Many freshwater ecosystems sustain several invasive species. Here I examine multiple invasions in two highly invaded and well catalogued catchments; Lake Naivasha, Kenya and River Thames, England. New metrics, derived from stable isotope analysis, are used to provide measures of trophic diversity and to examine dietary interactions among species. I test the hypothesis that functionally similar sympatric species will occupy a smaller niche than their allopatric counterparts. Additionally, I quantify the impact of multiple invasive species on ecosystem structure and functioning in order to address the question; do interactions among species amplify or mitigate one another's impact? In Lake Naivasha, the stable isotope metrics revealed serial replacement of invasive species due to dietary interactions. Invasive red swamp crayfish were eventually excluded from the lake due to niche restriction in the presence of a more recent invader, the common carp. Now, the crayfish have migrated into the catchment where they overlap with a species of native river crab. Here, I found a novel mechanism of invasion, whereby the crayfish restricted their niche at the invasion front in order to reduce competition with crabs. Crayfish also caused significant changes in invertebrate community structure and increased decomposition rates, which indirectly resulted in displacement of the crabs. In the Thames catchment, I catalogue the non-indigenous species and show how invasion rates have increased significantly since 1800 due to globalisation. Using the four species of invasive crayfish present (red swamp, signal, Turkish and virile), I demonstrate their extensive diet plasticity using novel measures of niche width and individual specialisation based on stable isotope data. Interactions among the crayfish were examined and this revealed that each species has varying and independent impacts on invertebrate community structure, algal standing stock and decomposition rates. Hence, interactions among invaders are not expected to amplify or mitigate one another's impact and instead, the combined impact will be the sum of their allopatric impacts.

This paper expands existing understandings of how entertainment content viewers conceptualize, encounter, evaluate, and select entertainment video content in the emerging television ecosystem. Special attention is paid to the influences that create awareness around a particular media product and the decision-making dynamics that influence viewers as they move through the selection process. Patterns of awareness, discovery, selection, and adoption relevant to a theoretical understanding of media content choice are identified and discussed.

Innebörden av begreppet   ekosystemtjänster och värdet av dessa behöver spridas och förankras i   samhället i större utsträckning än vad som görs idag. Det har bland annat   uppmärksammas i ett av etappmålen inom de nationella miljökvalitetsmålen. Med   anledning av detta har Naturvårdsverket fått i uppdrag av regeringen att   genomföra en kommunikationssatsning om ekosystemtjänster, där det   övergripande målet är att öka förståelsen för den biologiska mångfaldens och   ekosystemtjänsternas värden samt deras betydelse i samhället.   Naturvårdsverket har inom ramen för detta regeringsuppdrag tagit fram en   vägledning för att integrera ekosystemtjänster i myndigheters verksamhet.   Vägledningen, som presenterades i november 2016, är indelad i fem steg och   vänder sig främst till centrala och regionala myndigheter men även till   kommuner. Med anledning av att vägledningen är ny så finns det få exempel på   hur vägledningens 5-stegsmetod kan tillämpas i praktiken. Denna fallstudie är   ett första exempel på hur den föreslagna 5-stegsmetoden kan användas inom en   nationell myndighet vilket gör fallstudien unik i sitt slag. Fallstudien   omfattar vildsvinsförvaltning och tar sin utgångspunkt i Naturvårdsverkets   förvaltningsplan för vildsvin. I enlighet med vägledningens metod hölls en   workshop på Naturvårdsverket där personer från tre olika enheter medverkade.   Under workshopen identifierades och diskuterades möjliga kopplingar mellan   vildsvin och ekosystemtjänster, både i form av direkta ekosystemtjänster som   vildsvinen tillhandahåller, men även i form av de miljöeffekter som   vildsvinen har på ekosystemtjänster av både positiv och negativ karaktär.   