Khirbet Summeily is an early Iron Age II site located northwest of Tell el-Hesi in Southern Israel. Excavations sponsored by the Cobb Institute of Archaeology have revealed a large structure with a potential ritual space dated to the Iron Age IIA (ca. 1000-980/850 B.C.E.). Recent interpretations suggest the site was integrated into a regional economic and political system and functioned as a potential administrative outpost based on the material culture and architecture recovered from the Iron Age IIA layers. This thesis presents the carbon, oxygen, and strontium isotopic analyses of intra-tooth samples from ovicaprine and cattle remains to test herd management strategies in connection to administrative and cultic provisioning activities. The animal remains are used as proxies to identify political and economic ties through herd management patterns. These results will test the hypothesis that Khirbet Summeily was an administrative outpost integrated into a larger political and/or economic network.

Herbivorous fishes include a diverse assemblage of species that target primarily benthic autotrophs. This is perhaps one of the most well-studied groups of coral reef fishes, often reputed to be key components of coral reef communities, contributing to coral reef health in numerous ways. Through their feeding ecology and benthic interactions, they help mediate algae-coral interactions which can allow for improved coral survival and health. Despite the wealth of literature documenting the prominent roles of these fishes in coral reef ecosystems, studies from the Red Sea are surprisingly lacking. The Red Sea is a marginal reef environment, with a host of unique environmental and biological characteristics making it a unique environment where dynamics of herbivory may differ. This dissertation aims to fill key gaps in our knowledge of herbivorous fishes through the study of their distribution and trophic ecology. Herein, I describe habitat-specific partitioning of Red Sea herbivorous fish assemblages, discovering higher diversity and abundance found in reefs closer to shower, dissimilar to findings from other regions. Cross-shelf variation in assemblage structure seems to be quite robust through time, indicating short-term stability in herbivore assemblages. Through the use of stomach contents and stable isotope analyses, I then investigate the trophic ecology of browsing herbivores across the same shelf-gradient. I found higher trophic redundancy on nearshore reefs through time, with increased variation in diet and high levels of complementarity on offshore reefs where macroalgae are scarce. Stable isotope analyses of both liver and muscle revealed the stability of this resource partitioning through time, demonstrating for the first-time temporal stability of resource partitioning within this group. This dissertation broadens our knowledge of herbivorous fishes, filling important gaps. It offers new insight into the role of habitat in structuring trophic ecology and how flexible the diets of browsing species can be. Together, this information creates a foundation where improved knowledge of herbivorous fish ecology could be incorporated into future management plans of ongoing giga projects within the Kingdom. Incorporating herbivores into these plans could allow for increased resiliency for Red Sea coral reefs in the face of future development and shifting climatology.

Establishing a chronology of variation in isotopic values can reveal frailty associated with biological and social age, as well as highlight individuals who vary from typical patterns. Although general dietary characteristics and infant feeding practices were previously unknown for subadults excavated from the cemetery at Alytus, Lithuania (14th-18th centuries), previous research concludes that Alytus' subadults experienced high rates of physiological, metabolic, non-specific stress, in addition to specific diseases like tuberculosis. To investigate nuanced relationships between diet and mortality, nitrogen and carbon stable isotopes from the femoral and humeral midshaft diaphyses of 70 subadults (32 weeks gestation to16 years) were analyzed. Dietary reconstruction reveals that on average, exclusive breastfeeding continued until around 2 years of age when enriched ?13C (-19.6‰) and ?15N values (12.7‰) begin to deplete suggesting introduction of C3 grain gruels and potential weaning-associated infirmity. Nitrogen values remained slightly elevated in children (3-5 years, 11.2‰) until the beginning of juvenility (5-8 years, 10.3‰) when ?15N more closely mirrored adult values (16 years, 10.2‰), consistent with predominant consumption of terrestrial animal protein, possibly with riverine influence. The difference between femoral to humeral ? F-H 13C (-0.05 ±0.25‰, 1?) and ? F-H 15N (- 0.01±0.45‰, 1?) was not significant, though humeral values were on average more enriched. Enrichments in humeral nitrogen and carbon coincided with estimated weaning age. Cohorts experiencing childhood and adolescent growth spurts experienced higher femoral ?13C and ?15N values. Examining dietary experience and physiological changes contributes a holistic understanding of subadult morbidity and mortality experiences in Medieval Lithuania.

