Changes in climate and land use interact in a complex system with various feedbacks including water, carbon (C), and nitrogen (N) fluxes. In this dissertation, firstly measurements of surface fluxes were conducted via two different measurement systems, a Bowen Ratio (BR) and an Eddy Covariance (EC) system. Over two succeeding years, fluxes and gradients of heat, water vapour, and CO2 over winter barley and rapeseed were simultaneously measured at Klingenberg, a long-term cropland site in eastern Germany. The two independent systems (EC/BR) are compared with respect to energy and CO2 fluxes. Inspection as well as a neutral regression analysis show that differences between the systems were largest for latent heat LE. EC detects apparently lower LE due to the lack of closure of the energy balance of approximately 30%, whereas the fluxes of CO2 show only smaller differences up to 10%. Therefore, Bowen Ratio setups remain an alternative to EC systems when gradients are large and analysers with high measurement frequency are not available. Encouraged by this analysis, the Modified Bowen Ratio system was used to measure the vertical gradients of mixing ratios of nitrogen oxides (NOx) and ammonia (NH3). Fluxes of these nitrogen species are analysed and associated to the corresponding growth status of two crops within two growing periods. Integration of these nitrogen fluxes results in a net emission into the atmosphere of 1.25 kg N ha-1 for the total measurement period of 77 days, differing in the proportion of NOx and NH3. However, this net emission does not largely reduce the fertilization of the crop site. In a second step, the atmospheric boundary layer model HIRVAC (HIgh Resolution Vegetation Atmosphere Coupler) was improved and applied to three different land uses within the TU-Dresden-cluster for selected time periods in 2009 and 2010. Simulated fluxes of H2O and CO2 with the improved model HIRVAC show good agreement with measurements. Realistic fluxes were obtained with respect to the diurnal cycle as well as the order of magnitude. Modelling of energy and trace gas fluxes also gives the opportunity to assess effects of changing climate conditions on surface fluxes. Since in the improved HIRVAC version a coupled model for stomatal conductance is used, an increase in CO2 concentration is linked with a decrease of stomatal conductance in the simulation. Therefore, simulations of changes in climate condition along with elevated CO2 concentrations and their effect on latent heat fluxes are analysed. The grassland and agricultural site revealed increased evapotranspiration with elevated temperatures and CO2 concentrations, whereas the forest site came up with reduced evapotranspiration rates. Concerning the flux of CO2, all land uses considered here increased the amount of assimilated carbon, whereby the forest site increased the most. Finally, the scenario calculations revealed that regarding evapotranspiration and CO2, differences of land use dominate over differences of climate change. / Veränderungen des Klimas und von Landnutzungen wirken sich in einem komplexen System mit diversen Rückkopplungen auf die Wasser-, Kohlenstoff- und Stickstoffflüsse aus. In dieser Dissertation wurden zuerst Flüsse mit zwei unterschiedlichen Methoden erfasst, einem Bowen-Ratio (BR) und einem Eddy-Kovarianz (EC) System. Dafür wurden für zwei aufeinanderfolgende Jahre Gradienten bzw. Flüsse von Wärme, Wasserdampf und CO2 über Wintergerste und Raps an einem langjährigen Agrarstandort im Osten Deutschlands (Station Klingenberg) gemessen. Die zwei unabhängigen Messmethoden (EC/BR) werden in dieser Arbeit in Bezug auf die Energie- und CO2-Flüsse miteinander verglichen. Die genaue Analyse dieser Flüsse ergibt, dass die größten Unterschiede zwischen den Messmethoden im latenten Wärmefluss (LE) vorzufinden sind. Bedingt durch die Schließungslücke von ungefähr 30 % ergibt die EC-Methode einen geringeren latenten Wärmefluss, wohingegen die Flüsse von