Tesis sobre el tema "Delta13C"

PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO
COORDENAÇÃO DE APERFEIÇOAMENTO DO PESSOAL DE ENSINO SUPERIOR
CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO
PROGRAMA DE SUPORTE À PÓS-GRADUAÇÃO DE INSTS. DE ENSINO
A avaliação da fonte e origem de hidrocarbonetos e isótopos estáveis em sedimentos dos Cânions Grussaí e Almirante Câmara fazem parte do projeto HABITATS, que visa a caracterização ambiental da Bacia de Campos e a melhor compreensão da dinâmica do ecossistema. Neste estudo foram avaliados diversos parâmetros orgânicos como hidrocarbonetos alifáticos, aromáticos, hopanos e esteranos assim como a razão isotópica de carbono e nitrogênio. A fração alifática indica ao longo dos cânions a contribuição de plantas vasculares terrestres, bem como resíduos produtos derivados de petróleo, possivelmente de fluídos de perfuração não-aquosos ou material semelhante. A distribuição da concentração de hopanos e esteranos é característico da presença de óleo recente em todas as estações, o que pode estar associado a exsudações naturais de petróleo. A avaliação das concentrações de HPAs, auxiliadas por razões diagnósticas sugerem fonte pirogênica de contribuição. Na campanha de inverno, observa-se no Cânion Almirante Câmara um forte predomínio da queima de biomassa, no entanto, a razão isotópica de carbono e nitrogênio indica um material orgânico de origem tipicamente marinha, não corroborando as informações obtidas pelas analises de hidrocarbonetos. O largo numero de estações e parametros empregados permitem uma visão amplificada para avaliação.
The assessment of source and origin of hydrocarbons and stable isotopes in sediments from Grussaí and Almirante Câmara canyons is part of the HABITATS Project, which aim to characterize the environment of Campos Basin e a better understanding of the ecosystem dynamics. On this study several organic parameters were evaluate, such aliphatic and aromatic hydrocarbons, hopane, sterane and also the isotopic ratio of carbon and nitrogen. The aliphatic fraction over the canyons indicates the contribution of vascular land plants as well as residue oil products, possibly drilling non-aqueous fluids or similar material. The concentration distribution of hopanes or steranes is characteristic at all stations of recent presence of oil, which can be associated to natural oil seeps.The assessment of PAHs concentrations, assisted by diagnostic ratios suggests pyrogenic source contribution. In the winter campaign, is observed in Almirante Câmara canyon a predominance of biomass burning source, however, the isotopic ratio of carbon and nitrogen indicates marine source, which do not corroborate the information obtained by analysis of hydrocarbons. The large number of stations and parameters analyzed allow an amplified view for evaluation.

Le but de ces travaux de thèse fut de tester la performance des outils géochimiques (DIC(carbone inorganique dissous), delta13C, delta18O) afin de suivre le devenir du CO2 injecté dans des réservoirs géologiques. Dans un premier temps, un protocole analytique a été mis au point afin de mesurer l'outilDIC-delta13C, par spectrométrie de masse à flux continu. Le premier site d'étude était le lac Pavin (Massif Central, France) ; ses couches d'eaux profondes isolées, renferment d'importantes quantités de CO2. Cette particularité permet de l'assimiler à un réservoir géologique stockant d'importantes quantités de CO2 d'origine biogénique et magmatique (fournit par une source sous lacustre). L'outil DIC-delta13C a permisde montrer d'une part, que la réactivité et les sources et puits de DIC étaient essentiellementgouvernés par des processus biogéochimiques (photosynthèse, oxydation de la matièreorganique, méthanotrophie, méthanogénèse) et d'autre part, de détecter un transfert de CO2entre les couches d'eaux superficielles et profondes du lac. Le second était le site expérimental du Lamont Doherty (NY, USA) composé d'un puitsde forage instrumenté. Des injections de fluide saturé en CO2 ont été réalisées au niveau d'une zone perméable, à l'interface de roches basiques et sédimentaires. Après une pèrioded'incubation, l'évolution des compositions chimiques (DIC, Ca2+, Mg2+. . . ) et isotopiques(delta13C, delta18O) des fluides extraits ont mis en évidence des processus de mélange entre le fluideinjecté et l'eau de l'aquifère ainsi que des interactions CO2-eau-roche : principalement ladissolution de calcite, et à un ordre moindre la dissolution des minéraux silicatés. De même,l'outil delta13C-DIC a mis en évidence un dégazage de CO2, in situ
The aim of this research works consisted in studying the behaviour of the carbonate system (dissolved inorganic carbon: DIC) following a CO2 injection (artificial or natural), in geological reservoirs. One part of the study consisted in improving an analytical protocol for the measurementof delta13CDIC and DIC, using a continuous flow mass spectrometer. As a first study, we have focused our attention on the Pavin Lake (Massif Central,France). Owing to its limnologic characteristics (meromictic lake) and a deep volcanic CO2contribution, it can be viewed as a natural analogue of reservoir storing important quantitiesof CO2 in the bottom part. Isotopic measurements (delta18O, delta13CDIC) allowed to better constrainthe dynamics of the lake (stratification, seasonal variations), the magnitudes of biologicalactivities (photosynthesis, organic matter decay, methane oxidation, methanogenesis), carbonsources (magmatic, methanogenetic), and the hydrological budgets (sublacustrine inputs). The second study was conducted on the Lamont-Doherty test well site (NY, USA). Itincludes an instrumental borehole which cuts through most of the section of the Palisades silland into the Newark Basin sediments. Single well push-pull tests were performed: a testsolution containing conservative tracers and a reactive tracer (CO2) was injected at apermeable depth interval located in basaltic and metasedimentary rocks. After an incubationperiod, the test solution/groundwater mixture was extracted from the hydraulically isolatedzone. Isotopic measurements (delta18O, delta13CDIC) confronted to chemical data (major elements)allowed to investigate the extent of in-situ CO2-water-rock interactions: essentially calcite dissolution and at a lesser extend silicate dissolution. . . And for one of the test, CO2 degassing

Soils of Northern Hemisphere forests contain a large part of the global terrestrial carbon (C) pool. Even small changes in this pool can have large impact on atmospheric [CO2] and the global climate. Soil respiration is the largest terrestrial C flux to the atmosphere and can be divided into autotrophic (from roots, mycorrhizal hyphae and associated microbes) and heterotrophic (from decomposers of organic material) respiration. It is therefore crucial to establish how the two components will respond to changing environmental factors. In this thesis I studied the effect of elevated atmospheric [CO2] (+340 ppm, 13C-depleted) and elevated air temperature (2.8-3.5 oC) on soil respiration in a whole-tree chamber (WTC) experiment conducted in a boreal Norway spruce forest. In another spruce forest I used multivariate modelling to establish the link between day-to-day variations in soil respiration rates and its δ13C, and above and below ground abiotic conditions. In both forests, variation in δ13C was used as a marker for autotrophic respiration. A trenching experiment was conducted in the latter forest in order to separate the two components of soil respiration. The potential problems associated with the trenching, increased root decomposition and changed soil moisture conditions were handled by empirical modelling. The WTC experiment showed that elevated [CO2] but not temperature resulted in 48 to 62% increased soil respiration rates. The CO2-induced increase was in absolute numbers relatively insensitive to seasonal changes in soil temperature and data on δ13C suggest it mostly resulted from increased autotrophic respiration. From the multivariate modelling we observed a strong link between weather (air temperature and vapour pressure deficit) and the day-to-day variation of soil respiration rate and its δ13C. However, the tightness of the link was dependent on good weather for up to a week before the respiration sampling. Changes in soil respiration rates showed a lag to weather conditions of 2-4 days, which was 1-3 days shorter than for the δ13C signal. We hypothesised to be due to pressure concentration waves moving in the phloem at higher rates than the solute itself (i.e., the δ13C–label). Results from the empirical modelling in the trenching experiment show that autotrophic respiration contributed to about 50% of total soil respiration, had a great day-to-day variation and was correlated to total soil respiration while not to soil temperature or soil moisture. Over the first five months after the trenching, an estimated 45% of respiration from the trenched plots was an artefact of the treatment. Of this, 29% was a water difference effect and 16% resulted from root decomposition. In conclusion, elevated [CO2] caused an increased C flux to the roots but this C was rapidly respired and has probably not caused changes in the C stored in root biomass or in soil organic matter in this N-limited forest. Autotrophic respiration seems to be strongly influenced by the availability of newly produced substrates and rather insensitive to changes in soil temperature. Root trenching artefacts can be compensated for by empirical modelling, an alternative to the sequential root harvesting technique.

Changes in the concentration of atmospheric carbon dioxide (pCO2) affect global climate. Accurate determination of paleo-pCO2 can therefore provide information on the response of climate to changing pCO2. Such pCO2 proxies have been developed from a variety of terrestrial (e.g., plant stomata, paleosol carbonate, and liverworts) and marine (e.g., alkenones and boron) substrates. However, these proxies show a wide range of values and uncertainty throughout the Cenozoic and especially for the early Paleogene (53-63 mya). Here, I demonstrate the use of the carbon isotope composition of n-alkanes extracted from C3 plant waxes as an accurate recorder of changes in atmospheric chemistry. My results show that the uncertainty and range of pCO2 estimates determined using this new proxy are similar to other proxies. Because n-alkanes are abundant, chemically resistant, and not subject to degradation, this proxy represents an excellent opportunity to reconstruct pCO2 across the last 400 Myr of Earth history. By examining across 4 different chain lengths (n-27, n-29, n- 31, and n-33), I find that only n-29 and n-31 show clear changes in carbon isotope discrimination in response to changes pCO2, whereas chain-lengths n-27 and n-31 did not show any significant response. Using chain lengths n-29 and n-31, I calculate early Paleogene pCO2 = 566 ? 190 and 469 ? 165 ppmv (median ? 1?), respectively. These results demonstrate that n-alkanes can serve as a potential pCO2 proxy across geologic timescales.

Les reconstructions paléoclimatiques sont classiquement basées sur l’analyse géochimique de sédiments pélagiques. Néanmoins, les travaux sont parfois rendus difficiles du fait du mélange dans les sédiments analysés de particules de diverses origines. L’hypothèse de départ est de comprendre comment la composition relative des différents types de particules peut contraindre la signature géochimique globale mesurée sur carbonate total. L’application de cette problématique a été réalisée sur des séries pélagiques du Crétacé inférieur des bassins Vocontien et Ibérique. L’obtention des signatures isotopiques de chaque type de particule est rendue possible par l’utilisation d’un protocole de microfiltration sur membrane de 60µm à 2µm. Les valeurs isotopiques du carbone obtenues sur les coccolithes et les Nannoconus montrent une évolution comparable à celle enregistrées par la roche totale. Ainsi, ces mesures du 13C confirment qu’au moins la totalité de la zone photique est affectée par la perturbation du cycle du carbone du Valanginien. Alors que les travaux antérieurs sur bélemnites évoquaient un refroidissement lors de l’événement Weissert, les données sur l’oxygène des coccolithes et des Nannoconus indiquent un réchauffement. Ceci nous conduit à proposer une stratification de la colonne d’eau avec des échanges très restreints entre les masses superficielles (coccolithes+Nannoconus) et les masses sous-jacentes (bélemnites). Cette stratification permettrait une augmentation de la séquestration de matière organique dans des fonds dioxiques et serait responsable de l’excursion positive du carbone observée.

Un bilan sur l'histoire des ongules du paleogene d'europe occidentale est etabli d'apres l'etude de deux groupes particulierement representatifs dans les faunes de cette periode: les ruminants de l'oligocene et les cainotheriidae post-grande coupure. Ces etudes systematiques qui reposent sur un materiel inedit provenant des gisements dates des phosphorites du quercy completent largement les resultats des travaux anterieurs consacres aux ongules de cette epoque. L'histoire des ongules est marquee par differentes phases (extinctions, apparitions par diversification ou par immigration, adaptations, changements dans les proportions relatives des artiodactyles et des perissodactyles) liees aux modifications de l'environnement. Dans cette perspective, la diversite relative de ces deux groupes ainsi que les modifications observees, tant sur le plan dentaire que sur le plan du squelette appendiculaire sont analysees. Sur ce dernier point, une etude consacree plus specialement aux differents ruminants a permis, sur la base d'observations effectuees sur des ruminants actuels, de les situer dans leur environnement respectif. Toujours dans ce cadre, une analyse de micro-usures des facettes dentaires d'artiodactyles a dents selenodontes pre-et-post grande coupure est realisee a titre experimental. Enfin, les variations isotopiques du carbone et de l'oxygene de la carbonate hydroxylapatite de l'email dentaire d'ongules eocenes/oligocenes sont analysees afin d'etablir des correlations avec les courbes de d#1#3c et d#1#8o determinees en milieu marin

During the 1970s to the 1990s, Steller sea lions (Eumetopias jubatus) in Alaska declined severely, resulting in the western stock's listing as endangered under the United States Endangered Species Act. The localized depletion of their main food source around rookeries and haul out sites was the primary cause of their depletion. The western stock has still not recovered to historical levels. Therefore, scientists have continued to study Steller sea lions diet and foraging habits. One approach has been through stable isotope analysis of their various tissues. Analysis of their vibrissae, or whiskers, provides an exact record of an individual's diet from birth to the present. However, scientists so far have only measured stable isotope values of a single vibrissa from an individual, assuming no significant difference among vibrissae within or between cheeks. They have not accounted for the possibility of variable stable isotope accumulation in an individual's different vibrissae. In this study, I tested the assumption of no significant individual variability among vibrissae by examining the δ¹³C and δ ¹⁵N values in all of the vibrissae on five Steller sea lion pups recovered in Alaska. δ¹⁵N values did not differ between vibrissae on a cheek or between vibrissae from left and right cheeks. The δ ¹³C values did not differ between vibrissae within cheeks; however, δ ¹³C values were significantly different between the left and right cheeks of Lowrie Island Pup and PWS 29 Pup. This between cheek variation is most likely due to small sample size rather than different stable isotope incorporation. The lack of δ¹⁵N value variation within or between cheeks, as well as the lack of δ¹³C variation within cheeks, supports the assumption that stable isotope accumulation is similar between all vibrissae and validates sampling protocols of previous studies collecting just the longest, thick vibrissa from a Steller sea lion. More studies similar to this one are needed to verify these findings and to look at variability in stable isotope incorporation of juvenile and adult Steller sea lion vibrissae as well as other mammal species.

