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Vliv světelných podmínek listnatých lesů I. a II. vegetačního stupně na epigeickou faunu pavouků
Surovcová, Kamila
The objective of the present study was to investigate the impact of canopy openness and associated light conditions on epigeal spider assemblages in abandoned coppice forests in order to develop conservation recommendations for forest management in lowland woodlands. In particular, I studied the effect of canopy openness gradient on species richness, abundance, functional diversity, community composition, conservation value, and degree of rareness of spiders. There was established transects reflecting the canopy openness gradient in each of the eight forest stand. A total number of 90 spider species, including high proportions of xeric specialist and red-listed threatened species. The peaks of conservation indicators, as well as spider community abundance, were shifted toward more open canopies . On the other hand, functional diversity peaked at more closed canopies followed by a rapid decrease with increasing canopy openness. Species richness was highest in the middle of the canopy openness gradient, suggesting an ecotone effect. Ordinations revealed the rapid species turnover along canopy openness gradient with presence of most conservationally important species in sparse and open conditions. The results show that the various components of biodiversity peaked at different levels of canopy openness. Therefore, the restoration and suitable management of such conditions (e.g. conservation thinning, coppice management) will retain important diversification of habitats in lowland oak forests. According to these results, even small-scale activities supporting these conditions could be suitable conservation tools to slow down the general decline of woodland biodiversity.
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Araneofauna dutin různých dřevin v okolí obce Hrotovice
Vymazalová, Pavla
Collection of spiders from fruit tree cavities was done in the period from 20th March 2014 till 20th January 2015 in Hrotovice surroundings. Among the total of 172 collected individuals there were identified 12 families. The most represented families are Clubionidae 23.8%, Gnaphosidae 20.3% and Dictynidae 19.2%. It was possible to identify just 55 of adult individuals into 14 species. The most represented species found on the surveyed sites was Micaria subopaca, which is an endangered species. Among other endangered species that occurs there were Clubiona marmorata and Lathys humilis. At the surveyed sites were also collected Pistius truncatus species and Pseudius encarpatus, which are the nearly threatened.
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Biogeography of arachnofauna of the Alps
Šilhavá, Alena ; Šťáhlavský, František (advisor) ; Řezáč, Milan (referee)
This bachelor thesis gives a summarizing overview of the biogeography of arachnofauna of the Alps. It covers five orders of arachnids residing in the Alps, namely scorpions (Scorpiones), pseudoscorpions (Pseudoscorpiones), palpigrades (Palpigradi), harvestmen (Opiliones) and spiders (Araneae). The work is focused on the distribution of endemic and subendemic species of these orders of arachnids and on factors that can influence their distribution and total diversity in the Alps. It turns out that temperature and humidity are important factors. Pseudoscorpions occur more frequently in warmer areas at lower altitudes, while especially scorpions of the genus Euscorpius (Alpiscorpius) and harvestmen are more tolerant to areas with a lower temperature, while harvestmen especially require sufficient humidity. For spiders in the mountains of the Alps total species richness and density decreases mainly from open land to the forest. Total diversity in the Alps has also been influenced by temperature oscillations during the Quaternary climatic changes and different positions and types of refugia. This is apparent at the species closely related to soil environment, such as palpigrades or cave pseudoscorpions of the family Syarinidae. Key words: biogeography, the Alps, endemic, Scorpiones, Pseudoscorpiones,...
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Succession of spider assemblages in quarries of Bohemian Karst
Siegelová, Eva ; Kubcová, Lenka (advisor) ; Korenko, Stanislav (referee)
In this thesis, the succession of spider assemblages in five limestone quarries of different ages in Bohemian Karst has been studied. The main goal of this paper was studying changes of spider assemblages along successional gradient. Furthermore, different environmental factors affecting spider communities and also assemblages of spider communites in different terraces of the quarry have been studied. Standardized methods (pitfall traps, hanging desk traps, shifting leaf litter, sweeping of herb vegetation, and beating shrubs) have been used for recording the highest possible richness of spiders. The results showed that position of the terraces and the age of the quarry do not affect species richness and density. Species density of epigeic spiders increased significantly with number of the plant species. The results showed that spiders do not have their own succession, but they are following vegetational succession. The environmental factors which affect species composition of spiders from the pitfall traps are positon of terraces, shading and moss cover. Although the age of the quarry was insignificant for spiders from pitfall traps, every quarry was inhabited by different spider communities. Shrubs and tree-dwelling spiders showed correlations with the age of the quarry. Data recorded from...
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Comparison of Arachnids from caves in selected parts of Balcanic and Alpine-Carpathian regions
Škopek, Zdeněk ; Šťáhlavský, František (advisor) ; Růžička, Vlastimil (referee)
This work presents comparison of cave arachnids in selected areas of Balcanic and Alpine-Carpathian regions. The work contains basic characteristics of studied regions, also characteristics of cave environment and explanation of important terms often used in relation to these habitats. Further, it concludes basic knowledge of all recent orders of arachnids to cave environment. It contains also detailed study of the best investigated groups of arachnids, and tries to explain some aspects, which influence the biodiversity on the matched area. Powered by TCPDF (www.tcpdf.org)
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Sublethal effect of agrochemicals on \kur{Pardosa} sp.
