, Paulína ; Černý, Ondřej (advisor) ; Konopásek, Ivo (referee)
Bacteria of the genus Salmonella are one of the most important human pathogens. Salmonella expresses several virulence factors, including the type three secretion system encoded on the Salmonella pathogenicity island 2 (SPI-2 T3SS) and its effector proteins. SPI- 2 T3SS effector proteins allow the bacteria to colonize host cells, persist there and use them as a Trojan horse for migration throughout the host organism. Although the function of the SPI- 2 T3SS is essential for the bacterial population during systemic infection, some bacteria do not express this virulence factor and benefit from its expression by other members of the population. Similar heterogeneity in expression of other virulence factors has been shown to be crucial for their function. This work focuses on the heterogeneity of expression of selected SPI-2 T3SS effector proteins under the influence of host factors (pH, ROS, RNS) affecting bacteria during intracellular infection of macrophages. Using a fluorescent reporter system suitable for flow cytometry the expression of selected effector proteins was detected at the level of individual bacteria. The obtained data show, that individual bacteria respond differently to the decrease in pH in their vicinity. Part of the bacterial population starts to express the studied effector...
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Heterogeneity of antigen-presenting cells in the thymus and its relevance for the establishment of central tolerance
Sýkora, Vojtěch ; Filipp, Dominik (advisor) ; Černý, Jan (referee)
The crucial function of the thymus is the establishment of central tolerance. In this process, developing T-cells are tested for their self-reactivity, since self-reactive T-cells might cause the autoimmunity if they would escape from the thymus to the periphery. Many thymic antigen-presenting cells are essential for establishment of central tolerance. Their role is to present self-antigens to the developing T-cells. Such presentation is capable to reveal the self-reactive potential of T-cells which can be then directly removed or deviated into suppressive T-regulatory cells. In the last several years, a high level of heterogeneity has been described among the thymic antigen-presenting cells and the molecular mechanisms that govern their functions towards enforcement of tolerance began to be uncovered. This thesis summarises recent knowledge in the field of heterogeneity of the thymic antigen-presenting cells and its relevance for establishment of the central tolerance, with the major focus on conventional dendritic cells and post-AIRE medullary thymic epithelial cells. This thesis also outlines recent advances in understanding of functional mechanisms and regulations of maturation of the antigen-presenting cells.
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