CO2 nur Unterschiede um 10 % aufweisen. Wie der Vergleich zeigt, ist die Bowen-Ratio-Messmethode besonders dann eine wertvolle Alternative zu EC-Systemen, wenn die Gradienten der gemessenen Komponenten groß sind oder wenn Analysatoren mit hoher Messfrequenz nicht verfügbar sind. Bestärkt durch diese Ergebnisse, wurde das modifizierte Bowen-Ratio-System (MBR) verwendet, um vertikale Gradienten der Mischungsverhältnisse von Stickoxiden (NOx) und Ammoniak (NH3) zu messen. Die ermittelten Flüsse dieser Stickstoffkomponenten werden mit den Entwicklungsstadien der jeweiligen Feldfrüchte innerhalb zweier Anbauperioden in Verbindung gebracht. Die Summe der gemessenen Stickstoffflüsse ergibt eine Nettoemission in die Atmosphäre von 1,25 kg N ha-1 über die gesamte Messperiode von 77 Tagen (mit unterschiedlichen Anteilen von NOx und NH3), wobei diese Emission die Düngung der Agrarfläche nur geringfügig reduziert. Diese Ergebnisse stehen im Einklang mit Messergebnissen an anderen Agrarstandorten. Im zweiten Teil wurde das atmosphärische Grenzschichtmodell HIRVAC (HIgh Resolution Vegetation Atmosphere Coupler) überarbeitet und für drei unterschiedliche Landnutzungen innerhalb des TU-Dresden-Clusters für ausgewählte Zeitscheiben der Jahre 2009 und 2010 angewandt. Die mit dem Modell HIRVAC simulierten Flüsse von Wasser und CO2 zeigen eine gute Übereinstimmung mit den Messungen. Bezüglich des Tagesganges sowie auch in ihrer jeweiligen Größenordung wurden realistische Flüsse berechnet. Die Modellierung der Energie- und Spurengasflüsse bietet außerdem die Möglichkeit, Auswirkungen von veränderlichen klimatischen Bedingungen auf die turbulenten Flüsse zu bewerten. Da in der verbesserten HIRVAC-Version ein gekoppeltes Modell für die stomatäre Leitfähigkeit verwendet wird, ist nun innerhalb der Simulation ein Anstieg der CO2-Konzentration mit einem Rückgang der stomatären Leitfähigkeit verknüpft. Somit können Szenariosimulationen von veränderlichen Klimabedingungen zusammen mit erhöhten CO2-Konzentrationen und deren Auswirkungen auf die latenten Wärmeflüsse analysiert werden. Die Grünland- sowie auch die Agrarfläche zeigen verstärkte Evapotranspirationsraten unter erhöhten Temperatur- und CO2-Bedingungen, wohingegen der Waldstandort verminderte Evapotranspirationsraten zeigt. Hinsichtlich des CO2-Flusses reagieren alle drei berücksichtigten Landnutzungen mit erhöhten Aufnahmeraten von Kohlenstoff, wobei der Waldstandort den höchsten Anstieg aufweist. Schlussendlich ergaben die Szenariosimulationen bezüglich Evapotranspiration und CO2, dass die Unterschiede zwischen den Landnutzungen gegenüber denen des prognostizierten Klimawandels überwiegen.

Exocyst is a protein complex composed of eight subunits, evolutionarily conserved in yeasts, animals, and plants. The main function of exocyst is to mediate the tethering of secretory vesicles to the plasma membrane. However, the involvement of exocyst in some other processes, especially in autophagy, has been recently discovered. Plant exocyst is specific because most of its subunits have multiple paralogs. The most diversified subunit is EXO70, which is encoded by 23 paralogous genes in Arabidopsis thaliana. In this thesis, I dealt with subunit AtEXO70E2 (AT5G61010), which has been localized to double-membrane compartments considerably reminiscent of autophagosomes. These compartments were named EXPOs (for exocyst-positive organelles) and described as a component of unconventional protein secretion pathways. There are also hints that EXO70E2 could play a role in autophagic processes. However, details of this relationship remained unexplored. For my experiments, I used stably transformed lines of A. thaliana and transiently transformed leaves of Nicotiana benthamiana. I performed numerous colocalization experiments, applied various pharmacological treatments to the studied lines, and analyzed a mutant line in the EXO70E2 gene. According to my observations, protein EXO70E2 is expressed especially...

