The carbon and oxygen isotopes of planktonic foraminifera, and faunal assemblages of towing samples, £_13C of dissolved inorganic carbon, and £_18O of seawater collected from northern South China Sea (SCS) were analyzed in this study. Plankton tows were collected between December 2002 and December 2005 at water depth of 100m. In addition, fauna and sea water samples were sampled at different depths ranging between 50 and 300m at some stations. Generally, the faunal assemblages are dominated by Globigerinoides ruber, Globigerinoides sacculifer, Globigerinoides aequilateralis, Pulleniatina obliquiloculata, Neogloboquadrina dutertrei, and Globorotalia menardii. G. aequilateralis and G. menardii are dominated in warm months while G. ruber, G. sacculifer, and P. obliquiloculata are dominated in cold months. The relative abundances of G. sacculifer and G. aequilateralis obtained from towing samples in this study are significantly higher than those shown in underlying sediment traps and surface sediments, suggesting that the tests of these two taxa are prone to dissolution. In addition, the abundance of P. obliquiloculata which serves as an index taxon for the Kuroshio Current in Paleoceanography, is more abundant in the northern part than in the southern part of the SCS basin. Nevertheless, the £_13C and £_18O of G. sacculifer and P. obliquiloculata are significantly lighter than that in sediment traps and surface sediments, indicating some potential effects caused by the differential dissolution. Possible dwelling depths of P. obliquiloculata is estimated between 50 and 90m, whereas N. dutertrei is estimated between 20 and 80m according to Kim and O¡¦Neil (1997). The latter changes to 40~160m when the equation of Bouvier-Soumagnac and Duplessy (1985) is applied. Oxygen isotope compositions of G. sacculifer and G. ruber display a significant correlation with temperature (T) in the surface mixed layer. The slopes of £_18O/ T for these two species are similar to each other. The differences of £_18O (£G£_18O) between G. sacculifer and N. dutertrei, G. sacculifer and P. obliquiloculata, G. ruber and P. obliquiloculata are proved to be a good proxy indicator for reconstructing the upper water column based on the statistic relationship between £G£_18O and £GT (difference between mixed layer and 100m) in this study.

Submitted by Fabio Sobreira Campos da Costa (fabio.sobreira@ufpe.br) on 2016-07-26T12:44:17Z No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Dissertação Versão Biblioteca - ImprimirOK.pdf: 2780004 bytes, checksum: 26f8b7cae86c9fabc567061fe899162f (MD5) / Made available in DSpace on 2016-07-26T12:44:17Z (GMT). No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Dissertação Versão Biblioteca - ImprimirOK.pdf: 2780004 bytes, checksum: 26f8b7cae86c9fabc567061fe899162f (MD5) Previous issue date: 2016-01-18 / CAPEs / A pesquisa foi realizada no estuário do rio Goiana - PE (7º20’S/34º50’W) e objetivou compreender a influência dos processos naturais e antrópicos na sedimentação atual e biogeoquímica na área. Foram coletadas 23 amostras de sedimentos superficiais em Fevereiro/2012 (região do baixo e médio estuário) e realizadas análises granulométricas, de matéria orgânica total (MOT), carbono orgânico total (COT), nitrogênio total (NT), Carbonato de cálcio (CaCO3), razão C/N e razões isotópicas de δ¹³C e δ¹⁵N. Como análises complementares foram realizadas as análises da fração arenosa e o índice BPN (Bio Production Number) para a determinação do estado trófico do ambiente. Foram executadas também análises de correlação (Spearman), componentes principais e agrupamento (Cluster). Os sedimentos foram classificados como heterogêneos com predomínio de areias-sílticas siliciclásticas, pobremente selecionadas com baixos a médios teores orgânicos e de origem mista. As análises de correlação indicaram significância entre os teores de CaCO3 e MOT (rs=0,67; p<0,05), ao contrário dos dados de MOT e COT (rs=0,06; p>0,05). A distribuição destes parâmetros não estabeleceu variações diretas com a granulometria. Concomitantemente a isso, o cálculo BPN evidenciou a condição predominante de hipertrofia, com os maiores índices nas estações de coleta adjacentes às áreas de carcinocultura, indicando que a presente distribuição sedimentar apresenta anomalias diretamente relacionadas ao aporte externo de contaminantes, evidenciando assim, a ocorrência de influências resultantes de atividades agrícolas, agropecuárias e/ou atividades cimenteiras exercidas na região, comportamento já reportado na literatura em outras regiões. / The study site is the Goiana River estuary–PE (7º20’S/34º50’W) and this research aims to understand the influence of natural and anthropogenic processes on modern sedimentation and biogeochemistry in the area. Twenty-three sediment samples were collected in Feb/2012 (in middle and lower estuary) and analyses of grain size, total organic matter (TOM), total organic carbon (TOC), total nitrogen (TN), C/N ratio, CaCO3 and δ¹³C-δ¹⁵N isotopic ratios. Were performed the coarse fraction analisys and the BPN index to determine the environmental trophic state. The collection data were treated by mean of the correlation analysis (Spearman), main components and groups (Cluster). The sediments were classified as heterogeneous, with mainly siliciclastic siltic-sand, poorly sorted varying from low to medium organic contents and presenting mixed origin. There was significant correlation between levels of CaCO3 and TOM (rs=0.67; p<0.05), unlike the data TOM and TOC (rs=0.06; p> 0.05). The distribution of these parameters does not establish direct variations with the grain size. Concurrently, the BPN index showed the predominant hypertrophy condition, with higher values located in sampling stations adjacent to shrimp farming areas. This indicates that this sediment distribution presents anomalies directly related to the allochthonous input of contaminants, thus evidencing the influences from agricultural activities, aquaculture and/or cement activities in the surrounding area. This behavior were already reported in the literature in other regions.

