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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.
81

Archeozoologie neolitu Čech / Archaeozoology of the Neolithic of Bohemia

KOVAČIKOVÁ, Lenka January 2011 (has links)
An archaeozoological analysis of the assemblages of animal bones and teeth of Neolithic (Linear and Stroked Pottery cultures; approx. 5500-4200 BC)settlements in Bohemia, provide new elements on the way of life of early farmers. By means of study of animal bones and teeth we can specify the role of domestic and hunting animals in the Neolithic economy, define the herd management strategies for main domestic animals and focus on the environmental reconstruction and investigation of births distribution of domestic animals (for exemple of cattle in the case of this study) through the analysis of the carbon and oxygen isotopic compositions of fossil tooth enamel bioapatite. To achieve these objectives, we can use, except standard archaeozoological methods and stable isotope analysis, more specific procedures, e.g. determination of damaged bones of animals using the ELISA test.
82

Foraging ecology of the Campbell Albatross : individual specialisation and fishery interactions

Sztukowski, Lisa Ann January 2016 (has links)
Most albatrosses are critically endangered, endangered or vulnerable due to the deleterious impact of fisheries, pollution, introduced species, habitat alteration, and climate change. Foraging behaviour influences many aspects of seabird biology, and a detailed understanding of foraging ecology is required to better predict the impacts of significant changes to the marine environment. Campbell Albatross (Thalassarche impavida) is a threatened endemic, confined to a small number of locations on Campbell Island, New Zealand and was recently split from the closely related Black-browed Albatross (T. melanophrys). We currently lack much basic information on the foraging behaviour of this species, hindering our ability to understand how change may have occurred in the past and make predictions about it’s long-term future. First, I used GPS loggers and stable isotope analysis of blood to investigate how distribution and foraging effort (distance travelled and duration) varied with sex and breeding stage. I found that Campbell Albatrosses are sexually dimorphic and showed sex-specific foraging behaviour and habitat use – although this varied by stage of reproduction. Because males and females may be vulnerable to different threats, such as interactions with fisheries, I compared the spatial overlap and high resolution spatio-temporal overlaps between fisheries vessels and albatrosses within New Zealand’s Exclusive Economic Zone (EEZ). Albatrosses utilised 32% of the EEZ, however they overlapped with fisheries vessels in only 0.20% of the area. Previous research has demonstrated that the influence of fisheries vessels goes beyond the immediate location of the boat itself. Campbell Albatross have low levels of spatio-temporal overlap with fisheries – with males overlapping more than females. More generally, my results indicate that adding data on fine scale interactions will improve fisheries risk assessments, and provide information needed for the conservation and management of the Campbell Albatross. A key development in recent ecological research has been a greater appreciation that inter-individual variation in foraging behaviour can have profound population-level consequences. Accordingly I tested for individual differences in foraging behaviour in Campbell Albatrosses. The majority of individuals demonstrated both annual and inter-annual individual consistency in foraging locations, and the degree of specialisation was influenced by both sex and year. Consistent terminal latitude and longitude of foraging trips indicated high foraging area fidelity with a degree of flexibility in the fine-scale location. During brooding, females used the Campbell Plateau and showed more consistent behaviours than males, which tended to forage in the Southern Ocean. This adds to a growing body of evidence of individual foraging specialisation among seabirds in general and albatrosses in particular and reveals marked inter-individual differences in vulnerability to threats. In light of the evidence of individual foraging specialisations in the Campbell albatross, I also preformed a literature review of individual foraging specialisations across all seabirds. I found studies examining foraging specialisation for 35 species, with 28 (80%) providing evidence of consistent inter-individual differences (i.e. specialisation). Current studies suggest that specialisation is influenced by environmental variability and resource predictability, however, with limited data in tropical regions, more studies are needed to test these links. In summary, my thesis has provided new information on Campbell Albatross foraging ecology. Sex specific variations in behaviour and habitat use may influence conservation and management strategies. I have been able to contextualise the consistent individual differences in foraging distribution described for this species in light of global patterns of individual foraging specialisation in seabirds and highlight future areas of research.
83

Trophic Study of Oilfish, Escolar, Snake Mackerel, and Lancetfish in the Western North Atlantic Ocean and the Gulf of Mexico Using Combined Stomach Content and Stable Carbon and Nitrogen Isotope Analyses

