|
|
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.
|
|
|
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.....
|
|
|
Key factors affecting composition and diversity of saproxylic beetle assemblages
WEISS, Matthias
The thesis concerns the community structure of saproxylic insects with a heavy focus on beetles. It presents a review on change of insect assemblages along small-to-large scale gradients and the importance of saproxylic organisms in forest ecosystems. The fine-scale vertical stratification of saproxylic beetles assemblages and their differences between forests habitats of different latitude and altitude are investigated. Further, the importance of open-grown trees for saproxylic diversity is assessed.
|
|
|
Ecology of deadwood-associated fungi in the ecosystems of nature-like forests
Zrůstová, Petra ; Baldrian, Petr (advisor) ; Konopásek, Ivo (referee)
Dead wood plays an important role in forest ecosystems in the context of C dynamics, nutrient cycling, forest regeneration and biodiversity. Decaying wood sustains biodiversity by providing habitats and energy for fungi, bacteria, invertebrates, and many other organisms. Dead wood is resistant to decomposition and its decay is driven mainly by filamentous fungi. Community structure of wood- inhabiting fungi changes during decomposition, but the relationship between substrate quality and decomposer community is still poorly understood. This work studied fungal community composition with respect to tree species, stage of decay, volume and physico-chemical properties (such as pH, carbon and nitrogen content) of dead wood. Fungi were identified using next generation sequencing approaches - 454-pyrosequencing and Illumina MiSeq sequencing. Tree species, volume of dead wood (branches x logs) and stage of decay were the main variables affecting fungal community composition. Higher enzyme activities and content of fungal biomass indicate faster colonization of small branches than tree trunks by fungi. Fungal community composition, wood chemical properties and enzyme activities changed during decomposition. Both content of nitrogen and fungal biomass increased during decomposition. Enzyme activites peaked...
|
|
| |
|
| |
|
|
The role of wood decay fungi in the dynamics of a mountain spruce forest
POUSKA, Václav
This thesis is focused on environmental preferences of wood-decaying fungi and their relationships with forest structure and development. Relationships of fungi to properties of wood and forest stands were studied on the basis of field observations in Central-European mountain spruce forests. Plot-based approach was used to reveal a general pattern in the diversity of fungi within a single forest stand and between different stands. The analysis of stand structure provided a background for plot-based approach. Substrate-based approach was used to study single species preferences and their communities. In addition, the influence of wood properties (including fungi and their rots) on the regeneration of spruce on logs was studied.
|
|
|
Route belts as a organismus biotops
BABKA, Vladimír
Todays landscape is exposed to continually increasing human activities stress. The original biotopes are disturbed and fragmented from small to smaller segments. This fact can negatively influence the biodiversity. The railway line construction is a kind of such model, in this case its planed modernisation. This study deals with a railway embankment segment nr. 190 from Hluboká n. Vlt. to Zbudov. The aim of the work was to prove the railway line as an important and valuable biotope, which needs an enhanced attention. The vegetation biodiversity on four segments was studied. Totally 182 plant species were found with no rare species. The insect (beetles) species living in the wood of old trees were studied near the railway line. There were found 21 families with 52 beetle species where 3 species were rare. These important tree old stands were mapped too. The railway line history of this segment was processed too. The railway line creates a typical biotope with high vegetation biodiversity in this segment. The presence of the rare beetles living in the wood of old trees is more important.
|
|
|
Communities of xylophagous insects in floodplain forest: distribution and host specificity
VODKA, Štěpán
During the last century the forests of Central Europe changed from open woodlands to even-aged stands with closed-canopy. This change resulted in severe decline of forest biodiversity. This study examines how, and why such change affected xylophagous insects. I have studied microhabitat preferences, i.e. distribution of xylophagous insects in canopy and understorey of closed forests, forest edges and wooded meadows. I used method of rearing insect from timber baits exposed to ovipositing females of xylophagous insects in different situations in the forest at the beginning if vegetation season. After one season of exposition,the baits were collected enclosed in fly-wire cages, where emerging insects were collected for two seasons. This thesis consists of two parts: The first part is an unpublished manuscript dealing with effect of habitat insolation, vertical stratification, forest structure and amount of dead wood on community of long-horned beetles (Cerambycidae) and jewell beetles (Buprestidae) feeding on wood of pedunculate oak (Quercus robur). Baits were exposed in the canopy and the understorey of forest interior, the canopy and the understorey of forest edge and on solitary trees on wooded meadows. Most insect species do prefer insoled wood for their development, and were more common in the understorey than in the canopy. Insolation of bait was thus the prime factor affecting composition of reared insects. No relation was found between dead wood volume and species composition or abundance of reared insects This shows that insolation of the dead wood is crucial to conservation of most xylophagous insects. The second part of the thesis studies effect of vertical stratification and insolation on distribution of xylophages feeding reared from wood of 8 tree species (Alnus glutinosa, Populus alba, P. x canadensis, Salix alba, Carpinus betulus, Quercus robur, Tilia cordata, Ulmus laevis) and host specificity of xylophages. Results show that: (i) community composition of xylophages reflects evolutionary history of their host plants; (ii) communities reared from different trees exhibit different preferences for forest strata and insolation of the habitat, probably in connection to preferred growth conditions of the host plant, (iii) many xylophagous insect species exhibit strong preferences to insoled habitats, and are thus confined to forest edges in extensively managed forests as well as in unmanaged forest reserves.
|
guest ::
