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Thesis (Ph. D.)--Lehigh University, 2006. / Includes vita. Includes bibliographical references (leaves 187-192).

Cellulose-inferred lake water oxygen-isotope records were obtained from five throughflow lakes situated along a north-south transect across Fennoscandia to help develop a better picture of Holocene changes in atmospheric circulation in the region. This research addresses prior evidence for the existence of non-temperature-dependent shifts in d18O of precipitation in the early Holocene attributed to changes in atmospheric circulation. The validity of this hypothesis is tested through the development of oxygen-isotope records from lake sediments and their interpretation in the context of independent reconstructions of temperature and precipitation from pollen and chironomid head-capsules collected from the same or nearby sites, and well-documented changes in vegetation composition. Records of carbon and nitrogen elemental content and isotopic composition and magnetic susceptibility are included in this multi-proxy investigation. Extensive modern isotope hydrology datasets spanning several years at four of the five sites also help to inform interpretations of the cellulose d18O records. Key results from this research are: 1) Elevated d18O in relation to prevailing temperature occurred during the early Holocene (c. 10,000-6000 cal. BP) for sites in northern Fennoscandia (Lake Tibetanus, Lake Spåime), in harmony with previous interpretations suggesting that strong zonal atmospheric circulation led to deepening of the precipitation and isotope shadows in the lee of the Scandes Mountains. 2) Evidence from a southern site (Arbovatten) reveals a previously unrecognized negative offset in the d18O-temperature relation during the early Holocene, apparently transferred directly from the North Atlantic without the orographic effects associated with a topographic barrier. 3) The modern d18O-temperature relation appears to have been established throughout Fennoscandia by c. 6000-4000 cal. BP, probably due to generally weaker circumpolar atmospheric circulation in response to lower summer insolation. 4) Comparison of two sites (Lake Spåime, Svartkälstjärn) in a west-east transect across central Fennoscandia reveals higher-frequency variability in atmospheric circulation at submillennial scales throughout the Holocene, which appears to be analogous to contemporary variability in the North Atlantic Oscillation (NAO) at seasonal-to-decadal time-scales. Evidence of such NAO-like variability also exists at two northern sites (Lake Keitjoru, Oikojärvi) during the Holocene, likely reflecting variations in summer and winter atmospheric circulation. 5) Complex lake-specific changes in productivity occurred in response to Holocene climate change, as revealed by carbon and nitrogen elemental and isotopic data in lake sediments. A major shift in atmospheric circulation pattern occurring at c. 4000 cal. BP probably led to a reduction in soil-derived 13C-depleted nutrients in five lakes (Lake Keitjoru, Oikojärvi, Lake Spåime, Svartkälstjärn, Arbovatten) associated with changes in terrestrial vegetation. Changes in sediment nitrogen isotope composition also occurred in these lakes at c. 4000 cal. BP, possibly reflecting changing nutrient supply dynamics because of enhanced nitrogen losses during spring snowmelt.

Cellulose-inferred lake water oxygen-isotope records were obtained from five throughflow lakes situated along a north-south transect across Fennoscandia to help develop a better picture of Holocene changes in atmospheric circulation in the region. This research addresses prior evidence for the existence of non-temperature-dependent shifts in d18O of precipitation in the early Holocene attributed to changes in atmospheric circulation. The validity of this hypothesis is tested through the development of oxygen-isotope records from lake sediments and their interpretation in the context of independent reconstructions of temperature and precipitation from pollen and chironomid head-capsules collected from the same or nearby sites, and well-documented changes in vegetation composition. Records of carbon and nitrogen elemental content and isotopic composition and magnetic susceptibility are included in this multi-proxy investigation. Extensive modern isotope hydrology datasets spanning several years at four of the five sites also help to inform interpretations of the cellulose d18O records. Key results from this research are: 1) Elevated d18O in relation to prevailing temperature occurred during the early Holocene (c. 10,000-6000 cal. BP) for sites in northern Fennoscandia (Lake Tibetanus, Lake Spåime), in harmony with previous interpretations suggesting that strong zonal atmospheric circulation led to deepening of the precipitation and isotope shadows in the lee of the Scandes Mountains. 2) Evidence from a southern site (Arbovatten) reveals a previously unrecognized negative offset in the d18O-temperature relation during the early Holocene, apparently transferred directly from the North Atlantic without the orographic effects associated with a topographic barrier. 3) The modern d18O-temperature relation appears to have been established throughout Fennoscandia by c. 6000-4000 cal. BP, probably due to generally weaker circumpolar atmospheric circulation in response to lower summer insolation. 4) Comparison of two sites (Lake Spåime, Svartkälstjärn) in a west-east transect across central Fennoscandia reveals higher-frequency variability in atmospheric circulation at submillennial scales throughout the Holocene, which appears to be analogous to contemporary variability in the North Atlantic Oscillation (NAO) at seasonal-to-decadal time-scales. Evidence of such NAO-like variability also exists at two northern sites (Lake Keitjoru, Oikojärvi) during the Holocene, likely reflecting variations in summer and winter atmospheric circulation. 5) Complex lake-specific changes in productivity occurred in response to Holocene climate change, as revealed by carbon and nitrogen elemental and isotopic data in lake sediments. A major shift in atmospheric circulation pattern occurring at c. 4000 cal. BP probably led to a reduction in soil-derived 13C-depleted nutrients in five lakes (Lake Keitjoru, Oikojärvi, Lake Spåime, Svartkälstjärn, Arbovatten) associated with changes in terrestrial vegetation. Changes in sediment nitrogen isotope composition also occurred in these lakes at c. 4000 cal. BP, possibly reflecting changing nutrient supply dynamics because of enhanced nitrogen losses during spring snowmelt.