Vidare diskuterades även förslag på hur detta skulle kunna integreras i en   uppdaterad version av nuvarande nationella förvaltningsplan för vildsvin.   Workshopen resulterade i en bruttolista på relevanta kopplingar som i ett   nästa steg bör verifieras genom att stämma av resultatet med aktuell   forskning, något som gjorts i begränsad utsträckning i denna fallstudie på   grund av tidsmässiga skäl. Däremot jämfördes den bruttolista med relevanta   kopplingar som identifierats i nuvarande nationella förvaltningsplanen för   vildsvin. Resultatet visade att 5-stegsmetoden hjälpte till att identifiera   tio nya kopplingar mellan vildsvin och ekosystemtjänster, främst inom   kategorin kulturella ekosystemtjänster. Dessutom bidrog resultatet till fler   infallsvinklar samt en mer nyanserad bild av de kopplingar som redan berörs i   den nuvarande nationella förvaltningsplanen för vildsvin. Sammanfattningsvis   erbjöd vägledningen ett användbart verktyg för att systematiskt identifiera   relevanta ekosystemtjänster samt belysa påverkan på dessa. Det har ett värde   inom viltförvaltningsarbetet, både i enlighet med den nationella   förvaltningsplanen för vildsvin som är ämnad att revideras i takt med att ny   kunskap genereras och nya erfarenheter, och i enlighet med Naturvårdsverkets   Strategi för Svensk Viltförvaltning som förespråkar att viltförvaltningen ska   vara adaptiv och hela tiden utvecklas genom ny kunskap. Att identifiera   relevanta ekosystemtjänster bidrar dessutom till att uppnå ett av etappmålen   inom de svenska miljömålen som säger att ”senast år 2018 ska betydelsen av   biologisk mångfald och värdet av ekosystemtjänster vara allmänt kända och   integreras i ekonomiska ställningstaganden, politiska avväganden och andra   beslut i samhället där så är relevant och skäligt”. / The meaning of the concept ecosystem services and their values needs   to be disseminated and established to a greater extent than it is today   which, for instance, are acknowledged in one of the milestone targets among   the Swedish Environmental Objectives. With that in mind, the Swedish   Environmental Protection Agency has been given a mandate from the Government   which comprises communication efforts regarding ecosystem services where the   overall objective is to increase the understanding of biodiversity and the   values of ecosystem services, including their importance to society. As a   result, the Swedish Environmental Protection Agency has developed guidance in   order to integrate ecosystem services in authorities’ activities. The   guidance, which was presented in November 2016, is divided into five steps   and is primarily to be used by central authorities, as well as county administrative   boards or municipalities. However, there are currently few examples available   regarding how to practically apply this 5-step method. Thus, the purpose of   this case study is to present the first example of how the 5-step method can   be used within a central authority, which makes this case study unique of its   kind. The case study focuses on wild boar management and Sweden’s national   management plan for wild boar. A workshop was held at the Swedish   Environmental Protection Agency in accordance with the 5-step method and   people from three different units participated. Possible connections between   wild boar and ecosystem services were identified and discussed during the   workshop, both in terms of direct ecosystem services provided by wild boar,   but also in terms of the positive or negative impacts that wild boar has on   ecosystem services. Possible ways to integrate these findings into an updated   version of the national management plan for wild boar were also discussed.   The workshop resulted in a “gross list” of relevant connections, which, as a   next step, needs to be verified by adding findings from current research.   