Litter decomposition is a key process for carbon and nutrient cycling in terrestrial ecosystems and is mainly controlled by environmental conditions, substrate quantity and quality as well as microbial community abundance and composition. In particular, the effects of climate and atmospheric nitrogen (N) deposition on litter decomposition and its temporal dynamics are of significant importance, since their effects might change over the course of the decomposition process. Within the TeaComposition initiative, we incubated Green and Rooibos teas at 524 sites across nine biomes. We assessed how macroclimate and atmospheric inorganic N deposition under current and predicted scenarios (RCP 2.6, RCP 8.5) might affect litter mass loss measured after 3 and 12 months. Our study shows that the early to mid-term mass loss at the global scale was affected predominantly by litter quality (explaining 73% and 62% of the total variance after 3 and 12 months, respectively) followed by climate and N deposition. The effects of climate were not litter-specific and became increasingly significant as decomposition progressed, with MAP explaining 2% and MAT 4% of the variation after 12 months of incubation. The effect of N deposition was litter-specific, and significant only for 12-month decomposition of Rooibos tea at the global scale. However, in the temperate biome where atmospheric N deposition rates are relatively high, the 12- month mass loss of Green and Rooibos teas decreased significantly with increasing N deposition, explaining 9.5% and 1.1% of the variance, respectively. The expected changes in macroclimate and N deposition at the global scale by the end of this century are estimated to increase the 12-month mass loss of easily decomposable litter by 1.1– 3.5% and of the more stable substrates by 3.8–10.6%, relative to current mass loss. In contrast, expected changes in atmospheric N deposition will decrease the mid-term mass loss of high-quality litter by 1.4–2.2% and that of low-quality litter by 0.9–1.5% in the temperate biome. Our results suggest that projected increases in N deposition may have the capacity to dampen the climate-driven increases in litter decomposition depending on the biome and decomposition stage of substrate.

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No description available.

The history of death is entangled with the history of changing social values, meaning that a shift in attitudes to death will be consistent with changes in a society’s world view. Late Mesolithic shell middens in the Tagus and Sado valleys, Portugal, constitute some of the largest and earliest burial grounds known, arranged and maintained by people with a hunting, fishing, and foraging lifestyle, c 6000–5000 cal BCE. These sites have been interpreted in the light of economic and environmental processes as territorial claims to establish control over limited resources. This approach does not explain the significance of the frequent disposal of the dead in neighbouring burial grounds, and how these places were meaningful and socially recognized. The aim of this dissertation is to answer these questions through the detailed analysis of museum collections of human burials from these sites, excavated between the late nineteenth century and the 1960s. I examine the burial activity of the last hunter-gatherers of the south-western Iberian Peninsula from an archaeological perspective, and explain the burial phenomenon through the lens of historical and humanist approaches to death and hunter-gatherers, on the basis of theoretical concepts of social memory, place, mortuary ritual practice, and historical processes. Human burials are investigated in terms of time and practice based on the application of three methods: radiocarbon dating and Bayesian analysis to define the chronological framework of the burial activity at each site and valley; stable isotope analysis of carbon and nitrogen aimed at defining the burial populations by the identification of dietary choices; and archaeothanatology to reconstruct and define central practices in the treatment of the dead. This dissertation provides new perspectives on the role and relevance of the shell middens in the Tagus and Sado valleys. Hunter-gatherers frequenting these sites were bound by shared social practices, which included the formation and maintenance of burial grounds, as a primary means of history making. Death rituals played a central role in the life of these hunter-gatherers in developing a sense of community, as well as maintaining social ties in both life and death.

