In boreal forest streams, woody debris is an important habitat component. Stream invertebrates and salmonids such as brown trout benefit from in-stream wood. The studies presented in this thesis explore how drifting stream invertebrates respond to addition of fine woody debris, and how young-of-the-year (0+) brown trout behave in habitats with and without fine woody debris. The first paper reports results from a field experiment where fine woody debris was added to streams, and invertebrate drift was measured in order to detect impacts of the fine woody debris on drift density, biomass and taxon diversity. In the end of the season, the fine woody debris-affected drift samples showed higher density, biomass and taxon diversity than the control samples. In the second paper, I describe effects of fine woody debris on 0+ brown trout, studied in laboratory stream channels. Trout were tested in habitats without fine woody debris, with an intermediate fine woody debris density, and with a high fine woody debris density. Swimming activity and foraging time were significantly lower when fine woody debris was present than when it was absent. More time was spent sheltering at the high fine woody debris density than at the intermediate one. The increasing exploitation of fine woody debris for biofuel purposes should be considered in relation to the effects on brown trout and stream invertebrate habitat. / <p>Artikel 1 ingick i avhandlingen som manuskript med titeln "Effects of fine wood addition on invertebrate drift in boreal forest streams". Nu publicerad.</p>

"Identity: An Expression of Life Through Dance" is a reflection on the process of choreographing and performing a series of dances based on self-discovery and research on innovators of dance and their techniques.

One common consequence of ontogenetic niche shifts is that juveniles and adults of the same species often use different resources and habitats. Theory suggests that variation in productivity and/or habitat size for the respective life stage regulates size distribution of individuals and population biomass. Low resources/habitat availability for juveniles relative to adults results in populations with many small juveniles with high mortality and few but large adults, while the opposite situation results in a population with small and slow growing adults with high densities. I tested this theory using lake-living brown trout (Salmo trutta), where adults inhabit lakes and use connected streams for spawning and nurseries for juveniles. My hypothesis was that the relative habitat availability for juveniles respectively adults determines the size structure of adult brown trout in lakes. This was done by quantifying available stream habitats in relation to lake area via GIS analysis of 101 allopatric brown trout lakes in Sweden and Norway. My results showed that the proportion of large trout, mean length and maximum length decreased with increasing juvenile habitat in relation to adult habitat availability. This suggests that relative variation in availability of juvenile and adult habitats can affect the size structure of lake-living brown trout, most likely due to size dependent niche shifts and competitive and cannibalistic interactions. As the lake brown trout is highly valued both for commercial and recreational purposes, these findings can be highly valuable for sustainable management of the ecosystems services that the brown trout provides.

京都大学 / 0048 / 新制・課程博士 / 博士(農学) / 甲第21967号 / 農博第2357号 / 新制||農||1070(附属図書館) / 学位論文||R1||N5218(農学部図書室) / 京都大学大学院農学研究科地域環境科学専攻 / (主査)教授 近藤 直, 准教授 小川 雄一, 教授 清水 浩 / 学位規則第4条第1項該当 / Doctor of Agricultural Science / Kyoto University / DGAM

An experimental study has been conducted to develop a process allowing the creation of biologically accurate aerodynamic test models mimicking the slotted primary feather geometry of the Brown Pelican (Pelecanus occidentalis). Preserved examples of both a full Brown Pelican wing and a single primary feather were 3D scanned and digitally reconstructed using a combination of MATLAB and CAD software. The final model was then 3D printed as a collection of smaller components using a LulzBot TAZ 6 printer and Taulman3D T-Glase PET filament. After using various surface finishing techniques to improve the finish of all 3D printed parts, an assembly was designed to mount the model in the low speed wind tunnel at the California Polytechnic State University. Prior to aerodynamic testing, airfoil sections of the pelican wing were generated in CAD and several common airfoil measurements and characteristics were investigated. At a flow velocity of 5 m/s (Re ~1.21 x 105), wind tunnel smoke and laser visualization testing highlighted the vortex generation of multiple primary feathers, as well as large-scale flow deviations in the vicinity of the feathers. A total pressure rake and total pressure probe were used to create detailed plots of the ratio of the local velocity to free-stream velocity (Vx/Vx∞) at two planes downstream of the model, which revealed vortex positioning consistent with that predicted by smoke visualization testing and provided a metric by which to evaluate the relative strength of each vortex. The model creation process and wind tunnel testing results outlined here provide a strong foundation for future investigations into the potential aerodynamic benefits provided by the slotted primary feather geometry employed by the Brown Pelican and other large gliding avian species.

