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Long term dynamic of vegetation succession on post-mining sites.
Skalníková, Andrea ; Mudrák, Ondřej (advisor) ; Janíková, Eva (referee)
Spontaneous succession of vegetation can be one of the restoration approaches of disturbed sites after coal mining. It is therefore important to know the course of successional changes and whether it can be replicated. The spontaneous succession of vegetation on disturbed sites is usually based on monitoring of multiple sites of a different stage of succession. By their comparison the course of the succession over time is inferred. This approach of the study is called chronosequence (space-for-time substitution). Another option is to repeat monitoring of permanent plots, but it requires a long period of time to observe successional changes. Rarely are these approaches combined. In this thesis, I analyse the main trends in the succession of plant communities and their plants functional traits on five localities of various age during the 15 years. I have examined whether the localities follow similar successional trends. Data (plant coverage) were collected by annual resampling of 50 (ten per locality) permanent plots of 5 m x 5 m since 2007. By performing a multivariate CCA analysis, we analysed the species composition of the plant community, and by performing an RDA analysis, we analysed the changes in weighted averages of plant functional traits. In both cases, the localities and their...
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Ant succession in post mining sites
Hovorková, Marie ; Frouz, Jan (advisor) ; Mudrák, Ondřej (referee)
Succession is often studied by using a chronosequence. When using a chronosequence we study a set of sites with different ages at the same time and by comparing them we conclude what kind of changes occurred during time (space for time substitution). Only a few studies however compare how results obtained by using a chronosequence differ from those obtained by long-term studies. In my theses I repeated a study that investigated succession of ant communities on brown coal mining spoil dumps in Sokolov district after 19 years. There are chronosequences of two types of sites (spontaneous succession and recultivation) in Sokolov coal mining district. By repeating the original study I could compare changes that occurred du- ring time with changes along a chronosequnce. Relationship between occurrence of ant groups with different ecological requirements and age of site was also investigated. RDA model and variation partitioning were used to find out statistical significance between sites and their age. An increase in number of species was recorded on the spoil dumps. 22 ant species were found in the year 2020, from which 5 species were new on the dumps. All the new species are specialists, two of them are dendrophilous. A statistically significant increase in abundance of forest species with site age was...
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Primary Succession - study methods and pollen analysis opportunities
Suk, Pavel ; Abraham, Vojtěch (advisor) ; Prach, Jindřich (referee)
This thesis focuses on the main study methods of primary succession. It compares their advantages and disadvantages, the scales of usage and the outputs they bring. Due to the duration of a succession development (in hundreds of years), indirect approach - space-for- time substitution using chronosequences (sites that differ only in age and make up succession series) is often used instead of direct study methods. Breach of the the critical assumption that all sites follow the same trajectory may lead to false conclusions about the successional development. This thesis presents examples showing this problem, ways to prevent it and offers an alternative method - pollen analysis. Pollen analysis is on average used for larger spatial and temporal scales but partially overlaps scales of space-for-time substitution. The thesis presents biases of pollen analysis and ways how to solve/limit them and introduces abandoned, partially flooded quarries as a suitable environment for the use of this method to study succession inferred from rapidly growing limnic sediment.
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