This has only been done to a smaller extent in this case study due to a   limited timeframe. However, the gross list was compared to relevant   connections that could be identified in the current national management plan   for wild boar. The results showed that the 5-step method helped to identify   ten new connections between wild boar and ecosystem services, primarily   within the category of cultural ecosystem services. The discussions during   the workshop also contributed to a deeper understanding of the connections   that had already been identified in the current national management plan for   wild boar. In summary, the guidance provided a useful tool to systematically   identify relevant ecosystem services and to address the impacts on these   services. The identified connections has a value for wildlife management   work, both in accordance with the national management plan for wild boar   which is intended to be updated when new knowledge and new experiences are   generated, but also in accordance to the Swedish Environmental Protection   Agency’s Strategy for Swedish Wildlife Management which also says that   wildlife management should be adaptive and constantly developed through new   knowledge. To identify relevant ecosystem services also contributes towards   achieving one of the milestone target within the Swedish Environmental   Objectives, which says that “the importance of biodiversity and the value of   ecosystem services are to be generally known and integrated into economic   positions, political considerations and other decisions in society where it   is relevant and reasonable to do so”. / <p>2018-07-17</p>

Submitted by JOSIANE SANTOS DE OLIVEIRA (josianeso) on 2018-12-19T13:33:26Z No. of bitstreams: 1 Rosiane Serrano_.pdf: 10021768 bytes, checksum: 5103415853700bb1beda3d9969bf2c13 (MD5) / Made available in DSpace on 2018-12-19T13:33:26Z (GMT). No. of bitstreams: 1 Rosiane Serrano_.pdf: 10021768 bytes, checksum: 5103415853700bb1beda3d9969bf2c13 (MD5) Previous issue date: 2018-09-27 / CNPQ – Conselho Nacional de Desenvolvimento Científico e Tecnológico / O esporte é constituído por uma cadeia de relações que influencia econômica e socialmente o meio em quese desenvolve. Assim, o tema desta pesquisa é a cadeia produtiva do esporte, em particular, a cadeia produtiva do futebol. O futebol agrega valor econômico para a sociedade à medida que oferece um produto capaz de influenciar a vida das pessoas que dele compactuam direta ou indiretamente. Nessa perspectiva, este trabalho propõe compreender sistemicamente o esporte enquanto um ecossistema produtivo para que se possa amplificar a agregação de valor econômico deste para a sociedade. Para atender a esseobjetivo, este estudo utiliza métodos múltiplos de pesquisa. Para tanto, inicia-se com o desenvolvimento de uma revisão sistemática de literatura do tema em questão. A partir da revisão, emergem proposições para a coleta de dados, que foi realizada por meio de entrevistas com especialistas em futebol. A análise de dados coletados é realizada com basena análise de conteúdo e, posteriormente, os elementos elencados pelas entrevistas suportam o desenvolvimento dos modelos de Ecossistema de Valor do Futebol, de análise sistêmica e de avaliação dos pontos de alavancagem, por meio de um Modelo de Dinâmica de Sistemas. Como resultado, a pesquisa aponta que o futebol agrega valor diretamente à sociedade a partir de seu Demonstrativo de Valor Adicionado, e indiretamentepor meio de ganhos de terceiros com o clube, no caso hotéis e rentabilidade de jogos. / The sport consists of a chain of relations that economically and socially influences the environment in which it develops. Thus, the theme of this research is the sport’s productive chain, in particular, the soccer’s productive chain. Soccer adds economic value to society as it offers a product capable of influencing the lives of people who directly or indirectly cope with it. From this perspective, this work proposes to understand the sport as a productive ecosystem, systemically, so that it can amplify its economic value to society. To meet this goal, this study uses multiple search methods. To do so, it begins with the development of a systematic literature review of the subject herein addressed. From the review, proposals for data collection emerge, which were carried out through interviews with soccer specialists. The data analysis was carried out based on the content analysis and, later, the elements listed by the interviews support the development of the Soccer Value Ecosystem models, of systemic analysis and evaluation of leverage points, by means of a Model of Systems Dynamics. As a result, research points out that soccer adds value directly to society from its Added Value Statement, and indirectly through third-party winnings with the club, in the hotels case and game profitability.

