Pagrindinis darbo tikslas- atlikti įstatymais nustatytų socialinių išmokų ir kompensacijų administravimo ir teikimo analizę Šilalės rajono savivaldybėje, įvertinti ir pateikti siūlymus dėl kompensacijų sistemos tobulinimo. Siekiant šio tikslo pirmiausiai aptarta Lietuvos socialinės paramos samprata, paramos poreikio atsiradimo priežastys, išanalizuoti ir susisteminti socialinės paramos ir pašalpų skyrimo principai, pateiktos piniginės socialinės paramos sistemos tobulinimo kryptys. Atlikta Lietuvos socialinės paramos šeimoms analizė. Patvirtinta suformuluota hipotezė, kad dabartinė pajamų kompensavimo sistema mažina darbo paskatas ir skatina žmones gyventi iš pašalpų. / The mani purpose-to carry out statutory social security benefits and compensation administration Šilalė analysis of the provision in the municipality to evaluate and provide suggestions for improving the system of compensation. To this end, in particular Lithuania discussed the concept of social support, the need to support causes, and to analyze the structure of social support and the award of grants provided financial support for improving the system of social trends. Analysis of the Lithuanian social analysis to support the family. Approved and formulated the hypothesis that the current system of income compensation reduces work incentives and encourage people to live on benefits.

Après une compétition, certains sportifs utilisent des stratégies pour accélérer la récupération des dommages musculaires. Le but général de cette thèse était d’étudier les effets de différentes stratégies sur les cinétiques de récupération après un exercice inducteur de dommages musculaires. Les objectifs des études réalisées étaient : 1) de comparer les effets du bain froid (10 minutes à 10°C) et de la cryothérapie corps entier (3 minutes à -110°C) sur la récupération ; 2) d’évaluer les effets d’une séance de musculation du haut du corps réalisée le lendemain d’un exercice des membres inférieurs sur leur récupération; 3) d’étudier les effets de la consommation d’un placebo en comparaison avec une condition contrôle sur les cinétiques de récupération. Le modèle expérimental utilisé pour induire des dommages musculaires dans ces trois études était un exercice constitué de 5 séries de 15 contractions excentriques maximales des fléchisseurs du genou. Cet exercice était caractérisé par une baisse de la fonction musculaire, une augmentation des concentrations sanguines en créatine kinase et une augmentation des douleurs musculaires. La fonction musculaire, des marqueurs perceptifs et sanguins des dommages musculaires étaient également évalués au cours des 72h suivant cet exercice. Dans la première étude, le bain froid permettait d’accélérer la récupération de la performance lors d’un saut en contre-mouvement sur une jambe et sur deux jambes 72h après l’exercice en comparaison avec la cryothérapie corps entier. Dans la deuxième étude, la musculation du haut du corps n’avait pas d’effet délétère sur la récupération et avait un effet bénéfique modéré sur la récupération de la force concentrique 48h après l’exercice. Dans la troisième étude, la consommation d’un placebo présentait une très forte probabilité d’avoir un effet bénéfique sur la performance en saut et les douleurs musculaires 72h après exercice. La perception de la récupération était également modérément améliorée 72h après exercice. En conclusion, les trois stratégies de récupération utilisées lors de ces études à savoir le bain froid, la séance de musculation et la consommation d’un placebo peuvent être efficaces après des exercices induisant des dommages musculaires. / Following competition, athletes commonly use strategies to accelerate their recovery from muscle damage. The overall objective of this thesis was to study the effects of different recovery strategies on recovery kinetics following exercise-induced muscle damage. The aims of the studies were as follows: 1) to compare the effects of cold-water immersion (10 minutes at 10°C) and whole-body cryotherapy (3 minutes at -110°C), 2) to assess the effects of an upper-limb strength training session, performed the day after a lower-limb exercise,, 3) to study the effects of a placebo ingestion in comparison with a passive recovery. The experimental model used to induce muscle damage in these three studies consisted of 5 sets x 15 repetitions of maximal eccentric contractions of the knee flexors muscles. This exercise resulted in a decrease of muscle function, increases in blood creatine kinase concentration as well as increases in perceived muscle soreness. Muscle function blood markers and subjective recovery from muscle damage were assessed throughout a 72h period post exercise. In the first study, cold-water immersion was more effective than whole-body cryotherapy evidenced through an accelerated recovery of both single and double leg countermovement jump 72h following exercise. In the second study, the upper-limb strength training session had a moderate beneficial effect on concentric force recovery 48h after the exercise and both interestingly and importantly, did not have any detrimental effect on recovery. Finally for the third study, placebo ingestion was ‘very likely’ to have a beneficial effect on jump performance and muscle soreness 72h post-exercise. Additionally, perceived recovery was moderately better 72h following exercise. In conclusion, the studies conducted in this thesis showed that the recovery strategies of cold-water immersion, strength training and ingestion of a placebo, may be effective after exercise-induced muscle damage.