Keller, Heidi R. 01 July 2011 (has links)
Large, mesopelagic teleosts have a potentially keystone position in the ecology of the pelagic water column, yet remain relatively unstudied when compared to large, commercially important fishes of the epipelagic zone. In this study, the ecological roles of four large, vertically migrating teleosts, oilfish, Ruvettus pretiosus, escolar, Lepidocybium flavobrunneum, snake mackerel, Gempylus serpens, longnose lancetfish, Alepisaurus ferox, and shortnose lancetfish, Alepisaurus brevirostris, were examined. The stomachs of 61 oilfish, 35 escolar, 33 snake mackerel, and 34 lancetfish were collected from nighttime, pelagic, longline fishing operations in the epipelagic zone of the western North Atlantic Ocean and Gulf of Mexico from 2007 to 2010. Stomach content analysis was used to determine predator-prey interactions. Stable carbon and nitrogen isotope analyses were performed on white dorsal muscle tissue of 38 oilfish, 23 escolar, 28 snake mackerel, and 19 lancetfish also sampled for stomach content analysis. Crustaceans were abundant prey of small oilfish, lancetfish, and to a lesser degree, snake mackerel, and they were absent from large escolar diets. Lancetfish and snake mackerel showed diverse diets that included crustaceans, polychaetes, gymnosomes, salps, cephalopods, and fishes. Large escolar stomachs contained only squid and fish. Stable isotope analyses placed small oilfish in the lowest trophic position of the group, followed by lancetfish and snake mackerel, and large escolar occupied the highest trophic position of the four species.
84

Study of the Seasonal Water Cycle over the Indian Subcontinent and the Southern Ocean using Stable Isotopes in Rainwater and Water Vapor

Rahul, P January 2016 (has links) (PDF)
Stable isotope ratios in rainwater and water vapor act as a tracers of the hydrological cycle. The data on stable isotopic composition in rainwater and water vapor are limited due to the lack of observational studies across the Indian subcontinent and over the ocean. These present day observations are important database to deduce the paleo-climatic condition from geological archives. In majority of the cases, isotopic records are translated into physical factors with the present background knowledge where relationships with physical variables are well established. In case of tropical region, the primary controlling factor identified behind the stable isotopic variations is the amount of rainfall. However recent observations contradict such relationships challenging the role of amount effect and identified source moisture effect on stable isotope ratios in rainwater at Indian stations. The thesis investigated the amount effect relationship of isotopes at seasonal time scales. The long period observation covering 4 years, where daily time interval rainwater samples collected were used for our study. We used two different station locations; Thiruvananthapuram and Bangalore, where monsoonal rainfall is received for Southwest and Northeast periods. The role of mesoscale and synoptic convection and rainout along the transport pathways were found responsible for the isotopic variance. The role of moisture source regions, rainout over the advection pathways, high rainfall producing systems such as depression and cyclones, and continental recycling of water on rainwater and water isotopes ratios were major findings of the thesis work which are detailed in the chapters. Upon knowing the atmospheric and oceanic condition at the moisture source region based on satellite data and reanalysis data set we modeled our observations using the governing equations of isotope fractionation and well accepted Rayliegh’s distillation model. The observations on rainwater and water vapor isotope ratios in oceanic region are extremely limited due to difficulties in conducting sampling. Water vapor and rainwater observations over the Southern Ocean during the expedition of 2013 and estimation of the moisture recycling across the latitudes over the oceanic regions is a novel work in this thesis.
85

Přenosové efekty v rámci ročního cyklu rákosníků velkých: celoareálová studie se zaměřením na rozdíly mezi pohlavími a populacemi / A range-wide assessment of carry-over effects within the full annual cycle of the Great Reed Warbler with a focus on sex and population differences