Rice grows in saturated soil water condition and its requirement for water is highest amongst other cereal crops. In India, the southwest monsoon wind regime brings rainfall that provides a favourable environment for rice cultivation. Thus, there is significant dependency ofrice production on the southwest monsoon rainfall. Being a crop that grows across diverse climatic regions in India ranging from the humid to semi-arid, it offers possibility to explore therelationship between stable isotopic compositions in the grain organic matter with the climaticfactors relevant for its growth. In this thesis, we measured the isotopic compositions of oxygen, hydrogen and carbon of several rice genotypes that were cultivated during the southwest monsoon in diverse climatic regions across the Indian landmass. These isotopic values were then compared with the seasonalaverage values of climate factors such as relative humidity and temperature. Together with thiswe also studied the dependency of the oxygen isotope composition of the grain OM (δ18OOM) onthat of the source water (δ18OSW). Upon removal of δ18OSW effect from δ18OOM, we obtained astrong and significant relationship between the 18O enrichment in grain organic matter (definedas 18OOM) with relative humidity. The gradient recorded was 0.45‰ shift in 18OOM with 1%change in the relative humidity level. This relationship can potentially be used to estimate thepast variations in relative humidity (and by extension, can provide a measure of monsoon rainfallvariations). We further validated this relationship based on experiments carried out in aglasshouse where all the physical factors were well-monitored. Together with this, carbonisotopic composition measured in the rice grain organic matter were used to infer the water useefficiency of rice grown in different climatic settings. The stable isotope approach was furtherimplemented for studying the archaeological rice grains recovered from archaeological sites. Analysis of carbon isotopic composition of archaeological rice grains from seven archaeologicalsites (Balu, Kanmer, Ojiyana, Lahuradewa, JognaKhera, Hulas and Kunal), belonging to theHarappan civilization and other contemporary cultures provided a new suit of data on quantitativeestimate of the hydroclimatic condition (specifically relative humidity) and water availabilityduring the existence of this civilization.