Adaptation is necessary to cope with, or take advantage of, the effects of climate change on socio-ecological systems. This is especially important in the forestry sector, which is sensitive to the ecological and economic impacts of climate change, and where the adaptive decisions of owners play out over long periods of time. These decisions are subject to experienced and expected impacts, and depend upon the temporal interactions of a range of individual and institutional actors. Knowledge of, and responses to, climate change are therefore very important if forestry is to cope with, or take advantage of, the effects of climate change over longer timescales. It is important to understand the role of human behaviour and decision-making processes in the study of complex socio-ecological systems and modelling is a method that can support experiments to advance this understanding. This study is based on the development of CRAFTY-Sweden; an agent-based model that allows the exploration of Swedish land-use dynamics and adaptation to climate change through scenario analysis. In CRAFTY-Sweden, forest and farmland owners make land use and management decisions according to their objectives, management preferences and capabilities. As a result of their management and location characteristics they are able to provide ecosystem services. To explore future change, quantitative scenarios were used that considered both socio-economic development pathways and climatic change. Simulations were run under the different scenarios for the period 2010-2100, for the whole of Sweden. Furthermore, because institutions (i.e. organisations) also influence socio-ecological systems through their actions and interactions between them and with land owners and the environment, a conceptual model of institutional actions applied to socio-ecological systems was developed. The application of this conceptual model was explored through a model of institutions that can act, interact and adapt to environmental change in attempting to affect ecosystem service provision within a simple forestry governance system. I found that forestry in the future will likely be unable to meet societal demands for forest services solely on the basis of autonomous adaptation. A northward expansion of agriculture and especially of forestry proved positive for both sectors to adapt to changing conditions, under several scenarios, given the substantial land availability and the improved environmental conditions for plant growth. Legacy effects of past land-use change can have a great impact on future land-use change and adaptation processes, especially in forestry. Also, greater competition for land may lead to shorter forest rotation times. Socio-economic change and land owner behavioural differences may have a larger impact on owner competitiveness, land-use change and ecosystem service provision than climate-driven changes in land productivity. Different owner objectives and behaviour resulted in different levels of ecosystem service provision. Also, particular forest types were differently suitable for adaptation depending on the sets of objectives under which they were managed. Owners implementing particular management strategies can be differently competitive under different future scenarios, and the suitability of such strategies for adaptation is not a static, inherent characteristic of a system. Instead, it evolves in response to changing contexts that include both the external global change drivers and the internal dynamics of agent interactions. Additionally, institutional conceptual models as presented here can support better understanding of the key institutional decision-making dynamics and their consequences, endogenously, flexibly across different socio-ecological systems. Finally, study limitations, future research and the policy relevance of findings are discussed.

Esta tese é o resultado de uma extensa investigação a respeito do processo criativo pessoal que envolve a invenção de um ecossistema como poética artística. Ela é a resposta para a possibilidade de construir uma poética visual coerente baseada nos conceitos biológicos de ecossistema e simbiose que envolva construções escultóricas a partir de objetos cotidianos banais de pequeno tamanho, encontrados principalmente no ambiente doméstico. Baseada nas experiências pessoais prévias, dedicadas ao objeto na arte, e focada na busca por objetos comuns passíveis de produzirem interação simbiótica foi construído um conjunto de trabalhos envolvendo objetos, fotografias, pessoas e o espaço, os quais foram ordenados para melhor identificação segundo suas características quanto ao suporte e ao procedimento técnico. São eles: a) conjuntos simbióticos verticais, que podem ser compartimentados, livres ou mistos - aqueles cujo substrato de apoio é vertical como a parede; b) conjuntos simbióticos horizontais - aqueles cujo substrato de apoio é horizontal; c) trabalhos fotográficos - trabalhos originados a partir da fotografia e, d) trabalhos macro visíveis - trabalhos confeccionados a partir de lentes ou que as requerem para melhor serem vistos. A partir de organizações de montagem intencionadas para proporcionar maior proximidade e intimidade do espectador através de movimentos do corpo, os trabalhos instigam a percepção da escala das coisas bem como dá vistas aos objetos ínfimos imperceptíveis no cotidiano. A articulação teórico-prática acontece levando-se em conta diferentes estudos relacionados ao objeto principalmente na voz de Abraham Moles, Jean Baudrillard e Gaston Bachelard. Além de dialogar com designers e diversos artistas cujas obras tangenciam aspectos desta pesquisa, articulamos reflexões com o pensamento do curador Agnaldo Farias sobre o objeto na arte contemporânea. Defendemos que o lugar para pequenos objetos no contexto da arte contemporânea é um ecossistema inventado no qual o espectador é convidado a interagir e deixar-se levar por sua fantasia e imaginação da mesma maneira que somos conquistados pelas palavras e imagens de um livro infantil. / This Thesis is the result of an extensive investigation of the personal creative process involving the invention of an ecosystem as artistic poetics. It is the answer to the possibility of building a coherent visual poetics based on biological concepts of ecosystem and symbiosis, involving sculptural constructions from banal daily objects of small size, mainly found at home. Based on previous personal experiences, dedicated to the object in art and focused on the search for common objects capable to produce symbiotic interaction, I built a body of work involving objects, photographs, people and space, which were ordered for better identification according to their characteristics of support and technical procedure. They are a) vertical symbiotic sets, which may be compartmentalized, free or mixed - those works whose substrate support is vertical as the wall; b) horizontal symbiotic sets - those works whose substrate support is horizontal; c) photographic works - works originating from photography; and d) macro visible work - work made from lenses or require them to best be displayed. From intentioned assembly organizations to provide greater closeness and intimacy of the spectator through body movements, the work instigate the perception of things scale and gives views to tiny inconspicuous objects in daily life. The theoretical and practical articulation occurs taking into account different studies related to the object mainly in the thinking of Abraham Moles, Jean Baudrillard and Gaston Bachelard. In addition of dialogue with designers and several artists whose works tangent aspects of this research, I articulate reflections with the thought of the curator Agnaldo Farias about the object in contemporary art. I argue that the place for small objects in the context of contemporary art is an ecosystem created, in which the spectator is invited to interact and let themselves be taken away by their fantasy and imagination in the same way that we are conquered by the words and images of a children's book.

