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The influence of forest management on occurence of microhabitats that are important for forest biodiversity
Heřmánková, Valentýna ; Hofmeister, Jan (advisor) ; Kozák, Daniel (referee)
A large part of the declining forest biodiversity (saproxylic insects, birds, fungi, bryophytes, lichens etc.) is linked to microhabitats that occur on structures typical of old-growth forests and are relatively rare in managed forests. In recent decades, alternative, more close-to- nature management practices have been slowly gaining ground, but their impact on microhabitats, and thus their potential value for forest biodiversity, has not yet been assessed. Therefore, I made a comparison of the occurrence and quality of microhabitats in 4 forest plots (8,3 to 42,5 ha) representing different forest management methods (traditional clearcutting management, alternative selective management and forest reservation at the time of data collection 65 years without intervention) in the natural conditions of the Central Bohemia. In the plots, using the adopted methodologies, I conducted an inventory of the presence of microhabitats on living trees and an inventory of deadwood and their assessment. The highest abundance and quality of microhabitats and deadwood were in the nature reserve, which at the same time completely exhausted the gamma diversity of all plots studied. The occurrence of microhabitats in clearcut and selective management forests was comparable and mostly low. The positive factors...
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The role of microhabitats in spatio-temporal differentiation of phytoplankton flagellates
Pusztai, Martin ; Němcová, Yvonne (advisor) ; Bílý, Michal (referee)
This thesis deals with factors structuring phytoplankton flagellates. The aim of the thesis was to investigate the role of microhabitats in spatio-temporal differentiation of lentic communities of these flagellates, which has not been rigorously examined to date. The study was conducted during 2010-2013 in the shallow littoral sites of Horní rybník, Rybníčky u Podbořánek Nature Reserve. Phytoplankton flagellates showed cyclic seasonal dynamics, which was reflected by significantly different community structure and species richness during the season. In contrast, silica-scaled chrysophytes showed a non- cyclic seasonal dynamics. The impact of the season was strongly correlated with the impact of fluctuating environmental factors - pH, conductivity and temperature. Gradient of interrelated environmental factors between the northern and southern shore together with microhabitat - substrate type played the major role and accounted for 64.4 - 75.8 % variability in the data. Microhabitat type (plankton, metaphyton, epipelon) significantly affected species richness and community structure also in the course of the season. A large number of species was assessed to prefer a certain type of microhabitat. These preferences were observed at both species and generic levels, and even at the level of the main taxonomic...
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Ecology,ethology and variability of european green lizard Lacerta viridis in Natural reservation Tiché údolí
Chmelař, Jan ; Rehák, Ivan (advisor) ; Moravec, Jiří (referee)
The European green lizard, Lacerta viridis, is in the Bohemia region stated as critically endangered species. Populations in this region are located beyond the northern border of continuous range of this species and are closely related to the "riverine phenomenon", and deeply engorged river valleys. The chosen locality in Tiché údolí is a subject to a long-term conservational management aimed to strengthen and maintain abundance of the local population. This management is a direct output of a previous study of this population performed in years 1995-1997. Main goal of the presented study is to compare current population characteristics with the older study. The locality has been visited 119 times in years from 2011 to 2014. The studied population now displays higher abundance and inhabits a larger area. The author also performed a spatial analysis of the places with presence of an observed individual in order to determine and evaluate significance of the chosen abiotic factors for habitat discrimination. The results indicate that positive discrimination is based on the presence of a rock debris and a hiding place. Strongest factors towards negative discrimination were high percentages of grass and high vegetation coverage. This study also contains and discusses ecological, ethological and...
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