Rice grows in saturated soil water condition and its requirement for water is highest amongst other cereal crops. In India, the southwest monsoon wind regime brings rainfall that provides a favourable environment for rice cultivation. Thus, there is significant dependency ofrice production on the southwest monsoon rainfall. Being a crop that grows across diverse climatic regions in India ranging from the humid to semi-arid, it offers possibility to explore therelationship between stable isotopic compositions in the grain organic matter with the climaticfactors relevant for its growth. In this thesis, we measured the isotopic compositions of oxygen, hydrogen and carbon of several rice genotypes that were cultivated during the southwest monsoon in diverse climatic regions across the Indian landmass. These isotopic values were then compared with the seasonalaverage values of climate factors such as relative humidity and temperature. Together with thiswe also studied the dependency of the oxygen isotope composition of the grain OM (δ18OOM) onthat of the source water (δ18OSW). Upon removal of δ18OSW effect from δ18OOM, we obtained astrong and significant relationship between the 18O enrichment in grain organic matter (definedas 18OOM) with relative humidity. The gradient recorded was 0.45‰ shift in 18OOM with 1%change in the relative humidity level. This relationship can potentially be used to estimate thepast variations in relative humidity (and by extension, can provide a measure of monsoon rainfallvariations). We further validated this relationship based on experiments carried out in aglasshouse where all the physical factors were well-monitored. Together with this, carbonisotopic composition measured in the rice grain organic matter were used to infer the water useefficiency of rice grown in different climatic settings. The stable isotope approach was furtherimplemented for studying the archaeological rice grains recovered from archaeological sites. Analysis of carbon isotopic composition of archaeological rice grains from seven archaeologicalsites (Balu, Kanmer, Ojiyana, Lahuradewa, JognaKhera, Hulas and Kunal), belonging to theHarappan civilization and other contemporary cultures provided a new suit of data on quantitativeestimate of the hydroclimatic condition (specifically relative humidity) and water availabilityduring the existence of this civilization

Rice grows in saturated soil water condition and its requirement for water is highest amongst other cereal crops. In India, the southwest monsoon wind regime brings rainfall that provides a favourable environment for rice cultivation. Thus, there is significant dependency ofrice production on the southwest monsoon rainfall. Being a crop that grows across diverse climatic regions in India ranging from the humid to semi-arid, it offers possibility to explore therelationship between stable isotopic compositions in the grain organic matter with the climaticfactors relevant for its growth. In this thesis, we measured the isotopic compositions of oxygen, hydrogen and carbon of several rice genotypes that were cultivated during the southwest monsoon in diverse climatic regions across the Indian landmass. These isotopic values were then compared with the seasonalaverage values of climate factors such as relative humidity and temperature. Together with thiswe also studied the dependency of the oxygen isotope composition of the grain OM (δ18OOM) onthat of the source water (δ18OSW). Upon removal of δ18OSW effect from δ18OOM, we obtained astrong and significant relationship between the 18O enrichment in grain organic matter (definedas 18OOM) with relative humidity. The gradient recorded was 0.45‰ shift in 18OOM with 1%change in the relative humidity level. This relationship can potentially be used to estimate thepast variations in relative humidity (and by extension, can provide a measure of monsoon rainfallvariations). We further validated this relationship based on experiments carried out in aglasshouse where all the physical factors were well-monitored. Together with this, carbonisotopic composition measured in the rice grain organic matter were used to infer the water useefficiency of rice grown in different climatic settings. The stable isotope approach was furtherimplemented for studying the archaeological rice grains recovered from archaeological sites. Analysis of carbon isotopic composition of archaeological rice grains from seven archaeologicalsites (Balu, Kanmer, Ojiyana, Lahuradewa, JognaKhera, Hulas and Kunal), belonging to theHarappan civilization and other contemporary cultures provided a new suit of data on quantitativeestimate of the hydroclimatic condition (specifically relative humidity) and water availabilityduring the existence of this civilization.