L’objectif de cette thèse est d’apporter de nouvelles contraintes sur l’hydrologie de l’Atlantique Nord-Est et de la Méditerranée occidentale depuis la dernière période glaciaire à partir de l’analyse de la composition isotopique du Nd (εNd) dans des échantillons d’eau de mer ainsi que des coraux profonds et des foraminifères, prélevés dans des carottes sédimentaires marines. Les changements de l’hydrologie des masses d’eau intermédiaire (LIW, MSW, AAIW et masses d’eau intermédiaire des gyres subtropical et subpolaire) ont été plus particulièrement étudiés car leur rôle sur les transferts de sels en Atlantique Nord et in fine sur l’AMOC est actuellement mal contraint. Ce travail a été mené au cours des périodes de changements hydrologiques majeurs et abrupts de l’océan qui se sont produits lors des variations climatiques rapides de la dernière période glaciaire (événements d’Heinrich et cycles de Dansgaard-Oeschger) et lors du dépôt du Sapropel S1 en Méditerranée orientale. Dans un premier volet, nous avons amélioré la couverture spatiale des valeurs d’εNd des masses d’eau de l’Atlantique Nord-Est et de la mer d’Alboran, préalable indispensable pour restituer l’hydrologie passée de ces régions avec le traceur εNd. Nous avons ensuite mis en évidence un changement majeur du schéma de circulation de la Méditerranée occidentale durant la période de dépôt du sapropel S1, marquée par une forte réduction des masses d’eau de la Méditerranée orientale (LIW) au sud de la Sardaigne au profit de celles provenant du Golfe du Lion (WIW). Ce changement hydrologique ainsi que ceux qui s’opèrent en Méditerranée depuis la dernière période glaciaire ne sont pas associés à de fortes modifications des valeurs d’εNd de la LIW de la mer d’Alboran et de la mer des Baléares, suggérant une stabilité de la signature isotopique en Nd de la MOW au cours du temps. Ceci a permis, à partir d’un enregistrement d’εNd obtenus sur des coraux profonds du Golfe de Cadix, de mettre en évidence une contribution plus importante de l’AAIW plus radiogénique et donc une pénétration plus marquée en Atlantique Nord de cette masse d’eau lors des périodes de fortes réductions de l’AMOC, liées à la déstabilisation des calottes de glace de l’Hémisphère Nord. / : The purpose of this thesis is to constrain the hydrology of the North-East Atlantic and western Mediterranean Sea since the last glacial period from neodymium isotopic composition (εNd) measured on seawater, cold water corals and foraminifera. In particular, hydrological changes of intermediate water masses (LIW, AAIW, MSW, mid-subtropical and subpolar gyre water) have been studied as their role on salt budget in North Atlantic and ultimately on AMOC are currently poorly constrained. This work has been conducted at times of major and abrupt hydrological changes that occurred during rapid climatic variations of the last glacial period (Heinrich and Dansgaard-Oeschger events) and during the last sapropel deposit (S1) in eastern Mediterranean Sea. In a first step, we have improved the spatial distribution of water masses εNd values in North-east Atlantic and Alboran Sea, what is an absolute prerequisite in order to track past hydrological changes in these areas with εNd proxy. Next, we have highlighted a major change of the western Mediterranean circulation pattern during the sapropel S1 deposit, which is marked south of Sardinia by a strong reduction of eastern-sourced water masses (LIW) in favor of western-sourced water masses (WIW). This hydrological change as well as those occurring in Mediterranean Sea since the last glacial period was not associated with strong modifications of εNd values in Alboran and Balearic Sea, suggesting a stability of Nd isotopic signature of MOW over the time. This has highlighted, from an εNd record obtained on cold water corals in the Gulf of Cadiz, an enhanced contribution of more radiogenic AAIW and therefore a stronger northward penetration in North Atlantic at times of reduced AMOC linked to iceberg discharges from Northern Hemisphere ice sheets.