A mesocosm experiment was carried out in a Norwegian fjord near Bergen in May 2006, with the main objective being the study of the effects of increasing concentrations of atmospheric CO2 (and associated effects such as increased acidification) on blooms of natural marine coastal plankton. Three mesocosms were bubbled with CO2(g) to achieve a high (~700ppm) CO2 concentration (pH ~7.8) to simulate predicted future conditions as a result of rising atmospheric CO2 concentrations. Another three mesocosms were treated as controls and bubbled with ambient air to represent a near pre-industrial scenario (atmospheric CO2 concentration ~300ppm, surface seawater pH ~8.15). Blooms in the mesocosms were stimulated by the addition of nutrients at a near-Redfield ratio ([N:P] ≈ [16:1]), and scientific measurements and analyses were carried out over the course of the blooms for approximately one month. Of particular interest in this study were the autotrophic plankton. The diversity and activities of these microorganisms under the two treatments was therefore investigated. By designing and using new degenerate primers specifically targeting ‘Green-type’ (Form IA and IB), ‘Red-type’ (Form IC and ID) and Form II RuBisCO, analysis of primary producers was carried out using PCR and either gDNA or cDNA (mRNA) templates from key time points spanning the complete duration of the blooms throughout the mesocosm experiment. Over 1250 novel RuBisCO large subunit sequences have been fully annotated and deposited in the NCBI GenBank® database. These sequences revealed distinct changes in the diversity of primary producers both over the courses of the blooms and between treatments. Particularly striking was the effect of acidification on the community structure of the eukaryotic picoplankton, Prasinophytes. A clade of prasinophytes closely related to Micromonas pusilla showed a distinct preference for the high CO2 conditions; a laboratory-based experiment confirmed the high tolerance of Micromonas pusilla to lower pH. Conversely, a clade related to Bathycoccus prasinos was almost entirely excluded from the high CO2 treatments. Clades of form II RuBisCO-containing dinoflagellates were also abundant throughout the experiment in both treatments. The high similarity of some of these clades to the toxin-producing species Heterocapsa triquetra and Gonyaulax polyedra, and apparent high tolerance of some clades to high CO2 conditions, is perhaps cause for concern in a high CO2 world and demands further research. In parallel with the RubisCO work, new primers were designed that target the gene encoding the Fe protein of nitrogenase (NifH). 82 Bergen genomic nifH sequences have been annotated and submitted to GenBank®. These sequences include those from organisms related to Alpha, Beta, and Gammaproteobacteria, and Cluster II and Cluster III sequences that align most closely with anaerobic Bacteria, Gram positive, and/or sulphur-reducing Bacteria. The biggest surprise, however, was the apparent abundance and significance of a Rhodobacter sphaeroides-like microorganism throughout the duration of the experiment in both treatments. Whilst this clade was unsurprisingly absent in the RuBisCO cDNA libraries, all but two of 128 nifH cDNA clones analysed were identical to the gene from Rhodobacter sphaeroides. This shows that this clade was potentially fixing N2 throughout the entire experiment, even in the presence of combined N added to both sets of mesocosms at the start of the experiment. A group of Rhodobacter sphaeroides-like microorganisms present at Bergen may therefore have been an unexpected source of new N during the experiment and contributed to the maintenance of the mesocosm communities as nutrients became depleted. One organism dominated the autotrophic communities after the blooms in both treatments. Synechococcus spp. Form IA rbcL clones most closely related to the coastal strain Synechococcus sp. strain CC9902 were recovered throughout the experiment but were particularly numerous toward the end of the experiment and dominated the “Green-type” libraries at this time. Initially, rbcL clones from these cyanobacteria were mostly derived from the ambient CO2 mesocosms but were equally distributed between treatments by the end of the experiment. This suggests that cyanobacteria related to strain CC9902 may be less tolerant of elevated CO2 (which was greatest at the beginning rather than the end of the experiment). However, despite the mesocosms being Pi-limited at the end of the experiment, several Synechococcus species (including those related to strain CC9902 and another coastal strain, CC9311) thrived. Following on from this observation, Pi uptake and assimilation mechanisms in a Synechococcus species were investigated in the laboratory. This led to the sequencing and characterisation of a pstS gene from the marine cyanobacterium Synechococcus sp. WH 8103. Unlike conventional pstS, it was discovered that the pstS II gene in this organism is constitutively expressed and unresponsive to or only weakly regulated by Pi supply. The use of PstS/pstS as a marker for P-limitation in natural samples, therefore, should be interpreted with caution.