Dans le contexte actuel de l’augmentation de la concentration en CO2 dans l’atmosphère, l’étude du fonctionnement des forêts tempérées comme puits ou sources de C est essentielle. Les études fonctionnelles à des échelles plus fines, comme celle de l’arbre, permettent d’améliorer les estimations des flux de C dans les écosystèmes forestiers. Ce travail de thèse examine principalement les signaux isotopiques (quantité de 13C par rapport au 12C, delta13C) de deux composantes du bilan carboné à l’échelle de l’arbre : 1) Le delta13C du CO2 respiré par l’arbre avec en particulier la caractérisation des variations temporelles du delta13C du CO2 respiré par le tronc en relation avec le fonctionnement de l’arbre. Nos résultats montrent une forte variabilité du delta13C du CO2 respiré par le tronc due à des changements à la fois de delta13C des substrats respiratoires et de l’intensité d’utilisation de ces substrats. 2) Le delta13C du cerne comme indicateur du fonctionnement de l’arbre en réponse au climat. Ce travail a montré que lors de la formation du bois final, les variations du delta13C des sucres assimilées par les feuilles sont transmises et enregistrées dans le delta13C du cerne. Ces résultats valident par une approche fonctionnelle l’utilisation du delta13C du cerne comme archive des réponses fonctionnelles de l’arbre au climat. En améliorant la compréhension des signaux isotopiques, ce travail de thèse permet d’avancer dans leur interprétation à des échelles spatio-temporelles plus grandes, comme dans l’étude des composantes du bilan de C à l’échelle de l’écosystème ou des réponses des forêts aux variations inter-annuelles du climat
Because of the current atmospheric CO2 increase, study of temperate forest functioning as C source or sink becomes essential. Functional studies at smaller scales, like tree scale, allow to improve C flux estimates at the forest level. This thesis work mainly examines isotopic signals (13C quantity compared to 12C, delta13C) of two components of tree-C balance : 1) delta13C of CO2 respired by tree and characterization of its temporal variations, in relation to tree functioning. Our results showed a high variability of respired CO2 delta13C due to changes either in respiratory substrate delta13C or in intensity of substrate use. 2) Ring delta13C as an indicator of tree functioning in response to climate changes. This work showed that during latewood formation, variations of delta13C of new assimilated sugars were transmitted and recorder in the ring delta13C. These results validate, by a functional approach, the use of ring delta13C as an archive of tree functional responses to climatic conditions. These studies improve the understanding the tree isotopic signals and their interpretation at larger spatial and temporal scales, like in the study of ecosystem C balance or in the study of forest responses to inter-annual climate changes

Les hydrocarbures aromatiques polycycliques (HAP) sont des composés organiques présents dans l’ensemble des compartiments environnementaux. Dans l’atmosphère, leurs sources sont à la fois naturelles (feux de biomasse, éruptions volcaniques) et anthropiques (industrie, transport, chauffage résidentiel). Une fois émis, sous forme gazeuse ou adsorbés à la surface de particules atmosphériques, les HAP sont susceptibles d’être impliqués dans des processus physico-chimiques tels que la photodégradation et/ou des réactions d’oxydation avec différentes espèces radicalaires. Du fait de leur toxicité avérée, ces composés font l’objet de différentes réglementations, législations françaises et européennes. Concernant le compartiment atmosphérique, seul le benzo(a)pyrène présente aujourd’hui des seuils d’émission à respecter. Afin de faire évoluer ces textes et de mettre en place des mesures de réduction d’émissions, diverses approches ont été développées dans le but de différencier leurs sources dans l’atmosphère. L’approche moléculaire, basée sur les profils moléculaires et les rapports de concentrations, permet d’apporter des informations quant à leurs origines. En revanche, elle souffre de biais induits par les conditions de formation des HAP (température, conditions environnementales…) et par les processus physico-chimiques dans lesquels ils sont impliqués. L’objectif principal de ce travail est de mettre en place une méthodologie de traçage de sources des HAP particulaires par une approche isotopique. Le développement du protocole analytique a été réalisé pour déterminer la composition isotopique moléculaire des HAP particulaires par GC/C/IRMS. Il a été montré que la réactivité des HAP sous l’action d’oxydants (O3, NO2, OH) et/ou de la lumière solaire n’induisait pas de variation significative de la composition isotopique moléculaire des HAP. Cette méthodologie a ainsi pu être appliquée sur des échantillons naturels, prélevés sur des sites caractérisés par des sources spécifiques. Il a été montré que les 13C/12C des HAP, en complément de données moléculaires, permettent de différencier les origines de ces composés. Par exemple, les caractéristiques moléculaires et isotopiques de HAP issus de la combustion de plusieurs espèces de bois d’origine méditerranéenne ont été déterminées en appliquant cette méthodologie à des échantillons collectés directement à l’émission. Enfin, dans le cadre de l’étude de la pollution et de ses impacts dans le Bassin d’Arcachon, les apports atmosphériques en HAP ont été mesurés par l’approche moléculaire couplée à d’autres outils (rétrotrajectoires, oxydants, roses des vents…) afin de compléter le diagnostic environnemental
Polycyclic Aromatic Hydrocarbons (PAH) are carcinogenic compounds, present in all the compartments of the Environment. In the atmosphere, their sources are both from natural (biomass burning, volcanic emissions...) and anthropogenic (transport, industry, residential heating...) origins. Once emitted in the atmosphere, PAH are distributed between the gaseous or particulate phases and may be involved in different physico-chemical processes such as photodegradation, radical-initiated oxidations... Due to their carcinogenicity, PAH emissions are nowadays subjected to various regulations from France and more largely, European Union. In the atmosphere, benzo(a)pyrene has been selected as representative of the PAHs because of its high toxicity. In order to improve regulations involving emission reductions, several methodologies have been developed to perform source apportionment. The most commonly used in the literature is the molecular approach, based on molecular profiles and particular ratios. Nevertheless, conditions of PAH formation and physico-chemical processes affect these characteristic values. The main objective of this work was to develop a new methodology of particulate-PAH source tracking based on the molecular isotopic composition. The development of analytical procedure was performed to determine 13C/12C of PAHs by GC/C/IRMS. The study of the impact of PAH reactivity in the presence of O3, NO2, OH and/or solar radiations shows that no significant isotopic fractionation is induced on their isotopic compositions. Molecular isotopic approach was applied on natural particles, collected at different specific sites: 13C/12C of PAHs and molecular data allow differentiating particulate-PAH sources. Therefore, determinations of molecular and isotopic characteristics have been undertaken by applying this methodology on particulate-PAHs emitted during the combustion of fifteen Mediterranean woods. Finally, molecular approach coupled with different parameters (back-trajectories, oxidant concentrations, wind roses...) enables to measure the levels of PAH concentrations in the atmosphere in order to evaluate their impacts as a source of pollution in the Arcachon Bay

A l’échelle de l’arbre (de la feuille à la plante entière), le δ13C de la matière organique est généralement considéré à différentes échelles temporelles (de l’instantané à la saison de croissance) comme un intégrateur des processus physiologiques et des conditions environnementales prévalant lors de l’assimilation du CO2 (Ehleringer et al. 1988 ; Guehl et al. 1993). En particulier, les cernes de croissance constituent potentiellement une archive physiologique et climatique facilement datable au pas de temps annuel. Il est maintenant considéré que ces informations pourraient être obtenues à une résolution temporelle infra-annuelle par l’étude des variations du δ13C au sein même du cerne. L’objectif principal de cette thèse est d’étudier le déterminisme de ces variations intra-annuelles et de préciser quelles sont les informations physiologiques et environnementales qu’il est possible d’extraire du signal isotopique saisonnier au sein du cerne. Notre approche a tout d’abord consisté à étudier expérimentalement une partie des processus pouvant influencer, lors de la croissance, les variations de composition isotopique de la matière organique des feuilles, des tiges et du cerne de l’année en se focalisant sur la composition biochimique et la discrimination lors de la respiration. Les modèles d’étude étaient des espèces décidues de climat tempéré (Q. Petraea et F. Sylvatica). Dans un second temps, les connaissances issues de ces expérimentations ainsi que celles de la littérature ont été utilisées pour élaborer un modèle mécaniste simulant le bilan isotopique du carbone à l’échelle de l’arbre. Ce modèle a été couplé à CASTANEA, un modèle simulant le bilan carboné, hydrique et énergétique à l’échelle d’un peuplement forestier, puis calibré et validé sur des mesures de variations intra-annuelles de δ13C au sein de cernes de chênes prélevés en forêt de Barbeau (site ECOFOR et CARBOEUROPE-IP). Notre étude a montré (1) que les variations saisonnières du δ13C de la matière organique des feuilles, des tiges et du cerne sont peu influencées par les variations de composition biochimique (teneurs en lignine et holocellulose en particulier) et sont liées principalement à la dynamique de mobilisation des réserves en début de croissance et à l’influence des conditions environnementales sur la discrimination photosynthétique pendant le reste de la croissance, (2) que la corrélation entre signature isotopique de la matière organique du cerne dans le bois d’été et conditions climatiques (ici, principalement l’humidité relative et le VPD) pouvait être expliquée physiologiquement à l’échelle intra-saisonnière et (3) que le signal isotopique dans le cerne relatif aux changements intra-saisonniers des conditions climatiques est fortement atténué relativement à celui au niveau des feuilles
At tree-scale, organic matter δ13C is generally considered as an integrator of physiological processes and environmental conditions prevailing during CO2 assimilation process (Ehleringer and al. 1988; Guehl and al. 1993). In particular, tree rings constitute a physiological and climatic archive easily datable at a yearly timestep. It is now considered that this information could be extracted at an intra-annual resolution from the intra-ring δ13C variations. The main objective of this thesis was to study the determinism of these intra-seasonal variations and to specify what are the physiological and environmental information that it is possible to extract from the δ13C signal within rings. Our approach consisted first in studying experimentally a part of the processes likely to influence, during growth, the variations of the bulk matter δ13C in leaves, stems and current-year ring by focusing on the biochemical composition and the respiratory discrimination. The studied species were deciduous trees: european beech (F. Sylvatica L. ) and sessile oak (Q. Petraea Matt. (Liebl. )). In a second step, data from these experiments as well as literature data have been used to elaborate a mechanistic model simulating the carbon isotopic balance at tree-scale. This model has been coupled with CASTANEA, a model simulating the carbon, water and energy balances at stand-scale, then calibrated and validated on measurements of intra-annual variations of δ13C within oak rings, sampled in the Barbeau forest (ECOFOR and CARBOEUROPE-IP site). Our study has shown (1) that the intra-annual variations of the δ13C of the organic matter of leaves, stems and ring are little influenced by variations in biochemical composition (in particular, lignin and holocellulose contents) and are mainly related to the mobilization of carbon reserves at the beginning of growth and to the influence of environmental conditions on the photosynthetic discrimination during the rest of the growth, (2) that the correlation between the bulk matter δ13C of the latewood and climatic conditions (mainly relative humidity and VPD) can be physiologically explained at intra-seasonal scale and (3) that there is a strong attenuation of the carbon isotopic signal in relation to the changes in climatic conditions from the leaf to the ring