No description available.

Climate change is considered a major threat to freshwater ecosystems through altering biodiversity, structure, and function. Having a thorough understanding of how diverse ecosystems respond to temperature change is vital to ecosystem management and conservation. During summer 2012, I quantified fish biomass, somatic growth, secondary production, and habitat data for fish communities in 25 Appalachian streams from Vermont to North Carolina. Multiple statistical tests were conducted to determine the relationship between community fish production and air and water temperature, species thermal guild production and air and water temperature, and the relationship between community fish production and diversity. Community fish production estimates ranged from 0.15 to 6.79 g m-2 yr-1 and community P/B ratios ranged from 0.21 to 1.07. No significant differences existed between mean community production estimates at the cold-water, cool-water, warm-water, and extreme northern sites (P=0.19), but P/B ratios in the extreme northern streams were statistically higher than mean community P/B in cold- and cool-water streams in the southern Appalachians (P=0.002). Water temperatures had a positive effect on community fish production (P=0.01) while air temperatures did not (P=0.10). Both air and water temperatures were significant in predicting whether community production would be dominated by cold-water or cool-water fish (P=0.001, P<0.0001, respectively). Community fish production was significantly, positively related to species richness (R2=0.38, P=0.001) and was one of the highest correlates of community production (R2=0.52). As climate change alters freshwater ecosystems, fish communities may transform by means of shifting fish abundance, biomass, and production among species ultimately affecting ecosystem structure, function, and biodiversity. / Master of Science

Na presente dissertação eu estudei a distribuição potencial dos corais de águas profundas ao longo da margem continental brasileira e o efeito da resolução das variáveis ambientais em modelos de adequabilidade de habitat (MAH). Primeiramente foi determinada a distribuição potencial de corais de águas profundas a partir de modelos de adequabilidade de habitat de máxima entropia (MaxEnt). Os modelos foram alimentados com diversas camadas de dados SIG de variáveis ambientais e dados de ocorrência de espécies extraídos de bancos de dados e de novos registros. Foram estudados os grupos Scleractinia e Octocorallia, assim como quatro espécies de corais formadores de recifes (Solenosmilia variabilis, Lophelia pertusa, Madrepora oculata e Enallopsammia rostrata) e duas espécies de escleractínios não formadores de recifes (Cladocora debilis e Deltocyathus spp.). O nicho ambiental ocupado pelos táxons foi representado a partir de uma análise multivariada, sendo determinada a sobreposição entre os nichos. A partir disso foi avaliada a similaridade e equivalência de nicho ambiental entre as espécies. Os modelos resultantes indicaram que Scleractinia apresenta distribuição potencial na margem continental leste e sudeste do Brasil (porção Central e Sul), enquanto que Octocorallia apresenta uma distribuição potencial mais ampla abarcando toda a margem continental brasileira, com maior adequabilidade nas margens norte e nordeste. Assim, as áreas de distribuição potencial compartilhada entre octocorais e escleractínios foram aquelas ao largo da porção leste e sudeste do Brasil, sendo estas prioritárias para futuras pesquisas. Os nichos ambientais específicos indicaram menos tolerância de Scleractinia a altas temperaturas em comparação com Octocorallia. Os octocorais ocuparam uma maior amplitude do gradiente ambiental, principalmente relacionado às condições de carbono orgânico particulado, oxigênio dissolvido e temperatura. Isto possivelmente permite aos octocorais habitar a porção norte da margem continental brasileira, onde os modelos de escleractínios indicaram baixa adequabilidade de habitat. A margem continental sudeste do Brasil teve a maior adequabilidade para as espécies de escleractínios formadores de recifes profundos. Isto é de grande valor para planos de conservação nesta área que atualmente apresenta atividades de extração de óleo e gás e que, futuramente, pode ser explotada para a extração de minério. Além disso, as espécies formadoras de recifes ocuparam nichos ambientais similares e, portanto, mudanças nas condições ambientais, como por exemplo as associadas às mudanças climáticas, podem afetar todas elas. Contudo, seus nichos