Ce projet de recherche porte principalement sur la reconstruction du régime alimentaire à l’aide d’une approche paléochimique. Des analyses isotopiques du carbone de l’azote ont été réalisées sur le collagène des os sur un échantillon de trente-huit individus provenant de trois sites différents de la basse vallée de Santa, sur la côte nord du Pérou : El Castillo, Guadalupito et Huaca China. Parmi les individus sélectionnés, certains sont affiliés aux groupes des Gallinazo, des Mochica, des Tanguche ou des Chimú couvrant ainsi la Période intermédiaire ancienne, l’Horizon moyen et la Période intermédiaire récente. L’approche isotopique a été utilisée afin de caractériser dans un premier temps, le régime alimentaire de la population globale en la comparant à d’autres groupes préhispaniques de l’Aire andine. Les résultats obtenus sur trente-deux individus suggèrent une alimentation variée incluant le maïs ainsi que des ressources marines, illustrant que ces groupes agriculteurs exploitaient les deux types d’écosystèmes à leur portée. Ces résultats sont supportés par l’analyse du carbone sur l’apatite pour cinq individus. Le second but fut d’étudier la variabilité du régime alimentaire entre les différents individus de l’échantillon, en fonction de la période d’occupation, du site de provenance, de l’affiliation culturelle, de l’âge et du sexe et du statut social. La petite taille de l’échantillon a limité considérablement la discussion de ces différents paramètres. Il a toutefois été possible de remarquer un accès aux ressources riches en protéines plus avantageux pour les hommes et la présence de possibles différences dans l’alimentation chez les individus juvéniles. Finalement, la confrontation des données funéraires à la reconstruction du régime alimentaire a été faite pour cinq cas particuliers de pratiques funéraires provenant du site El Castillo, premier centre régional de la civilisation Mochica dans la basse vallée de Santa. Dans tous les cas, le régime alimentaire suggéré par les compositions isotopiques supporte les interprétations des statuts sociaux de ces individus faites à partir des contextes funéraires. / This research focuses on the reconstruction of diet using a chemical approach. Carbon and nitrogen isotopes were analyzed on a bone collagen sample of thirty-eight individuals from three different sites of the Lower Santa valley, on the north coast of Peru : El Castillo, Guadalupito and Huaca China. Among those individuals selected, some are affiliated with groups of Gallinazo, Moche, Tanguche and Chimu, dated to the Ancient Intermediate Period, Middle Horizon and Recent Intermediate Period. The isotopic approach has been used to characterize in a first step, the diet of the entire population by comparing with some other prehispanic groups from the Andean area. The results of thirty-two individuals suggest a mixed diet including maize and marines resources, showing that these agriculturist groups exploited their surrounding ecosystems. These results are supported by the carbon analysis on bone apatite for five individuals. The second aim was to study the variability of the diet between individuals in the sample, depending on the time period, site, cultural identity, age and sex and social status. The small sample size has considerably limited the discussion of these parameters. However, it was possible to note a more preferential access to high proteins resources for men and some possible differences in diet among juveniles. Finally, the comparison between dietary reconstruction and funerary patterns was made for five cases of burial pratices at El Castillo site, the first Moche regional center in the Lower Santa valley. In all cases, diet suggested by isotopic compositions is consistent with interpretations of the funerary context about the individual status.

