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The theoretical part of this doctoral thesis provides a comprehensive overview on the topic of preparation and subsequent utilization of magnetic derivatives of biological materials for xenobiotic separation from water. Main attention is paid to magnetic modification of waste materials and by-products originating from agricultural and food industry, which represent widely available and low-cost materials, and also to magnetic modification of microbial cells. In addition to the description of magnetic particle preparation and individual developed techniques of magnetic modification, a brief characterization of selected pollutants and a detailed table overview on utilization of magnetically responsive biomaterials for biosorption of organic dyes, heavy metals, pharmaceutical and personal care products together with ubiquitous industrial endocrine disruptors and also of crude oil derivatives is presented. Experimental part of this thesis is focused on the preparation and optimization of new types of magnetic materials. Emphasis is placed on the employment of simple, fast and simultaneously low-cost magnetic modification techniques (e.g., postmagnetization using microwave-synthesized magnetic iron oxides or one-step modification by magnetic fluids). Selected plant materials (barley and rye straw) were chemically modified to significantly (up to five-times) increase the maximum adsorption capacities for tested dyes. All prepared biomaterials exhibited a great magnetic response and simultaneously relatively high adsorption capacity for selected xenobiotics under experimental conditions used. Factors substantially affecting adsorption process, such as pH, initial concentration, incubation time or temperature were also studied. Adsorption equilibrium data were assessed using Langmuir, Freundlich or Sips isotherm models. Experimental data from time dependence study were analyzed by chosen kinetic models, namely the pseudo-first-order and pseudo-second-order ones and by intraparticle diffusion model. Thermodynamic parameters (Gibbs free energy, enthalpy and entropy) describing the nature of adsorption were also included in study.

Microbial diversity plays an important role in the decomposition of soil organic matter. However, the drivers of this dependence still remain unclear. The work is based on long-term monitoring of soils of different successional stages of different diversity. Soil sampling was conducted on two dumps after brown coal mining in the Sokolov. Soils were X ray sterilized and inoculated by inoculum from both soils in two inoculation density which create gradient of microbial diversity. Then microbial respiration was measured in either supplied or not supplied by litter of Calamagrostis epigejos. Results showed a strong positive correlation between the microbial diversity and decomposition of organic matter if the microbial community is limited by available carbon. If there isn't carbon limit available, the decomposition rate is controlled by the amount of microbial biomass. Results demonstrated positive correlation between the rate of decomposition and the amount of fungal biomass. The soils with the addition of leaf litter showed priming effect in the initial stage of decomposition. In the control samples without addition of litter priming effect wasn't observed. Increasing humidity led to increase of decomposition rate. We can conclude with a clear conscience that similarly conclusive results associated...

This bachelor thesis is a literature review, examinig the effect of agricultural and nutritional measures on soil biological activity. Bachelor thesis is systematically divided into several parts. At the beginning of the thesis are included important dates regarding soil organic matter and edaphon. Another part of the work has been to study effects of fertilization and liming on soil biological activity. Furthermore, there are studies on the impact of agro-technical measures and the impact of the application of pesticides. The paper also lists methods of research soil biological activity.

The aim of this report is to describe the elemental composition and C:N:P stoichiometry of soil organic matter and microbial biomass in spruce swamp forests in the National Park Šumava and to find out whether they are affected by a presence of different plant dominants in the understory - peat moss, cotton-grass and blueberry. Samplings were made at three locations in the spring, summer and autumn of 2013. The work was a part of the project funded by the GA CR.

In bachelor thesis we evaluated biological parameters of selected subtypes of Chernozems. Object of study were -- Haplic Chernozem (Unčovice), Haplic Chernozem (Praha-Ruzyně) and Calcaric Chernozem (Velešovice). We determined total organic carbon content, humic substances content, microbial biomass and soil basal respiration. Further we evaluated the influence of tillage system and compost application onto selected parameters. Obtained results showed that compost application effected soil biological parameters.

Priming effects are fast short-term changes in the turnover of soil organic matter (SOM). Depending on sources of released CO2, priming effects are classified as real (acceleration of mineralization SOM) or apparent (release of CO2 due to accelerated microbial biomass turnover). Mechanisms causing priming effects remain poorly understood. Microbial competition, nitrogen limitation, microbial diversity changes, effect of living roots are the most often mentioned among mechanisms that cause priming effect. In my thesis I have studied intensity of priming effects in soil from post mining heap that vary in age and SOM content. These soils were affected by addition of substrates with different complexity (glucose, starch and cellulose) in two levels. Addition of 0.2 ml 1.75 % glucose, starch and cellulose solution resulted in statistically significant increase in CO2 release only in one soil. Addition of 0.8 ml 1.75 % glucose, starch and cellulose solution cause significant increase in released CO2 in 3 from 5 soils. Causes of these changes are not clear however in some cases it exceed level of added C could mean real priming effects connected to release already stored C. In soils where organic matter was accumulated on the soil surface and is not mixed into soil was observed the most strong priming...