A restauração florestal é mais do que somente plantar árvores. É necessário que haja o monitoramento do desenvolvimento da floresta no que diz respeito tanto a parâmetros estruturais e florísticos, mas também aos processos ecológicos. Esses processos propiciam as interações entre as espécies e promovem a funcionalidade do sistema, provendo serviços ecossistêmicos. Por isso, é necessário, além de monitorar o crescimento da vegetação, avaliar se o ecossistema está operando da forma como seria esperado. O objetivo desta tese é abordar questões referentes aos processos ecológicos e atributos funcionais em áreas florestais em processo de restauração. No primeiro capítulo, foi realizada uma revisão sistemática com o intuito de identificar os processos ecológicos e as variáveis que são medidas em estudos de restauração florestal. Os três capítulos seguintes foram baseados na coleta de dados em três sítios de estudo, situados no Estado do Rio Grande do Sul, Brasil. Foram coletados dados em florestas que tiveram intervenções de restauração (com aproximadamente 10 anos de desenvolvimento), bem como em florestas de remanescentes (utilizadas como sistema de referência). Além da amostragem da vegetação arbórea, foram coletados dados de diversos processos ecológicos, relacionados à ciclagem de nutrientes (decomposição, detritivoria e qualidade da serapilheira e do solo), produtividade (biomassa arbórea acima do solo e biomassa de folhas) e recrutamento (regeneração natural), bem como informações sobre atributos foliares, reprodutivos e de crescimento das espécies. Os resultados obtidos para cada um dos capítulos indicaram que: (1) os processos mais comumente avaliados foram aqueles relacionados à ciclagem de nutrientes, seguido por resiliência do ecossistema, produtividade, relações hídricas e interações bióticas; além disso foi identificado que os resultados positivos das ações de restauração nos processos ecológicos aumentam a medida que os sítios se tornam mais antigos; (2) áreas em restauração ainda diferem de suas respectivas florestas de referência para quase todas as variáveis analisadas, mas, ao contrário da nossa expectativa inicial, as diferenças foram maiores quando considerados os parâmetros estruturais da vegetação, indicando que os processos ecológicos podem se restabelecer antes mesmo da floresta atingir sua completa complexidade estrutural; (3) as variáveis que mais afetaram os processos ecológicos foram aquelas relacionadas aos atributos funcionais, tendo a riqueza de espécies na comunidade apenas um papel secundário na variação dos processos ecológicos estudados; além disso, tanto variáveis de composição funcional, quanto de diversidade funcional tiveram influência nos processos; e (4) modelos utilizados para avaliar a semelhança funcional entre restauração e referência indicaram que a comunidade presente no sub-bosque da restauração apresenta uma maior semelhança funcional com o sistema de referência do que a comunidade do dossel, indicando que as espécies utilizadas nos plantios diferem consideravelmente em sua composição funcional das áreas de referência. Esse estudo ressalta a importância de se compreender melhor os processos ecológicos em ecossistemas florestais e sua aplicação na avaliação do funcionamento de áreas em processo de restauração. O monitoramento desses sítios deve ser realizado a longo prazo de forma a verificar as variações ao longo do desenvolvimento florestal e avaliar as trajetórias sucessionais, sugerindo ações de manejo se necessário. / Forest restoration is more than just planting trees. It is required that forest growth is monitored both by measuring structural and floristic parameters, but also ecological processes. These processes provide interactions among species and promote ecosystem functionality, also offering important ecosystem services. Thus, it is necessary that besides monitoring vegetation growth, it should be evaluated if the ecosystem is operating as would be expected. The objective of this thesis it to address questions related to the ecological processes and functional traits in forests sites undergoing restoration. In the first chapter, we performed a systematic review in order to identify the ecological processes and the variables measured in forest restoration studies. The following three chapters were based on data collected in three study sites, located in the State of Rio Grande do Sul, Brazil. We collected data in forests subjected to restoration (approximately 10 years-old) and more conserved forests not subjected to restoration (used as reference ecosystem). Besides sampling tree components, we collected data on several ecological processes, related to nutrient cycling (decomposition, detritivory and litter and soil quality), productivity (aboveground tree biomass and litter