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Relationships between body size, reproduction, and abundance in natural vegetationTracey, Amanda 31 July 2012 (has links)
According to traditional theory, superior competitive ability in plants generally requires a relatively large plant body size. Yet, within natural, crowded vegetation, most resident species are small, and species size distributions are right-skewed at virtually all scales. I aim to provide a potential explanation for this paradox: small species are able to coexist with and outcompete larger species because smaller species have greater ‘reproductive economy’—the ability for some seed production despite severe size suppression when under intense competition. Tracey and Aarssen (2011) found an isometric relationship between minimum reproductive threshold size (MRTS) and maximum resident plant size (MAX); however, a more accurate measure of maximum potential body size (MPBS) was needed (without competition), as typically the effects of competition are size-dependent. An isometric relationship, similar to Tracey and Aarssen (2011) was seen. Tracey and Aarssen (2011) also found that, contrary to the predictions of traditional theory, larger species were not more abundant (based on plot occupancy) in an old-field community. A more accurate measure of abundance was obtained by locating random 1 x 1 m plots and counting the number of ramets for each species in the plot. A significant negative relationship was seen between abundance and MRTS. This suggests that the most abundant plants in communities are not those that are bigger, or smaller, they are those with the smallest MRTSs. To test whether this relationship exists in other habitats, plots were located in different old-field, shrub-land and wood-land communities. Ramets for each species within the plots were counted, and the largest plant of each species was measured. Significant negative relationships between abundance and MAX plant body size were seen in the shrub-land and woodland sites; however, no relationship was detected in this old-field site. The data support the idea that smaller species have greater reproductive economy, but the mechanism remains unknown. These results suggest that a smaller plant body size results in more effective gene transmission into future generations in all habitat types and stages of succession and indicates a suggested paradigm shift in the predicted selection effects of competition on the evolution of plant body size. / Thesis (Master, Biology) -- Queen's University, 2012-07-30 11:56:23.999
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Lyčių aspekto poveikio ekonominei politikai vertinimas: Lietuvos atvejis / Assessment of the impact of the gender aspect on economic policy: Lithuania's caseKrinickienė, Eglė 16 June 2014 (has links)
Disertacijoje nagrinėjama aktuali lyčių aspekto poveikio ekonominei politikai vertinimo problema. Europos Sąjungoje lyčių lygybė pripažįstama viena iš pamatinių vertybių, o realus jos principų įgyvendinimas praktikoje bei suvokimas visuomenėje atspindi šalies pažangą ir išsivystymo lygį. Šio darbo tyrimo objektas – lyčių aspekto poveikis ekonominei politikai. Tyrimo tikslas – išanalizavus mokslinius požiūrius į lyčių lygybę ir lyčių aspekto integravimo strategiją, parengti lyčių aspekto poveikio vertinimo ekonominei politikai metodologiją, konceptualinį modelį, įvertinti lyčių aspekto poveikį makro ir mikroekonomikos lygiu bei pateikti rekomendacijas valstybinėms institucijoms įgyvendinant lyčių lygybės politiką. Disertacijoje atlikta kritinė lyčių lygybės teorijų ir strateginių lyčių lygybę įtvirtinančių dokumentų analizė bei įvertintos juose skelbiamos nuostatos, suformuota lyčių aspekto ekonominėje politikoje koncepcija, pasiūlyta lyčių lygybės tyrimo metodologija makro ir mikroekonominiu lygiu, sukurtas lyčių aspekto poveikio vertinimo ekonominei politikai konceptualinis modelis; pateiktas moterų rūpybos ekomikos indėlio į BVP įvertinimas; atlikta BVP, LR nacionalinio biudžeto ir užsienio prekybos analizė lyčių aspektu, lyčių padėties Lietuvos ir ES darbo rinkoje lyginamoji analizė bei pateiktas Lietuvos moterų verslo modelis. / The dissertation examines the topical issue of assessment of the impact of the gender aspect on economic policy. In the European Union, gender equality is recognised as one of the fundamental values, while the implementation of its principles in practice and the awareness of such principles in society reflect a country’s progress and level of development. The object of research of the dissertation is the impact of the gender aspect on economic policy. The aim of research is, upon analysing scientific approaches to gender equality and gender mainstreaming, to develop a methodology for assessment of the impact of the gender aspect on economic policy and a conceptual model, to assess the impact of the gender aspect at the macro- and micro-economic levels and to provide recommendations to authorities as regards the implementation of gender equality policy. The dissertation carries out a critical analysis of theories of gender equality and strategic documents stipulating gender equality and evaluates their provisions, formulates the concept of the gender aspect in economic policy, proposes a methodology of gender research equality at the macro- and micro-economic levels, develops a conceptual model of assessment of the impact of the gender aspect on economic policy; presents an assessment of the contribution of women’s care economy to GDP; carries out a gender analysis of GDP, the national budget of the Republic of Lithuania and foreign trade, a comparative analysis of the gender... [to full text]
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