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Estudos quimioestratigráficos de δ13C, δ18O e 87Sr/86Sr têm fornecido excelentes resultados em terrenos Precambrianos, onde a deformação e ausência de marcadores bioestratigráficos dificultam o empilhamento e correlação entre os estratos. Através da correlação com trends de variação secular dos oceanos, as idades de deposição de carbonatos marinhos, submetidos a variados fácies metamórficos, vêm sendo determinada. A idade dos metassedimentos da Faixa Seridó (Província Borborema, NE do Brasil) tem sido discutida por mais de três décadas. Enquanto algumas pesquisas, fundamentadas principalmente em estudos estruturais, assumem idade Paleoproterozóica, estudos radiométricos levantam a possibilidade de uma idade Neoproteozóica. Com o objetivo de contribuir para a elucidação deste problema foi feito um estudo detalhado das flutuações de δ13C e 87Sr/86Sr em mármores intercalados no Grupo Seridó, em diversas porções da Faixa Seridó. Na Formação Jucurutu, base do Grupo Seridó, os intervalos de δ13C demonstram a existência de três níveis estratigráfcios distintos: (i) mármores basais com δ13C entre +8,3 a +11,8 PDB (cidades de Jucurutu - JUC, Ipueira - IP, e entre as cidade de Caicó-Jardim do Seridó - CAIJAR e Várzea-São Joâo do Sabugi - VSJS); (ii) mármores intermediários com δ13C de +6,7 a +8,7 PDB (localidade de Almino Afonso - AF) e (iii) mármores superiores com +0,7 a +3,8 PDB (cidade Messias Targino e São Rafael - MT e SRF respectivamente). Os mármores basais são constituídos por calcita (CaCO3 > 96%, MgCO3 < 3%) com anfibólio (tremolita, edenita e Mg-horblenda), flogopita, quartzo e opacos como acessórios. Próximo ao contato com o paragnaisses os mármores exibem valores de δ13C < 8,3 PDB, maior abundância de silicatos, e modificações na composição da rocha total (aumento da razão Mg/Ca, SiO2 e diminuição de Sr) e diminuição dos valores de δ18O. A correlação entre os isótopos de C e O, e razões Mn/Sr e Mg/Ca, indicam trends de alteração isotópica por reações de descarbonatação. O perfil Almino Afonso representa as intercalações estratigraficamente intermediárias da Formação Jucurutu. Mineralogicamente é bastante similar aos mármores imediatamente inferiores, com calcita (CaCO3 > 97%, MgCO3 < 0,6%), tremolita, flogopita, quartzo, opacos e wollastonita (Wo > 99% - amostras sem anfibólio e mica). O desenvolvimento da wollastonita é associada à percolação de fluído residuais magmáticos provenientes do granito Umarizal. Nos mármores com wollastonita a composição de δ13C é negativo ou inferior a +6,7 PDB, é registrado um aumento da razão Mg/Ca e de SiO2, e diminuição do teor de Sr. O caráter alterado das amostras é demonstrado nas correlações entre os isótopos de C e O, Mn/Sr, Mg/Ca, CaO através da definição de trends de alteração. Os mármores estratigraficamente superiores da Formação Jucurutu, apresentam diferenças texturais e mineralógicas marcante. O perfil MT é constituído essencialmente por calcita (CaCO3 < 97% e MgCO3 < 0,3%) e subordinadamente wollastonita (Wo < 50%; En < 49,%; Fs < 1,3) e dolomita. O perfil SRF apresenta em proporções variáveis calcita (CaCO3 > 93%, MgCO3 < 4%), dolomita (CaCO3 ≅ 55%, MgCO3 ≅ 44%), anfibólio (tremolita, Mg-horbnlenda, edenita), mica, quartzo e opacos. Os valores de δ13C são extremamente homogêneos no perfil MT (+2,3 a +3,7 PDB) e variáveis no perfil SRF ( 8,9 a +3,8 PDB) em conseqüência da percentagem de silicatos e da razão calcita/dolomita nas amostras. A avaliação do grau de alteração por parâmetros geoquímicos, permitiram identificar como potencialmente alteradas amostras com δ13C < 0,7 PDB. As intercalações de mármores basais da Formação Seridó, apresentam valores de δ13C entre +8,9 a +10,7 PDB. São mármores constituídos por calcita (CaCO3 > 92%, MgCO3 < 5%), com anfibólio (tremolita), flogopita, quartzo, opacos e sillimanita como acessórios. Um descrécimo progressivo de δ13C (+7,5 a +4,4 PDB) e aumento da percentagem de silicatos, marca o contato basal com o micaxisto. Essas feições em conjunto com a diminuição da razão Mg/Ca, aumento de SiO2 e diminução do Sr, caracterizam a presença de reações de descarbonatação e alteração isotópica das amostras. As correlação entre os isótopos de C, O e Mn/Sr, Mg/Ca e CaO confirmam as modificações isotópicas de C, via reação de descarbonatação. Valores negativos de δ13C marcam as intercalações estratigraficamente superiores da Faixa Seridó. São mármores extremamente homogênesos, constituídos apenas por calcita (CaCO3 > 97%, MgCO3 < 2%) e flogopita (+ dolomita no perfil CM). Os mármores do perfil SCM, por suas características essencialmente monominerálicas, não mostram oscilações na composição da rocha total rochas, em contrapartida, fortes oscilações na razão Mg/Ca são observados no perfil CM em conseqüência de variações na proporção calcita-dolomita. A dispersão nos valores de δ13C no perfil CM, quando observados alguns parâmetros geoquímicos, aponta para uma alteração gradativa dos valores de δ13C nas amostras desse perfil. A similaridade entre valores de δ13C na Formação Jucurutu e Seridó, indicam um período de contemporaneidade entre a sedimentação destas formações, o que inviabiliza a proposta de um hiato de tempo entre as mesmas. Comparado-se a composição isotópica de δ13C dos mármores da Faixa Seridó com curvas disponíveis na literatura, a idade de sedimentação do Grupo Seridó estaria no intervalo máximo de 640 a 573 Ma ou no intervalo mínimo de 590 a 573 Ma. Esta idade é corroborada pela quimioestratigrafica de 87Sr/86Sr, realizada em uma lente de cada nível estratigráfico das Formações Jucurutu e Seridó, apresentam valores de 87Sr/86Sr variando de 0,7074 e 0,7077, típico do Neoproterozóico. Estes valores são concordantes com idades de zircões detríticos da Formação Seridó (< 650 Ma) e com o plutonismo granítico brasiliano (555 a 517 Ma). Uma idade Neoproterozóica para as supracrustais da Faixa Seridó, contraria a proposta de uma evolução policíclica. Associações petrotectônicas, indicam que as formações Jucurutu e Equador depositaram-se num ambiente do tipo rift continental, enquanto que os metartubiditos da Formação Seridó, estariam relacionados a um ambiente tectonicamente ativo, marcando pela inversão da bacia. A reativação dos empurrões por transcorrências marcaria final do ciclo brasiliano na Faia Seridó. O plutonismo granítico teria se iniciado na fase contracional e continuado até a fase transcorrente

Holz aus Kurzumtriebsplantagen (KUP) mit Pappeln (Populus spp.) kann eine bedeutende Rolle im Mix der Bioenergieressourcen in Deutschland spielen. Trotz eines günstigen Energieinput-Energieoutput-Verhältnisses ist das Erreichen wirtschaftlich zufriedenstellender Ergebnisse mit KUP jedoch auf den meisten potenziellen Anbauflächen durch hohe Ansprüche der Pappeln an die Wasserversorgung erschwert. Hohe Produktivitätsraten der Pappeln sind an einen hohen Wasserverbrauch gebunden und viele Trockenheitsanpassungen führen zu deutlichen Ertragsrückgängen. In der vorgestellten Arbeit wurde eine sechsjährige Vollgeschwister-F1-Kartierungspopulation der Europäischen Zitter Pappel (Aspe, Populus tremula L., Wuchsperiode 1998-2003) physiologisch und genetisch untersucht, um mögliche Wege zu einer züchterischen Verbesserung der Trockenheitstoleranz von Pappeln diskutieren zu können. Dabei wurde das Zuchtziel der Trockenheitstoleranz als Minimierung der Ertragsrückgänge unter trockenen Bedingungen definiert. Neben wuchsleistungsbezogenen Größen (Biomassegesamtleistung (BM, oberirdische Dendromasse), Biomassezuwachs (iBM), Radialzuwachs (ir), Baumhöhe (h)) wurden physiologisch holzanatomische Eigenschaften untersucht, die retrospektiv anhand der Jahrringe messbar sind und zur nicht direkt messbaren Eigenschaft der Trockenheitstoleranz in einer Beziehung stehen. Diese waren die Kohlenstoff- und Sauerstoffisotopsignatur (δ13C, δ18O), die Faser- und Gefäßgliedlänge (FL, GL), die Gefäßlumenquerschnittsfläche (AG), die Gefäßdichte (GD), der potenziell Saftstrom leitende Querschnittsflächenanteil (LQ), der hydraulisch gewichtete Gefäßlumendurchmesser (Dh) und die röntgendensitometrische Holzdichte (RD). Um trockenheitsbedingte physiologische Reaktionen vom Einfluss der Juvenilität der Kartierungspopulation unterscheiden zu können, wurden regionaltypische Juvenilitätstrends der RD, FL, GL, und des ir anhand eines zweiten, für das östliche Deutschland repräsentativen Aspen-Kollektivs aus natürlicher Sukzession ermittelt. Bedingt durch Trockenheitsanpassungen bzw. eine bevorzugte Wurzelentwicklung nach dem Verpflanzen zeigte die Kartierungspopulation in den ersten drei Jahrringen Abweichungen von den regionaltypischen Juvenilitätstrends. In den Trendverläufen der Kartierungspopulation heben sich die beiden Trockenvegetationsperioden 2000 und 2003 ab, wobei bis zum Sommer 2003 infolge des Starkniederschlages 2002 (Flut) ein außergewöhnlich gutes Grundwasserangebot herrschte. Alle untersuchten phänotypischen Eigenschaften zeigten 2000 starke trockenheitsbedingte Abweichungen. Im Jahrring 2003 wichen nur die GL und die RD von ihren Juvenilitätstrends ab. Außerdem konnte anhand der δ13C und δ18O Werte eine signifikante Abnahme der Wassernutzungseffizienz bzw. eine Zunahme der Transpiration im Jahr 2003 gezeigt werden. Die übrigen Größen folgten ihren Juvenilitätstrends und stiegen an. Die Jahrringdatensätze 2000 und 2003 der RD waren nicht signifikant mit der BM korreliert, dagegen zeigten die δ13C Datensätze 2002 und 2003 schwach positive Korrelationen mit der BM. Der trockenheitstoleranteste Genotyp verband seine überdurchschnittliche BM mit einer hohen Wassernutzungseffizienz (angezeigt durch überdurchschnittliche δ13C Werte), mit einer überdurchschnittlichen AG und mit einer nicht unterdurchschnittlichen RD in Höhe des Populationsmittels. Aufgrund des Fehlens negativer Korrelationen zwischen BM und δ13C bzw. BM und RD in der vorliegenden Arbeit können δ13C und RD als nützliche Weiser für die Unterscheidung der Trockenheitstoleranz verschiedener Aspen zu züchterischen Zwecken vorgeschlagen werden. Außer der BM unter trockenen Bedingungen kann keine der untersuchten Eigenschaften als alleiniger Trockenheitstoleranzweiser empfohlen werden. Zu einer Trockenheitstoleranzbewertung sollten Merkmalspaare verwendet werden, von denen ein Merkmal positiv mit dem Ertrag korreliert ist und das andere eine Trockenheitsanpassung verkörpert. Dadurch werden sowohl das primäre Zuchtziel eines höchstmöglichen Ertrages als auch eine bessere Trockenheitsangepasstheit berücksichtigt. Zwei verschiedene Trockenheitstoleranzindizierungen wurden angewendet, um die Kartierungsnachkommen entsprechend ihrer Trockenheitstoleranz einem Ranking zu unterziehen. Dabei wurden in beiden Fällen Bäume mit einem höheren Ertrag besser platziert. Der zweite Schwerpunkt der Arbeit lag auf der genetischen Kartierung von Quantitative Trait Loci (QTL) für die untersuchten phänotypischen Jahrringeigenschaften mit Bezug zur Trockenheitstoleranz. Als Basis für das QTL Mapping wurden, der Pseudo-Testcross-Mapping-Strategie folgend, genetische Kopplungskarten für die Elternbäume der Kartierungspopulation konstruiert. Die maternale Karte (P. tremula, „Schandau 4“) deckte mit 157 Markern (144 AFLP, 13 SSR) in 30 Kopplungsgruppen 1.369 cM ab, die 21 paternalen Kopplungsgruppen mit 148 Markern (132 AFLP, 16 SSR) überspannten 1.079 cM des Genoms (P. tremula, „Lichtenhain 1“). Die im Vergleich zur haploiden Chromosomenzahl der Pappeln (19) hohen Zahlen an Kopplungsgruppen sowie die hohen Zahlen an Doublets und unkartierten Markern zeigten eine geringe Genomabdeckung an. So konnte nur eine begrenzte Zahl, höchstens zwei QTL für die untersuchten phänotypischen Jahrringeigenschaften mit Bezug zur Trockenheitstoleranz, kartiert werden. Ein QTL Bereich mit pleiotropem Effekt auf mehrere wachstumsbezogene Größen wurde auf der maternalen Kopplungsgruppe 1 (dem Populus Chromosom I zuzuordnen) detektiert. Die Signifikanz der Effekte dieses QTL auf den Radialzuwachs entwickelte sich steigend mit zunehmendem Baumalter
Wood production in short rotation coppices (SRC) with poplar (Populus spp.) can contribute significantly to the future bio energy supply mix in Germany. Although the energy-input to energy-output ratio is rather good, SRC often do not meet cost effectiveness due to high water demand of poplar species. High biomass productivity depends on optimal water supply. Also, numerous adaptations to water deficits result in an undesirable decrease of yield. Combined physiological and genetic investigations were conducted within a six-year old F1-full-sib crossbred population of European aspen (Populus tremula L., growing period 1998-2003). Possible implications on selection, breeding or improvement of poplar cultivars showing a high tolerance to water deficits are discussed. For the work presented here, the breeding goal of higher water deficit tolerance was defined as the minimisation of yield losses under dry conditions. Beyond growth related traits (aggregate yield (BM), aboveground woody biomass), biomass increment (iBM) and radial increment (ir), physiological and wood anatomical traits were included; these are related to reactions to water deficit and are measurable on tree rings retrospectively. These traits were the Carbon- and Oxygen isotope ratios (δ13C, δ18O), the fibre length and vessel element length (FL, GL), the vessel lumen cross sectional area (AG), the vessel density (GD), the cumulative vessel lumen area to cross sectional area ratio (LQ), the hydraulically weighted mean vessel lumen diameter (Dh) and wood density assessed by X-ray densitometry (RD). To distinguish the drought induced physiologic reactions from juvenile developmental patterns of the mapping population, juvenile trends of RD, FL, GL, and ir, which are representative of habitats in south-eastern Germany, were investigated in a second aspen collective that was selected from natural succession. During the first three years, the mapping population showed deviations from the juvenile trends due to water deficit adaptations or preferential root development, respectively. Due to drought in the growing seasons of 2000 and 2003, the juvenile trends show outstanding values for both years, although ground water supply in 2003 was exceptionally good following the intense rain event of 2002 (Elbe flood 2002). The tree ring traits of both years stand out from the juvenile trends due to drought adaptations. In 2000, all phenotypic traits showed a significant deviation from their respective trends. In 2003, only GL and RD showed an adaptation to drought as observable by a deviation from their juvenile trends. A significant decrease in water use efficiency (WUE) and an increase in net transpiration, respectively, were shown for 2003 by means of δ13C or δ18O values. All other traits showed an increase following their juvenile trends. RD data for 2000 and 2003 were not significantly correlated with BM, but δ13C data (and therefore WUE) for 2002 and 2003 revealed a weakly positive correlation with BM. The genotype that was most tolerant to water deficits showed a combination of a superior growth with a superior WUE (by means of δ13C), a superior AG, and an RD close to but not less than the population average. Due to the lack of negative correlation between BM and δ13C or BM and RD in the present work, δ13C and RD can be valuable proxies for the determination of drought tolerance of aspen trees for tree improvement purposes. Aside from BM under dry conditions, no other traits that were investigated can be recommended as a stand-alone proxy for water deficit tolerance. For a water deficit tolerance evaluation, pairs of traits should be used, of which one trait is positively correlated with yield and the other represents a water deficit adaptation. Both the primary breeding goal of the highest possible yield as well as a better water deficit tolerance should always be considered in this context. Two different drought tolerance indices were used to rank the individuals of the mapping population according to their water deficit tolerance. In both cases, trees with higher BM were ranked better. The second focus of the present work is on genetic mapping of Quantitative Trait Loci (QTL) for the investigated tree-ring traits that refer to water deficit reaction. As a basis for the QTL-mapping approach, genetic linkage maps were constructed for each parental tree of the F1-full-sib crossbred mapping-population following the two-way pseudo-testcross mapping strategy. The maternal map (P. tremula, “Schandau 4”) consisted of 157 markers (144 AFLP, 13 SSR) in 30 linkage groups and covered 1,369 cM. The 21 linkage groups of the paternal map (P. tremula, “Lichtenhain 1”) covered 1,079 cM of the genome (144 AFLP, 13 SSR). Compared with the haploid chromosome number (19) of the Populus genome, the high number of linkage groups, doublets and unlinked markers indicated low genome coverage. Only a low number of QTL was detected, maximal two per in¬vesti¬gated phenotypic trait with a relation to water deficit tolerance. One QTL having a pleiotropic effect on several growth related traits was detected on the maternal linkage group 1 (corresponding to the Populus Chromosome I). The significance of the QTL effects seemed to increase with tree age