biomass) and recruitment (natural regeneration), as well as information on leaf, reproductive and growth traits of species. The results obtained for each chapter indicated that: (1) the processes that were more frequently measured were the ones related to nutrient cycling, followed by ecosystem resilience, productivity, water relations and biotic interactions; additionally, we identified that positive results of restoration interventions on the ecological processes increased as sites became older; (2) restoration sites still differed from their reference ecosystems for all variables evaluated, but opposed to what we initially expected, these differences were even greater when we considered the structural parameters from the vegetation, suggesting that ecological processes may recover even before the full reestablishment of forest complexity; (3) the variables that most affected ecological processes were the ones related to functional traits, and community species richness had only a secondary role in the variation of ecological processes; in addition, both variables related to functional composition and functional diversity affected the ecological processes evaluated; and (4) the models used to evaluate functional similarity between restoration and reference indicated that the community growing in the understory of the restoration site is functionally more similar to the reference than the canopy community, suggesting that the species used in restoration plantings differ considerably in functional composition from reference sites. This study highlights the importance of ecological processes in forest ecosystems and its application in the evaluation of the functioning of sites undergoing restoration. Monitoring of these sites should be performed for a long period, in order to verify changes during forest growth and to evaluate sucessional trajectories, suggesting management actions if necessary.

L’aptitude des symbioses rhizobium-légumineuses à fixer l’azote atmosphérique, peut offrir d’importants services aux agro-écosystèmes. Cependant, associés à des contraintes biotiques (i) absence et/ou (ii) inefficacité symbiotique des rhizobiums du sol, des facteurs abiotiques (i) excès d’intrants azotés et/ou (ii) carences en phosphore (P) peuvent limiter la fixation symbiotique d’azote (FSN). Le Myo-inositol hexakisphosphate (phytate), principale composante de P organique (Po) du sol, représente une potentielle source de P disponible du sol, bio-disponible pour la plante, en lien à des activités phytases microbiennes, minéralisatrices du phytate. Afin de rechercher des rhizobiums, symbiontes de Vicia faba, efficaces dans l’utilisation du P (EUP) pour la FSN, nous avons réalisé un diagnostic nodulaire multilocalisé, en agro-écosystèmes sud de France. Le niveau d’efficacité d’utilisation de la symbiose rhizobienne (EUSR), en intra- et inter-placettes agricoles et en conditions hydroaéroponiques en serre, a été déterminé en corrélation des biomasses aériennes et nodulaires de plants de V. faba, à floraison. Parmi 59 isolats de V. faba, 26 sont aptes à minéraliser le phytate (Phy +), en milieu solide et six d'entre eux confirment une activité phytase, en culture liquide. L’intérêt d’une sélection de rhizobiums locaux aptes à une EUP pour FSN, nous a conduits à une avancée dans la sélection de marqueurs moléculaires phytases pour le criblage d’isolats rhizobiens Phy+. Mots ClésRhizobium, diversité, phytase, féverole, Vicia faba, nodulation, France-sud, agro-écosystème. / The ability of rhizobium-legume symbiosis to fix atmospheric nitrogen can provide important services to agro-ecosystems. However, associated with biotic constraints (i) missing and/or (ii) phosphorus (P) deficiency, can limit symbiotic nitrogen fixation (SNF). Myo-inositol hexakisphosphate (phytate), the main soil organic P (Po) component, represents a potential source of soil P available for plant P bio-availability, connected with microbial phytate-mineralizing activities. In order to look for rhizobium-Vicia faba, in P use efficiency (PUE) for SNF ability, nodular diagnosis was performed from a multi-location survey in an agro-ecosystem in South France. The efficiency in use of rhizobial symbiosis (EURS) was deduced from V. faba nodule and shoot dry weight values at flowering state, and compared in intra- and inter agricultural fields and in greenhouse hydroaeroponic conditions. Among 59 V. faba isolates, 26 were able to mineralize phytate (Phy+) in solid medium and six of them confirmed phytase activity in liquid culture. Looking for local rhizobiums with PUE for SNF ability, led us to a forward step in molecular marker selection for Phy+ rhizobium isolate screening. KeywordsRhizobium, diversity, phytase, faba-bean, Vicia faba, nodulation, South-France, agro-ecosystem.