Brlík, Vojtěch January 2019 (has links)
Movements of long-distance migratory birds are frequently well timed and routed in order to maximise individual fitness. However, individual timing of events or environmental conditions experienced have a potential to carry over into subsequent annual cycle stages and may have delayed fitness consequences. Therefore, knowledge of these seasonal interactions is crucial to identify key periods and regions that limit survival beyond the breeding period and thus to fully understand population dynamics of migratory species. Despite current evidence for seasonal interactions, there is no detailed knowledge of the complex of relationships within the full annual cycle, differences between sexes and populations or impact of environmental conditions during moult in one species. To unveil this system of seasonal interactions within the annual cycle, we directly tracked 103 great reed warblers (Acrocephalus arundinaceus) using light-level geolocators from five breeding sites across the breeding range to obtain information on timing and positions of annual cycle events. We then combined this information with various remotely sensed habitat condition metrics and stable isotopic composition of feathers from the non-breeding grounds to identify and quantify carry-over effects within the full annual cycle. Our...
86

FORAGING ECOLOGY OF NESTING GREEN, OLIVE RIDLEY, AND LEATHERBACK TURTLES FROM NORTHWEST COSTA RICA

Alison Jenele Meeth (10716291) 28 April 2021 (has links)
<div>Understanding what sea turtles are feeding on and where they are feeding is key to understand their overall biology and will aid in understanding what type of management actions are necessary in order to conserve and protect these endangered species. Here I set out to (1) examine the population-level isotopic profiles of three sea turtle species in the Eastern Tropical Pacific; (2) determine differences in their foraging strategies; (3) attempt to gain insights about their pre-nesting origins; and (4) determine whether body size would influence the isotopic values of an individual turtle.</div><div>Stable isotope analysis (δ<sup>13</sup>C and δ<sup>15</sup>N values) was conducted on tissue samples from 52 sea turtles nesting on Playa Cabuyal, Costa Rica; 28 Pacific green (<i>Chelonia mydas</i>), 20 olive ridley (<i>Lepidochelys olivacea</i>), and 4 leatherback (<i>Dermochelys coriacea</i>). Nine satellite transmitters were also deployed on a separate population of post-nesting Pacific green turtles from Playa Cabuyal.</div><div>Based on isotopic profiles, green turtles in the Eastern Tropical Pacific were found to be feeding at a higher trophic level when compared to green turtles in other regions and this was supported by their increased δ<sup>15</sup>N values (16 ± 0.8 ‰). Rather than shifting to herbivory as adults, green turtles foraging in the eastern Pacific are potentially remaining omnivorous. Tracking data further confirmed that green turtles are coastal migrators and are probably inhabiting areas with high δ<sup>15</sup>N values within this region. Olive ridley turtles are exhibiting similar behavior to olive ridley turtles elsewhere due to minimal variance in their isotopic profiles (δ<sup>13</sup>C = -15.1 ± 0.7 ‰, δ<sup>15</sup>N =14.2 ± 0.8 ‰) and their known nomadic behavior. Although a small sample size, leatherback turtles showed a shift in their foraging habitats suggesting they are also feeding inshore in addition to their pelagic behavior due to their increased δ<sup>13</sup>C values (-15.5 ± 0.4 ‰). Further, as body size increased in olive ridley’s, the δ<sup>15</sup>N values significantly decreased suggesting that larger turtles prefer deeper pelagic waters with less enriched N isotope concentrations. However, in order to rule out possible external factors influencing this relationship, knowing where the turtle is originating from is crucial. This project provides data for developing isoscapes in the Eastern Tropical Pacific to aid in understanding the spatial distribution of sea turtles and their foraging grounds and the impact that foraging area may have on overall biology of these species. This information can be used to prioritize high use foraging habitats and determine the most effective management practices for protecting these species and the prey and habitat on which they rely.</div>
87

Changes In Neolithic Subsistence Patterns On Flores, Indonesia Inferred By Stable Carbon, Nitrogen, And Oxygen Isotope Analyses Of Sus From Liang Bua

Munizzi, Jordon 01 January 2013 (has links)
Despite an abundance of archaeological material recovered from sites in Island Southeast Asia, the timing and route by which cultigens first arrived in Wallacea remains unclear. Many of the staple crops now grown on these islands were domesticated in mainland Asia, and were deliberately introduced by humans at an unknown point during the Holocene, through several possible routes. In this study, the δ 13C, δ15N and δ18O values of subfossil bones and teeth attributed to Sus celebensis and Sus scrofa are analyzed. These materials, which span the last 5160 years at Liang Bua, Flores, Indonesia are used to determine if and when there was a shift towards agricultural intensification, and whether this intensification included the integration of domesticated C4 crops. The δ13C and δ15N values of the bone and dentin collagen samples indicate an abrupt shift towards enrichment in 13C and depletion in 15N at some time between 5160 and 2750 yBP. This hints at changes in human subsistence patterns that may have included the clearing of forests, and the integration of nonendemic C4 cultigens such as foxtail millet (Setaria italica) onto the island. No statistically significant variation in the δ 18O values of the enamel carbonate samples over time is observed, suggesting that once they appeared on Flores, semidomesticated pigs became an important part of the island ecosystem, and were bred and raised on Flores instead of being continuously imported from elsewhere.
88

