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Influence of neonicotinoids on insect communities with focus on bees
Weingartová, Barbora ; Erban, Tomáš (advisor) ; Šípek, Petr (referee)
The bachelor thesis is focused on pesticides and their impact on the environment. Plant protection products must undergo a comprehensive assessment involving the impact on nontarget organisms. Negative effects of pesticides are not only assessed in humans and other vertebrates but also in invertebrates. Pollinators that play a vital role in ecosystems are an important group for evaluation. This thesis specializes in a group of pesticides called neonicotinoids, some of which are currently banned in some countries. This thesis mentions array of neonicotinoids, their toxicity and effects on pollinators that were observed. Reassessment is crucial in order to make a comprehensive picture of whether the ban was correct. . Keywords: pesticides, neonicotinoids, pollinators, honeybees, bumblebees, colony collapse disorder
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Human Hormonal Drugs and their Residuals in Aquatic Ecosystems
Řehounková, Michaela ; Vytlačilová, Jitka (advisor) ; Kašparová, Marie (referee)
Human hormonal drugs are used to adjust the function of the endocrine system, therapeutics of hormone-dependent tumours, or as part of contraceptive and anti-inflammatory preparations. Those pharmaceuticals contain active substances structurally and chemically similar to endogenous hormones. Above mentioned drugs and their residuals can get into the wastewater after they are metabolised in the human body, or by the illegal disposal of them, and they are removed in the wastewater treatment plant (WWTP). The most efficient technologies for removing hormonal drugs, particular oestrogens, from wastewater are ozonolysis and sonolysis. Concentrations in wastewater are determined by gas and liquid chromatography. The concentration of oestrogens in the waters of the Czech Republic (Vltava River) is ranging from 1.3 to 3.8 ng / l, and their levels in drinking water does not mean an increased health risk for consumers. The effects of oestrogen residuals are demonstrable on aquatic organisms, such as changes in the regulation of endocrine system, reproductive disorders and disorders in embryogenesis.
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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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Impact of genetically modified maize expressing Cry3Bb1 toxin on the non-target organisms.
SVOBODOVÁ, Zdeňka
Presented study compares impacts of the GM maize MON 88017 and the non-transgenic maize on the non-target invertebrates. The Diabrotica-resistant and herbicide-tolerant GM maize may become important for most of Europe as the spred of Diabrotica virgifera virgifera LeConte continues but its implementation has been hindered by fears of undesirable environmental effects. I confirmed that MON88017 expresses the insecticidal Cry3Bb1 toxin but I found no evidence of any negative impact on the monitored species. Both the composition and the species abundances of invertebrate communities were similar to those in the stands of the conventional non-transgenic maize varieties.
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