Les espèces protistes ont été traditionnellement classifiées comme des plantes ou des animaux en raison de l’absence ou présence des chloroplastes. L’état actuel de la connaissance indique qu’un grand nombre d’espèces protistes portent des chloroplastes mais que physiologiquement elles sont capables d’utiliser l’autotrophie (photosynthèse) ou l’hétérotrophie pour se nourrir. La combinaison de ces deux modes trophiques par une même cellule est nommée mixotrophie. Chez les protistes l’hétérotrophie peut s’effectuer soit par la consommation des particules par phagocytose, e.g. des proies bactériennes, ou bien par l’absorption des composants organiques dissouts, i.e. osmotrophie. La mixotrophie est de plus en plus décrit chez les protistes dans tous les habitats aquatiques. Les écologistes du plancton constatent la récurrence de la mixotrophie chez les formes traditionnelles « phyto»plancton et micro »zoo »plancton. Cependant, identifier et quantifier la mixotrophie reste toujours un défi méthodologique. Dans cette étude nous nous sommes intéressés à la mixotrophie chez les espèces phytoplanctoniques marines, en particulier à leur nutrition phagotrophique de proies bactériennes. Nous avons testé des techniques modernes afin d’identifier la mixotrophie dans des cellules phytoplanctoniques. La technique cytogénétique d’hybridation in situ Card-FISH en utilisant de sondes d’ARN ribosomique 16S a été effectuée suivant des protocoles existant pour des bactéries et des protistes. Cette technique s’est avérée être un outil précieux pour visualiser des groupes phylogénétiques bactériens en association avec le phytoplancton à l’aide de la microscopie à épifluorescence, sans avoir besoin d'un isolement préalable des cellules ou des interférences avec l'association microbienne. Cependant, la méthode a échoué pour visualiser mixotrophie chez le phytoplancton car la sonde eubactérienne générale(EUB338) combine une large gamme d'espèces phytoplanctoniques, ce qui rend impossible de discriminer les signaux fluorescents provenant de tissus bactérienne ou phytoplanctonique. Le contexte de ces études est le phytoplancton et les bactéries hétérotrophes lesquels constituent des principaux concurrents pour les nutriments inorganiques dissouts. Dans le cas où la croissance bactérienne est limitée par le carbone, l'augmentation de la concentration de carbone organique dissous(DOC) renforce la croissance bactérienne et la consommation de nutriments dissous et ainsi affecte négativement la croissance du phytoplancton autotrophe. Cependant, les consommateurs de bactéries, i.e.phytoflagellés mixotrophes, peuvent être favorisés dans de telles situations car la hausse de DOC donne lieu à l'abondance plus élevé des proies bactériennes.En outre, nos résultats indiquent un potentiel effet positif de la température sur le mode de nutrition hétérotrophe de l’espèce, ainsi qu’une croissante contribution des espèces mixotrophes au sein des communautés de phytoplancton dans des conditions des hautes températures des eaux de surface de la mer. / Protist species were traditionally classified morphologically as either „plants“ or „animals“, based on the absence or presence of chloroplasts. State of science is that a high number of protist species carrychloroplasts but are nutritionally able to employ both autotrophy (photosynthesis) and heterotrophywithin a single cell. This combination of autotrophic and heterotrophic mode of nutrition within a single species is named mixotrophy. In protists, heterotrophy can be realized either by the uptake of food particles (e.g. bacterial prey) through phagocytosis or by the uptake of dissolved organic compounds (i.e.osmotrophy). Mixotrophy is globally and increasingly described in protists from all types of aquatic habitats. Plankton ecologists nowadays assess mixotrophy among the traditionally typified “phyto”plankton and mikro”zoo”plankton species as regularity. Nevertheless, detection and quantification of mixotrophy is still a methodological challenge. In