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581	The influence of biophysical feedbacks and species interactions on grass invasions and coastal dune morphology in the Pacific Northwest, USA Zarnetske, Phoebe Lehmann, 1979- 09 September 2011 (has links) Biological invasions provide a unique opportunity to study the mechanisms that regulate community composition and ecosystem function. Invasive species that are also ecosystem engineers can substantially alter physical features in an environment, and this can lead to cascading effects on the biological community. Aquatic-terrestrial interface ecosystems are excellent systems to study the interactions among invasive ecosystem engineers, physical features, and biological communities, because interactions among vegetation, sediment, and fluids within biophysical feedbacks create and modify distinct physical features. Further, these systems provide important ecosystem services including coastal protection afforded by their natural features. In this dissertation, I investigate the interactions and feedbacks among sand-binding beach grass species (a native, Elymus mollis (Trin.), and two non-natives, Ammophila arenaria (L.) Link and A. breviligulata Fernald), sediment supply, and dune shape along the U.S. Pacific Northwest coast. Dunes dominated by A. arenaria tend to be taller and narrower compared to the shorter, wider dunes dominated by A. breviligulata. These patterns suggest an ecological control on dune shape, and thus, coastal vulnerability to overtopping waves. I investigate the causes and consequences of these patterns with experiments, field observations, and modeling. Specifically, I investigate the relative roles of vegetation and sediment supply in shaping coastal dunes over inter-annual and multi-decadal time scales (Chapter 2), characterize a biophysical feedback between beach grass species growth habit and sediment supply (Chapter 3), uncover the mechanisms leading to beach grass coexistence and whether A. breviligulata can invade and dominate new sections of coastline (Chapter 4), and examine the non-target effects resulting from management actions that remove Ammophila for the recovery of the threatened Western Snowy plover (Charadrius alexandrinus nivosus) (Chapter 5). I found that vegetation and sediment supply play important roles in dune shape changes across inter-annual and multi-decadal time scales (Chapter 2). I determined that a biophysical feedback between the beach grass growth habits and sediment supply results in species-specific differences in sand capture ability, and thus, is a likely explanation for differences in dune shape (Chapter 3). I found that all three beach grass species can coexist across different sediment deposition rates, and that this coexistence is largely mediated by positive direct and indirect species interactions. I further determined that A. breviligulata is capable of invading and dominating the beach grass community in regions where it is currently absent (Chapter 4). Combined, these findings indicate that A. breviligulata is an inferior dune building species as compared to A. arenaria, and suggest that in combination with sediment supply gradients, these species differences ultimately lead to differences in dune shape. Potential further invasions of A. breviligulata into southern regions of the Pacific Northwest may diminish the coastal protection ability of dunes currently dominated by A. arenaria, but this effect could be moderated by the predicted near co-dominance of A. arenaria in these lower sediment supply conditions. Finally, I found that the techniques used to remove Ammophila for plover recovery have unintended consequences for the native and endemic dune plant communities, and disrupt the natural disturbance regime of shifting sand. A whole-ecosystem restoration focus would be an improvement over the target-species approach, as it would promote the return of the natural disturbance regime, which in turn, would help recover the native biological community. The findings from this dissertation research provide a robust knowledge base that can guide further investigations of biological and physical changes to the coastal dunes, can help improve the management of dune ecosystem services and the restoration of native communities, and can help anticipate the impacts of future beach grass invasions and climate change induced changes to the coast. / Graduation date: 2012 / Access restricted to the OSU Community at author's request from Sept. 22, 2011 - March 22, 2012 ecosystem engineer invasive species coastal dune foredune wind tunnel species interactions Ammophila arenaria Ammophila breviligulata Elymus mollis beach grass Charadrius alexandrinus nivosus targeted management Oregon Washington ecosystem service coastal protection sediment supply Lotka-Volterra facilitation coexistence indirect effects sand supply species distributions sediment transport Elymus -- Ecology -- Northwest, Pacific Sand dunes -- Northwest, Pacific Sand dune ecology -- Northwest, Pacific Grasses -- Ecology -- Northwest, Pacific
582	L'évolution du droit de l'environnement au regard du concept de développement durable dans les pays de l'Afrique de l'Ouest francophone / The Evolution of Environmental Laws in connection with the concept of Sustainable Development in French-speaking west African countries Dohou, Hontongnon Expédit Léon 17 February 2015 (has links) Le concept de développement durable fut promu à la Conférence de Rio de 1992avec l’adoption d’un certain nombre d’instruments juridiques. Le droit africain s’estprobablement adapté aux règles et aux principes inhérents au concept avec, commeconséquence, la refonte ou la révision des codes ou lois de protection del’environnement. Face aux problèmes environnementaux récurrents, à la difficilegestion intégrée des ressources en eau, à l’opérationnalisation critique de la solidaritéà l’eau potable pour tous, à la gouvernance environnementale défaillante, la questionde l’évolution efficiente du droit de l’environnement africain au regard du conceptde développement durable se pose. Il se révèle un insuccès de