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Archaeology, hydrogeology and geomythology in the Stymphalos Valley
No full textThis paper uses the results of recent excavations of the city of Stymphalos and environmental studies on the floor of the Stymphalos polje to examine the role of both the lake and springs in the history of the classical city. Associated with Artemis and famed for Herakles’ sixth labour (killing of the Stymphalian birds) the city has a rich mythology. Whilst this narrative has been associated solely with the lake, it is argued here that this geomythology was part of the city’s relationship to environmental unpredictability and the relationship between water supply and water loss. Seen in this context, the construction of the Fountain-house well above the contemporary lake-shore is symbolic of the importance of springs to the foundation and sustainability of the classical city during both the Greek and Roman Periods. Through these archaeological and environmental analyses, we seek to illustrate the complimentary, but complex nature of archaeological, hydrogeological and palaeoenvironmental data that intersect in the geomythological landscapes of Mediterranean antiquity
Modelling vegetation cover and wetland expansion in the Lower Thames Valley, UK: Multi-proxy records from Littlebrook Power Station, Kent
No full textThe interaction of ‘natural’ environmental processes and human activity in shaping landscapes is vividly illustrated in the Lower Thames Valley, UK. Through development-led (geo)archaeological investigations, intensifying redevelopment of this (currently) industrial landscape presents opportunities to gain long-term perspectives on these processes and to investigate the timing and extent of human impact on the environment in the past. This paper describes a novel multi-method approach undertaken at the former Littlebrook Power Station, Kent, comprising landscape-scale deposit modelling, multi-proxy palaeo-environmental analysis and vegetation cover reconstruction using REVEALS to produce schematic landscape reconstruction maps. Micropaleontological data reveal variable estuarine/freshwater influence, which alongside longer-term trends towards rising relative sea level drove lateral expansion of wetlands through the Holocene. Pollen-derived vegetation models show Early Holocene dense forest cover reduced to ∼55 per cent by 7–8 kyr BP followed by a step-change to grassland dominance in the early Bronze Age. Since grassland expansion was not proportionate to modelled expansion of wetlands but was associated with increased pastoral indicators, an anthropogenic cause of the deforestation in the Bronze Age is probable. This paper highlights the value of combining geoarchaeological data with novel modelling approaches to visualise ancient landscapes and thereby offer long-term perspectives on landscape-scale human-environment interactions
Modelling prehistoric topography and vegetation in the lower Thames Valley, UK: Palaeoenvironmental context for wetland archaeology and evidence for Neolithic Landnám from north Woolwich
No full textMulti-proxy investigations at 2 Pier Road, North Woolwich, London, UK, have revealed deposits spanning the Middle-Late Holocene from the late Mesolithic (c. 4360 cal BC) onwards. Pollen data show an Elm Decline at c. 4210–3950 cal BC followed by landnám clearances at c. 4210–3910 cal BC and c. 3710–3030 cal BC and the first appearance of cereal at c. 3540–3030 cal BC. These events are potentially contemporary with the construction of nearby Neolithic trackways, providing indirect evidence for agriculture and settlement. REVEALS modelling shows the first significant reduction in woodland cover is coincident with the Neolithic Elm decline, but the main step-change to open conditions occurred in the Early Bronze Age, following a decline in lime at c. 2110–1630 cal BC. Palaeo-topographic modelling of the region shows that although the trend towards increasing openness coincides with gradual wetland expansion, the shift to open vegetation cover cannot be explained by this and is probably the result of human activity. This study highlights the value of combining deposit and vegetation cover modelling to contextualise wetland archaeology and shows that together these provide useful proxies for landscape-scale human activity that can identify ephemeral signals of prehistoric activity.</p
A late glacial-Holocene record of Southern Hemisphere westerly wind dynamics from the Falkland Islands, South Atlantic
No full textThe Southern Hemisphere westerly wind belt (SHWW) is a major feature of Southern Hemisphere, midlatitude climate that is closely linked with the sequestration and release of CO2 in the Southern Ocean. Past changes in the strength and position of this wind belt are poorly resolved, particularly across the Pleistocene-Holocene transition, a time period associated with fluctuations in atmospheric temperatures and CO2 levels. We used dust geochemistry, particle size measurements, and paleoecological analyses from a peat sequence in the Falkland Islands, South Atlantic Ocean, to describe changes in the SHWW between 16.0 and 6.5 ka (thousands of years before CE 1950). Wind strength was low at ~51°S before and during the Antarctic Cold Reversal (ACR, 14.9–13.0 ka), intensified between 13.1 and 12.1 ka as atmospheric temperatures increased, and then weakened, reaching a minimum between 12.1 and 10.9 ka during the Early Holocene thermal maximum. Northwesterly air masses became more dominant from 12.0 to 10.2 ka, and wind strength remained low until our record was affected by a storm surge or tsunami ca. 7.8 ka. These data indicate a southward shift in the latitude of the SHWW, from north of 51°S prior to and during the ACR, at ~51°S before the onset of the Holocene, and south of 51°S during the early Holocene thermal maximum. This pattern suggests that the latitude of the SHWW was coupled with atmospheric temperatures through the Pleistocene-Holocene transition
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Lateglacial/early holocene palaeoenvironments in the southern north sea basin: new data from the Dudgeon offshore wind farm
No full textIt is well known that the North Sea conceals an extensive former landscape of Late Pleistocene and Holocene date that was progressively submerged as result of rising post‐glacial sea levels. Although an increasingly detailed picture is emerging of these submerged palaeolandscapes, well‐dated palaeoenvironmental reconstructions from the North Sea Basin remain few and far between. Pollen, foraminifera, ostracod, plant macrofossil and molluscan data are presented from a radiocarbon‐dated core retrieved from the site of the Dudgeon offshore wind farm, located in the southern North Sea Basin. The palaeoenvironmental analysis provides new data on changing local physical and vegetation environments in the southern North Sea Basin, occurring against a background of global climate change and rising sea levels. Subalpine plant communities gradually gave way to hazel‐dominated woodland during the early Holocene, with freshwater environments replaced by increasing signs of estuarine influence from ca. 9500 to 9000 cal a BP. The thin upper peat (8411–8331 cal a BP) raises the possibility that the final inundation of the Dudgeon site may be linked to meltwater pulses following the collapse of the Laurentide Ice Sheet and the draining of the proglacial Lakes Agassiz and Ojibway
Liberating the Once Carefree Wanderer: the River Tyburn at the Curtis Green Building, Victoria Embankment, Westminster
No full textGoing Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
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