In recent years two new diseases, brown spot and black pit, have been observed on potatoes in South Africa. Brown spot symptoms appear on the foliage as small brown lesions, whereas black pit symptoms appear on the tubers as small dark sunken lesions. In this study the causal organism of brown spot and black pit of potatoes in South Africa was determined. During initial isolation, one fungus and two bacteria were isolated, which were included in the trial. Only the treatments where the fungal isolate was used in inoculation resulted in the development of brown spot lesions. The causal organism of brown spot and black pit were identified as Alternaria alternata which is consistent with other research. To better understand the spread of Alternaria alternata between the plants and/or tubers a pot trial was conducted. It was observed that when planting an inoculated seed tuber brown spot may develop on foliage. But the daughter tubers harvested from plants infected with A. alternata will not necessarily develop black pit. Daughter tubers are most likely infected by A. alternata during harvesting and black pit lesions develop in high humidity in storage. Cultivar resistance is one of the most important measures in controlling plant diseases. Cultivar susceptibility of thirteen South African potato cultivars (Avalanche, Buffelspoort, BP1, Fabula, Fianna, Frodo, Hertha, Labadia, Lanorma, Mondial, Pentland Dell, Up-To-Date and Van Der Plank) was evaluated. Pot trials showed that all the evaluated cultivars are susceptible to infection by Alternaria alternata. Various crops (tomatoes, cabbage, mustard, wheat, oats, tobacco and maize) were assessed to determine the host range of Alternaria alternata (potato pathotype) in rotation crops in South Africa potato growing regions. Of the crops evaluated, the pathogen was able to infect only tomato crops. Only wheat, maize and oats can safely be used in the crop rotation in South Africa, as various potato pathogens attack cabbage, mustard and tobacco plants. This study will lead to a better understanding of brown spot and black pit diseases of potatoes in South Africa and globally. The study emphasise the need for further research which will help to reduce brown spot and black pit diseases of potato. / Dissertation (MSc Agric)--University of Pretoria, 2013. / gm2014 / Microbiology and Plant Pathology / unrestricted

Orientador: Edson Luiz Lopes Baldin / Resumo: A soja, [Glycine max (L.) (Merrill)] é um dos principais grãos produzidos mundialmente, com o Brasil apresentando grande destaque em produtividade e exportação. Diversos fatores podem comprometer a produção desta leguminosa, no qual o ataque de insetos fitófagos possui grande relevância. Dentre os insetos-praga para a cultura da soja, Euschistus heros (Fabricius) possui grande importância pela alta incidência no campo e elevado danos ocasionados. Como alternativa à baixa eficiência dos métodos de controle e aplicações indevidas de defensivos químicos, este trabalho procurou avaliar a tolerância de quatro genótipos de soja frente ao ataque de E. heros (3 percevejos/planta) em diferentes fases fenológicas (R3, R5, R7, R3 até o final do ciclo e controle) a campo em duas safras, e respostas enzimáticas, analisadas em laboratório, após o ataque de E. heros em casa de vegetação durante a fase fenológica R5 por diferentes períodos de infestação (7, 14, 21 dias). Para isto, foi avaliado a campo a produtividade, peso de 100 grãos, número de vagens/ 10 plantas, número de grãos/10 plantas, retenção foliar e nível de danos ocasionados. Em casa de vegetação avaliou-se produtividade da linha central, número de vagens e número de grãos. Posteriormente, em análises químicas realizadas em laboratório, foram avaliadas as atividades das enzimas peroxidase, polifenol oxidase, catalase, superóxido dismutase e proteínas totais solúveis. Os genótipos ‘Conquista’ infestado em R3, ‘IAC 100’ infestado... (Resumo completo, clicar acesso eletrônico abaixo) / Mestre

The aim of the diploma thesis was to monitor the influence of grass in feed on fatty acid content in eggs. The experiment was carried out on Lohmann Brown Classic hybrids at the age of 12 weeks. Layers were divided into five groups. The feed was enriched by a 5% drop of Trifolium pretense, Trifolium repens, Medicago sativa and Lolium perenne. The control group were fed in a diet containing color-promoting additives. The fattening took three months. Egg samples were collected at the end of the month. Feedin and the power was run ad libitum. The effect of the addition of dried plants was significantly (P < 0,05) to the color of the yolk. A statistically significant (P < 0,05) incerease in palmitic acid in eggs was recorded during the experiment in eggs produced by laying hens which were in diet containing addition of Trifolium pretense and Medicago sativa. A demonstrable increase (P < 0,05) was also observed in laying hens which were fed with a mixture enriched with Trifolium pretense in percent α-linolenic acid content.

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