la saisie du conceptpar le droit africain. Au final, un nouveau modèle de droit de l’environnement, auprofit des pays de l’Afrique de l’Ouest, s’avère nécessaire. / The concept of sustainable development was promoted in the Rio Conference in1992 with the adoption of a number of legal instruments. African law has probablyadapted to the rules and principles inherent to the concept with, as a consequence,consolidation or revision of codes and laws to protect the environment. Facingrecurrent environmental problems, the difficult Integrated water resources, criticaloperationalization of solidarity drinking water for all, the failed environmentalgovernance, the question of the efficient development of the law of the Africanenvironment in relation to the concept of sustainable development arises. It proves afailure in the seizure of the concept by the African law. Finally, a new model ofenvironmental law in favor of the countries of West Africa is necessary. Principes Règles Santé environnementale Participation au processus décisionnel Installations classées Air Sol Forêts primaires Sylviculture Biodiversité Eau Zones humides Solidarité à l'eau Espèces invasives Espèces aquatiques Modes traditionnels de protection Eie Ees Rse Gouvernance Partenariat Éducation Solidarité Principles Rules Environmental health Participation in decision making Classified facilities Air Soil Primary forests Forestry Biodiversity Water Wetlands Solidarity water Invasive species Aquatic species Traditional methods of protection Eie Ees Rse Governance Partnership Education Solidarity 340
583	Mekanisk uppgrävning: ett effektivt verktyg mot den invasiva främmande arten gul skunkkalla (Lysichiton americanus) : En utredning av behandlingsmetoder Kekäle, Oscar January 2023 (has links) Den biologiska mångfalden minskar globalt och ett av de största hoten utgörs av invasiva främmande arter. Natura-2000 området Fylleån, Halland, huserar en av de största svenska populationerna av gul skunkkalla (Lysichiton americanus). Arten utgör ett hot mot de naturvärden som finns i Fylleån och är subjekt för extensiva behandlingsarbeten i området för att motarbeta växtens effekt på ekosystemet. Det finns i dagsläget ingen evidens för att behandlingsmetoderna som presenteras av Naturvårdsverket och Havs- och vattenmyndighetens metodkatalog har effektivitet i svenska vattendrag. Målet med min studie är att undersöka effektiviteten av mekanisk uppgrävning samt ytlig hetvattensbehandling som behandlingsmetoder för gul skunkkalla. Jag undersöker även lämpligheten för användandet av övriga metoder presenterade av metodkatalogen och metoderna hetvattensbehandling och fröställningsborttagning som inte listats i metodkatalogen men som testas av myndigheter i viss utsträckning. Den första delen av studien genomförs som jämförelsestudie mellan områden som behandlats i olika grad med mekanisk grävning och hetvattenbehandling för att bestämma metodernas effektivitet. Den andra delen av min studie var att genom en litteraturgenomgång med metodkatalogen som utgångspunkt avgöra lämpligheten på och reflektera över metoderna samt reflektera över metodernas lämplighet att användas civilt. Min slutsats är att mekanisk grävning ger minskande populationer och signifikanta skillnader i individantal, förutsatt att behandlingen utförs rätt och konsekvent. Jag resonerar att andra behandlingsmetoder kan påverka mer organismer än vad man avsett och att de därför är olämpliga att bruka i Fylleån. Jag diskuterar vad jag anser är rimligt idéellt arbete i nuläget samt framtida potential och behovet av information i rätt kanaler. / Biodiversity is decreasing globally and one of the biggest threats is invasive alien species. The Natura-2000 area Fylleån, Halland, houses one of the largest Swedish populations of the American skunk cabbage (Lysichiton americanus). The species poses a threat to the natural values found in Fylleån and is subjected to extensive treatment to counteract the plant's effect on the ecosystem. There is currently no evidence for the effectiveness of the treatment methods presented by Naturvårdsverket and Havs- och vattenmyndighetens method catalog in Swedish watercourses. The goal of my study is to investigate the effectiveness of mechanical excavation and superficial hot water treatment as treatment methods for American skunk cabbage, along with hot water treatment and seed stand removal which are not listed in the method catalog but are tested by authorities to a certain extent. Through a comparative study between areas treated to varying degrees with mechanical digging and hot water treatment, I determine the effectiveness of the methods. The second part of my study was to try to determine the suitability of and reflect on the methods, as well as reflect on the suitability of the methods for civilian use through a literature review using the method catalog as a starting point. My conclusion is that mechanical digging produces declining populations and significant differences in found individuals, provided the treatment is carried out correctly and consistently. I reason that other treatment methods can affect more organisms than intended, and that they are therefore unsuitable for use in Fylleån. Invasive species Yellow skunk cabbage American skunk cabbage Lysichiton americanus Ecology Botany IAS Halland Plants Nature Methodolgy Mechanical digging hot water treatment heatweed glyfosate climate Lysichiton Araceae inventory species description statistical analysis litterature review watercourse invasive plants Sustainability Biology Natural sciences Halmstad university Invasiva främmande arter Gul skunkkalla Lysichiton americanus Ekologi Botanik heatweed Araceae IAS Halland Växter Natur Behandlingsmetoder Mekanisk uppgrävning hetvattenbehandling glyfosat klimat kalleväxter inventering artbeskrivning statistisk analys metodkatalogen litteraturgenomgång vattendrag invasiva växter globala målen hållbarhet Biologi Naturvetenskap Högskolan i Halmstad Natural Sciences Naturvetenskap Biological Sciences Biologiska vetenskaper Ecology Ekologi Botany Botanik

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