<p>Stone Age research on Northern Europe frequently makes gross generalizations about the Mesolithic and Neolithic, although we still lack much basic knowledge on how the people lived. The transition from the Mesolithic to the Neolithic in Europe has been described as a radical shift from an economy dominated by marine resources to one solely dependent on farming. Both the occurrence and the geographical extent of such a drastic shift can be questioned, however. It is therefore important to start out at a more detailed level of evidence in order to present the overall picture, and to account for the variability even in such regional or chronological overviews. Fifteen Stone Age sites were included in this study, ranging chronologically from the Early Mesolithic to the Middle or Late Neolithic, c. 8300–2500 BC, and stretching geographically from the westernmost coast of Sweden to the easternmost part of Latvia within the confines of latitudes 55–59° N. The most prominent sites in terms of the number of human and faunal samples analysed are Zvejnieki, Västerbjers and Skateholm I–II. Human and faunal skeletal remains were subjected to stable carbon and nitrogen isotope analysis to study diet and ecology at the sites. Stable isotope analyses of human remains provide quantitative information on the relative importance of various food sources, an important addition to the qualitative data supplied by certain artefacts and structures or by faunal or botanical remains. A vast number of new radiocarbon dates were also obtained.</p><p>In conclusion, a rich diversity in Stone Age dietary practice in the Baltic Region was demonstrated. Evidence ranging from the Early Mesolithic to the Late Neolithic show that neither chronology nor location alone can account for this variety, but that there are inevitably cultural factors as well. Food habits are culturally governed, and therefore we cannot automatically assume that people at similar sites will have the same diet. </p><p>Stable isotope studies are very important here, since they tell us what people actually consumed, not only what was available, or what one single meal contained. We should not be deceived in inferring diet from ritually deposited remains, since things that were mentally important were not always important in daily life. Thus, although a ritual and symbolic norm may emphasize certain food categories, these may in fact contribute very little to the diet. By the progress of analysis of intra-individual variation, new data on life history changes have been produced, revealing mobility patterns, breastfeeding behaviour and certain dietary transitions. The inclusion of faunal data has proved invaluable for understanding the stable isotope ecology of a site, and thereby improve the precision of the interpretations of human stable isotope data. The special case of dogs, though, demonstrates that these animals are not useful for inferring human diet, since, due to the number of roles they possess in human society, dogs could deviate significantly from humans in their diet, and in several cases have been proved to do so. </p><p>When evaluating radiocarbon data derived from human and animal remains from the Pitted-Ware site of Västerbjers on Gotland, the importance of establishing the stable isotope ecology of the site before making deductions on reservoir effects was further demonstrated. </p><p>The main aim of this thesis has been to demonstrate the variation and diversity in human practices, challenging the view of a “monolithic” Stone Age. By looking at individuals and not only at populations, the whole range of human behaviour has been accounted for, also revealing discrepancies between norm and practice, which are frequently visible both in the archaeological record and in present-day human behaviour. </p>