L'installation de récifs artificiels est une solution classiquement proposée pour soutenir la petite pêche artisanale. C'est dans ce but qu'a été déployé dans la baie de Marseille le plus grand ensemble de récifs artificiels de Méditerranée. Ce système offre une opportunité de comprendre le fonctionnement trophique de ces structures par (1) la caractérisation des sources de matière organique (MO) (2) la détermination de leur utilisation par les consommateurs et (3) leur devenir au sein des réseaux trophiques. Ces questions ont été appréhendées à l'aide des isotopes stables du C et du N, de la caractérisation biochimique des sources de MO et de l'analyse des contenus stomacaux des poissons.Les sources de MO présentent des différences isotopiques et biochimiques, reflet de leurs fonctionnements différents. La MO particulaire en suspension est un pool variable influencé par les apports allochtones et soumis aux forçages climatiques. Elle est la source principale de MO sur les récifs artificiels. La production primaire benthique est très hétérogène et de qualité nutritionnelle faible. Elle contribue aux réseaux trophiques des récifs par le biais des détritus qu'elle produit. Enfin, la MOS est un pool détritique de faible qualité nutritionnelle. Les récifs artificiels ne modifient pas la structure et le fonctionnement des communautés naturelles de poissons et leur offrent des ressources alimentaires variées et importantes. L'ensemble des résultats acquis, via les isotopes stables et les contenus stomacaux, montrent que les récifs artificiels sont des producteurs de biomasse à partir des productions primaires locales. / Artificial reefs are a classical tool used to sustain small scale fisheries. In Marseille's Bay, the largest Mediterranean artificial reef system was deployed for this purpose. This system is a valuable opportunity to better understand the trophic functioning of artificial reefs, by (1) characterizing the organic matter (OM) sources, (2) determining how they are used by low trophic level consumers and (3) following their fate in the trophic networks. These issues were assessed by three approaches:C and N stable isotope ratios, biochemical composition of OM sources and fish stomach content.OM sources display isotopic and biochemical differences reflecting their functioning. Suspended POM is variable, under the influence of allochtonous inputs and controlled by climatic forcing. POM represents the main OM source of the artificial reef food webs. The benthic primary production has heterogeneous C and N stable isotope ratios and exhibits mainly high insoluble carbohydrates contents. Benthic primary production is integrated into trophic networks mainly in the form of detritus. Eventually the sediment organic matter is a detrital pool, characterized by a low variability and a poor nutritional quality.Artificial reefs do modify the organization and the functioning of natural fish communities, and provide diversified and important food resources. Stable isotope and stomach content analyses confirm the consumption of artificial reef invertebrates by small carnivorous fishes, preyed themselves by piscivorous predators. All these results confirm that artificial reefs can efficiently increase fish biomass by local production based on phytoplanktonic and local benthic OM sources.

A mechanistic understanding of transport and degradation processes of modern agricultural pesticides, including chiral pesticides, is critical for predicting their fate in the environment. In agricultural landscapes, wetlands can intercept pesticide-contaminated runoff or groundwater and improve water quality through various retention and degradation processes, which remain unknown. In a downscaling approach, three different wetlands receiving agricultural runoff were used as 'natural laboratories' to investigate the fate of widely used pesticides. Overall, our results showed that dynamics of hydrological and redox conditions largely influenced pesticide sorption mechanisms and their distribution over time within wetland compartments, thereby controlling degradation processes. While large-scale studies provide integrative information on pesticide dissipation and distribution patterns with respect to wetland functioning, small-scale investigations using novel methods such as isotope and enantiomer analyses characterize underlying molecular processes governing pesticide degradation.

