|
|
Impact of litter quality on decomposition
Vicena, Jakub ; Frouz, Jan (advisor) ; Cajthaml, Tomáš (referee)
The text of the thesis is divided into two parts. The literature overview discusses the importance of decomposition to carbon cycling in soils and evaluation of biological, physical and chemical factors that affect decomposition. To understand the factors affecting the soil respiration is essential to improve the global carbon balance. Decomposition affects also the release of nutrients, soil fertility and other soil processes and properties. The very project aims at the impact of leaf litter quality assessment (specifically, the C: N: P ratio) on the rate of decomposition. The assumption is that the low C:N ratio initially accelerates the decomposition which quickly reaches its minimum. Conversely, at a high C: N ratio the rate of decomposition is initially slower and subsequently reaches its minimum, and the average value of decomposition will be higher than in samples with low C:N ratio. For litter which has undergone leaching phase none of the significant differences in respiration of the individual samples with different C:N were statistically proved.
|
|
|
Influence of microbial community diversity on the decomposition of organic matter
Vicena, Jakub ; Frouz, Jan (advisor) ; Cajthaml, Tomáš (referee)
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...
|
|
|
Effects of litter raking on plant-soil interactions
Husinecká, Tereza ; Münzbergová, Zuzana (advisor) ; Hadincová, Věroslava (referee)
Plant litter creates variously sized layer on soil and provides significant source of nutrients, especially carbon and nitrogen, for the whole ecosystem. Decomposition of plant litter forms the main source of soil organic matter and is an essential part of the global nutrient cycle. It also provides habitat for many organisms living on the boundary of soil. Also, plant litter makes a barrier which the light is unable to penetrate. Terrestrial ecosystems are affected by human activity and are subject to disturbances, including litter raking. Litter raking has been an integral part of forest management for several centuries in the past, significantly affecting the character of vegetation and the soil environment. The aim of this work is to summarize the findings of studies dealing with the effects of litter raking on the interaction between plants and soil. The first part of the paper is devoted to the litter, soil environment and its components, which are connected to the litter and second part of the paper is devoted to the effect of litter raking on the nutrient cycle, acidification, plant diversity and seed germination.
|
|
|
Evolutionary history, systematics and biogeography of Southern Hemisphere hydrophilid beetles (Coleoptera)
Seidel, Matthias ; Fikáček, Martin (advisor) ; Gomez-Zurita, Jesus (referee) ; Gimmel, Matthew L. (referee)
The research presented in my PhD thesis consists of phylogenetic, biogeographic, taxonomic and ecological research of Southern Hemisphere water scavenger beetles (Coleoptera: Hydrophilidae) with a special emphasis on New Zealand. The introductory chapter provides a brief outline on the break-up of Gondwana and geological processes that shaped New Zealand and its fauna. Furthermore, the diversity of New Zealand Hydrophilidae and worldwide diversity of the hydrophilid subfamily Cylominae and its taxonomic history are illustrated. The scientific part of the thesis contains 4 published papers and 2 manuscripts. The first study recalibrates the Coleoptera time tree, providing new age estimates for the Hydrophiloidea, among others. The new age estimate is implemented in the second study, a phylogenetic study that reconstructs the biogeography of the 'Gondwanan' Cylominae beetles. The Cylominae, whose name was reinstated through nomenclatural priority over Rygmodinae in a separate paper, are found to consist of two tribes, Andotypini and Cylomini. The disjunct distribution of Cylominae is shown to be partly the result of vicariance and partly of long-distance oversea dispersal. The most remarkable long-distance dispersal is that of the only African representative of the subfamily which reached Africa from...
|
|
|
Structure and function of bacterial communities during succession on dead plant biomass
Tláskal, Vojtěch ; Baldrian, Petr (advisor) ; Marečková, Markéta (referee)
The decomposition of dead plant biomass substantially contributes to the carbon cycle and therefore is one of the key processes in temperate forests. While the role of fungi in litter and deadwood decomposition was repeatedly addressed, there are just a few surveys of bacteria associated with decomposing plant biomass. The development of bacterial community within leaf litter is likely driven by the changes in litter chemistry and by the availability of nutrients in the litter. Fungal activity greatly contributes to changing properties of substrate and thus influences bacterial community. Availability of nutrients is changing during biomass decomposition from easily accessible substrates toward more recalcitrant ones (e.g. lignin). The colonization of deadwood by bacteria is influenced by various factors such as microclimate conditions, tree species and volume. The aim of this thesis was to describe bacterial community dynamics during the first two years of decomposition of leaf litter and deadwood. In the leaf litter experiment, bacterial community was analysed in the live, senescent and decomposing leaves of Quercus petraea. This experiment was performed in the Xaverovsky Haj Natural Reserve, Czech Republic. Deadwood experiment was focused on the composition of bacterial community in the initial...
|
|
|
Influence of microbial community diversity on the decomposition of organic matter
Vicena, Jakub ; Frouz, Jan (advisor) ; Cajthaml, Tomáš (referee)
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...
|
|
|
Impact of litter quality on decomposition
Vicena, Jakub ; Frouz, Jan (advisor) ; Cajthaml, Tomáš (referee)
The text of the thesis is divided into two parts. The literature overview discusses the importance of decomposition to carbon cycling in soils and evaluation of biological, physical and chemical factors that affect decomposition. To understand the factors affecting the soil respiration is essential to improve the global carbon balance. Decomposition affects also the release of nutrients, soil fertility and other soil processes and properties. The very project aims at the impact of leaf litter quality assessment (specifically, the C: N: P ratio) on the rate of decomposition. The assumption is that the low C:N ratio initially accelerates the decomposition which quickly reaches its minimum. Conversely, at a high C: N ratio the rate of decomposition is initially slower and subsequently reaches its minimum, and the average value of decomposition will be higher than in samples with low C:N ratio. For litter which has undergone leaching phase none of the significant differences in respiration of the individual samples with different C:N were statistically proved.
|
|
|
Vliv okusu spárkatou zvěří na chutnost listového opadu pro mnohonožky (Diplopoda)
Ashili, P. ; Tajovský, Karel ; Tuf, I.H. ; Tufová, J.
Millipedes were used as a model group of decomposers for experimental study focusing on this aspect of ungulate - plant - soil invertebrate relationship. Leaf litter and millipedes (.i.Glomeris klugii, Glomeris hexasticha, Glomeris connexa, Julus scandinavius, Leptoiulus proximus, Megaphyllum projectum, Unciger foetidus./i.) were collected at forest localities in the Křivoklátsko PLA and BR, Czech Republic. Palatability of leaves from two different plots was compared. Leaf litter of beech (.i.Fagus silvatica./i.) and hornbeam (.i.Carpinus betulus./i.) was collected in autumn and spring in both plots and used in laboratory tests with millipedes. Consumption differed significantly between the individual experiments. Millipedes preferred hornbeam leaf litter over beech leaves, leaf litter from the fenced plot over that from the grazed plot, and fresh litter over old, overwintered leaves.
|
guest ::