This thesis explores the relationship between water infrastructure, ecological change, and the politics of planning in New Orleans and the Mississippi River Delta, USA. Complex assemblages of water control infrastructure have been embedded in the delta over the last several centuries in an effort to keep its cities protected from floodwaters and maintain its waterways as standardized conduits for maritime transportation. This thesis investigates the historical development of these infrastructural interventions in the delta’s dynamics, and shows how the region’s eco-hydrology is ensnared in the politics and materiality of pipes, pumps, canals, locks, and levees. These historical entanglements complicate contemporary efforts to enact large-scale ecosystem restoration, even while the delta’s landscape is rapidly eroding into the sea. This historical approach is extended into the present through an examination of how waterway standards established at so-called chokepoints in the global maritime transportation system (the Panama Canal, for example) become embedded and contested in coastal landscapes and port cities worldwide. Turning towards urban ecology, the thesis examines socioecological responses to the flooding following Hurricane Katrina in 2005, with a special focus on how infrastructure failures, flooding intensity, and land abandonment are driving changing vegetation patterns in New Orleans over the past decade. The thesis contributes new conceptual language for grappling with the systemic relations bound up in water infrastructure, and develops one of the first studies describing urban ecosystem responses to prolonged flooding and post-disaster land management. This provides insights into the impending planning challenges facing New Orleans and coastal cities globally, where rising sea levels are bringing about renewed attention to how infrastructure is implicated in patterns of ecological change, hazard exposure, resilience, and social inequality.

At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 2: Manuscript. Paper 3: Manuscript. Paper 4: Accepted. Paper 5: Manuscript.

Optimizing the extraction of oil and other hydrocarbon products from existing sites is important. One source of hydrocarbon products is reservoirs found within sedimentary rock formations. Understanding fluid behavior within such formations can be quite useful in optimizing oil production. Fluid behavior within sedimentary formations is influenced by the bedform structure and permeabilities within the formation. Thus, we are concerned with developing a physically and statistically valid method of characterizing sedimentary rock formations. The use of archetypal analysis to generate synthetic bedforms, as well as the use of Kriging to assign permeabilities within a bedform, was explored. With these tools, a characterization of a sedimentary rock formation can be created and fluid flow through the charactrerization examined. It appears that the bedform structure within a realization has a greater influence on fluid flow than any permeability structure created by utilizing Kriging.

Waterfront communities in the Mekong Delta live with the inundation of their homes and businesses from seasonal flooding every year. This project investigated housing types, social practices and feelings of vulnerability of local people in the Cai Rang waterfront community in Can Tho City. The project made a significant contribution to methods for assessing vulnerability, adaptability and resilience of inhabitants of flood-prone housing in Vietnam. It also developed a new concept of 'Deltaic Urbanism' that offers a better urbanist approach specifically for deltaic regions subject to the potential impacts of climate change.

Thesis (M.S. in Modeling, Virtual Environments and Simulations)--Naval Postgraduate School, September 2006.
Thesis Advisor(s): Christian J. Darken. "September 2006." Includes bibliographical references (p. 51-52). Also available in print.

The Jaca Basin lies to the south of the Pyrenean mountain chain, in Spain, and was formed by the Late Cretaceous and Tertiary convergence between the Iberian and European tectonic plates. During the Bartonian (Middle Eocene), sediment flux from the uplifting Pyrenees was deposited in this basin as the Belsué-Atarés Fm. deltaic system. At the same time, southward propagation of deformation from the orogen created a number of emergent thrusts and thrust-related anticlines along the margins of the basin and within the basin itself. The effect that the growth of these kilometre-scale structures had on the coeval marine depositional systems is the focus of this work. Although the effects that uplifting intrabasinal structures have on fluvial systems and the effects that basin margin structures have on marine systems are well covered in the literature, the influence of intrabasinal compressive structures on coeval marine sedimentation has been largely neglected. By undertaking detailed fades, palaeocurrent and compositional analysis of the Belsué-Atarés Fm. deltaics across the Jaca Basin, it has been found that local tectonics had the strongest control on the marine sedimentation. The structurally defined basin margins largely acted as barriers to external depositional systems, causing large parts of the basin to be dominated by marl deposition. However, a total of four structurally controlled low points through the northern and southern basin margins allowed the entry of large volumes of Pyrenean axial zone sediments, beginning at 41.5 Ma. These were composed of silts, sands and pebbles, and formed the axial deltaic system. Once in the basin, a total of ten, kilometre-scale, growing thrust-related anticlines acted as barriers to the progradation of the axial system, causing facies associations to vertically aggrade behind each structure. At 37.5 Ma, after 4 Myr of vertical aggradation, a basin-wide fall in relative sea-level allowed the facies associations to rapidly prograde, breaching the crests of each of the barrier anticlines. The principal controls on the distribution of facies associations through time (sequence development) in the Jaca Basin were therefore local tectonic ones, with relative sea-level being secondary. This finding calls into question the work of the few existing studies into marine intrabasinal growth structures, which tended to use passive margin sequence stratigraphic concepts i.e. assume that relative sea-level was the primary control on sequences. The development of new techniques, such as numerical modelling, is needed before these types of complex geological situations can be fully understood. The results of this work will be of great relevance to basin dynamics and fold kinematics studies, and for hydrocarbon exploration in thrust-top basin settings.

During the mid-Holocene, some of the world's first large-scale complex societies came into being within the lower and middle reaches of a number of large river systems. Around this time, as global sea-level stabilised, the hosting fluvial environments of Lower Mesopotamia, the Nile Delta and the North China Plain were evolving from spatially varied landscapes dominated by swampy marshland, to better-drained, more uniform floodplain environments. It is necessary to consider whether such environmental changes could have guided aspects of sociocultural evolution in these settings In the Nile Delta, the setting for which most data are available, these palaeolandscape changes are comprehensively mapped through the construction of a four-dimensional aggradation model of the Holocene alluvial plain. Development of this model takes place within the context of a full reinterpretation of the Upper Quaternary stratigraphy of the Nile Delta, which is itself further informed by substantial programmes of fieldwork in the western delta. The environmental changes were forced by a decrease in the rate of relative sea-level rise within the context of decreased discharge and sediment-supply due to regional climate change. A geoarchaeological model links these changes in the landscape to sociocultural developments taking place in Egypt between 5500 and 2500 BC. Increased adoption of agricultural practices in the delta was stimulated by a decrease in the primary productivity of the landscape, which then led to population growth and shifts in settlement styles. The emergence of the first Egyptian capital of Memphis at the delta apex can also be seen as having been facilitated by changes in the palaeogeography of the fluvio-deltaic environment. Such linkages between the changing deltaic landscapes and social change are crucial in understanding the formation of the Ancient Egyptian State (c. 3100 BC), which involved increased involvement of regional elites using the delta as both an agricultural resource and trade route.

Earlier researchers have produced conceptual models of Mississippi River delta plain development which divide the deltaic plain into upper and lower reaches. The upper deltaic plain has been described as an area composed mainly of lacustrine, lacustrine delta, backswamp, and crevasse channels, with minimal distributary development. The lower deltaic plain is characterized by numerous distributaries forming distributary systems and lobes. Detailed geomorphic mapping and chronologic reconstruction within the Atchafalaya Backwater Area of the upper deltaic plain of the Mississippi River has led to the recognition of a complex network of distributary development related to three distinct distributary systems that formed in the upper deltaic plain over the past 2500 years. These systems do not fit previous models of upper deltaic plain development. The East Atchafalaya Basin Protection Levee blocked Atchafalaya River water and sediment from entering the study area and burying these older distributary systems, preserving their surface expression and allowing their identification. Results show that distributary systems can be a major contributor to upper deltaic plain development and that these systems are not always related to the lower delta plain delta switching process. A stable Mississippi River position and a favorable gradient in the study area over the past 4,000 years appear to be responsible for the geomorphic development of the study area.

This thesis re-evaluates the history of fossil fuels in the Dampier sub-Basin, North West Shelf of Australia, from the stage of deposition of land plant debris. It then identifies potential source rock signatures from organic-inorganic interactions during diagenesis (including compounds such as sesquiterpanes and benzonaphthofurans), and explores future perspectives in fluid screening using novel site-specific isotopic parameters for light hydrocarbons. The approaches described herein can be applied to similar petroleum systems worldwide.