Les communautés microbiennes du sol peuvent améliorer la croissance de la plante en augmentant la disponibilité en nutriments du sol, favorisant ainsi leur prélèvement par la plante. Dans le contexte d’une production agricole à bas niveau d’intrants, la nutrition de la plante est susceptible de reposer de plus en plus sur les interactions plante-communautés microbiennes de la rhizosphère, qui peuvent être modulées par le génotype de la plante. Pourtant, très peu d’études se sont intéressées aux modifications des communautés microbiennes de la rhizosphère dans leur globalité et ce en relation avec à la fois le génotype et le phénotype de la plante. Ces travaux de thèse ont été consacrés à étudier l’effet du génotype de la plante sur la structure génétique des communautés microbiennes de la rhizosphère en relation avec les stratégies nutritionnelles de la plante.L’interaction plante-communautés microbiennes de la rhizosphère a été évaluée par une approche multidisciplinaire alliant écophysiologie et écologie microbienne. L’effet du génotype de la plante sur la structure génétique des communautés microbiennes de la rhizosphère qui lui sont associées a été analysé par DNA fingerprint. Les différentes stratégies nutritionnelles de la plante ont été analysées par une approche de type structure/fonction prenant en compte la mise en place des structures (feuilles, racines) et leur fonctionnement (photosynthèse, rhizodéposition, prélèvement spécifique d’azote).Dans une première expérimentation réalisée sur sept génotypes de Medicago truncatula, nous avons montré qu’à un stade précoce du développement de la plante, le génotype de Medicago truncatula affectait la structure génétique des communautés bactériennes du sol. En revanche, à ce stade précoce, peu de différences de croissance ont été observées entre les différents génotypes étudiés. Ces derniers ont par contre présenté des stratégies nutritionnelles contrastées. Les descripteurs fonctionnels sont donc plus efficaces que les descripteurs structurels pour discriminer les génotypes de plantes à un stade précoce du développement de la plante. De plus, nous avons montré un lien entre les stratégies nutritionnelles de la plante et la sélection des communautés bactériennes associées. Cette étude nous a également permis de développer un cadre d’analyse écophysiologique appliqué à l’étude des interactions plante-communautés microbiennes de la rhizosphère.Outre l’effet majeur du génotype de la plante dans les interactions plante-communautés bactériennes de la rhizosphère, nous avons également montré qu’il y avait un effet important de l’environnement, comme la disponibilité en azote minéral du sol. En effet, la disponibilité en azote minéral du sol a affecté la structure génétique des communautés bactériennes rhizosphériques via un effet indirect de la plante dépendant du génotype considéré. Les effets des différents génotypes de Medicago truncatula et de leurs stratégies de réponses à des contraintes environnementales, comme la disponibilité de l’azote du sol, se sont révélées être des composantes majeures de la sélection des communautés microbiennes. [...] / The soil microbial communities can improve plant growth by increasing soil nutrient availability, thereby promoting their uptake by the plant. In an overall context of input reduction, the plant nutrition should be increasingly based on plant- rhizosphere microbial communities’ interactions. Yet, very few studies have examined the entire rhizosphere microbial communities in relationship with both plant genotype and phenotype. The aim of this thesis was to study the plant genotype effect on the rhizosphere microbial communities in relationship with the plant nutritional strategies.To do so, the plant-rhizosphere microbial communities’ interaction was assessed by a multidisciplinary approach combining ecophysiology and microbial ecology. The plant genotype effect on the genetic structure of the associated rhizosphere microbial communities was analyzed by DNA fingerprinting. The different plant nutritional strategies were analyzed by a structural/functional approach taking into account both structure establishment e.g. leaves and functions e.g. photosynthesis.In a first experiment carried out on seven genotypes of Medicago truncatula, we showed that the Medicago truncatula genotype affected the genetic structure of the rhizosphere bacterial communities very early relatively to the plant development stages. However, at this early stage, few growth differences could be observed among the different genotypes. Yet, those genotypes presented contrasted nutritional strategies. Therefore, the functional descriptors were more efficient than the structural ones to discriminate plant genotypes at an early developmental stage. In addition, we showed that a link existed between the plant nutritional strategies and the rhizosphere bacterial communities selection. Finally, this study enabled to develop a multidisciplinary framework applied to the study of the plant- rhizosphere microbial communities’ interactions.In addition to the plant genotype effect, we showed that there is an environmental effect e.g. soil mineral nitrogen availability on the rhizosphere bacterial communities. Indeed, the soil mineral nitrogen availability affected the genetic structure of the rhizosphere bacterial communities via an indirect effect of the plant depending on its genotype. The effects of the different Medicago truncatula genotypes and their response strategies to environmental constraints (soil mineral nitrogen availability), proved to be a major component of the selection of the rhizosphere microbial communities.In order to identify the genetic determinisms of the interaction between the plant and the rhizosphere microbial communities, a second experiment was conducted on a core collection of 184 genotypes of Medicago truncatula. Initial results enabled to identify and characterize four groups of genotypes with contrasted phenotypes for their growth and their specific nitrogen uptake. Thanks to high-throughput sequencing, we will analyze the rhizosphere microbial communities’ diversity associated with the different Medicago truncatula genotypes. These results should determine if the plant genotype influences the selection of beneficial rhizosphere microbial communities. Moreover, when the whole genome sequencing data would be available for the 184 genotypes of the Medicago truncatula core collection, a genome-wide association study will be proceed. The creation of plant ideotypes, which will promote beneficial interactions with rhizosphere microbial communities, will be possible. Plant growth and yield will be improved without the concomitant increase of agricultural inputs.