this study, we focused on mixotrophy in marine phytoplankton species and put emphasis on its phagotrophic nutrition from heterotrophic bacterial prey. State of the art methodology was tested to visualize mixotrophy in single phytoplankton cells. Catalyzedreported deposition-fluorescence in situ hybridization (Card-FISH), using 16S ribosomal RNA probes,was employed based on existing protocols for bacteria and protists. The method proved to be a valuable tool to visualise bacterial phylogenetic groups in association with phytoplankton by epifluorescence microscopy without need for prior isolation of cells or interference with the microbial association.However, the method failed to visualize mixotrophy in phytoplankton since the general eubacterial probe(EUB338) hybridised a broad range of phytoplankton species making it impossible to discriminate fluorescent signals originating from bacterial or phytoplankton tissue. Background of these studies is phytoplankton and heterotrophic bacteria being major competitors for dissolved inorganic nutrients. In case that bacterial growth is carbon limited, increasing concentrations of degradable dissolved organic carbon (DOC) enhance bacterial growth and consumption of dissolved nutrients and there by negatively affect autotrophic phytoplankton growth. Bacteria consuming mixotrophic phytoflagellates, however, may gain in importance in such situations since DOC provokes higher bacterial prey supply.In addition, our results indicate a potential positive effect of temperature on O. minima´s heterotrophic nutrition mode, and indicate a potential increasing contribution of mixotrophic species to phytoplankton communities under increasing sea surface water temperatures.

Thesis: Ph. D., Joint Program in Oceanography/Applied Ocean Science and Engineering (Massachusetts Institute of Technology, Department of Biology; and the Woods Hole Oceanographic Institution), 2017. / Cataloged from PDF version of thesis. / Includes bibliographical references (pages 131-143). / Coral reefs are biodiverse ecosystems that are at risk of degradation as a result of environmental changes. Reefs are constantly in a state of flux: the resident species assemblages vary considerably in space and time. However, the drivers of this variability are poorly understood. Tracking these changes and studying how coral reefs respond to natural and anthropogenic disturbance can be challenging and costly, particularly for reefs that are located in remote areas. Because many reef animals produce and use sound, recording the ambient soundscape of a reef might be one way to efficiently study these habitats from afar. In this thesis, I develop and apply a suite of acoustics-based tools to characterize the biological and anthropogenic acoustic activity that largely comprises marine soundscapes. First, I investigate links between reef fauna and reef-specific acoustic signatures on coral reefs located in the U.S. Virgin Islands. Second, I compare those findings to a more expansive study that I conducted in Maui, Hawaii, in which the drivers of bioacoustic differences among reefs are explored. Third, I investigate the distances over which sounds of biological origin may travel away from the reef and consider the range within which these acoustic cues might be usable by pelagic larvae in search of a suitable adult habitat. Fourth, I assess the extent to which the presence of vessel noise in shallow-water habitats changes the ambient soundscape. Finally, I present the results of a modeling exercise that questions how ocean noise levels might change over the next two decades as a result of major projected increases in the number and size of and distance traveled by commercial ships. The acoustics-based tools presented here help provide insight into ecosystem function and the extent of human activity in a given habitat. Additionally, these tools can be used to inform an effective regulatory regime to improve coral reef ecosystem management. / by Maxwell Bernard Kaplan. / Ph. D.