Afin de reconstruire le signal isotopique sédimentaire dans uncontexte d'upwelling côtier, nous avons développé un modèle couplé physique et biogéochimique pouvant prendre en compte le fractionnement des isotopes de l'azote au sein d'un réseau trophique. Le modèle biologique est un modèle NPZD (Nutriments, Phytoplancton, Zooplancton, Détritus) qui prend en compte le fractionnement des isotopes de l'azote lors de l'assimilation des nutriments et lors de l'excrétion du zooplancton. Le modèle physique POM (Princeton Ocean Model) simule la circulation de l'upwelling côtier. Appliqué pour différentes situations de niveaux marins, ce modèle couplé nous permet de reproduire les signaux sédimentaires d15N et flux d'azote organique et d'en tirer des conclusions sur les scénarios paléocéanographiques. Au large du Cap Blanc, Mauritanie, l'effet de la montée du niveau marin, par l'immersion de la plate forme continentale, semble être le principal facteur responsable lors de la dernière déglaciation des variations de flux d'azote organique et du signal isotopique au niveau des sédiments. Ceci nous permet de proposer que le bilan d'azote océanique au cours de la dernière déglaciation ait pu être plus équilibré et stable qu'initialement prévu. Cet effet s'accompagne d'une période de fonctionnement de l'upwelling qui aurait pu être plus longue au Dernier Maximum Glaciaire, aux environs de 10 mois, contre 4-5 mois pour l'actuel. Ce modèle a aussi été appliqué au système du Benguela (Afrique du Sud Ouest) pour étudier certains processus de recyclage.

L’estudi integrat de la hidrologia subterrània, la geologia i l’estratigrafia del ventall deltaic fòssil del massís de Sant Llorenç del Munt (Eocè, província Barcelona) ha permès definir el model hidrogeològic conceptual. Aquest contribueix a la comprensió del funcionament hidrodinàmic d’aquest tipus de sistemes, condicionats directa o indirectament per l’estratigrafia. Per a la caracterització hidrogeològica s’han realitzat diversos assajos de bombeig, s’ha estudiat l’evolució piezomètrica, s’han definit les fàcies hidroquímiques i s’han analitzat isòtops ambientals (δ2H i δ18O). A nivell geològic s’ha realitzat una cartografia a escala 1:25.000, s’han definit les unitats estratigràfiques i les seves relacions, s’ha correlacionat el registre litològic de pous i s’han elaborat 4 talls geològics del massís. S’han reconegut 10 unitats lito-hidroestratigràfiques, corresponents a diversos ambients sedimentaris. La part al·luvial esta formada per bretxa de clasts paleozoics (Bp), conglomerat clast-sostingut poligènic (Cp), conglomerat clast-sostingut carbonàtic (Cc), conglomerat matriu-sostingut poligènic (Cmp), conglomerat matriu-sostingut carbonàtic (Cmc) i gres i lutita vermells (GLv). La part marina està constituïda per conglomerat gris (Cg), gres gris (Gg), lutita gris (Lg) i calcària i marga (CM). La disposició estratificada del conjunt pren un cabussament general cap al NO. A nivell hidrogeològic s’ha constatat una permeabilitat per fracturació que desenvolupa aqüífers en conglomerat (Cp, Cc, Cg) i gres gris (Gg) classificats com a pobres, quelcom permeables. S’han establert 5 grups hidroquímics que han permès explicar l’evolució del flux al llarg del ventall deltaic, juntament amb les dades isotòpiques i estratigràfiques que han determinat les principals zones de recàrrega. El flux evoluciona des d’hidrofàcies bicarbonatades càlciques a la zona de ventall al·luvial cap a composicions enriquides en sodi i empobrides en calci cap a les parts profundes del mateix ambient. Aquests nivells aqüífers es recarreguen per precipitació directe al massís conglomeràtic. Els nivells més superficials tendeixen a ser drenats per les rieres mentre que els aqüífers més profunds es troben relativament confinats per litofàcies de gres i lutita vermells (GLv). Localment trobem conglomerats progradants que arriben fins a la part marina i recarreguen els nivells de gresos grisos de front deltaic (Gg). Les dades isotòpiques indiquen que els nivells aqüífers del front deltaic també es recarreguen a partir dels cursos d’aigua superficial. Al llarg d’aquesta unitat l’aigua s’enriqueix progressivament en magnesi i sulfat procedent de les mateixes litofàcies marines. En profunditat l’aigua subterrània es van enriquint en sodi i clor, a mida que perd calci, fins arribar als nivells aqüífers més profunds confinats per les litofàcies de lutita gris (Lg). Així, l’arquitectura sedimentària condiciona la hidrodinàmica del sistema, de manera que existeixen 4 unitats hidrogeològiques ben diferenciades. La primera unitat és un sistema aqüífer format per conglomerat de ventall al·luvial proximal (principalment litofàcies Cp, Cc). La segona unitat està formada pel cinturó de fàcies del ventall al·luvial distal (GLv) funcionant com aqüitard, tot i que puntualment hi apareguin conglomerats progradants. La tercera unitat és sistema aqüífer constituït per les fàcies de front deltaic (Cg, Gg), molt condicionada pel relleu i l’encaixament de les rieres. La darrera unitat està constituïda per les fàcies de prodelta (Lg) i funciona com aqüitard. Els principals sistemes aqüífers estan desenvolupats pel confinament de les litofàcies més permeables interdigitades amb els materials menys permeables. Aquest model hidroestratigràfic permet entendre com els principals elements estratigràfics i geològics condicionen la hidrodinàmica subterrània, permetent una millor gestió dels recursos hídrics en aquest tipus de sistemes.
El estudio integrado de la hidrogeología subterránea, la geología y la estratigrafía del abanico deltaico fósil del macizo de Sant Llorenç del Munt (Eoceno, provincia de Barcelona) ha permitido definir el modelo hidrológico conceptual. Éste contribuye a la comprensión del funcionamiento hidrodinámico de este tipo de sistemas, condicionados directa o indirectamente por la estratigrafía. Para la caracterización hidrogeológica se han realizado diversos ensayos de bombeo, se ha estudiado la evolución piezométrica, se han definido las facies hidroquímicas y se han analizado isótopos ambientales (δ2H i δ18O). A nivel geológico se ha realizado una cartografía a escala 1:25.000, se han definido las unidades estratigráficas y sus relaciones, se ha correlacionado el registro litológico de pozos y se han elaborado 4 cortes geológicos del macizo. Se han reconocido 10 unidades lito-hidroestratigráficas, correspondientes a varios ambientes sedimentarios. La parte aluvial está formada por brecha de clastos paleozoicos (Bp), conglomerado clasto-sostenido poligénico (Cp), conglomerado clasto-sostenido carbonático (Cc), conglomerado matriz-sostenido poligénico (Cmp), conglomerado matriz-sostenido carbonático (Cmc) y arenisca y lutita rojos (GLv). La parte marina está constituida por conglomerado gris (Cg), arenisca gris (Gg), lutita gris (Lg) y caliza y marga (CM). La disposición estratificada del conjunto toma un buzamiento general hacia el NO. A nivel hidrogeológico se ha constatado una permeabilidad por fracturación que desarrolla acuíferos en conglomerado (Cp, Cc, Cg) y arenisca gris gris (Gg) clasificados como pobres, algo permeables. Se han establecido 5 grupos hidroquímicos que han permitido explicar la evolución del flujo a lo largo del abanico deltaico, junto con los datos isotópicos y estratigráficos que han determinado las principales zonas de recarga. El flujo evoluciona desde hidrofácies bicarbonatadas cálcicas en la zona de abanico aluvial hacia composiciones enriquecidas en sodio y empobrecidas en calcio hacia las partes profundas del mismo ambiente. Estos niveles acuíferos se recargan por precipitación directa en el macizo conglomerático. Los niveles más superficiales tienden a ser drenados por los arroyos mientras que los acuíferos más profundos se encuentran relativamente confinados por litofacies de arenisca y lutita rojos (GLv). Localmente encontramos conglomerados progradantes que llegan hasta la parte marina y recargan los niveles de areniscas grises del frente deltaico (Gg). Los datos isotópicos indican que los niveles acuíferos del frente deltaico también se recargan a partir de los cursos de agua superficial. A lo largo de esta unidad el agua se enriquece progresivamente en magnesio y sulfato procedente de las mismas litofacies marinas. En profundidad el agua subterránea se va enriqueciendo en sodio y cloro, a medida que pierde calcio, hasta llegar a los niveles acuíferos más profundos confinados por las litofacies de lutita gris (Lg). Así, la arquitectura sedimentaria condiciona la hidrodinámica del sistema, de manera que existen 4 unidades hidrogeológicas bien diferenciadas. La primera unidad es un sistema acuífero formado por conglomerado de abanico aluvial proximal (principalmente litofácies Cp, Cc). La segunda unidad esté formada por el cinturón de facies de abanico aluvial distal (GLv) funcionando como acuitardo, a pesar que puntualmente esté atravesado por conglomerados progradantes. La tercera unidad es el sistema acuífero constituido por las facies de frente deltaico (Cg, Gg), muy condicionada por el relieve y el encajamiento de los arroyos. La última unidad está constituida por las facies de prodelta (Lg) y funciona como acuitardo. Los principales sistemas acuíferos están desarrollados por el confinamiento de las litofácies más permeables interdigitadas con los materiales menos permeables. Este modelo hidroestratigráfico permite comprender como los principales elementos estratigráficos y geológicos condicionan la hidrodinámica subterránea, permitiendo una mejor gestión de los recursos hídricos en este tipo de sistemas.
A conceptual hydrogeologic model of the fossil alluvial fan of the Sant Llorenç del Munt massif (Eocene, Barcelona province) has been defined after the integration of groundwater hydrology, geology and stratigraphy. This conceptual model contributes to a better understanding of the hydrodynamic behavior this kind of systems directly or indirectly controlled by the stratigraphy. For the hydrogeological characterization several pumping tests were conducted, the evolution of piezometric evolution has been studied, hydrochemical facies have been defined and environmental isotopes (δ2H and δ18O) have been analyzed. In terms of geology, a 1:25.000 scale mapping has been carried out, the stratigraphic units and their relations have been defined, the lithological record of wells has been correlated and four geological cross sections have been built up. 10 lito-hidroestratigraphic units have been recognized, which correspond to different sedimentary environments. The alluvial part is build up by: brecchia of Paleozoic clasts (Bp), clast-supported polygenic conglomerate (Cp), clast-supported carbonate conglomerate (Cc), matrix-supported polygenic conglomerate (Cmp), matrix-supported carbonate conglomerate (Cmc) and red sandstone and mudstone (GLv). The marine part consists of gray conglomerate (Cg), gray sandstone (Gg), gray mudstone (Lg) and limestone and marl (CM). The stratified set dips towards the NW. In terms of hydrogeology, hydraulic conductivity due to fracturing provide aquifers in conglomerates (Cp , Cc , Cg) and gray sandstone (Gg) classified as poor, somewhat permeable. 5 hydrochemical groups have been established which allow explaining the evolution of the flow throughout the fan delta. Together with isotopic and stratigraphic data the main recharge areas have been determined. The flow evolves from calcium bicarbonate hydrofacies in the area of alluvial fan to compositions enriched in sodium and reduced in calcium into the deep parts of the same environment. These aquifers levels are recharged by direct precipitation in the conglomeratic massif. The most superficial levels tend to be drained by streams while deeper aquifers are relatively confined by red sandstone and mudstone lithofacies ( GLv). Prograding conglomerates locally reach the marine levels and recharge gray sandstones of the delta front (Gg) levels. The isotopic data indicate that the aquifer levels of the delta front are also recharged by surface water. Throughout this unit water gets progressively enriched in magnesium and sulfate from the same marine litofacies. Groundwater gets progressively enriched in sodium and chlorine, as they lose calcium until reaching deeper aquifer levels that are confined by the grey mudstone litofacies (Lg). Thus, the sedimentary architecture affects the hydrodynamics of the system giving as a result four distinct hydrogeological units. The first unit is a conglomerate aquifer system that consists of proximal alluvial fan (mainly litofacies Cp, Cc). The second unit is formed by the distal alluvial fan facies (GLv) that works as an aquitard, although occasionally prograding conglomerates cut it. The third aquifer system unit is constituted by the delta front facies (Cg, Gg), highly influenced by the relief and streams entrenchment. The last unit consists of prodelta facies (Lg) that also works as an aquitard. The main aquifer systems are developed by confinement of the most permeable litofacies interfingering with less permeable materials. This hydrostratigraphic model allows understanding how the main stratigraphic and geologic elements condition groundwater flow and allow an enhanced water resource management in such systems.