O objetivo desta tese é reconhecer as feições morfológicas e compreender o empilhamento de fácies deixado em sub-superfície como registro da evolução holocênica da retrobarreira entre Jaguaruna e Laguna (Santa Catarina, Sul do Brasil). Esta retrobarreira é formada por quatro setores geográficos, de SW para NE: Garopaba do Sul, Camacho, Rio do Meio e Campos Verdes. O setor de Garopaba do Sul, no contexto geomorfológico, difere dos demais pela presença, no limite interno, de terraço marinho pleistocênico, em parte recoberto por paleodunas pré-máxima inundação holocênica (geração eólica 2), e por abranger lago residual do sistema lagunar (Laranjal). As idades \'ANTPOT.14 C\' encontradas variam entre 5560 a 2190 anos cal A.P.. A sucessão de fácies deposicionais caracteriza-se por três associações de fácies: lagunar, planície de maré e eólica. No setor Camacho, porção central e de máximo estreitamento da barreira, a principal diferença morfológica são os paleodeltas de maré enchente associados á mingração do canal lagunar Camacho para NE. Nos depósitos, foram encontradas idades entre 8185 e 2165 anos cal A.P. e delimitadas quatro associações de fácies: desembocadura lagunar, delta de maré enchente, planície de maré e eólica. No setor Rio do Meio, a retrobarreira atua como planície interlagunar, separando a laguna Camacho (a SW) da laguna Santa Marta (para NE). Esta planície posiciona-se à retaguarda dos costões rochosos Ponta do Ilhote Pequeno e Cabo de Santa Marta, onde se originou a partir da formação de um tômbolo. Corresponde ao setor de maior influência continental pela frente deltaica do rio Tubarão, com três associações de fácies deposicionais: tômbolo, lagunar e planície de maré. As idades \'ANTPOT.14 C\' nas duas últimas associações variam entre 4650 e 1850 anos cal A.P.. Em Campos Verdes, a retrobarreira é formada por alinhamento de cordões litorâneos transversais à costa atual, separados entre si por truncamentos em padrão côncavoconvexo. Parte dos cordões superpõe-se por campos de paleodunas parabólicas atribuídas à geração eólica 3 (pós-máxima inundação). Neste setor, encontram-se três associações de fácies: pontal lagunar, cordões litorâneos e dunas eólicas. A análise integrada dos resultados permitiu diferenciar três fases evolutivas na retrobarreira. A Fase 1, entre 8000 e 5000 anos cal A.P. abrange o período de progressiva elevação e de mais alto nível do mar. A influência marinha na Fase 1 é evidenciada nos depósitos da retrobarreira com abundante concentração de conchas (inteiras e fragmentadas) de sistemas marinhos e lagunares/baía; a matéria orgânica preservada nos sedimentos apresentou valores de \'delta\'\'POT.13\'C entre -19 e -22%o , típicos de fitoplâncton marinho; a variação isotópica em conchas, com valores de \'delta\'\'POT.13\'C entre 1,22%o e 0,20%o e de \'delta\'\'POT.18\'O de - 0,5%o a - 1,8%o , indica o predomínio da dinâmica sedimentar marinha durante a fase 1. Interpretou-se que na Fase 1 a área de estudo foi ocupada por extenso sistema baía, com vales incisos afogados e ilhas emersas (representadas pelos atuais costões rochosos de Ponta do Ilhote Pequeno, Cabo de Santa Marta e Ponta da Galheta). Com a formação da barreira a baía isolou-se do mar raso, dando lugar ao corpo de água lagunar mixoalino. Na Fase 2, de 5000 a 3000 anos cal A.P., sob condições de NRM declinante, observou-se o desenvolvimento sedimentar diferenciado dos quatro setores retrobarreira, condicionado pela morfologia preexistente e pelo suprimento sedimentar. Os depósitos da Fase 3, de cerca de 3000 anos A.P. ao atual, caracterizam-se por: ausência de conchas, predomínio de fácies de areia fina com detritos vegetais, aumento ascendente dos valores de \'C IND.org\' e queda da razão \'delta\'\'POT.13\'C em sedimentos, alcançando valores típicos de plantas C3 e C4. Durante esta fase, a disponibilidade de sedimentos pela progradação da frente deltaica sobre a margem lagunar, associada à continuidade da queda de NRM, acelerou o assoreamento e a emersão das feições lagunares. Estas passaram a ser remodeladas pela circulação lagunar intermarés, o que determinou seu recobrimento pelas marismas e pântanos de maré. A Fase 3 pode ser considerada como de máxima estabilização das dunas eólicas, com formação de extensa planície de deflação e interdunas alagadas. Atesta-se assim a redução da influência de águas marinhas, possivelmente associada a alongamento, restrição ou mesmo fechamento da desembocadura lagunar, com aumento relativo do aporte de matéria orgânica continental. / The aims of this thesis is to identify the morphological features and understand the facies succession of the Holocene backbarrier in the Jaguaruna-Laguna region (Santa Catarina, Brazil). This backbarrier is formed by four geographic sectors, from SW to NE: Garopaba do Sul, Camacho, Rio do Meio and Campos Verdes. Regarding the geomorphological context, the sector of Garopaba do Sul differs from the others by the existence of a Pleistocene marine terrace, which is partly covered by paleodunes (generation 2) pre-maximum Holocene relative sea level (RSL), and by the presence of a residual lake of the lagoon system (Laranjal Lake). The depositional facies succession shows radiocarbon ages between 5560 and 2190 cal yr BP, being characterized by three facies associations: lagoonal, tidal flat and aeolian. The backbarrier of Camacho is sited beside the narrowest part