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1	Srovnání efektivity obranných opatření proti lýkožroutu smrkovému (Ips typographus (L.)) na vybrané lokalitě Lesního Závodu Boubín. / Effectiveness of protective measures against spruce bark beetle (\kur{Ips typographus} (L.)) at selected localities of LZ Boubín VAČKÁŘOVÁ, Tereza January 2013 (has links) The efficiency of various protective measures against the Spruce bark beetle (pheromone-baited traps, trap trees, poisoned traps - tripods.) and the impact of insecticide-treated trap trees on non-target organisms were studied in weekly periods in areas in the altitude of 1000m above sea level. Tree traps proved to be of much higher effectivity with an average of 3307 caught spruce bark beetles in comparison with pheromone-baited traps with only 457 beetles within the same period. Poisoned traps ? tripods baited with pheromone (FeSex Typo, producer ? Karel Ubik, CR) were more effective than pheromone traps and the average number of caught beetles was 1226. Among non-target insects caught in these traps were 61 species included 7 orders. The most common species was Thanasimus formicarius.
2	Effects of Environmental Variables on Four Aquatic Insect Taxa among Smaller Water Bodies of Different Ages on Farmland; A Pilot Study Jaggwe, Assad January 2015 (has links) High anthropogenic modification like infrastructural development, drainage, eutrophication, dumping garbage, is a threat to biodiversity of smaller water bodies in agricultural landscapes. However, smaller water bodies have historically been constructed for drainage, waste treatment and other purposes. Further, new small water bodies are now being constructed in agricultural areas in Sweden, mainly to remove nutrients and to improve landscape biodiversity. This creates two different age classes (old and new) of smaller water body habitats. I sampled aquatic insects in 27 smaller water bodies of varying types and ages in Halmstad region and related insect biodiversity, species richness, composition structure to environmental variables. I partitioned the region into two locations (Northern and Southern) for easy data comparison and due to difference in topography. The data was analysed using a Canonical Correspondence (CCA) and regression analysis. The CCA results show a difference in the species composition between old and new sites. The most important variables in explaining species assemblage structure was age of the aquatic water bodies. The species richness decreased with increase in nutrient concentration (total phosphorus) according to regression analysis. Species composition and diversity were related to Vegetation and tree cover in and around the water body. The results of my study shows that the older the water bodies the better for specific species like Aeshna cyanea and the new water bodies tolerate more specimens. My results suggest that, as there is need to facilitate plant growing, protecting vegetation and trees to better mimic natural conditions of water bodies, creating new water bodies while protecting aged water bodies is important for conservation of biodiversity. Water bodies Age Insect species Biodiversity Agricultural land Conservation Environmental Sciences Miljövetenskap Miljö- och naturvårdsvetenskap Ecology Ekologi
3	Consequences of Insect Flight Loss for Molecular Evolutionary Rates and Diversification Mitterboeck, T. Fatima 25 May 2012 (has links) This thesis investigates the molecular evolutionary and macroevolutionary consequences of flight loss in insects. Chapter 2 tests the hypothesis that flightless groups have smaller effective population sizes than related flighted groups, expected to result in a consistent pattern of increased non-synonymous to synonymous ratios in flightless lineages due to the greater effect of genetic drift in smaller populations. Chapter 3 tests the hypothesis that reduced dispersal and species-level traits such as range size associated with flightlessness increase extinction rates, which over the long term will counteract increased speciation rates in flightless lineages, leading to lower net diversification. The wide-spread loss of flight in insects has led to increased molecular evolutionary rates and is associated with decreased long-term net diversification. I demonstrate that the fundamental trait of dispersal ability has shaped two forms of diversity—molecular and species—in the largest group of animals, and that microevolutionary and macroevolutionary patterns do not necessarily mirror each other. / Generously funded by NSERC with a Canada Graduate Scholarship and the Government of Ontario with an Ontario Graduate Scholarship to T. Fatima Mitterboeck; NSERC with a Discovery Grant to Dr. Sarah J. Adamowicz evolution flight transitions insects molecular rates diversification flightless flight loss dispersal holometabola insect species species richness effective population size population size population subdivision macroevolution microevolution comparative method substitution rates dN/dS ratios non-synonymous substitutions nearly neutral theory molecular clock mitochondrial DNA nuclear DNA OXPHOS COI COX1 Cytochrome c oxidase subunit I pterygota speciation extinction whole-tree method sister-group method

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