Stone Age research on Northern Europe frequently makes gross generalizations about the Mesolithic and Neolithic, although we still lack much basic knowledge on how the people lived. The transition from the Mesolithic to the Neolithic in Europe has been described as a radical shift from an economy dominated by marine resources to one solely dependent on farming. Both the occurrence and the geographical extent of such a drastic shift can be questioned, however. It is therefore important to start out at a more detailed level of evidence in order to present the overall picture, and to account for the variability even in such regional or chronological overviews. Fifteen Stone Age sites were included in this study, ranging chronologically from the Early Mesolithic to the Middle or Late Neolithic, c. 8300–2500 BC, and stretching geographically from the westernmost coast of Sweden to the easternmost part of Latvia within the confines of latitudes 55–59° N. The most prominent sites in terms of the number of human and faunal samples analysed are Zvejnieki, Västerbjers and Skateholm I–II. Human and faunal skeletal remains were subjected to stable carbon and nitrogen isotope analysis to study diet and ecology at the sites. Stable isotope analyses of human remains provide quantitative information on the relative importance of various food sources, an important addition to the qualitative data supplied by certain artefacts and structures or by faunal or botanical remains. A vast number of new radiocarbon dates were also obtained. In conclusion, a rich diversity in Stone Age dietary practice in the Baltic Region was demonstrated. Evidence ranging from the Early Mesolithic to the Late Neolithic show that neither chronology nor location alone can account for this variety, but that there are inevitably cultural factors as well. Food habits are culturally governed, and therefore we cannot automatically assume that people at similar sites will have the same diet. Stable isotope studies are very important here, since they tell us what people actually consumed, not only what was available, or what one single meal contained. We should not be deceived in inferring diet from ritually deposited remains, since things that were mentally important were not always important in daily life. Thus, although a ritual and symbolic norm may emphasize certain food categories, these may in fact contribute very little to the diet. By the progress of analysis of intra-individual variation, new data on life history changes have been produced, revealing mobility patterns, breastfeeding behaviour and certain dietary transitions. The inclusion of faunal data has proved invaluable for understanding the stable isotope ecology of a site, and thereby improve the precision of the interpretations of human stable isotope data. The special case of dogs, though, demonstrates that these animals are not useful for inferring human diet, since, due to the number of roles they possess in human society, dogs could deviate significantly from humans in their diet, and in several cases have been proved to do so. When evaluating radiocarbon data derived from human and animal remains from the Pitted-Ware site of Västerbjers on Gotland, the importance of establishing the stable isotope ecology of the site before making deductions on reservoir effects was further demonstrated. The main aim of this thesis has been to demonstrate the variation and diversity in human practices, challenging the view of a “monolithic” Stone Age. By looking at individuals and not only at populations, the whole range of human behaviour has been accounted for, also revealing discrepancies between norm and practice, which are frequently visible both in the archaeological record and in present-day human behaviour.

This study compared traditional community analysis with stable-isotope trophic analysis to define process-based trophic elements of community structure in the eastern Gulf of Mexico, and developed a predictive capability regarding changes to fish community structure that would be expected from increasing eutrophication. Specifically, it used an existing trawl survey program (SEAMAP) to compare invertebrate herbivore (sponge and sea urchin) isotopes with groundfish isotopes, and then compared the resulting spatial patterns with spatial variation in community structure, as identified by cluster analysis. The comparison was applied to seven NMFS survey zones that extended offshore from the Caloosahatchee River, FL northwest to Mobile Bay, AL. Isotopic patterns were consistent with the presence of an oligotrophic-eutrophic spatial gradient in this region. δ15N values increased in the northwestward direction in herbivores and in each of the 17 fish species examined. In the southern NMFS survey zones, δ13C was elevated in shallow depths for individual fish species, but not in herbivores, indicating a higher proportion of benthically derived biomass contributed to the biomass of fish in the shallow parts of the southern NMFS zones. Fish community analysis using SIMPROF created a similar pattern, with distinct nearshore and offshore communities and also a northwesterly community transition. Among the 17 fish species, five appeared to have obligate dependence on either benthic or planktonic basal resources, while twelve species appeared to be have facultative relationships. Impairment of current water-quality (nutrients, turbidity, light transmission, chlorophyll a) is expected to lead to reductions in the abundance of both obligate and facultative benthic-dependent fishes.