of the barrier. Its main morphologic features are flood tidal paleodeltas associated with the migration of the Camacho inlet toward NE. Four facies associations were defined in this sector, with ages between 8185 and 2165 cal yr BP: inlet, flood-tidal delta, tidal plain and aeolian. At Rio do Meio, the backbarrier consists in an tidal flat separating the Camacho lagoon (SW) from the Santa Marta lagoon (NE).This plain is located rearward from Ponta do Ilhote Pequeno and Cabo de Santa Marta, where it was originated from the formation of a tombolo separating the two lagoons. It is also the sector with greater influence of Tubarão river deltaic front. Three facies associations were recognized: tombolo, lagoonal and tidal flat. The \'ANTPOT.14 C\' ages obtained in lagoonal deposits vary between 5570 and 1850 cal yr BP. In Campos Verdes, the backbarrier is formed by sets of beach ridges alignments, oriented transversal to the coastline and separated from each other by concave-convex truncations. Part of the ridges are superposed by several inactive parabolic dune-fields, attributed to the aeolian generation 3 (post maximum Holocene flooding).This sector is formed by three facies association: lagoon spit, beach ridges and aeolian dunes. The multi-proxy analysis of the set of results enabled the differentiation of three evolutionary phases in the backbarrier. The Phase 1, from 8000 to 5000 cal yr BP, comprises the period of progressive elevation and highest relative sea-level. The marine influence in this Phase 1 is recorded by abundant shells and shell fragments from invertebrates that live in marine and lagoonal/bay environments; the organic matter preserved in the sediments show \'delta\'\'POT.13\'C inside the interval between -19 and -22%o which is typical of marine phytoplanktons; in the shells, the vertical variation of \'delta\'\'POT.13\'C (from 1.22%o to 0.20%o) and \'delta\'\'POT.18\'O (from -0.5%o to -1.8%o) indicates the influence of marine in this Fase 1. This led to the conclusion that in this Phase 1, the survey area should be occupied by an extensive bay system, with drowned incised valleys and isolated islands (represented by the current Ponta do Ilhote Pequeno, Cabo de Santa Marta and Ponta da Galheta). With fhe formation of the barrier the bay was separated from the shallow open sea, giving place to the lagoonal mixohaline water body. During Phase 2, from 5000 to 3000 years cal BP, under declining sea-level conditions, the four backbarrier sectors experienced different sedimentary evolutions, conditioned by the pre-existing morphology and sedimentary supply of each one. The deposits of the Phase 3, from around 3000 years BP to the present, are characterized by: absence of shells, predominance of fine sand facies with plant debris, increasingly higher amounts of \'C IND.org\' and lower \'delta\'\'POT.13\'C ratio in sediments, which begin to record values typical of C3 and C4 plants. This phase is interpreted as resulting from the progradation of the delta front on the lagoon margin, combined with the continued reduced sea level, accelerated filling process and emersion of lagoonal features. These features were remodeled by the lagoonal circulation, determining the recovering by tidal marshes. Phase 3 can also be considered as the maximum stabilization of aeolian dunes, with the formation of an extensive deflation plain and wet interdunes. This reducing of marine influence is potentially associated with the stretching, limitation or even closing of the lagoon mouth, with relative increase in the accumulation of continental organic matter.

O objetivo desta tese é reconhecer as feições morfológicas e compreender o empilhamento de fácies deixado em sub-superfície como registro da evolução holocênica da retrobarreira entre Jaguaruna e Laguna (Santa Catarina, Sul do Brasil). Esta retrobarreira é formada por quatro setores geográficos, de SW para NE: Garopaba do Sul, Camacho, Rio do Meio e Campos Verdes. O setor de Garopaba do Sul, no contexto geomorfológico, difere dos demais pela presença, no limite interno, de terraço marinho pleistocênico, em parte recoberto por paleodunas pré-máxima inundação holocênica (geração eólica 2), e por abranger lago residual do sistema lagunar (Laranjal). As idades \'ANTPOT.14 C\' encontradas variam entre 5560 a 2190 anos cal A.P.. A sucessão de fácies deposicionais caracteriza-se por três associações de fácies: lagunar, planície de maré e eólica. No setor Camacho, porção central e de máximo estreitamento da barreira, a principal diferença morfológica são os paleodeltas de maré enchente associados á mingração do canal lagunar Camacho para NE. Nos depósitos, foram encontradas idades entre 8185 e 2165 anos cal A.P. e delimitadas quatro associações de fácies: desembocadura lagunar, delta de maré enchente, planície de maré e eólica. No setor Rio do Meio, a retrobarreira atua como planície interlagunar, separando a laguna Camacho (a SW) da laguna Santa Marta (para NE). Esta planície posiciona-se à retaguarda dos costões rochosos Ponta do Ilhote Pequeno e Cabo de Santa Marta, onde se originou