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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Meat on the hoof: A zooarchaeological and isotopic investigation of herd management at Khirbet Summeily in the Iron Age

Larson, Kara Marie 01 May 2020 (has links)
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.
2

The Ecology of Herbivorous Fishes in the Red Sea

Tietbohl, Matthew 11 1900 (has links)
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.
3

Fonctionnement trophique des récifs artificiels de la baie du Prado (Marseille, France) : Origine et devenir de la matière organique.

Cresson, Pierre 24 May 2013 (has links)
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.

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