não são equivalentes e, portanto, cada uma delas faz um uso diferente do espaço ambiental da margem continental brasileira. Por último, foram desenvolvidos modelos MaxEnt para Solenosmilia variabilis, Lophelia pertusa, Madrepora oculata e Enallopsammia rostrata em duas resoluções de análise, uma de baixa (i.e., com um tamanho de pixel de aproximadamente 1000 m2) e uma de alta resolução (i.e., pixel de aproximadamente 100 m2) para determinar o efeito da resolução das variáveis ambientais utilizadas na performance e na extensão de área predita de modelos de adequabilidade de habitat. A diferença na extensão da área adequada predita por ambas resoluções foi medida de acordo a três limiares de corte diferentes. Os resultados indicaram diferenças na performance dependendo da resolução, com maior performance nos modelos de alta resolução. Além disso, a extensão de área adequada predita foi geralmente maior nos modelos de baixa resolução, com algumas exceções dependendo da espécie e do limiar de corte. Estes resultados ressaltam a importância da resolução das variáveis ambientais e suas implicações no uso de MAH no planejamento e manejo de Áreas Marinhas Protegidas (MPAs). / In this thesis I studied the deep-sea coral distribution along the Southwestern Atlantic Ocean and the effect of the environmental variables resolution on habitat suitability models (HSM). In the second chapter, I developed HSM based on the Maximum Entropy (MaxEnt) algorithm to identify the potential distribution of deep-water corals. To perform the models, I have used species presence data from existing datasets together with new species records and global environmental variables. I used the main environmental variables to identify suitable areas by modeling niches of different coral taxa. The studied taxa were Scleractinia and Octocorallia, as well as four reef-forming scleractinian species (Solenosmilia variabilis, Lophelia pertusa, Madrepora oculata and Enallopsammia rostrata), and two non-reef-building scleractinians (Cladocora debilis and Deltocyathus spp.). Furthermore, I used multivariate approach to compare their environmental occupied niche in order to assess the spatial niche overlap and test niche similarity and equivalence. The resulting cold-water coral models showed that the most suitable areas occur along the west and southwestern continental margin of Brazil, which permitted to determine areas of priority for future exploration/research to determine conservation areas. Specific environmental niches suggested lower tolerance to high temperatures for Scleractinia than for Octocorallia. Besides, octocorals occupied a wider range of the environmental gradient, which was mainly related to particulate organic carbon, oxygen and temperature. This probably enables them to inhabit the northern part of Brazil where scleratinian models classified as poor habitats for this group. In addition, the Southwestern Brazilian continental margin encloses the most suitable habitats for deep reef-building species. This has important implications for conservation plans in that area already facing gas and oil exploitation and probably future mineral extraction. On the other hand, results suggest that different scleractinian cold-water coral species occupy similar environmental niches and, for this reason, I concluded that changes in environmental conditions, such as those associated to climate change, may affect them all. However, their niches are not equivalent and this suggests that each environmental factor could affect each species in different ways. In the third chapter, I performed HSM based on Maximum Entropy for Solenosmilia variabilis, Lophelia pertusa, Madrepora oculata and Enallopsammia rostrata with two different environmental variables resolution, a low (i.e., a coarse resolution data with pixel size of ca. 1000 m2) and a high resolution (pixel of ca. 100 m2) to determine the effect of the environmental variables resolution on habitat suitability model performances and spatial extent of predicted suitable areas. From the final suitability maps, the changes in area extent depending of both resolution models were measured based in different thresholds. The results showed different performances of the models depending on data resolution, with higher performance at higher resolution. Furthermore, the predicted area varied between resolutions and threshold chosen. These results highlight the importance of environmental variables resolution and their implications for the use of HSM in planning and managing Marine Protected Areas (MPAs).