KRIŠTOFOVÁ, Lucie
In the last decades, there has been a growing interest in studying particular those arthropods who have an important role in agroecosystems. For example, they are natural enemies of pests and therefore they are considered to be beneficial organisms. However, these beneficial arthropods may be negatively affected by the application of chemicals under the management of agroecosystems and their potential to inhibit pests can be significantly reduced. Such organisms certainly include spiders which occure in abundant numbers practically in all types of terrestrial habitats including agricultural ecosystems where they have a role of very important predators. Therefore, the thesis focused on current issues of pesticides, especially from the view of their negative effects on behavioral modification of beneficial invertebrate organisms in agricultural crops. The theoretical part is devoted to a brief characteristics of pesticides, their sublethal effects on non-target organisms and the importance of spiders as natural regulators of pests in agroecosystems. The practical part describes the experiment whereconventionally used agrochemicals were tested the influence of the herbicide and desiccant Basta 15, the Arrest preparation and their combination (mixture Basta 15 + Arrest) on spiders genus Pardosa. I focused on the side effects of these solutions, specifically on the modification of predatory behavior and on the mortality of spiders. It has been shown that agrochemicals affect the predation successfulness of spiders. From the short term and the long term point of view, it has been shown that spiders treated with the tested preparations killed less prey than the individuals in the control group which were treated only with distilled water. The dependence of mortality and the number of killed prey on the size and sex has not been proved. Preparations Basta 15 and the mixture caused significantly higher mortality of spiders. The Arrest preparation did not increase the mortality.
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Interactions between spiders (Araneae) and their prey
Nerpas, Marek ; Korenko, Stanislav (advisor) ; Kysilková, Kristýna (referee)
Spiders (Araneae) are predators utilizing many strategies for hunting their prey. Their diet is often extensive. To obtain food, many various interactions occur among the spiders, and some species are not even afraid to hunt over other spiders. In the first two chapters, I describe the environment of spiders. I focus on the basic classification of spiders, following by an overview of the most important families in Central Europe and their division into the weavers of different types of cobwebs, and spiders who do not hunt through the webs but have a similar style of hunting, in hunting groups (guilds). Further on, the work deals with intraspecific interactions between spiders, such as competition, cannibalism or cooperation that influence the success in hunting prey and consequently the success in survival of spiders. In the last two chapters I deal with the interactions in the framework of the hunting groups, and between different hunting groups that affect other species of the ecosystem and are a driving force in shaping animal communities.
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Viniční terasy jako refugia pro výskyt xerotermních druhů pavouků (Araneae) a jejich bioindikační využití v hodnocení kvality životního prostředí a úrovně biodiverzity
Košulič, Ondřej
The large-scale decline of traditionally managed early-successional habitats caused by the joint effects of agricultural intensification and abandonment of marginal lands has resulted in a critical reduction of xerophilous arthopods throughout Europe. The question is whether newly generated early-successional sites of human-made habitats (in this case vineyard terraces) may partially compensate this habitat loss. My research, therefore, focusses on spiders as model organisms to determine the potential importance of xeric slopes of vineyard terraces for biodiversity conservation in agricultural landscapes. I analyzed species density, abundances, rareness degree and conservation value among vineyard terraces with two habitat types of different succession stages (sparse and dense grass turf) placed in in landscapes with varying proportions of surrounding potential source areas (steppe -- foresteppes) and different surrounding habitats (habitat structure) around studied terraces. During 2011 were collected by different methods 6040 adult specimens of spiders belonging to 171 species, 69 genus and 24 families. From this representation were calculated high proportion of rare xeric specialist (40 %) and red-listed threatened species (15 %). From the statistical analyses, overall species density and abundance of spiders did not differ significantly between the terraces with sparse and dense vegetation cover, however species density was significantly influenced by presence of xeric grasslands around vineyards. The occurence of rare and endangered epigeic was significantly associated with the type of successional stage (for epigeic and epiphytic species), as well as rareness degree, conservation value and abundances significantly increased with presence of adjacent steppe grasslands. The results indicate that artificial habitats, such as vineyard terraces, are important refuges for wide spectra of xerothermophilous spiders. To prevent losses of rare and endangered xeric species, I suggest some small scale management methods that maintain important microhabitat mosaic structures under the different succession stages.
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Characters used for determining of spiders (Araneae)
KRIŠTOFOVÁ, Lucie
This bachelor thesis focuses on a current issue of classifying spiders into their families. The incorrect recognitions of a family are often caused by inappropriate choice of morphological features and their ambiguous characteristics for determination usage. In a literary review, various morphological characters of spiders used for their determination to families are summarized and described. Subsequently, two Czech keys were tested by respondents, which provided a view of the steps and features causing difficulties in classifying spider families. Thus, I outline both unquestioning acceptance of features from older sources and the fact that their usage is not always a reliable tool for determination. Often neglected is the attitude of inexperienced observers who look upon the spider body inexpertly, not being influenced by arachnological traditions, and therefore, with a certain dose of exaggeration, objectively. This is the reason why the research was done mainly with the help of amateur public. In the final parts of the bachelor thesis, I both discuss problems that emerged and were recorded during the observation and recommend suitable improvements concerning the classification keys.
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Bezstavovce prezimujúce v ulitách suchozemských mäkkýšov v širšom okolí Vranova nad Topľou (Slovensko)
Štempáková, Kristína
The main aim of this work was the overwintering of spiders in land -- snail shells in vicinity of town Vranov nad Topľou. Collecting of these shells was carried out in the wintertime at the turn of 2012/2013 and 2013/2014. For the detection what species of spiders are overwintering there, were shells stored at room temperature. The outgoing species were caught, inserted into tubes with alcohol and determined later. From 1085 collected shells (Xerolenta, Cepaea, Helix), 116 spiders were obtained about 11% of the shells were inhabited. Thus, shells represented important refuge, as well as a way to hibernate, and oftentimes these shells are inhabited by rare or endangered species.
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