The field of noble gas mass spectrometry is a rapidly developing one. There is a sustained requirement for continuous development of instrumentation in order to allow researchers to answer critical questions facing their respective fields. Within planetary science, the question of whether our solar system is 'typical', has been a driving force behind many lines of research. This project sought to build upon the strong instrumental base of the Isotope Geochemistry and Cosmochemistry group of the University of Manchester, in order to develop the Resonance Ionisation Mass Spectrometer for Krypton Isotopes. From that basis, it then sought to develop techniques and protocols for the analysis of extra-terrestrial samples, particularly those of very low mass. The thesis is broken down into three studies. The first involved the development of the mechanisms used to fill the Xe-Ar four-wave mixing cell. This section covers the development, implementation, and characterisation of the newly installed mass flow controllers. The additional control over the mixing ratio granted allowed an eightfold increase to the sensitivity of the instrument. The reproducibility of the gas ratio is consistently shown throughout, and has ultimately reduced the tuning time of the instrument from a number of weeks to a day. The second section details the required procedures involved in data reduction, and the development of protocols and software for the RIMSKI instrument. A range of approaches are assessed, including a novel approach to cosmic ray exposure age calculations. The methods are discussed and implemented on extra-terrestrial samples, the Stannern eucrite and the Bereba eucrite. Finally, the analytical limits of the RIMSKI instrument are expanded via the measurement of the krypton systems of individual calcium-aluminium-rich inclusions. It is observed that Allende CAIs show a trapped component, Br-derived Kr, as well as an anomalous 'heavy Kr' component (one that is enriched in 86Kr). It is additionally noted that there is a lack of cosmogenic krypton to be found in all but one of the measured inclusions. The implications of these findings are discussed.

This thesis presents investigations on sediments from two African lakes which have been recording changes in their surrounding environmental and climate conditions since more than 200,000 years. Focus of this work is the time of the last Glacial and the Holocene (the last ~100,000 years before present [in the following 100 kyr BP]). One important precondition for this kind of research is a good understanding of the present ecosystems in and around the lakes and of the sediment formation under modern climate conditions. Both studies therefore include investigations on the modern environment (including organisms, soils, rocks, lake water and sediments). A 90 m long sediment sequence was investigated from Lake Tswaing (north-eastern South Africa) using geochemical analyses. These investigations document alternating periods of high detrital input and low (especially autochthonous) organic matter content and periods of low detrital input, carbonatic or evaporitic sedimentation and high autochthonous organic matter content. These alternations are interpreted as changes between relatively humid and arid conditions, respectively. Before c. 75 kyr BP, they seem to follow changes in local insolation whereas afterwards they appear to be acyclic and are probably caused by changes in ocean circulation and/or in the mean position of the Inter-Tropical Convergence Zone (ITCZ). Today, these factors have main influence on precipitation in this area where rainfall occurs almost exclusively during austral summer. All modern organisms were analysed for their biomarker and bulk organic and compound-specific stable carbon isotope composition. The same investigations on sediments from the modern lake floor document the mixed input of the investigated