Na presente dissertação eu estudei a distribuição potencial dos corais de águas profundas ao longo da margem continental brasileira e o efeito da resolução das variáveis ambientais em modelos de adequabilidade de habitat (MAH). Primeiramente foi determinada a distribuição potencial de corais de águas profundas a partir de modelos de adequabilidade de habitat de máxima entropia (MaxEnt). Os modelos foram alimentados com diversas camadas de dados SIG de variáveis ambientais e dados de ocorrência de espécies extraídos de bancos de dados e de novos registros. Foram estudados os grupos Scleractinia e Octocorallia, assim como quatro espécies de corais formadores de recifes (Solenosmilia variabilis, Lophelia pertusa, Madrepora oculata e Enallopsammia rostrata) e duas espécies de escleractínios não formadores de recifes (Cladocora debilis e Deltocyathus spp.). O nicho ambiental ocupado pelos táxons foi representado a partir de uma análise multivariada, sendo determinada a sobreposição entre os nichos. A partir disso foi avaliada a similaridade e equivalência de nicho ambiental entre as espécies. Os modelos resultantes indicaram que Scleractinia apresenta distribuição potencial na margem continental leste e sudeste do Brasil (porção Central e Sul), enquanto que Octocorallia apresenta uma distribuição potencial mais ampla abarcando toda a margem continental brasileira, com maior adequabilidade nas margens norte e nordeste. Assim, as áreas de distribuição potencial compartilhada entre octocorais e escleractínios foram aquelas ao largo da porção leste e sudeste do Brasil, sendo estas prioritárias para futuras pesquisas. Os nichos ambientais específicos indicaram menos tolerância de Scleractinia a altas temperaturas em comparação com Octocorallia. Os octocorais ocuparam uma maior amplitude do gradiente ambiental, principalmente relacionado às condições de carbono orgânico particulado, oxigênio dissolvido e temperatura. Isto possivelmente permite aos octocorais habitar a porção norte da margem continental brasileira, onde os modelos de escleractínios indicaram baixa adequabilidade de habitat. A margem continental sudeste do Brasil teve a maior adequabilidade para as espécies de escleractínios formadores de recifes profundos. Isto é de grande valor para planos de conservação nesta área que atualmente apresenta atividades de extração de óleo e gás e que, futuramente, pode ser explotada para a extração de minério. Além disso, as espécies formadoras de recifes ocuparam nichos ambientais similares e, portanto, mudanças nas condições ambientais, como por exemplo as associadas às mudanças climáticas, podem afetar todas elas. Contudo, seus nichos não são equivalentes e, portanto, cada uma delas faz um uso diferente do espaço ambiental da margem continental brasileira. Por último, foram desenvolvidos modelos MaxEnt para Solenosmilia variabilis, Lophelia pertusa, Madrepora oculata e Enallopsammia rostrata em duas resoluções de análise, uma de baixa (i.e., com um tamanho de pixel de aproximadamente 1000 m2) e uma de alta resolução (i.e., pixel de aproximadamente 100 m2) para determinar o efeito da resolução das variáveis ambientais utilizadas na performance e na extensão de área predita de modelos de adequabilidade de habitat. A diferença na extensão da área adequada predita por ambas resoluções foi medida de acordo a três limiares de corte diferentes. Os resultados indicaram diferenças na performance dependendo da resolução, com maior performance nos modelos de alta resolução. Além disso, a extensão de área adequada predita foi geralmente maior nos modelos de baixa resolução, com algumas exceções dependendo da espécie e do limiar de corte. Estes resultados ressaltam a importância da resolução das variáveis ambientais e suas implicações no uso de MAH no planejamento e manejo de Áreas Marinhas Protegidas (MPAs). / In this thesis I studied the deep-sea coral distribution along the Southwestern Atlantic Ocean and the effect of the environmental variables resolution on habitat suitability models (HSM). In the second chapter, I developed HSM based on the Maximum Entropy (MaxEnt) algorithm to identify the potential distribution of deep-water corals. To perform the models, I have used species presence data from existing datasets together with new species records and global environmental variables. I used the main environmental variables to identify suitable areas by modeling niches of different coral taxa. The studied taxa were Scleractinia and Octocorallia, as well as four reef-forming scleractinian species (Solenosmilia variabilis, Lophelia pertusa, Madrepora oculata and Enallopsammia rostrata), and two non-reef-building scleractinians (Cladocora debilis and Deltocyathus spp.). Furthermore, I used multivariate approach to compare their environmental occupied niche in order to assess the spatial niche overlap and test niche similarity and equivalence. The resulting