a partir da formação de um tômbolo. Corresponde ao setor de maior influência continental pela frente deltaica do rio Tubarão, com três associações de fácies deposicionais: tômbolo, lagunar e planície de maré. As idades \'ANTPOT.14 C\' nas duas últimas associações variam entre 4650 e 1850 anos cal A.P.. Em Campos Verdes, a retrobarreira é formada por alinhamento de cordões litorâneos transversais à costa atual, separados entre si por truncamentos em padrão côncavoconvexo. Parte dos cordões superpõe-se por campos de paleodunas parabólicas atribuídas à geração eólica 3 (pós-máxima inundação). Neste setor, encontram-se três associações de fácies: pontal lagunar, cordões litorâneos e dunas eólicas. A análise integrada dos resultados permitiu diferenciar três fases evolutivas na retrobarreira. A Fase 1, entre 8000 e 5000 anos cal A.P. abrange o período de progressiva elevação e de mais alto nível do mar. A influência marinha na Fase 1 é evidenciada nos depósitos da retrobarreira com abundante concentração de conchas (inteiras e fragmentadas) de sistemas marinhos e lagunares/baía; a matéria orgânica preservada nos sedimentos apresentou valores de \'delta\'\'POT.13\'C entre -19 e -22%o , típicos de fitoplâncton marinho; a variação isotópica em conchas, com valores de \'delta\'\'POT.13\'C entre 1,22%o e 0,20%o e de \'delta\'\'POT.18\'O de - 0,5%o a - 1,8%o , indica o predomínio da dinâmica sedimentar marinha durante a fase 1. Interpretou-se que na Fase 1 a área de estudo foi ocupada por extenso sistema baía, com vales incisos afogados e ilhas emersas (representadas pelos atuais costões rochosos de Ponta do Ilhote Pequeno, Cabo de Santa Marta e Ponta da Galheta). Com a formação da barreira a baía isolou-se do mar raso, dando lugar ao corpo de água lagunar mixoalino. Na Fase 2, de 5000 a 3000 anos cal A.P., sob condições de NRM declinante, observou-se o desenvolvimento sedimentar diferenciado dos quatro setores retrobarreira, condicionado pela morfologia preexistente e pelo suprimento sedimentar. Os depósitos da Fase 3, de cerca de 3000 anos A.P. ao atual, caracterizam-se por: ausência de conchas, predomínio de fácies de areia fina com detritos vegetais, aumento ascendente dos valores de \'C IND.org\' e queda da razão \'delta\'\'POT.13\'C em sedimentos, alcançando valores típicos de plantas C3 e C4. Durante esta fase, a disponibilidade de sedimentos pela progradação da frente deltaica sobre a margem lagunar, associada à continuidade da queda de NRM, acelerou o assoreamento e a emersão das feições lagunares. Estas passaram a ser remodeladas pela circulação lagunar intermarés, o que determinou seu recobrimento pelas marismas e pântanos de maré. A Fase 3 pode ser considerada como de máxima estabilização das dunas eólicas, com formação de extensa planície de deflação e interdunas alagadas. Atesta-se assim a redução da influência de águas marinhas, possivelmente associada a alongamento, restrição ou mesmo fechamento da desembocadura lagunar, com aumento relativo do aporte de matéria orgânica continental. / The aims of this thesis is to identify the morphological features and understand the facies succession of the Holocene backbarrier in the Jaguaruna-Laguna region (Santa Catarina, Brazil). This backbarrier is formed by four geographic sectors, from SW to NE: Garopaba do Sul, Camacho, Rio do Meio and Campos Verdes. Regarding the geomorphological context, the sector of Garopaba do Sul differs from the others by the existence of a Pleistocene marine terrace, which is partly covered by paleodunes (generation 2) pre-maximum Holocene relative sea level (RSL), and by the presence of a residual lake of the lagoon system (Laranjal Lake). The depositional facies succession shows radiocarbon ages between 5560 and 2190 cal yr BP, being characterized by three facies associations: lagoonal, tidal flat and aeolian. The backbarrier of Camacho is sited beside the narrowest part of the barrier. Its main morphologic features are flood tidal paleodeltas associated with the migration of the Camacho inlet toward NE. Four facies associations were defined in this sector, with ages between 8185 and 2165 cal yr BP: inlet, flood-tidal delta, tidal plain and aeolian. At Rio do Meio, the backbarrier consists in an tidal flat separating the Camacho lagoon (SW) from the Santa Marta lagoon (NE).This plain is located rearward from Ponta do Ilhote Pequeno and Cabo de Santa Marta, where it was originated from the formation of a tombolo separating the two lagoons. It is also the sector with greater influence of Tubarão river deltaic front. Three facies associations were recognized: tombolo, lagoonal and tidal flat. The \'ANTPOT.14 C\' ages obtained in lagoonal deposits vary between 5570 and 1850 cal yr BP. In Campos Verdes, the backbarrier is formed by sets of beach ridges alignments, oriented transversal to the coastline and separated from each other by concave-convex truncations. Part of the ridges are superposed by several inactive parabolic dune-fields, attributed to the aeolian generation 3 (post maximum Holocene flooding).This sector is formed by three facies