A região costeira do Brasil é historicamente impactada por atividades antrópicas, que liberam contaminantes, como os metais pesados. Nos estuários de Paranaguá (PR), Cananéia e Santos (SP), tais atividades estão presentes em diferentes níveis. Neste estudo foram investigadas as concentrações de arsênio, cádmio, chumbo, cobre, cromo, níquel, selênio, zinco e mercúrio, além de isótopos estáveis de carbono e nitrogênio, em sedimentos, fragmentos vegetais e organismos marinhos, como invertebrados bentônicos, peixes bentívoros e mamíferos marinhos, coletados nos três estuários. As amostragens foram realizadas em 2015, sendo as análises de isótopos realizadas por EA-IRMS e as análises de metais pesados realizadas por ICP OES-VGA e ICP-MS. As razões isotópicas permitiram a distinção entre fontes de matéria orgânica e nível trófico. Exemplares da ictiofauna e de cetáceos analisados não apresentaram distinção entre os níveis tróficos 3 e 4, indicando uma dieta generalista para estes animais e potencial compartilhamento de nicho trófico. Os metais apresentaram maiores concentrações nos sedimentos do estuário de Santos, coincidindo com o local com maior intensidade de atividades antrópicas. Comparando os estuários há maior acumulação de: Cr, Cu, Zn e Hg em Paranaguá, As e Pb em Cananéia, e Cd, Ni e Se em Santos, resultados justificados por atividades antrópicas, fontes naturais e características geoquímicas de cada região. A tendência de biomagnificação de Se foi observada nas teias tróficas de todos os estuários, e de Zn e Hg nas teias de Paranaguá e Cananéia. Entretanto, As, Cr, Cu, Ni e Pb demostraram tendência a biodiluição nas teias tróficas estudadas, com maior bioacumulação em invertebrados bentônicos. Portanto, este estudo traz um panorama atual da distribuição espacial e trófica de metais pesados nos estuários, colaborando com o monitoramento e ações de gestão costeira. / The coastal region of Brazil is historically impacted by anthropic activities, which release contaminants such as heavy metals. In the estuaries of Paranaguá (PR), Cananéia and Santos (SP), these activities are present in different levels. In the present study, concentrations of arsenic, cadmium, lead, copper, chromium, nickel, selenium, zinc and mercury were investigated, as well as stable carbon and nitrogen isotopes in sediments, plant fragments and marine organisms such as benthic invertebrates, benthivorous fish and marine mammals, collected in the three estuaries. Samples were collected in 2015, with isotope analysis performed by EA-IRMS and heavy metal analysis performed by ICP OES-VGA and ICP-MS. Isotopic ratios allowed the distinction between organic matter sources and trophic level. The specimens of the ichthyofauna and cetaceans analyzed did not present distinction between trophic levels 3 and 4, indicating a generalist diet for these animals and a potential sharing of trophic niche. The metals have presented higher concentrations in the sediments from Santos estuary, what coincides with the place with greater intensity of anthropic activities. Comparing the estuaries, there is more bioaccumulation of Cr, Cu, Zn and Hg in Paranaguá, As and Pb in Cananéia, and Cd, Ni and Se in Santos; results which are justified by anthropic activities, natural sources and geochemical characteristics of each region. A biomagnification tendency of Se was observed in the trophic webs of all estuaries, and Zn and Hg in the Paranaguá\'s and Cananéia\'s webs. However, As, Cr, Cu, Ni and Pb displayed a tendency to biodilution in the studied trophic webs; with a higher bioaccumulation in benthic invertebrates. Therefore this study provides a current overview of the spatial and trophic distribution of heavy metals in the estuaries. Thus, it is collaborating with the monitoring and actions of coastal management.