cold-water coral models showed that the most suitable areas occur along the west and southwestern continental margin of Brazil, which permitted to determine areas of priority for future exploration/research to determine conservation areas. Specific environmental niches suggested lower tolerance to high temperatures for Scleractinia than for Octocorallia. Besides, octocorals occupied a wider range of the environmental gradient, which was mainly related to particulate organic carbon, oxygen and temperature. This probably enables them to inhabit the northern part of Brazil where scleratinian models classified as poor habitats for this group. In addition, the Southwestern Brazilian continental margin encloses the most suitable habitats for deep reef-building species. This has important implications for conservation plans in that area already facing gas and oil exploitation and probably future mineral extraction. On the other hand, results suggest that different scleractinian cold-water coral species occupy similar environmental niches and, for this reason, I concluded that changes in environmental conditions, such as those associated to climate change, may affect them all. However, their niches are not equivalent and this suggests that each environmental factor could affect each species in different ways. In the third chapter, I performed HSM based on Maximum Entropy for Solenosmilia variabilis, Lophelia pertusa, Madrepora oculata and Enallopsammia rostrata with two different environmental variables resolution, a low (i.e., a coarse resolution data with pixel size of ca. 1000 m2) and a high resolution (pixel of ca. 100 m2) to determine the effect of the environmental variables resolution on habitat suitability model performances and spatial extent of predicted suitable areas. From the final suitability maps, the changes in area extent depending of both resolution models were measured based in different thresholds. The results showed different performances of the models depending on data resolution, with higher performance at higher resolution. Furthermore, the predicted area varied between resolutions and threshold chosen. These results highlight the importance of environmental variables resolution and their implications for the use of HSM in planning and managing Marine Protected Areas (MPAs).

Legionella pneumophila, the causative agent of Legionnaires' disease, is a water born pathogenic bacteria commonly found in natural and manmade water systems such as rivers, lakes, wet soil, hot and cold water storage systems (being able to survive at temperatures between 6-63 °C, and proliferating between 20-45 °C), showerheads, cooling towers and spa pools. The main pathway of exposure to Legionella is by inhaling the aerosols containing the microorganism. Legionnaires' disease can be fatal if not diagnosed and treated at the right time. Practical Legionella control starts with a risk assessment of the water system and followed by the regular monitoring and water sampling. UK Health and Safety Executive (HSE) have implemented strict legislations to protect the public from Legionnaires' disease. This research highlights and addresses three major data gaps identified in Legionella control and management strategy employed in the UK and worldwide; namely, (i) the underestimation of microbiological threat in current cold water storage sampling strategy, (ii) the inability of current qPCR diagnostic methods to detect live Legionella in water samples, and (iii) the lack of predictive 'risk management system' for Legionella control in domestic water systems. During my PhD, 15 relevant cold water storage tanks (selected from more than 6000 tanks surveyed at different sites located in different London Boroughs) were used to investigate the risk factors that contribute towards Legionella proliferation, and revealed serious shortcomings in the appropriateness of the water sample taken for regulatory testing. Secondly, molecular biology research was carried out to develop an accurate, reliable and rapid testing method for the detection and quantification of live Legionella using qPCR techniques. This was successfully achieved by extracting RNA from a Legionella lenticule, converting the RNA into cDNA and amplifying the cDNA using qPCR techniques. Finally, regular monitoring data from 120 London buildings (60 known to be Legionella positive and 60 known to be Legionella negative) was used to identify the possible risk factors contributing towards Legionella outbreaks. Data for these factors was then used to develop a predictive risk model for Legionella contamination using Principal Component Analysis (PCA). The model was validated with 66 new London buildings and 9 out of London buildings. The model showed 100% accuracy in predicting the risk of Legionella by distinguishing infected and non-infected sites in London as well as for the sites in out of London.