An isotopic and historical study of diet and migration during the great Irish Potato famine (1845-1852). High-resolution carbon and nitrogen isotope profiling of teeth to investigate migration and short-term dietary change at the Union workhouse, Kilkenny and Lukin street, London.

Beaumont, Julia January 2013 (has links)
Historical evidence from contemporary documents established that Irish migrants to London during the Great Irish Famine (1845-1852) were likely to come from low socio-economic groups in south-west Ireland, and has characterised mid-19th-century health status and living conditions in both locations. Using samples from 119 individuals from the Catholic cemetery at Lukin Street, London (1843-1854) and 20 from the Union Workhouse Famine cemetery, Kilkenny, Ireland (1847-51), mean bone collagen isotope values were established for the well-documented Irish pre-Famine potato-based diet (¿15N 10.6¿, ¿13C -19.1¿), and the diet of contemporaneous Londoners (¿15N 12.6¿, ¿13C -19.1¿). The introduction of maize as a short-term Famine relief food was identified in three Kilkenny juveniles with bone collagen ¿13C above -17¿, and incremental dentine collagen demonstrating temporal changes in ¿13C consistent with dietary change from C3 to C4 plants. Bone collagen values for two Lukin Street individuals were consistent with high marine protein consumption. Techniques developed in this study to sample increments of dentine representing nine months or less of life have improved temporal resolution not only for migration events but also short-term dietary changes and physiological status during childhood. Combining epigraphic, osteological and archaeological evidence, individual ¿lifeways¿ have been constructed using isotope data and provide insights into the connection between health, diet and skeletal manifestations of deprivation during childhood and adolescence. New models are investigated for examining maternal and infant health using dentine collagen increments formed in utero and combining dentine and bone collagen values to explore the effects of nutritional stress on bone turnover. / Arts and Humanities Council. The British Federation of Women Graduates (the Eila Campbell scholarship). The British Association for Biological, Anthropology and Osteoarchaeology (the Jane Moore prize).
89

Re-establishment of Wild Bee Communities on Reclaimed Ohio Coal Mines

Lanterman, Jessie L. 11 December 2017 (has links)
No description available.
90

Organic residue analysis of Red Lustrous Wheelmade Ware vessels traded across the eastern Mediterranean during the Late Bronze Age

Steele, Valerie J. January 2008 (has links)
Red Lustrous Wheelmade Ware (RLWm ware) transport and storage vessels have been excavated from Late Bronze Age (LBA) sites across the eastern Mediterranean. These distinctive vessels were traded for the valuable commodity they contained so far unidentified. Seventy-three sherds (61 RLWm ware, 12 in local fabrics) and two visible residues were analysed for organic residues using standard lipid extraction techniques. Seven residues from a previous study were re-examined. Gas chromatography-mass spectrometry identified four materials - beeswax, bitumen, fat/oil and resin. Beeswax, found only in vessels from Hittite sites in Turkey, was probably used as a post-firing treatment. Fat/oil, present in some sherds from every site, represents the contents of the vessels and showed many of the characteristics of degraded plant oil. Two examples contained a plant sterol and three yielded ricinoleic acid, a biomarker for castor oil. Gas-chromatography compound-specific isotope ratio mass spectrometry of selected residues excluded dairy products, ruminant animal fats and fish oils as source materials for the fats/oils, while comparison with a small database of modern oils created during this study does not exclude plant oils. Selected samples analysed by high performance liquid chromatography-tandem mass spectrometry did not reveal wine residues. Data on the elemental composition of the fabric collected during another study was re-analysed and compared with data from a further published study, confirming the remarkable consistency of RLWm ware fabric. Volume calculations were also attempted to give an estimate of the capacity of the main vessel forms.

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