This study aims to establish a depositional framework for an area of the Louisiana shelf, north-central Gulf of Mexico. The depositional history of the study area is poorly understood, especially within the last cycle of major eustatic fluctuation (~18, 000 yrs BP – present). Data sets used in this study include pre-existing and previously unanalyzed two-dimensional, highresolution seismic profile records (Acadiana 86 and Acadiana 89), geotechnical foundation boring data (Coleman and Roberts, 1988a), and an industry lease block survey report (Cole, 1983). Seismic sequence stratigraphic methods are employed in this study to analyze seismic profile data. Seismic sequence analysis results indicate the presence of five unconformable surfaces and five seismic facies units. Through correlation of seismic profile data with lithologic and chronologic data, it is possible to conclude that these seismic facies units represent shelf-margin deltaic deposition during the last lowstand of sea level (~18, 000 yrs BP), sourced by the Pearl River. .

Combined seismic and well interpretation methods can be used to elucidate detail of the subsurface architecture of fluvial and fluvio-deltaic deposits. Observations made from wireline and core logs, including facies and analysing the relative proportions of architectural elements and facies associations indicative of depositional sub-environments, can be used to interpret patterns of cyclicity, changes in local accommodation conditions, and periods of increased seasonal, tidal and marine influence. Horizon slices, taken from 3D seismic volumes aid in the visualisation of laterally discontinuous, often thinly-bedded, fluvial deposits. Seismic facies, when combined with core and wireline log facies, can be interpreted as a series of ‘seismic elements’. The relative proportions of seismic elements mapped out on horizon slices allows the interpretation of depositional environments and accommodation setting; allowing the distinction between fluvial and deltaic settings. A number of data conditioning and seismic interpretation techniques can be used to enhance the visualisation of channelized and non-channelized fluvio-deltaic deposits in the subsurface. Frequency decomposition (and the making of colour-blended volumes) allows the visualisation of the detail of channel belt deposits such as channel belt migration and lateral accretion deposits. Allogenic processes, particularly base-level (buttress) rise and fall have been shown to exert a control on the overall stacking pattern of the studied fluvio-deltaic deposits, whereas autogenic processes are interpreted as the major control on the local arrangement and architecture of channel belt and overbank deposits. The first study in this thesis uses the Upper Permian Rangal Coal Measures, a large-scale fluvial system, which accumulated in a foreland basin setting in the Bowen Basin, Queensland, Australia. The study investigates the architecture and connectivity of splay and distributary channels. The second study uses the Late Triassic Mungaroo Formation, a Mississippi-scale fluvio-deltaic system with a fluvially-dominated, tidally-influenced delta, which accumulated in the Northern Carnarvon Basin, Northwest Shelf, Australia. The study investigates different seismic interpretation techniques and investigates the relative control on fluvio-deltaic deposition of allogenic and autogenic processes.

Thesis advisor: Douglas Edmonds
Due to their low-lying position near the shoreline, river deltas are vulnerable to fluctuations in relative sea-level (RSL). Moreover, relatively little is known about fluvio-deltaic dynamics during RSL fall because the resulting deposits have low preservation potential. In this paper, I present a field-based study of the Goose River delta, coupled with numerical model simulations, that investigates the fluvio-deltaic response to RSL fall. The Goose River delta is a sandy fjord delta at the mouth of the Goose River located at the western end of Lake Melville, an inlet of the Labrador Sea, Canada and has experienced a RSL fall of 3 to 6 mm/yr in the past 5000 years due to post-glacial isostatic rebound. Aerial images show three abandoned delta lobes and one active lobe, suggesting that avulsions and lobe-switching occurred during RSL fall. Elevation analysis using Shuttle Radar Topography Mission (SRTM) digital elevation model (DEM) data and optically-stimulated luminescence (OSL) dating suggest that a series of downstepping terraced delta lobes formed at the mouth of the Goose River during a period of RSL fall. Similarly, Delft3D model runs show continued avulsions and formation of multiple terraced delta lobes deposited at progressively lower elevations. I show computationally that by decreasing delta lobe widths, deltas may remain aggradational during RSL fall, creating conditions favorable for lobe-switching during RSL fall. Observations from the field and model runs provide a critical link in understanding the geomorphic processes occurring during RSL fall, and in particular show that 1) incision and sediment bypass is not a necessary response to RSL fall and 2) lateral migration of a delta via avulsion can continue to occur with falling sea-level
Thesis (MS) — Boston College, 2013
Submitted to: Boston College. Graduate School of Arts and Sciences
Discipline: Geology and Geophysics

Incorporating improved preparation techniques, modern taxonomy, and quantitative analysis of environmental variables known to influence marsh foraminifers in other coastal regions refined marsh foraminiferal biofacies of the Mississippi delta region. Elevation, pore water salinity, total carbon, and mean grain size were compared with foraminiferal distributions in a transgressive marsh system of the lower Lafourche headland of the south-central delta plain. Cluster analysis aided definition of two biofacies, one from the marsh interior and one from the marsh edge. The marsh edge biofacies was further subdivided into levee crest and bayou margin biofacies. Correlation analysis suggested that seven of the 21 most common foraminifers correlated significantly with physical variables. Juvenile Trochammina inflata correlated with salinity; Ammotium crassus and Ammonia parkinsoniana correlated with elevation; Polysaccammina ipohalina and Miliammina fusca correlated with grain size; and Miliammina fusca correlated with organic carbon. The trends are consistent with relationships observed in many other coastal regions.

A Artrite Idiopática Juvenil (AIJ) abrange um grupo de doenças caracterizadas pela inflamação crônica sinovial com densa infiltração de linfócitos T. É uma das mais prevalentes entre as doenças reumáticas crônicas da infância, podendo acarretar incapacidade motora permanente. Não é conhecido fator causal até o momento. Há evidências da ação imunológica pela confirmação da elevação dos níveis séricos e no líquido sinovial de interleucinas e receptores de interleucinas tais como IL-6 e TNFα. Um receptor que está sendo associado ao estabelecimento do processo inflamatório nas doenças auto-imunes é o receptor de quimiocinas CCR5. As quimiocinas são moléculas pró-inflamatórias que funcionam através da ativação e atração química dos leucócitos. Elas exercem atividade quimiotática sobre neutrófilos, linfócitos e monócitos, tendo papel importante em todas as fases da inflamação. A variante polimórfica CCR5delta32 está descrita como protetora contra infecções por HIV-1 e doenças como Artrite Reumatóide (AR), mas há poucos estudos na AIJ. O objetivo deste estudo foi avaliar a associação da variante polimórfica delta32 do receptor de quimiocinas CCR5 com a Artrite Idiopática Juvenil e com seus subtipos oligoarticular, poliarticular e sistêmico. Trata-se de um estudo caso-controle com 101 pacientes que completaram critérios de AIJ oligoarticular, poliarticular e sistêmico, e 104 indivíduos saudáveis, caucasóides, acima de 16 anos, pareados por sexo. O DNA foi extraído e genotipado para a presença do alelo CCR5delta32 por reação em cadeia da polimerase. O teste de Qui-quadrado foi usado para comparar as diferenças entre as freqüências das variantes alélicas. Entre os 101 pacientes, 80 eram do sexo feminino (79,2%); a média de idade do início da doença foi 4,8 anos + 3,1; a média de tempo de doença foi 5 anos +2,6. A presença do alelo CCR5delta32 foi mais elevada nos pacientes com AIJ (9,4%; P=0,049) e no subtipo sistêmico (25%; P=0,004) em comparação com o grupo controle (4%), enquanto não houve diferença nos subtipos oligoarticular (4%; P=0,757) e poliarticular (10%; P=0,071). Este estudo permitiu concluir que a freqüência do alelo CCR5delta32 foi maior em pacientes com AIJ e em pacientes com o subtipo sistêmico, e semelhante aos controles nos pacientes com os subtipos oligoarticular e poliarticular. Os resultados também sugerem a existência de diferença na susceptibilidade genética e imunopatológica entre os subtipos de AIJ.
The Juvenile Idiopathic Arthritis (JIA) includes a group of diseases characterized by chronic synovial inflammation with dense T lymphocyte infiltration. It is one of the most prevalent among the rheumatic chronic diseases of the childhood, and could lead to permanent motive inability. There is not causal factor identified until the moment. There are evidences of the immunological action through the elevation of cytokine blood serum levels and interleukins receptor such as IL-6 and TNF. A receptor that is being associated to the establishment of the inflammatory process in auto-immune diseases is the chemokine receptor CCR5. Chemokines are pro-inflammatory molecules that act through the activation and chemoattraction of the leucocytes. They exercise chemotatic activity on neutrophyls, lymphocytes and monocytes and develop important functions in all phases of the inflammation. The polymorphic variant CCR5delta32 was described as protective against infections for HIV-1 and diseases as Rheumatoid Arthritis (RA), but there are few studies in JIA. The objective of this study was to evaluate the association of the polymorphic variant delta32 of the chemokine receptor CCR5 and Juvenile Idiopathic Arthritis subtypes: polyarticular, oligoarticular and systemic. It is a case-control study with 101 patients that fulfilled the criteria of oligoarticular, polyarticular and systemic JIA, and 104 healthy, caucasian individuals, above 16 years old, matched by gender. The DNA was extracted and genotyped for the presence of the CCR5delta32 allele by polimerase chain reaction. The Chi-square test was used to compare the differences among the frequencies of the allelic variants. Among the 101 patients, 80 were female (79,2%); the average of age on the beginning of the disease was 4,8 years + 3,1; the average of time of disease was 5 years + 2,6. The largest frequency of the CCR5delta32 allele was statistically significant in the patients with JIA (9,4%; P=0,049) and the subtype systemic arthritis (25%; P=0.004) as compared to the controls, while there was not difference between the oligoarticular (5%; P=0,757) and polyarticular subtypes (10%; P=0.071) and controls (4%). This study allowed concluding that the frequency of the CCR5delta32 allele was higher in patients with JIA and subtype systemic, and similar to the controls in the patients with oligoarticular and polyarticular subtypes. The result also suggests the existence of difference in the genetic immunopathologic susceptibility among the JIA subtypes.

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Os isótopos estáveis vêm sendo utilizados há várias décadas em estudos com animais ruminantes pelo motivo dos valores isotópicos terem como base os alimentos assimilados e não apenas os alimentos ingeridos. O presente estudo teve por objetivo determinar o valor isotópico do 15N e composição bromatológica em condições naturais do capim-marandu (Urochloa brizantha cv. Marandu), sob o diferimento em função da adubação utilizada, em quatro cortes após a vedação. O trabalho foi desenvolvido na Faculdade de Medicina e Veterinária e Zootecnia da UNESP de Botucatu. A área, 576m2, utilizada para as parcelas foi dividida em 3 tratamentos com 4 repetições cada, segundo os tratamentos: T1 - tratamento testemunho sem adubação; T2 – adubação orgânica sintética com ureia e T3 – adubação orgânica com cama de frango. Após três meses, o capim foi cortado a cada 15 dias, totalizando 4 períodos de vedação. As amostras colhidas no experimento foram analisadas em relação ao sinal isotópico do nitrogênio e composição bromatológica de proteína bruta, fibra em detergente neutro, fibra em detergente ácido, celulose, hemicelulose e lignina. A degradação do adubo cama de frango, pelo método do litter bag, foi analisada por meio da regressão. Existe diferença para 15N na forragem em relação os tratamentos utilizados, assim como para porcentagem de Nitrogênio na forragem, porcentagem de Nitrogênio Total na Folha, 15N na folha, 15N no perfilho. Para o efeito coleta houve diferença para %Nitrogênio Total, %N total na folha, %N total no colmo e % N total no perfilho. Para análise de Proteína Bruta, houve diferença entre tratamentos, porém quando analisadas as coletas, houve duas variáveis que tiveram diferença, proteína bruta e lignina. A técnica dos isótopos estáveis do N foi eficaz na discriminação da adubação inorgânica e orgânica na pastagem de ...
Stable isotopes have been used for decades in studies with ruminant animals by reason of isotopic values are based upon not only assimilated food and food eaten. The present study aimed to determine the value of 15N isotopic and chemical composition in natural conditions Marandugrass (Urochloa brizantha. Marandu) under the deferral according to the fertilization used in four cuts after sealing. The work was conducted at the College of Medicine and Veterinary Medicine and Animal Science, UNESP Botucatu. The area, 576m2, used for plots was divided into 3 treatments with 4 replicates each, according to the treatments: T1 - testimony treatment without fertilization; T2 - synthetic organic fertilization with urea and T3 - organic fertilization with poultry litter. After three months, the grass was cut every 15 days, totaling 4 blackout periods. Samples collected in the experiment were analyzed for nitrogen isotopic and chemical composition of crude protein, neutral detergent fiber, acid detergent fiber, cellulose, hemicellulose and lignin. The degradation of poultry litter compost, by the litter bag method was analyzed by regression. Is there a difference for 15N forage compared the treatments, as well as percentage of nitrogen in the forage, percentage of Total Nitrogen in leaf, the leaf 15N, 15N the tiller. To effect the collection was no difference in % Total Nitrogen, % of total N in leaf % N content in stem and % of total N in the tiller. For analysis of crude protein, significant difference between treatments, but when analyzed collections, there were two variables that had differences, crude protein and lignin. The technique of stable isotopes of N was effective in discriminating the inorganic and organic fertilizer on pasture Urochloa brizantha. Marandu deferred and the chemical composition, the source of N did not affect forage quality.

