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Power line disturbance model
Végh, Zoltán ; Zeman, Václav (referee) ; Mlýnek, Petr (advisor)
Requirements for existing PLC systems are very high (services requiring data rates higher than 1 Mbit/s). To meet these requirements, you must have a model of with real PLC environment. This document provides an overview of basic properties of noise in PLC systems, focusing mainly on the colored background noise, narrowband interferers, and various types of impulive noise in the PLC. Furthermore, different models of interference created by different literatures and simulation models were created with any significant adverse environmental effects of the PLC.
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Epigeická fauna v požářišti revíru Bzenec (LS Strážnice)
Prágr, Jakub
The aim of this thesis was to discover the actual condition of the epigeic fauna of a vast fire area (165 ha) in the first growing season after the fire in a habitat in Bzenec (LS Strážnice). Pitfall traps were used to determine the condition of the epigeic fauna. These were placed on sites deforested after the fire, in vegetation left to its natural successional development in a differentiated age after the fire and concurrently in unaffected vegetation. 16,267 specimens of 226 species of mostly epigeic fauna were caught. The impact of habitat conditions changed by the fire and timber harvesting were closely analysed for Carabidae, Araneae, Opiliones and Myriapoda taxons. There was a difference in the species composition of the epigeic fauna between the sites which were disturbed and undisturbed by the fire. Important factors that caused changes in the development and composition of the fauna after the fire were light conditions, humidity and trophic resources of the site. It was proved that the Pterostichus quadrifoveolatus (Carabidae) and Xerolycosa nemoralis (Araneae) species prefered the sites disturbed by the fire. The Carabus violaceus (Carabidae) or Harpactea rubicunda (Araneae) species were mostly bound to the sites undisturbed by the fire.
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Monitoring raných sukcesních stádií na plochách po velkoplošném rozpadu bučin
Valouch, Martin
This thessis deals with assessment of the actual state of an herb layer and regeneration in nature preservations Coufavá and Slunná. Both of nature preservations were affected large-scale wind disturbances. The survey was conducted in June and July 2013. There were totally performed 384 phytosocenological releves (162 in nature preserve Coufavá and 222 in nature preserve Slunná). Research was carried out on a regular grid 15 × 15 meters. There were 254 juvenile trees which were founded in nature preserve Coufavá and also 1891 juvenile trees were founded in nature preserve Slunná. In both of preservations browse didn't rise up 10 % from all regeneration. Most abundant tree species in nature preserve Coufavá were Fagus sylvatica. In nature preserve Slunná were most abundant Tilia sp. Strong clonal species dominated in disturbed desktop non-wood undergrowth in both of studied areas. In closed stand dominated typical forest species. Impatiens parviflora has abundant occurrence in both of biotopes. For both nature preserves was estimated future development and propose of solutions. Result of work should serve as a basis for optimizing the management plan for the said reservation.
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Natural disturbances in central-european mountain spruce forests. A basis for forest restoration
Edwards-Jonášová, Magda ; Čermák, Martin
Risk of natural disturbances is a frequently discussed topic in the context of mountain spruce forests and global climate change. Recently, large-scale natural disturbances such as bark beetle outbreaks and windfalls have appeared relatively more frequently in Central-European mountain spruce (Picea abies L.) forests, which led to the enforcement of salvage logging even in some protected areas. Our study was performed as part of a long-term observation of recovery of spruce forests aff ected by bark beetle and windfall with and without interventions in two Central-European national parks, Šumava National Park in the Czech Republic and Tatra National Park in Slovakia. Th e results proved the ability of spruce forests to recover unassisted even from stand-replacing natural disturbances. Th eir biological legacies, which include standing and lying dead wood, are important for natural regeneration of tree species, and provide critical habitats for particular forest species. In comparison to natural disturbances, the artifi cial disturbances resulting from salvage logging destroyed a substantial part of the natural regeneration, which led to the need for artifi cial reforestation. Th us, the non-intervention strategy appears to be the best option for restoration of disturbed forests in the zone of mountain spruce forests. Based on our results, we propose that natural disturbances be considered as a basis for forest regeneration and restoration of their natural structure.
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Analysis of tree growth on avalanche slopes in the Krkonoše Mts.
JANDOVÁ, Veronika
I applied dendrochronological methods to reconstruct snow avalanches in the Krkonoše national park. Tree-ring analyses are based on samples from Norway spruce (Picea abies),which is dominant species growing on selected avalanche slopes (Pramenný důl, Navorská jáma and Pančavská stěna). Mean growth curve were constructed for chosen localities and two different approaches were applied (detection of growth release and occurrence of resin ducts) for avalanche reconstruction.
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Strategies in aboveground space occupancy in herbs from disturbed habitats
BARTUŠKOVÁ, Alena
Disturbance is an important phenomenon affecting plant lives and shaping plant strategies in disturbed habitats. A variety of ecological concepts on individual plant response to injury has been proposed for specific natural ecosystems or growth forms. In central Europe, man-made habitats are often cases of disturbed places, so the aim of the thesis was to apply four chosen concepts on them. The thesis is composed of four original studies performed in two model ecosystems: recurrently disturbed ruderal place and regularly mown central European meadow. The occupying of the aboveground space after a disturbance event was studied here either as renovation of biomass or architecture. Regenerative strategies in herbs occupying disturbed habitats were described and confronted with concepts proposed originally for ecosystems subjected to natural disturbance regimes.
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