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Vlivy pesticidů používaných ve vinohradnické praxi na necílové organizmy
Surovcová, Kamila
Fungicides are among the most widely used agrochemicals in the world. These pesticides are mixed with wetting agents (surfactants), which improve in particular the physical properties of the fungicides. In recent years, the consumption of wetting agents has grown. Unfortunately, it was not investigated their direct effect or the synergistic effect, which can adversely affect on non-target organisms, but in this study the effect of fungicides, surfactants and their combinations (the so-called synergistic effect) on non-target organisms was investigated. The research was focused on the sublethal effect of individual products. Test spiders belonged to the Philodromus genus. This genus was chosen due their high predatory ability, which is going in winter months too. Spiders of the genus Philodromus are also the most abundant spiders on vineyards and fruit orchards. Spiders were subjected to the application of test preparations in laboratory conditions. After application of the chemical preparation, they were followed for two days and fed with fruit flies. Based on their predatory ability, the impact of individual chemicals and their sub-lethal effects was assessed. Research has shown that the Karathane New fungicide in combination with the Trend 90 surfactant reduced predatory ability of females, but did not show this effect in males group. Vice versa, the combination of IQ Crystal fungicide and Trend 90 surfactant increased the predatory ability of males. This study demonstrated the synergistic effect of fungicid preparations and surfactants. The research will continue due to the unusualness of this issue.
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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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