Orientador: Carlos Ducatti
Coorientador : Paulo Roberto de Lima Meirelles
Banca: Ciniro Costa
Banca: Ricarda Maria dos Santos
Banca: Roberto Lyra Villas Boas
Resumo: Os isótopos estáveis vêm sendo utilizados há várias décadas em estudos com animais ruminantes pelo motivo dos valores isotópicos terem como base os alimentos assimilados e não apenas os alimentos ingeridos. O presente estudo teve por objetivo determinar o valor isotópico do 15N e composição bromatológica em condições naturais do capim-marandu (Urochloa brizantha cv. Marandu), sob o diferimento em função da adubação utilizada, em quatro cortes após a vedação. O trabalho foi desenvolvido na Faculdade de Medicina e Veterinária e Zootecnia da UNESP de Botucatu. A área, 576m2, utilizada para as parcelas foi dividida em 3 tratamentos com 4 repetições cada, segundo os tratamentos: T1 - tratamento testemunho sem adubação; T2 - adubação orgânica sintética com ureia e T3 - adubação orgânica com cama de frango. Após três meses, o capim foi cortado a cada 15 dias, totalizando 4 períodos de vedação. As amostras colhidas no experimento foram analisadas em relação ao sinal isotópico do nitrogênio e composição bromatológica de proteína bruta, fibra em detergente neutro, fibra em detergente ácido, celulose, hemicelulose e lignina. A degradação do adubo cama de frango, pelo método do litter bag, foi analisada por meio da regressão. Existe diferença para 15N na forragem em relação os tratamentos utilizados, assim como para porcentagem de Nitrogênio na forragem, porcentagem de Nitrogênio Total na Folha, 15N na folha, 15N no perfilho. Para o efeito coleta houve diferença para %Nitrogênio Total, %N total na folha, %N total no colmo e % N total no perfilho. Para análise de Proteína Bruta, houve diferença entre tratamentos, porém quando analisadas as coletas, houve duas variáveis que tiveram diferença, proteína bruta e lignina. A técnica dos isótopos estáveis do N foi eficaz na discriminação da adubação inorgânica e orgânica na pastagem de ...
Abstract: Stable isotopes have been used for decades in studies with ruminant animals by reason of isotopic values are based upon not only assimilated food and food eaten. The present study aimed to determine the value of 15N isotopic and chemical composition in natural conditions Marandugrass (Urochloa brizantha. Marandu) under the deferral according to the fertilization used in four cuts after sealing. The work was conducted at the College of Medicine and Veterinary Medicine and Animal Science, UNESP Botucatu. The area, 576m2, used for plots was divided into 3 treatments with 4 replicates each, according to the treatments: T1 - testimony treatment without fertilization; T2 - synthetic organic fertilization with urea and T3 - organic fertilization with poultry litter. After three months, the grass was cut every 15 days, totaling 4 blackout periods. Samples collected in the experiment were analyzed for nitrogen isotopic and chemical composition of crude protein, neutral detergent fiber, acid detergent fiber, cellulose, hemicellulose and lignin. The degradation of poultry litter compost, by the litter bag method was analyzed by regression. Is there a difference for 15N forage compared the treatments, as well as percentage of nitrogen in the forage, percentage of Total Nitrogen in leaf, the leaf 15N, 15N the tiller. To effect the collection was no difference in % Total Nitrogen, % of total N in leaf % N content in stem and % of total N in the tiller. For analysis of crude protein, significant difference between treatments, but when analyzed collections, there were two variables that had differences, crude protein and lignin. The technique of stable isotopes of N was effective in discriminating the inorganic and organic fertilizer on pasture Urochloa brizantha. Marandu deferred and the chemical composition, the source of N did not affect forage quality.
Mestre

The Notch signalling pathway appears to be ubiquitous in metazoan animals, and is one of the most thoroughly studied signalling pathways. Notchmediated cell-cell communication is crucial for development: it governs the establishment of patterns of gene expression and differentiation and regulates binary cell fate choices and the maintenance of stem cell populations. In zebrafish, Notch signalling governs many aspects of embryonic and adult development and recent studies have identified the main players in different contexts. Interestingly, however, as we learn more about Notch signalling, we are starting to realize the complexity of this pathway that is put together in a relatively simple way. One source of complexity comes from the diversity of roles and functions of different Notch ligands. Among those, we are particularly interested in DeltaC and DeltaD, two major members of the Delta family of ligands, which are curiously expressed together in various contexts ranging from neurogenesis to formation of the gut epithelium and somitogenesis. Many questions remain as to the exact functions of the Notch ligands DeltaC and DeltaD in the somite segmentation process and elsewhere. To investigate temporal and other aspects of the role of these Notch ligands, I have created transgenic zebrafish lines in which we can provoke expression of either one with a heat shock, using either direct regulation by a heat-shock promoter or via GAL4-VP16. This thesis describes the work done during the creation, establishment and validation of these transgenic lines and discusses some of the applications that can reveal novel aspects of Notch signalling, focusing on somite segmentation. I believe that by using these transgenic fish lines, in coordination with other lines that we currently have, we will be able to answer important questions relevant to not only somite segmentation, but also Notch signalling in general.

The Pliocene-Recent Muda formation is essentially undeformed in the West Natuna Basin, and excellent resolution of this interval on three-dimensional seismic data in Belida Field allows detailed interpretation of component fluvial-deltaic systems. Detailed interpretation of seismic time slice and seismic sections along with seismic facies analysis, horizon mapping, and extraction of seismic attributes provide the basis to construct a sequence stratigraphic framework and determine patterns for sediment dispersal and accumulation. The Muda interval contains five third-order sequences, with depositional environments confined to the shelf and consisting mainly of fluvial elements. Sequence boundaries (SB) apparently result from major sea level falls, since there was no tectonic uplift and the field underwent only regional slow subsidence during sedimentation of the study interval. Sea level fluctuation also caused changes in fluvial patterns. Analysis of changing channel patterns indicates that major systems tracts relate to specific channel patterns. The Lowstand Systems Tract (LST) is generally dominated by larger channel dimensions and low sinuosity channel patterns. The Transgressive Systems Tract (TST) typically contains relatively smaller channels with high sinuosity. Channels in the Highstand Systems Tract (HST) generally show moderate sinuosity channels and are intermediate in size, larger than TST channels but smaller than LST channels. Crossplots of stratigraphic position and channel morphology indicate that within the transition from LST-TST, channel dimensions (width and thickness) generally decrease and channel sinuosity generally increases. High sinuosity, meandering and anastomosing channels are generally found near the maximum flooding surface. Low sinuosity channels occur within the HST-SB-LST succession, with the exception of higher sinuosity meandering channels evolving inside valleys. Larger, lower sinuosity channels result from high gradient and high discharge associated with stream piracy. Smaller, high-sinuosity channels result from low gradient and small discharge. Extraction of seismic attributes such as RMS Amplitude and Average Reflection Strength show these depositional features in greater detail. In the Belida Field area, lowstand channels were found to comprise the greatest volume of sandstone bodies. Seismic delineation of the distribution and morphology of these channel systems provides critical input for reservoir modeling and volumetric analysis.

Thesis (B. Sc.(Hons.))--University of Adelaide, National Centre for Petroleum Geology and Geophysics, 1996?
Volume 2 is boxed and consists of 1 folded map and 9 folded correlations. Includes bibliographical references (leaves 39-40).

Louisiana contains approximately 40 percent of the contiguous United States’ wetlands, and as much as 80 percent of America’s coastal land loss occurs there. This land loss is occurring at an astounding rate—a rate that is accelerating. The Mississippi River-Gulf Outlet (MRGO) is a 120-km- (75-mi-) long canal initially dredged in the 1950s and 1960s and maintained by the United States Army Corps of Engineers. It was intended to connect the Port of New Orleans directly to the Gulf of Mexico and bypass the time-consuming, tortuous route via the Mississippi River and Delta. Intially, environmental groups and citizens greatly opposed the MRGO as a potential ecological disaster. While in operation, the channel doubled and even tripled in width in some areas; it merged with Lake Borgne; it amplified storm surge, especially during Hurricanes Betsy and Katrina; and it caused saltwater intrusion in nearby wetlands and forests. Channel dredging ceased after Hurricane Katrina. In 2009, MRGO maritime traffic ended when a rock closure structure was installed. By comparing series of aerial photographs and satellite images, this study will summarize, highlight, and evaluate the land changes associated with the MRGO, with respect to its inland “Mile Markers.” Additionally, this study compares the roles of human activities versus natural processes in causing land loss in the MRGO area. Aerial photographs and satellite images of the MRGO also were compared and contrasted to see what is presently occurring at the channel concerning the closure structure. Lastly, possible solutions are offered for the mitigation of land loss and/or for creating new land area in the region.

Les mutations du gène LMNA, codant les lamines A/C, des protéines ubiquitaires de l'enveloppe nucléaire, sont responsables de formes autosomiques de dystrophie musculaire d'Emery-Dreifuss (EDMD), pathologie associant une atteinte des muscles squelettiques et une cardiomyopathie dilatée (DCM) avec troubles rythmiques et/ou conductifs. Lors de ma thèse j'ai analysé le phénotype musculaire et cardiaque de souris LmnaΔK32/+ (Het), mutation identifiée chez des patients présentant une EDMD sévère. Les souris Het n'ont pas d'atteinte musculaire mais développent une DCM conduisant au décès entre l'âge de 35 et 7O semaines. Le niveau de lamines A/C est diminué de 50% dans le cœur des souris Het avant et au début de la DCM mais similaire aux Wt chez les souris Het souffrant de DCM. La diminution de la quantité de lamines A/C est liée à leur dégradation par le système ubiquitine-protéasome (UPS) dont la fonction est altérée dans le cœur des souris Het, conduisant à l'augmentation de la quantité de lamines K32 avec l'âge. In vitro, l'accumulation des lamines A/C K32 conduit à leur agrégation nucléaire, suggérant un effet dominant négatif de ces protéines mutées. Pour conclure, la souris LmnaΔK32/+ est le premier modèle murin porteur d'une mutation du gène Lmna qui développe une cardiomyopathie isolée à l'état hétérozygote. L'UPS joue un rôle important dans la dégradation des lamines A/C mutées, limitant leur effet délétère. Les mécanismes physiopathologiques à l'origine de la DCM chez les souris Het sont donc doubles : à l'haploinsuffisance des lamines A/C, connue comme préjudiciable pour le cœur, s'ajoute un effet poison des lamines mutées augmentant avec la dysfonction de l'UPS

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plication designed to reduce the knowledge gap between classroom instruction and hands-on training onboard naval academy training boats (YPs). The goal was to develop a proof-of concept game-based simulator that uses 3D graphics to replicate basic tasks executed onboard the YPs. Two missions were selected for a brief task analysis study to determine the design of the respective game scenario and requirements. The design process involved in building user interface, physics model, 3D models, and artificial intelligence actors are described in this work. For thesis purposes, YPSim was designed using the Brazilian Naval Academy's YP as a training framework development environment. Using a sample of the final end user population, we conducted a user acceptance study of proof-of-concept version of YPSim (v0.14) at the Brazilian Naval Academy. The findings in this work can be generalized to any other naval academy or institution where basic navigation and shiphandling instruction is provided. Initial results from a prototype implementation of YPSim at the Brazilian Naval Academy provided insights into the potential use of this training system.

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The transport mechanism and deposition of sediments in deep water environments and their relationship with deltaic systems have captioned the attention of sedimentologists during the last decades due its importance as hydrocarbon reservoir. This work presents a comparative study of this kind of related deposits in two distinct areas with significant records of the Late Paleozoic glaciation of western Gondwana: (i) the well exposed deposits of Cerro Bola that belong to the Paganzo Group and (ii) the not so well exposed (but with potential economic interest) deposits of Rio do Sul Formation (Itararé Group) in Vidal Ramos, Paraná basin. Cerro Bola records 1000 m of sediment corresponding to five glacial/deglacial cycles; this work focuses on the relationship between the upper part of Cycle 3 and 4, corresponding to Upper Turbidites and Fluviodeltaic 3, respectively. Based on the sedimentary features here presented, the Fluviodeltaic 3 is re-interpreted as a sand-rich submarine fan in which the high sedimentation rates are interpreted as related to tectonic activity. The area of Vidal Ramos exposes~ 400 m of the Itararé Group. This research focuses on the upper part of Rio do Sul Formation, which records deltaic sediments dominated by gravity flows in the lower part. The upper part is characterized by a sandy delta front progradation associated with an increased sediment supply. The data presented in this work shows that the delta front deposits under conditions of slope instability generated gravity flows which are deposited as turbidites in the distal delta front/prodelta and is related to the effects of deglacial conditions and phases of increased sediment supply to deep water environments. The results indicate that the two areas are not directly comparable due to distinct depositional processes and paleogeographic configurations. The thick succession of sandstones in Cerro Bola is interpreted as turbidite fan controlled by tectonic activities in a deep basin context, while in Vidal Ramos the identified progradational sandy delta front is produced by a phase of increased sediment supply related to deglacial processes.