L’influence de la diversité génétique sur la stabilité démographique des populations constitue un paradigme de l’écologie évolutive. Au sein des populations naturelles, l’étude de cette relation est complexifiée par l’influence réciproque de la stabilité sur la diversité, et leur degré d’interconnexion. Ces interrelations ont été explorées chez la plante marine Zostera marina et les coraux d’eau froide Lophelia pertusa et Madrepora oculata, des espèces partiellement clonales. Ce trait d’histoire de vie, influençant profondément la dynamique démographique et la trajectoire évolutive des espèces, a constitué le fil d’Ariane de ce travail. L’échantillonnage dans l’espace (échelle régionale) et le temps (un pas de trois ans) d’herbiers de Zostère a permis de mieux comprendre la dynamique clonale de ces plantes. L’architecture et la diversité clonale apparaissent comme la résultante de l’équilibre entre dispersion/recrutement de nuages de graines dispersées collectivement, et la compétition pour l’espace entre clones. Les perturbations affectent localement l’équilibre de l’herbier. Cette dynamique originale rend impossible l’identification des contours populationnels. En revanche, nos résultats semblent indiquer que la diversité génétique au sens strict (hétérozygotie et nombre d’allèles) des herbiers de Zostères constitue un facteur de stabilité démographique, via sa potentielle influence sur les capacités de résistance aux perturbations saisonnières. Les coraux d’eau froide, quant à eux, présentent des patrons biogéographiques en accord avec l’hypothèse d’une extinction dans le Golfe de Gascogne, lors des derniers épisodes glaciaires. Les marques visibles des activités de pêche posent la question des capacités de résilience de ces écosystèmes, qui dépendent entre autres du potentiel de dispersion de ces espèces. L’absence de structure génétique observée chez L. pertusa suggère, au moins pour cette espèce, un fort degré d’interconnexion entre les récifs, tandis que M. oculata montre davantage de structure régionale. La sensibilité de ces espèces aux variations climatiques et à la pression des activités anthropiques souligne la nécessité d’études approfondies, pour leur conservation.Les résultats obtenus pendant cette thèse permettent de mieux comprendre la dynamique populationnelle des herbiers et récifs profonds, le taux de clonalité et la connectivité des populations. Ces informations sont essentielles pour avancer vers une meilleure compréhension de la dynamique et la résistance de ces espèces structurantes, et sont donc primordiales pour la conservation de ces écosystèmes clé. / The influence of genetic diversity on the demographic stability of populations constitutes a paradigm in evolutionary ecology. The complexity of this relationship within natural populations is enhanced by the reciprocal effect of stability on diversity, and the degree of interconnection among populations. This interaction was explored within the seagrass Zostera marina and the cold-water corals Lophelia pertusa and Madrepora oculata, three partially clonal species. This life history trait, deeply influencing the population dynamics and evolutionary trajectory of species, constituted the underlying theme of this work.The sampling in space (regional scale) and time (a three-years step) of eelgrass meadows allowed us to better understand the clonal dynamics of these plants. The clonal architecture and diversity may result from the equilibrium between dispersal/recruitment of collectively dispersed clouds of seeds, and the competition for space among clones. Perturbations locally affect the equilibrium of meadows. This original dynamic makes impossible the identification of population contours. Yet, our results suggest that the genetic diversity sensu stricto (heterozygosity and number of alleles) represents a factor of demographic stability, through its putative influence on resistance capacity for seasonal disturbances. Cold-water corals show biogeographic pattern in line with the hypothesis of glacial extinction, within the Bay of Biscay. The noticeable footprints of fishing activities question the capacity of resilience of these ecosystems, depending on dispersal potential of the structuring species, which showed low levels of clonality. The lack of genetic structure observed for L. pertusa suggest, at least for this species, a high degree of interconnection among reefs at large scale, while M. oculata revealed a stronger regional structure. Sensitivity of these two species to climatic variations and the pressures of human activities highlight the need of thorough studies for their conservation. Results obtained during this thesis allow a better understanding of the populations dynamics of both seagrass and deep reefs and their levels of clonality and connectivity. This information constitutes the first step toward a better understanding of dynamics and resistance of these structuring species, and is also primordial for the conservation of their key ecosystems.