individual organisms and reveal additional influences by methanotrophic bacteria. A comparison of modern sediment characteristics with those of sediments covering the time 14 to 2 kyr BP shows changes in the productivity of the lake and the surrounding vegetation which are best explained by changes in hydrology. More humid conditions are indicated for times older than 10 kyr BP and younger than 7.5 kyr BP, whereas arid conditions prevailed in between. These observations agree with the results from sediment composition and indications from other climate archives nearby. The second lake study deals with Lake Challa, a small, deep crater lake on the foot of Mount Kilimanjaro. In this lake form mm-scale laminated sediments which were analyses with micro-XRF scanning for changes in the element composition. By comparing these results with investigations on thin sections, results from ongoing sediment trap studies, meteorological data, and investigations on the surrounding rocks and soils, I develop a model for seasonal variability in the limnology and sedimentation of Lake Challa. The lake appears to be stratified during the warm rain seasons (October – December and March – May) during which detrital material is delivered to the lake and carbonates precipitate. On the lake floor forms a dark lamina with high contents of Fe and Ti and high Ca/Al and low Mn/Fe ratios. Diatoms bloom during the cool and windy season (June – September) when mixing down to c. 60 m depth provides easily bio-available nutrients. Contemporaneously, Fe and Mn-oxides are precipitating which cause high Mn/Fe ratios in the light diatom-rich laminae of the sediments. Trends in the Mn/Fe ratio of the sediments are interpreted to reflect changes in the intensity or duration of seasonal mixing in Lake Challa. This interpretation is supported by parallel changes in the organic matter and biogenic silica content observed in the 22 m long profile recovered from Lake Challa. This covers the time of the last 25 kyr BP. It documents a transition around 16 kyr BP from relatively well-mixed conditions with high detrital input during glacial times to stronger stratified conditions which are probably related to increasing lake levels in Challa and generally more humid conditions in East Africa. Intensified mixing is recorded for the time of the Younger Dryas and the period between 11.4 and 10.7 kyr BP. For these periods, reduced intensity of the SW monsoon and intensified NE monsoon are reported from archives of the Indian-Asian Monsoon region, arguing for the latter as a probable source for wind mixing in Lake Challa. This connection is probably also responsible for contemporaneous events in the Mn/Fe ratios of the Lake Challa sediments and in other records of northern hemisphere monsoon intensity during the Holocene and underlines the close interaction of global low latitude atmospheric circulation. / In dieser Arbeit werden Ergebnisse von Untersuchungen an den Sedimenten zweier afrikanischer Seen vorgestellt, die ein Archiv für Klimaveränderungen über einen Zeitraum von mehr als 200.000 Jahren darstellen. Der Schwerpunkt liegt in dieser Arbeit auf dem letzten Glazial und dem Holozän (ca. 100.000 Jahre vor heute [nachfolgend als 100 kyr BP bezeichnet] bis heute). Grundlegende Voraussetzung für solche Studien ist ein gutes Verständnis der Ökosysteme in und um den See, sowie des gegenwärtigen Sedimentationsgeschehens. Deswegen beinhalten beide Seestudien Untersuchungen der heutigen Organismen, Böden, Gesteine, Wasserchemie und Sedimentablagerungen. Im Tswaing-See im nordöstlichen Südafrika wurden anhand eines 90 m langen Sedimentprofils Studien zur Sedimentzusammensetzung und Untersuchungen der Zusammensetzung und Qualität des organischen Materials durchgeführt. Sie zeigen einen Wechsel zwischen Phasen hohen detritischen Eintrags, während derer v.a. kaum autochthones organisches Material im See erhalten blieb, mit Phasen