|
|
Tesařík alpský (\kur{Rosalia alpina}) v Ralské pahorkatině
KOVÁŘOVÁ, Pavlína
The Rosalia longicorn (Rosalia alpina; Linnaeus, 1758) is a protected saproxylic (deadwood-depending) beetle species. Thanks to its attractive colouring, it acts as an umbrella species important for biodiversity conservation. The beetle has disappeared from many places in the Czech Republic, with one of the last populations surviving in the Ralska upland. Using the capture-mark-recapture method, I estimated the local population size, and mobility of the species, and related the results to the data obtained in previous years. The outcome will support more efficient conservation strategies targeted at this species in the Ralska upland.
|
|
|
Habitatové preference, stanovištní dynamika a management hmyzu vázaného na staré stromy
PLÁTEK, Michal
The thesis presents studies on habitat preferences of beetles associated with senescent, open-grown trees and on dynamics and management of saproxylic habitats. It presents a brief insight into the current issues in the conservation of insects dependent on old trees. It presents the patterns of exploitation by a veteran tree specialist within old open-grown trees and the local patterns of tree exploitation by the same species at sites with different characteristics. Further, it presents a study of the effect of a prunning technique on formation of deadwood microhabitats, and also the importance of active interventions in closed-canopy forests for the communities in temperate lowland woodlands.
|
|
|
The importance of bacteria for deadwood decomposition in forest ecosystems
Némethová, Ema ; Baldrian, Petr (advisor) ; Bárta, Jiří (referee)
Forest ecosystems represent a huge reservoir of carbon. The volume of deadwood in managed forests is in the tens of m3 h-1, while unmanaged forests have the volume of deadwood in hundreds of m3 ha- 1. Deadwood is a substrate with a high potential for decomposition. However, deadwood is a specific habitat that has a high C/N ratio and changes due to ongoing decomposition. The C/N ratio decreases with increasing decay time. In addition to the C/N ratio, the pH also changes during the wood pulping process, due to the decomposition of plant biomass by fungi. Moreover, deadwood has a high impermeability. The main decomposers of dead wood are fungi. In addition to them, bacteria, which are numerous in deadwood, also contribute to decomposition. Bacterial communities that decompose woody biomass are affected by these factors, and their distribution is also affected by dead tree species. The aim of this study was to describe how bacterial communities associated with deadwood change during decay. The most significant factor in the decomposition by bacterial communities is the time of decay. Bacteria found in short-decaying wood (less than 16 years old) are more diverse than those found in long-decaying wood. Methylotrophic bacteria and N-fixing bacteria are common in short-decaying wood as well. N-fixing...
|
|
|
Estimation of the quantity of dead wood after windthrow through aereal images in Tuscany, Italy
Kutchartt, Ruedlinger Erico Heinz
Tuscany has suffered severe windstorms in the last five years, causing major damages to the forests. Quantifying the damage after these disturbances has been the main concern for authorities. The objective of this study was develop a new, cost effective methodology to estimate dead wood volumes post windthrow through remote sensing and GIS tools, testing a supervised photo-interpretation in combination with LIS and an unsupervised photo-interpretation called NCC through RGB images with 0.2 m GSD. Additionally, field-assessed were obtained as control data. The study area was conducted in the Tuscany region, where 10 areas were selected. The species affected were mostly conifers. The results obtained by the unsupervised were better than supervised, but both methods did not show statistically significant differences. The NCC method showed promising results, but mostly in big areas, where the results showed accurate volumes. On the other side, small areas are not suitable to be under NCC methods yet, due to the low accuracy obtained in the volumes in this study.
|
|
|
Dekompozice dřeva v horských temperátních lesích a jeho dopad na pedogenezi
Paták, Ondřej
This thesis deals with the monitoring of the impact of decaying wood on the soil characteristics and the related development of the soil profile. The subject of the research is the soils in the Žofínský prales National Nature Reserve in Novohradské mountains, with the predominant European Beech (Fagus sylvatica L.). Samples taken under the decaying stems are compared with the control samples of soils with the predominant leaf layer on the surface. In the soil beneath the beech stems, a significantly higher carbon content, higher pH, higher nutrient concentrations, lower exchange acidity, and mostly lower Al and Fe content were found. Decaying wood most affected the horizon A, more intense podzolization was not detected unambiguously.
|
|
|
Mineralization of nutrients during the process of spruce dead wood decomposition in the mountain forest
Višňová, Anna ; Hofmeister, Jan (advisor) ; Choma, Michal (referee)
Summary: This thesis is focused on collecting information on the importance of dead wood on biogeochemical cycles of chemical elements in the mountain forest ecosystems of central Europe. The goal of this thesis was to determine the concentration of various elements(C, N, P, Ca, Mg, K, Na, Mn, Al, Fe) in the coarse woody debris of spruce samples of different age, stage of decomposition which were collected in different localities in the national park Šumava. Another goal was to determine the speed of which these elements are released from the dead wood. The information on the quantity of different elements and the speed of their release is currently lacking and could lead to better understanding of various biogeochemical cycles of elements in the mountain forest. During the decomposition the concentration of the elements N, P, Al and Fe increased whereas the Kalium concentration decreased. The other elements' (C, N, Ca, Mg, Mn) concentrations varied. Carbon constituted approximately 50% of weight in all of the samples analyzed. We carried out a laboratory experiment based on decomposition of dead wood samples in various stage of decay during a period of six months. The released concentration of CO2 was measured at two to four weeks intervals. The release of CO2 continually decreased during the experiment.....
|
|
|
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...
|
|
| |
|
|
Saproxylic moths and their interaction with forest ecosystems
Rada, Patrik ; Horák, Jakub (advisor) ; Vladimír, Vladimír (referee)
The thesis deals with saproxylic moths (Lepidoptera). For many of them is their obligatory relation to the dead wood relatively little known. The thesis gives comprehensive knowledge about these species in the form of a literature review. It is based on the widespread modern definition of saproxylicity, so it covers a larger spectrum of species that are dependent by their development cycle upon wood.
The result is a summary of information about each saproxylic family and individual representatives. It is also the view of the issue of collecting insects, fruit body of fungi or wood that are hosted by insects and their subsequent rearing until the emerge of imagos.
Future research of this topic should be focused mainly on mapping of the occurence of these species and knowledge of their enviromental claims.
|
|
|
Ecology and management of dead wood in the aquatic ecosystems
Málek, Jakub ; Bače, Radek (advisor) ; Kjučukov, Petr (referee)
This paper discusses the influence of deadwood on aquatic organisms and animals found in the vicinity of waters. The thesis also analyzes the economic aspects of the occurrence of deadwood in relation to water management. The chosen issue was addressed on the basis of findings of studies already carried. The work globally compares the abundance and species diversity of macroinvertebrates and fish in the environment of deadwood and the environment without wood. Effect of deadwood on the occurrence of selected species found in the area of Czech Republic was determined from available resources. Depending on the theoretical knowledge and ascertained facts, the economic pros and cons of deadwood are compared here. This work verified that the dead wood actually positively affects the density and species richness of communities of aquatic organisms. Regarding the deadwood and the occurrence of selected animals, due to the absence of necessary data, no connection has been confirmed. In the case of the importance of deadwood in water management, only ambiguous results were found. The author acknowledged this hypothesis to be valid, however, based mainly on theoretical knowledge. Overall, the results of the work indicate that deadwood could also have some economic benefits in connection with its ecological values, and therefore it is important to devote more of the scientific work to this issue, and based on them, it would be possible to evaluate these benefits.
|
guest ::