association: lagoon spit, beach ridges and aeolian dunes. The multi-proxy analysis of the set of results enabled the differentiation of three evolutionary phases in the backbarrier. The Phase 1, from 8000 to 5000 cal yr BP, comprises the period of progressive elevation and highest relative sea-level. The marine influence in this Phase 1 is recorded by abundant shells and shell fragments from invertebrates that live in marine and lagoonal/bay environments; the organic matter preserved in the sediments show \'delta\'\'POT.13\'C inside the interval between -19 and -22%o which is typical of marine phytoplanktons; in the shells, the vertical variation of \'delta\'\'POT.13\'C (from 1.22%o to 0.20%o) and \'delta\'\'POT.18\'O (from -0.5%o to -1.8%o) indicates the influence of marine in this Fase 1. This led to the conclusion that in this Phase 1, the survey area should be occupied by an extensive bay system, with drowned incised valleys and isolated islands (represented by the current Ponta do Ilhote Pequeno, Cabo de Santa Marta and Ponta da Galheta). With fhe formation of the barrier the bay was separated from the shallow open sea, giving place to the lagoonal mixohaline water body. During Phase 2, from 5000 to 3000 years cal BP, under declining sea-level conditions, the four backbarrier sectors experienced different sedimentary evolutions, conditioned by the pre-existing morphology and sedimentary supply of each one. The deposits of the Phase 3, from around 3000 years BP to the present, are characterized by: absence of shells, predominance of fine sand facies with plant debris, increasingly higher amounts of \'C IND.org\' and lower \'delta\'\'POT.13\'C ratio in sediments, which begin to record values typical of C3 and C4 plants. This phase is interpreted as resulting from the progradation of the delta front on the lagoon margin, combined with the continued reduced sea level, accelerated filling process and emersion of lagoonal features. These features were remodeled by the lagoonal circulation, determining the recovering by tidal marshes. Phase 3 can also be considered as the maximum stabilization of aeolian dunes, with the formation of an extensive deflation plain and wet interdunes. This reducing of marine influence is potentially associated with the stretching, limitation or even closing of the lagoon mouth, with relative increase in the accumulation of continental organic matter.

Le cadmium (Cd) est un élément toxique. Les activités humaines ont contaminé un large éventail de sols agricoles. L'exposition de l'homme au Cd se fait majoritairement par voie alimentaire, notamment à travers les aliments de base tels que les céréales. Le blé dur accumule naturellement plus de Cd dans ses grains que les autres céréales. Une fraction significative de la production française de blé dur dépasse la limite réglementaire européenne fixée pour le Cd. Il est donc nécessaire de réduire l'accumulation de Cd dans les grains de blé dur. Cette thèse portant sur l'écophysiologie de l'allocation du Cd aux grains chez le blé dur a pour ambition d'aider au développement de stratégies agronomiques visant à réduire le niveau de contamination en Cd du blé dur et de ses dérivés.Dans un premier temps, nous avons étudié la relation entre la structure de la biomasse aérienne et l'allocation de Cd aux grains. Nous avons fait l'hypothèse que la répartition de la biomasse aérienne entre pailles et grains était un facteur déterminant de l'allocation du Cd aux grains. Huit cultivars Français de blé dur - de hauteur de paille contrastée - ont été cultivés en présence de Cd. Comme prévu, le principal facteur expliquant la différence d'accumulation de Cd dans le grain était la structure de la biomasse aérienne. Les cultivars allouant une plus grande proportion de leur biomasse aérienne aux pailles - autrement dit les cultivars à longue tige - avaient tendance à accumuler moins de Cd dans leurs grains, car les tiges et les feuilles sont des puits de Cd en concurrence avec les grains lors de leur remplissage.Les minéraux importés dans les grains proviennent soit de leur absorption directe par la racine après l'anthèse, soit de leur remobilisation depuis des réserves constituées avant l'anthèse. La deuxième partie de ce travail a été consacrée à déterminer l'importance quantitative de ces deux « sources » pour le Cd chez le blé dur, et de préciser comment leur contribution relative varie entre cultivars et avec le niveau d'azote (N). Le traçage isotopique a été utilisé pour suivre le flux de Cd absorbé après l'anthèse. L'impact du niveau d'azote a été testé en privant la moitié des plantes de N après l'anthèse, sur deux cultivars montrant une capacité contrastée à accumuler le Cd dans leurs grains. La contribution de la remobilisation a été estimé à 50%, ce qui signifie que la moitié du Cd accumulé dans les grains provenait du Cd prélevé après l'anthèse. Le Cd a été remobilisé à partir des tiges, peut-être des racines, mais pas à partir des feuilles. La contribution de la remobilisation n'a pas varié entre les deux cultivars, de sorte qu'aucune relation entre