One of the ocean’s greatest resources is the coral reefs, providing unique habitats for alarge variety of organisms. During drilling operations offshore many activities maypotentially harm these sensitive habitats. Det Norske Veritas (DNV) has developed arisk-based approach for planning of drilling operations called Coral Risk Assessment (CRA) to reduce the risk of negative effects upon cold water corals (Lophelia pertusa) on the Norwegian Continental Shelf (NCS). In order to get a good risk assessment amodelled dispersion plume of the drilling discharges is recommended. This study concerned a drilling case at the Pumbaa field (NOCS 6407/12-2) on the NCS, and used two different dispersion models, the DREAM model and the MUDFATE model in order to investigate how to perform good risk assessments. In the drill planning process a decision to move the discharge location 300 m north-west from the actual drilling location and reducing the amount of drilling discharges, was made inorder to reduce the risk for the coral targets in the area. The CRA analysis indicated that these decisions minimised the risk for the corals, and showed that the environmentalactions in the drill planning processes are necessary in order to reduce the risk for the coral targets and that the analysis method is a preferable tool to use. The amount of discharges, the ocean current data, the discharge location and the condition of the coral targets are the factors having the most important impact on the CRA results. From monitoring analysis from the case of study, it can be seen that a pile builds up around the discharge location. The dispersion models do not seem to take into account this build-up of a pile and thereby overestimate the dispersion of drilling discharges. This observation was done when modelled barite deposit was compared with barium concentrations measured in the sediment after the drilling operation. The overestimationis the case for the DREAM model, but has not been seen in the simulations with the MUDFATE model. Results from the modelling also indicated a higher overestimation for the DREAM model when using a cutting transport system (CTS) to release thedrilling discharges compared to release the discharges without using the CTS. / Korallrev består av ett skelett av kalciumkarbonat som bygger upp unika habitat på havsbotten. Dessa utnyttjas av flera olika organismer och är en av havets största och viktigaste resurser. Under prospekteringsborrningar till havs sker stora mängder utsläpp som kan påverka de känsliga miljöerna negativt. Det Norske Veritas (DNV) har utvecklat en riskbaserad strategi för planering av prospekteringsborrning i områden med koraller kallad Coral Risk Assessment (CRA). I CRA-analysen utvärderas risken för korallstrukturer (Lophelia pertusa) att påverkas av olika borrningsaktiviteter. Spridningsmodellering av det förväntade utsläppet från borrningsoperationen är ett viktigt hjälpmedel för att kunna utföra riskanalysen på ett tillfredsställande sätt. Studien har studerat en tidigare utförd prospekteringsborrning på Pumbaa-fältet (NOCS 6407/12-2) på den norska kontinentalsockeln och två olika spridningsmodeller DREAM och MUDFATE har jämförts i studien med syfte att förbättre riskbedömningen. I planeringsstadiet av prospekteringsborrningen togs ett beslut att flytta utsläppspunkten för det producerade borrslammet 300 m nordväst från brunnen samt att mängden borrslam skulle reduceras för att minska risken för påverkan på korallstrukturerna i området. CRA-analysen som utfördes i denna studie visade att dessa beslut minskat risken för korallstrukturerna att bli påverkade. Detta indikerar således att analysmetoden är ett viktigt verktyg att använda vid miljöundersökningar i planeringsstadiet för att minska risken för oönskad påverkan från aktiviteter i samband med prospekteringsborrning. De faktorer som har störst påverkan på CRA-analysen är mängden borrslam, strömdata, utsläppspunkt och tillståndet på korallstrukturerna. Under miljöövervakningen i samband med borrningsprocessen påvisades det att vallar av borrslam byggdes upp nära utsläppspunkten, vilket skedde relativt snabbt efter det att utsläppet startat. Spridningsmodellerna verkar inte ta hänsyn till denna uppbyggnad utan överestimerar spridningen och depositionen av borrslam. Detta har påvisats vid jämförelser av modellerade och uppmätta värden av bariumkoncentrationer i sedimentet. Överestimeringen är påvisad för DREAM, men slutsatsen är mer osäker för MUDFATE. Spridningsmodelleringen med DREAM indikerar även en större överestimering av resultaten om utsläppen sker med en så kallad CTS (Cutting Transport System).