Plant-soil feedback is an important mechanism in plant communities affecting their species composition. Understanding plant-soil feedback is crucial for describing the interactions between plant communities and their soil communities. The effects of plant-soil feedback can be positive, negative or neutral and because of these changes plants are either coexisting or competing. Plant-soil feedback is often studied within plant succession, plant invasion and plant dominance in a plant community. In these cases, the nature and strength of influence of each species is studied. Despite the large number of previous studies on plant-soil feedback, very little is known about the temporal and spatial changes of the intensity of plant-soil feedback and the intraspecific variability in plant-soil feedback. The aim of my work was to observe the temporal changes in the plant-soil feedback of a species growing in soil which was conditioned by the same or other plant species. Another goal was to explore spatial changes in plant-soil feedback. The last objective was to test differences in the intensity of plant-soil feedback among different genotypes of one species. The results of my work demonstrated that the intensity of intraspecific plant-soil feedback of Rorippa austriaca is negative and increases with...

TITLE: Natural communication with the horse and the possibilities of human - horse interaction AUTHOR: Bc. Lenka Volfová DEPARTMENT: Department of Biology and Enviromnental Studies (Katedra biologie a enviromnentálních studií) SUPERVISOR: PhDr. Kateřina Jančaříková, Ph.D. ABSTRACT: This thesis explores interspecies communication and, specifically, natural communication between the man and the horse. Through comparative research based on a programme developed by Ing. Josef Liška (Liška Solutions) for the assessment of the participant's personality, employing several exercises with a horse from the ground, the thesis aims at introducing ways in which horses can be used for the purposes of personal growth. For the purposes of this thesis, volunteers from three groups were assessed under this programme using the method of direct observation: teachers, business executives and people who work with animals. The assessment was carried out by marking down points and comments. On the basis of the results obtained, the above three groups were subsequently compared among one another. The research shows that teachers excelled in six out of seven observed personal competencies while, compared to business executives, there is still space for improvement in terms of their energy. The results shown in relation to the...

The study is focused on comparative ecology of three closely related species from Myosotis palustris group. Importance of various functional traits of individual species was evaluated experimentally in the greenhouse (germination experiments), in the pot experiment and in the reciprocal transplant field experiment. Germination, production of clonal structures and response to various environmental conditions (competition, moisture conditions, etc.) were studied. The experimental data are supplemented with an analysis of phytosociological relationships of the studied species.

While animal steroid hormones are very well known and have been studied for a long time, in plants no steroid substances were known until relatively recently. Only in the second half of the past century brassinosteroids were discovered; later on, their hormonal function in plants was confirmed. Still a lot of unknown remains as regards their function in plant cells. This paper presents in its first part the evidence that brassinosteroids control in maize (Zea mays L.) grown under field conditions not only its morphology and yield but also some developmental/reproduction characteristics like e.g. number of female inflorescences or speed of the development of male inflorescences. Particular response of a plant depends, however, on the type of applied brassinosteroid, its concentration, and last but not least also on a particular maize genotype and developmental stage of the plant during applicatin. Impact of brassinosteroids on primary photosynthetic processes in plants has not been proven under these conditions, neither on the activity of photosystem (PS) I nor on the Hill reaction. No statistically significant differences in the content of photosynthetic pigments have been found either. Another topic dealt with in this thesis is the possible protective influence of brassinosteroids on plants...

This thesis compares four methods of therapeutic riding to determine what communicative competence are developed in the framework of activities with the use of horses. The work includes terminology section, which are explained in terms accompanying the whole job and explains the term of use for therapeutic riding. The theoretical part introduces the social communications horses and interpersonal communication. The next section presents the specifics of interspecies communication, and its use in the development of communicative competence and follows the chapter on the development of communicative competence through activities with the use of horses. The main part describes the four methods of therapeutic riding and analytically compares the contents of individual activities with horses focused on the development of communicative competence. In conclusion summarizes the results and encourages the formation of methodology developing communicative competence in educational programs with horses.

In recent decades, it was shown that belowground competition for some plants may take form of the tragedy of the commons (TOC). In these plants, the competing neighbours invest more in root systems than would be appropriate for optimal nutrient uptake for the group and also more than they do when grown alone. However, there is also strong evidence that other species do not follow TOC, and tailor their root system to best nutrient exploitation irrespectively of competitor presence. The root investment strategy of these plants should correspond to the ideal free distribution (IFD). In my thesis I focus on two aspects:  I use game theoretical models to explore, whether those strategies can coexist within species and also whether different species can coexist if they have different strategy. From this model I draw predictions, which I test by meta-analysis.  Using Agrostis stolonifera as a model, I test assumptions on nutrient and neighbour perception, which underlie TOC and IFD models. I show that according to mathematical models, those two strategies can coexist in different species in a community, but cannot coexist within a species. Within a species, the TOC strategy should always dominate, once it appears. This can be extrapolated to macroevolutionary scale - once TOC occurs in certain clade, it should...