la « source » de Cd et son niveau d'accumulation dans le grain n'a été mise en évidence. La privation d'azote en phase de remplissage a stimulé la remobilisation de N sans affecter celle de Cd, ce qui suggère que la remobilisation de Cd est un processus indépendant de la sénescence.En troisième lieu, nous avons examiné comment les caractéristiques d'allocation de Cd aux grains étaient modulées par le niveau d'exposition au Cd. [...]Enfin, nous nous sommes intéressés à la localisation de Cd dans le grain. [...] Ce travail a fourni la première carte de localisation de Cd dans un grain de blé dur. La distribution de Cd s'est caractérisée par une forte accumulation de Cd dans le sillon et par une dissémination dans l'endosperme amylacé plus prononcée que celle de Fe et Zn. / Cadmium (Cd) is a toxic element. Human activities have contaminated a wide range of agricultural soils. Most of Cd entering human bodies is through the dietary intake, and especially through staple food like cereals. Durum wheat naturally accumulates more Cd in its grains than other cereals. A significant fraction of the French durum wheat production has been found to exceed the European regulatory limit set for Cd. There is thus a need to reduce the accumulation of Cd in durum wheat grains. This thesis is dedicated to a better understanding of the ecophysiology of Cd allocation to the grains in durum wheat, with the ambition of helping to find agronomic strategies to reduce the Cd contamination level of durum wheat products.In first, we investigated the relationship between the aboveground partitioning of Cd and the shoot allometry. We hypothesized that the partitioning of shoot biomass between grains and straws is a driver of the allocation of Cd to the grains. Eight French durum wheat cultivars differing in their stem height were grown in presence of Cd. As expected, the main factor explaining the difference in their grain Cd was the shoot biomass partitioning. Cultivars allocating a higher proportion of their aerial biomass to the straws, i.e. long-stem cultivars, tended to accumulate less Cd in their grains because stems and leaves are sinks for Cd in competition with developing grains.Minerals imported into cereal grains originate from either direct post-anthesis root uptake or from the remobilization of pre-anthesis stores. The second part of this work was dedicated to determine the quantitative importance of these two pathways for Cd in durum wheat, and how their relative contribution vary between cultivars and with the level of nitrogen (N) supply. Stable isotopic labelling was used to trace the flux of Cd taken up post-anthesis. The impact of N supply was tested by depriving half of the plants of N after anthesis, in two cultivars showing a contrasted ability to accumulate Cd in their grains. The contribution of Cd remobilization was around 50%, which means that half of Cd in grains originated from Cd taken up pre-anthesis. Cd was remobilized from stems, possibly from roots, but not from leaves. The contribution of remobilization did not vary between the two cultivars so that no relationship between the pathway and the level of accumulation of Cd in grain was evidenced. Post-anthesis N deprivation triggered the remobilization of N without affecting that of Cd, which suggests that Cd remobilization is a senescent-independent process.In third, we investigated how the characteristics of Cd allocation to the grains was affected by the level of Cd exposure. [...]In last, we focused on how Cd was distributed within durum wheat grains. [...] This work provided the first map of Cd localization in durum wheat grains. Cd distribution was characterized by a strong accumulation of Cd in the crease and by a non-negligible dissemination in the starchy endosperm, as compared to Fe and Zn.

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The diet of the Stone Age cultures is a strong indicator to the social group, thus farmers and hunters can be distinguished through their diet. There is well-preserved and well excavated Polish skeletal material available for such a study but the material has not previously been subject to stable isotopes analyses and therefore the questions of diets has not been answered. This study aims to contribute to the understanding of the cultures in the Kichary Nowe 2 area in the Lesser Poland district in southern Poland. Through analysis of the stable isotopes of Carbon, Nitrogen and Sulphur in the collagen of teeth and skeletal bones from the humans in the Kichary Nowe 2 grave-field and from bones from the fauna, coeval and from the same area, the study will establish whether there were any sharp changes of diets. The material from the grave-field comes from cultures with an established agricultural economy, where their cultural belonging has been anticipated from the burial context. The results from my study of stable isotopes from the bone material will be grouped by various parameters, culture, attribution to sex and age. The groups will then be compared to each other to investigate patterns within and between the groups.