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The bromeliads are conspicuous elements of the landscape and vegetation of Brazil, in the state of Sergipe occurs in the Atlantic forest ecosystems in the ecotone and caatinga. Bromeliads have an semiarid environment in adaptive capacity to occupy various habitats both on the ground, rocks and trees is partly attributed to its CAM photosynthetic response type obligatory and/or facultative. Isotopic studies to determine the leaf carbon isotope values show that these range from -10 to -28 of PDB standard. This study analyzed the isotopic composition of carbon and nitrogen organic matter and leaf in the crown of Aechmea aquilega at three habitats: Caatinga (white forest sclerophilous), Atlantic forest (Pirambu) and a transition area between Atlantic Forest and Caatinga, an exception area of white sand-quartizose. In each habitat were collected 4 bromeliads that live in isolated bush and four plants in the ground substrates with the objective of evaluating the hypothesis of facilitation of bromeliad-tank as accumulator of organic matter. The leaves and organic matter of the crown leaves were dried in a ventilated oven, crushed, sieved and made isotopic analysis of carbon-13, nitrogen-15, and total C:N on CENA-USP laboratories. The results of analysis of content C: N and isotope ratios showed significant variations of carbon and nitrogen in the crown of leaves, as well as the total abundance in both leaf biomass and particulate organic matter. Plants of Caatinga and Atlantic Forest obligatory assimilate carbon, while the ecotone of the bromeliads, the National Park of Serra de Itabaiana responded as much as in CAM binding to isolated bushes just as the composition of bromeliads is probably of autoctone origin-open grassy areas. The isotope ratio of the 15N is 22 times more enriched in the bromeliad leaf biomass of scrub plants in relation to the white sands and 2.6 higher than in the Atlantic forest habitat, while the particulate organic matter was enriched in all habitats, but the source this organic matter require explanation, however, the study supported the hypothesis on the functional role of facilitation in the three bromeliad habitats. According to the study, we observed that the adaptive success of higher plants associated with scrub bushes when the same was not observed in other habitats. In white sands bromeliads-tank, the substrate is sandy-quartzes hot, highly permeable, facilitating evaporation and drought in the summer suggesting that there is a condition of great stress, which these tank bromeliads are well adapted to soil and not on trees. / Estudos isotópicos para determinar os valores dos isótopos do carbono foliar mostram que estes variam -10 a -28 do padrão PDB. Este estudo analisou a composição isotópica do Carbono e Nitrogênio foliar e a matéria orgânica acumulada na coroa foliar de Aechmea aquilega de três habitats: Caatinga (Poço Verde), Mata Atlântica (Pirambu) e em um área de transição Mata Atlântica Caatinga (Areia Branca). Em cada habitat foi coletado quatro bromélias que vivem em moitas e quatro plantas isoladas em substratos do chão com o objetivo de avaliar a hipótese de facilitação da bromélia-tanque como acumuladora de matéria orgânica. As folhas e a matéria orgânica da coroa foliar foram secas em estufa ventilada, trituradas, peneiradas e as análises isotópicas do carbono, nitrogênio, teor de carbono e nitrogênio total foram realizadas no CENA-USP. Os resultados das analises de teor C:N e razões isotópicas mostraram variações significativas do carbono e nitrogênio na coroa foliar, assim como na abundância total tanto na biomassa foliar como na matéria orgânica particulada. As plantas da Caatinga e Mata Atlântica assimilam carbono facultativamente, enquanto as bromélias do ecótono, Parque Nacional da Serra de Itabaiana responderam como CAM obrigatórias tanto quando em moitas como isoladas, assim como estas bromélias tem composição de origem autóctone provavelmente de áreas abertas-graminosa. A razão isotópica do N15 é 22 vezes mais enriquecido na biomassa foliar das bromélias da Caatinga em relação às plantas das Areias Branca e 2,6 maiores que em habitat de Mata Atlântica, enquanto a matéria orgânica particulada em todos habitats foi enriquecida, porém a origem desta matéria orgânica necessita de explicações, todavia, o estudo apoiou a hipótese de facilitação no papel funcional da bromélia nos três habitats. De acordo com o estudo, foi observado que o sucesso adaptativo maior das plantas da Caatinga quando associada a moitas o mesmo não foi verificado nos outros habitats. Nas Areias Brancas, o substrato arenoso-quartizoso é quente, altamente permeável, favorecendo a evaporação e déficit hídrico no verão o que sugere que haja uma condição de grande estresse, a qual essas bromélias-tanque estão bem adaptadas no solo e não nas árvores.

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