geringen Eintrags und dafür karbonatischer oder evaporitischer Sedimentation, die hohe Gehalte v.a. autochthonen organischen Materials aufweisen. Diese Phasen werden als relativ feuchte bzw. trockene Perioden interpretiert und folgen bis vor ca. 75 kyr BP Schwankungen der lokalen solaren Einstrahlung. Dieser Einfluss nimmt nach 75 kyr BP ab und azyklische feuchte Phasen werden beobachtet. Mögliche Ursachen sind Veränderungen in der ozeanischen Zirkulation und Verschiebungen in der Lage der Innertropischen Konvergenzzone (ITCZ); beides sind auch heute Haupteinflussfaktoren auf die Niederschläge in der Region. Die heute lebenden Organismen des Tswaing-Kraters wurden mittels Analysen der Biomarkerzusammensetzung und der Kohlenstoffisotopie charakterisiert und ihr Einfluss auf die heutigen Seeablagerungen untersucht. Dabei konnten zusätzlich Indikatoren für die Aktivität methanotropher Bakterien nachgewiesen werden. Der Vergleich heutiger Sedimente mit denen des Zeitraumes 14 bis 2 kyr BP zeigt deutliche Veränderungen sowohl in der Zusammensetzung, als auch in der Kohlenstoffisotopie der Biomarker, die mit Veränderungen in der Hydrologie erklärt werden können. Die gefundenen Hinweise auf feuchtere Bedingungen im Zeitraum älter als 10 kyr BP, für trockenere Verhältnissen zwischen 10 und 7.5 kyr BP und für die nachfolgende Wiederzunahme an Feuchtigkeit werden durch die sedimentologischen Ergebnisse unterstützt. Objekt der zweiten Seestudie ist der Challa-See am Fuß des Kilimanjaro. Hier werden heute im mm-Maßstab laminierte Sedimente gebildet, die mit Mikro-XRF-scanning auf Veränderungen in der Elementzusammensetzung untersucht wurden. Zusammen mit Untersuchungen der Mikrofazies und im Vergleich mit ersten Ergebnissen noch laufender Sedimentfallenstudien, mit meteorologischen Daten und Analysen des Umgebungsgesteins werden die saisonalen Veränderungen in der Temperaturverteilung, der Durchmischungstiefe, dem detritischen Eintrag und der Bioproduktivität des Sees in den Sedimenten nachvollziehbar. Der See ist in den feucht-warmen Perioden von Oktober bis Dezember und von März bis Mai stratifiziert. Während dieser Zeit erfolgt der Eintrag detritischen Materials und Kalziumkarbonat fällt aus; eine dunkle Lage mit hohen Gehalten an Fe und Ti und mit hohen Ca/Al- und niedrigen Mn/Fe-Verhältnissen bildet sich am Boden des Sees. Diatomeen blühen während der kühlen, windigen Periode von Juni bis September, wenn die Durchmischung bis auf etwa 60 m Tiefe Nährstoffe verfügbar macht. Die Ausfällung von Fe- und Mn-oxiden sorgt für hohe Mn/Fe-Verhältnisse; es bildet sich eine helle Lage auf dem Sediment. Trends im Mn/Fe-Verhältnis werden als Signal für Veränderungen in der Intensität oder Dauer der saisonalen Durchmischung interpretiert. Dies wird unterstützt durch parallele Trends im Gehalt an organischem Material und an biogenem Silizium, wie durch Analysen an einem 22 m langen Bohrkern gezeigt werden kann. Nach gut durchmischten und von erhöhtem Eintrag von außen geprägten Verhältnissen während des letzten Glazials erfolgt gegen 16 kyr BP ein Übergang zu stärker stratifizierten Bedingungen. Diese korrespondieren mit einem steigenden Seespiegel und verbreiteten Hinweisen auf feuchte Bedingungen im tropischen Ostafrika. Stärkere Durchmischung herrschte während der Jüngeren Dryas und von 11.4 bis 10.7 kyr BP. Diese Perioden entsprechen Zeiten verringerter Südwest- und vermutlich verstärkter Nordostmonsunintensität im Bereich des Indisch-Asiatischen Monsuns und spiegeln eine global beobachtete südliche Verschiebung der ITCZ wider. Nach einer kurzen stabilen, feuchten Phase im frühen Holozän nimmt die Durchmischung des Sees im Verlauf des Holozän wieder zu. Abrupte Ereignisse während des Holozän scheinen im Challa-See zeitgleich mit Veränderungen der Monsunintensität der Nordhemisphäre aufzutreten und bezeugen die starke klimatische Kopplung der niederen Breiten in globalem Maßstab.