Cosmogenic ³²Si (t_1/2 ∼ 140 yrs) was used in a novel way to constrain the quantity of reactive Si storage and early diagenetic reactions of Si in the highly mobile deltaic sediments along the coast of French Guiana, representative of deposits along the ~1600 km Amazon–Guianas coastline downdrift of the Amazon delta. A sequential leach was developed to extract and purify SiO₂ from different operational pools in large samples of surface sediments (0–10cm). This methodology, a hot 1% Na₂CO₃ leach followed by a hot 4M NaOH leach, was adapted from the existing leaches widely used to estimate biogenic silica (bSi) content in marine sediments, and ultimately to constrain the global oceanic Si budget. ³²Si activity was determined in each pool via its daughter product ³²P. Results from several sites in coastal mudbanks near Kourou and Sinnamary indicate no detectable ³²Si activity in the bSi fraction, whereas ³²Si was detected in the Si-NaOH fraction after removal of bSi. The lack of detectable activity in the 1% Na₂CO₃ leach and its detection in the NaOH fraction (0.4–2.5 dpm) indicate that the method widely used to determine bSi content recovers only a minor fraction of the originally deposited reactive bSi in these deposits. The results are consistent with rapid alteration of biogenic silica and clay authigenesis or reverse weathering. They also demonstrate that the current estimate of biogenic silica storage in tropical deltaic sediments is significantly underestimated. Assuming an initial diatom specific activity range of ∼5–40 dpm/kg SiO ₂, the ³²Si activity in the NaOH fraction corresponds to a reactive Si storage of ∼150–18,000 µmol Si/g sediment. This magnitude is more consistent with estimates of reactive Si (ΣSi _hr) storage in the Amazon delta based on modified operational leach techniques that target poorly crystalline clays and with diagenetic modeling of pore water K⁺, F⁻, and Si(OH) ₄, though these modified leaches also appear to underestimate the amount of reactive Si stored along this system. To directly confirm whether these modified operational extractions underestimate reactive Si storage, a sequential extraction methodology was also developed to first isolate ³²Si activity in the ΣSi_hr fraction (0.1N HCl followed by 1% Na ₂CO₃) and then extract any remaining ³²Si from the residual fraction using 4M NaOH.

Sediment from 2 stations in the Gulf of Papua, Papua New Guinea, 1 station in the northern Gulf of Mexico near the Southwest Pass, and 1 station in Long Island Sound (Smithtown Bay) were also extracted for ³²Si in the bSi fraction as well as the residual fraction after removal of bSi. Bulk ³²Si activities in the residual fractions in the Gulf of Papua (0.5–0.7 dpm/kg sediment) were used to extrapolate Si storage in the outer topset and forset of the clinoform delta.

³²Si activity was detected in the both the bSi (0.21 ± 0.04 dpm/kg sediment) and the residual fraction (0.44 ± 0.08 dpm/kg sediment) from the site in the Gulf of Mexico. A Si burial rate using the ³²Si activity in the bSi fraction (assuming an activity of 15dpm/kg in starting Si materials) of 0.004Tmol/y was calculated over approximately 5000 km2 of the delta, whereas the burial rate calculated using the Si content in this same fraction from a classic bSi leach, was ∼0.006Tmol/y. Adding the Si burial rate using the ³²Si activity in the residual fraction (0.008Tmol/y) yielded a total storage per year of 0.012Tmol Si, ∼10% of the total Si inputs (dissolved and amorphous Si) from the Mississippi-Atchafalaya river system. ³²Si activity was also detected in the residual fraction (0.53 ± 0.08 dpm/kg sediment) after removal of ΣSi _hr and using this activity yielded similar calculated rates of Si burial (∼0.01 Tmol/y).

In Smithtown Bay, Long Island Sound, ³²Si activity was also detected in both the bSi (0.15 ± 0.05 dpm/kg sediment) and the residual (0.4 ± 0.2 dpm/kg sediment) fractions from the site in Smithtown Bay, Long Island Sound, yielding a total Si storage estimate (assuming an activity of 15 dpm/kg in starting Si materials) of 1.6 × 10⁻³ Tmol/y over the entire Sound, comparable to estimates of Si storage calculated using the Si content in the classic bSi (1.1 × 10 ⁻³ Tmol/y) and the classic ΣSi_hr (2.2 × 10⁻³ Tmol/y) leaches. It appears that reverse weathering is an important sink of Si in these deposits and that classic bSi or ΣSi _hr leaches can underestimate Si storage in these system by two to four-fold. (Abstract shortened by UMI.)

The Azeri, Chirag and Gunashli (ACG) oilfield is located in the offshore Azerbaijan sector of the south Caspian Basin. This dissertation focuses on the Azeri Field which has over 8 billion barrels of oil in place. The major reservoir interval is the Pliocene Pereriv Suite, which is characterized by laterally continuous layers of variable net-to-gross (NTG) deposited in a fluvial-deltaic environment. The Azeri Field is being developed by both down-dip water injection and up-dip gas injection. This dissertation uses high-resolution models, derived from outcrop analogue and subsurface data, in conjunction with experimental design techniques, to rank the impact of different geological heterogeneities on recovery by both displacement mechanisms. Firstly, the impact of reservoir-unit scale heterogeneities on water and gas injection is assessed using a simplified fluids PVT description. At this level, the principal controls on oil recovery are the factors that affect sandbody connectivity and sweep efficiency. Secondly, the impact of reservoir- and genetic-unit scale heterogeneities on gas injection in high NTG intervals is assessed. The genetic-unit scale heterogeneities that control the approach to vertical equilibrium (VE) are found to be the principal controls on recovery. Their impact is large when gravity forces dominate the mobility unstable displacement, but decreases with increasing production rate as viscous forces dominate and the displacement moves out of VE. The presence of laterally extensive shales is also important, because they change the geometry of the reservoir layering and yields higher recovery than equivalent homogeneous models. The same rank order of key heterogeneities is obtained for simulations with simplified and a more realistic PVT description. Finally, the results are applied to develop a methodology to identifY the upper and lower boundaries on predicted recovery using a simple analytic approach that incorporates some geological heterogeneity.

Bengala passou por enormes experiências de desenvolvimento sócio‐cultural, de estabilidade económica e de avanço da literatura e das artes. Durante o reinado Budista, Hindu e do Sultanato, a sociedade foi‐se valorizando e enriquecendo com estes diferentes valores e a amálgama cultural que representaram. Esta coexistência foi evoluindo e as pessoas começaram a dedicar‐se ao comércio, mas foram organizando e reformando a própria sociedade. O verdadeiro "renascimento" desta política económica e cultural Bengali seguiu um determinado caminho entre os possíveis. Para se manter e para proteger o território dos inimigos e de todas as ameaças externas, os “heróis” antigos foram previdentes, desenvolvendo uma forte capacidade em reforçar território fortificado, que designamos por cidade‐fortaleza. Esta tipo de cidade histórica planeada foi implantada, com variações, neste delta Bengali; por isso, os padrões de instalação e ocupação antigos foram observados na sua relação com as margens ribeirinhas e os recursos de água adjacentes e centrados em torno de uma estrutura religiosa. Uma cronologia popular no país ajuda a compreender a formação de um povoado ou de uma cidade. Na era Budista, a comunidade religiosa, o bazar e as vias marítimas eram o ponto central que concentram a mistura de pessoas e nações. Este sítio não foi excepção do delta de Bengali, embora esta tese fosse sinuosa e estivesse no meio de uma grande rede fluvial; os antigos dirigentes face à necessidade de criar sistemas de protecção territorial foram gerando os diversos padrões de assentamento e ocupação, com mega‐estruturas, infraestruturas e uma arquitectura público que se foram tornando os elementos característicos do domínio do espaço. Essas fortalezas ribeirinhas foram organizando padrões de assentamento cujas características variavam em função das percepções estratégicas e da morfologia do sítio; afinal estas foram as cidades do Delta que, além do perfil do rio, muitas vezes dependeram de influências locais e tradicionais. Neste delta Bengal, a cidade podia obedecer a tipos diferentes, mas, no geral, havia um padrão geral de ocupação das cidades que os administradores budistas antigos concebiam com um planejamento estratégico e uma morfologia que ía além da muralha do forte. O objectivo desta investigação é, em primeiro lugar, identificar e analisar a morfologia das antigas cidades‐fortaleza e os padrões de assentamentos em termos das suas estratégias de defesa e da arquitectura que organizava a ligação ao rio da terra Bengali. Em segundo lugar, o contexto e a organização do planeamento e lugar das estruturas fortificadas, abordando‐as numa perspectiva de conjectura, através do trabalho pictográfico e ilustrado. O antigo assentamento e a própria arquitectura de MAHASTHAN, um sítio datado do século VIII AD é um local ideal para essa investigação, dado ser um local de memória, de um espaço evocativo, ter um "sentido de lugar" e, claro, um padrão espacial tradicional flexível em relação as condições regionais e às construção tradicionais deste delta Bengali. Por fim, o estudo irá explorar a imagem (restauração conjectural) da escala da cidade, do espaço, da função e do sentido cultural do próprio bairro da antiga povoação ribeirinha, através da revisão crítica da literatura, do conhecimento das sucessivas escavações arqueológicas e com a ajuda da informação histórica pictográfica. O estudo irá explorar ainda o significado desses antigos assentamentos no subcontinente e a sua transformação em Bengali, focando as estratégias actuais de defesa e a sua manifestação física, bem como o papel que pode ter o Património Digital; Riverine Fortress city of `MAHASTHAN´ in Deltaic Bengal: In search for the traditional settlement pattern of ancient cities Abstract: Bengal had passed through enormous experiences of socio‐cultural development, economical stabilities, advancement in literature and arts. During the reign of Buddhist, Hindu and Sultanate Bengal the society was cherished and enriched with full of values and cultural amalgamation. Co‐existence in the society evolved up and people started occupying time in trade‐transaction and society reformation. The ‘rebirth’ of the Bengali cultural consistency took a way forward to immense possible trails. To remain retain established and to protect the territory from external forces as well as the enemies, the ancient heroes had prepared themselves, besides invented with strong capability to reinforce fortified territory or the fortress city. The historic city planning implanted with different characteristics, and prolonged with variations in this delta land of Bengal. Ancient Bengal was focused with their settlement pattern by the bank of the river or by the watery sources. Settlement in the ancient time used to develop centering a religious structure. Eventually; it is the popular chronology for deriving a hamlet or a town. For the Buddhist era, religious community, bazaar and the maritime route came to focus with the mixture of various people and the nation. Simply, it was no exception for the case of the delta land Bengal, although this mainland is curved and chiseled with cress cross river networks; the ancient heroes contributed outposts for territorial protection and thoroughly generated the pattern of settlement. Mega structures, infrastructures and public welfare architecture were becoming the notion of the domain. That river fort architecture and the settlement patterns had the strategic and morphological characteristics, which got different from other purpose built forts, nonetheless‐was in consistence with the local city context. Bengali riverine fortress cities experienced lots of local and traditional influences only for being the river fort and their settlement around it, stating from the component, elements of forts and formal profile of the river. So, undoubtedly Bengal conceived unique kind of riverine oriented fortress settlement pattern, which has distinct typescripts. Even in the case of this fort formation the ancient Buddhist administrators had some strategic planning, morphology for spread city beyond the fort wall. The objective of the research is firstly to identify and to analyse the morphology of the ancient fortress cities1 and settlements in terms of their defence strategies and river fort architecture of Bengal. Secondly the context and the planning organization and positioning the sites for fortification addressing pictographic and conjectural restoration2 includes ancient city formation through river‐fort architecture in Bengal. The ancient settlement and architecture, dated back 8th Century AD of a specific site of MAHASTHAN would be the intensive area of the research, its memory, space, ‘sense of place’ and the traditional spatial pattern would be the intensive area of the study that would remind flexible towards regional conditions and building tradition as happened in riverine ancient Bengal. Lastly the study will explore the image (conjectural restoration) of the scale of the city, space, function and cultural longing of the neighbourhood pattern of ancient riverine settlement, through the critical literature reviewing, progressive archaeological excavation and by the referencing of historic pictographic information. The study will explore for meaning of ancient settlements in the subcontinent and its transformation in Bengal with a focus on defence strategies and its physical manifestation as well as the Digital Heritage phenomenon.