La compréhension des mécanismes de transport et de dégradation des pesticides émergents est primordiale pour prédire leur devenir dans l’environnement. Les zones humides peuvent intercepter des eaux de ruissellement ou des souterraines contaminées par les pesticides et les traiter par le biais de processus de rétention et de dégradation, encore peu connus. Dans une approche multi-échelles, trois zones humides recevant des eaux polluées par les pesticides ont été utilisées comme des « laboratoires naturels » pour étudier le devenir de pesticides couramment utilisés. Cette thèse souligne l’influence des conditions hydrologiques et redox sur la distribution des pesticides au sein des différents compartiments des zones humides ainsi que sur leur potentiel de dégradation. Alors que les études à grande échelle fournissent des informations intégratives sur la dissipation et la rétention des pesticides en lien avec le développement de la végétation, les études à petite échelle utilisant des techniques innovantes telles que les analyses isotopiques et énantiomériques permettent l’exploration des processus moléculaires de dégradation des pesticides. / A mechanistic understanding of transport and degradation processes of modern agricultural pesticides, including chiral pesticides, is critical for predicting their fate in the environment. In agricultural landscapes, wetlands can intercept pesticide-contaminated runoff or groundwater and improve water quality through various retention and degradation processes, which remain unknown. In a downscaling approach, three different wetlands receiving agricultural runoff were used as ‘natural laboratories’ to investigate the fate of widely used pesticides. Overall, our results showed that dynamics of hydrological and redox conditions largely influenced pesticide sorption mechanisms and their distribution over time within wetland compartments, thereby controlling degradation processes. While large-scale studies provide integrative information on pesticide dissipation and distribution patterns with respect to wetland functioning, small-scale investigations using novel methods such as isotope and enantiomer analyses characterize underlying molecular processes governing pesticide degradation.

Time and circumstances for the disappearance of Neanderthals and its relationship with the advent of Modern Humans are not yet sufficiently resolved, especially in case of the Iberian Peninsula. Reconstructing palaeoenvironmental conditions during the last glacial period is crucial to clarifying whether climate deteriorations or competition and contacts with Modern Humans played the pivotal role in driving Neanderthals to extinction. A high-resolution loess record from the Upper Tagus Basin in central Spain demonstrates that the Neanderthal abandonment of inner Iberian territories 42 kyr ago coincided with the evolvement of hostile environmental conditions, while archaeological evidence testifies that this desertion took place regardless of modern humans’ activities. According to stratigraphic findings and stable isotope analyses, this period corresponded to the driest environmental conditions of the last glacial apart from an even drier period linked to Heinrich Stadial 3. Our results show that during Marine Isotope Stages (MIS) 4 and 2 climate deteriorations in interior Iberia temporally coincided with northern hemisphere cold periods (Heinrich stadials). Solely during the middle MIS 3, in a period surrounding 42 kyr ago, this relation seems not straightforward, which may demonstrate the complexity of terrestrial climate conditions during glacial periods.

Time and circumstances for the disappearance of Neanderthals and its relationship with the advent of Modern Humans are not yet sufficiently resolved, especially in case of the Iberian Peninsula. Reconstructing palaeoenvironmental conditions during the last glacial period is crucial to clarifying whether climate deteriorations or competition and contacts with Modern Humans played the pivotal role in driving Neanderthals to extinction. A high-resolution loess record from the Upper Tagus Basin in central Spain demonstrates that the Neanderthal abandonment of inner Iberian territories 42 kyr ago coincided with the evolvement of hostile environmental conditions, while archaeological evidence testifies that this desertion took place regardless of modern humans’ activities. According to stratigraphic findings and stable isotope analyses, this period corresponded to the driest environmental conditions of the last glacial apart from an even drier period linked to Heinrich Stadial 3. Our results show that during Marine Isotope Stages (MIS) 4 and 2 climate deteriorations in interior Iberia temporally coincided with northern hemisphere cold periods (Heinrich stadials). Solely during the middle MIS 3, in a period surrounding 42 kyr ago, this relation seems not straightforward, which may demonstrate the complexity of terrestrial climate conditions during glacial periods.