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The palaeobiota from a middle to late Holocene succession in Tom Thumbs Lagoon, N.S.W., Australia, reflects a range of environmental conditions caused by sea-level changes and active estuarine sedimentation. At the base of the succession (~ ?0.4 m AHD) a thin bed, containing molluscs dated at 6.7 ka B.P. by radiocarbon and amino acid racemisation, and foraminifers is indicative of open estuarine conditions. From +0.35 m AHD towards the top of the sequence the charophyte Lamprothamnium succinctum occurs in subrecent deposits. This species is characterised here by statistical measurements, and new characters are described and illustrated. The charophytes record a drop in sea level and the establishment of a lower salinity artificial wetland. The investigation has also established that decalcification in charophytes can be related to acidification produced by the release of organic acids, aggravated after 1928 by anthropogenic pollution.  相似文献   
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ABSTRACT

Shelley’s “Letter to Maria Gisborne” is a playful improvisational verse epistle, widely praised for its urbanity and its display of the poet’s invention. The verses turn on a catalogue of the collection of odd scientific and mechanical objects that Shelley found scattered around him in the place he composed the letter, the Livorno workshop of Gisborne’s son, a young engineer who was building a new-model steamboat at the time (with Shelley’s financial and intellectual backing). In the context of that space, the poem reads as a response to competing notions of invention. For Shelley, the engineer’s workshop is an attractive alternative to the poet’s tower—which was uncomfortably close to a Grub Street garret. Verbal and visual images of poets’ and scientists’ workshops, from Hogarth and Mary Robinson, to Joseph Wright of Derby and Frankenstein, illustrate the tensions embodied in the physical location and poetic performance of Shelley’s celebrated “Letter.”  相似文献   
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As heritage research has engaged with a greater plurality of heritage practices, scale has emerged as an important concept in Heritage Studies, albeit relatively narrowly defined as hierarchical levels (household, local, national, etcetera). This paper argues for a definition of scale in heritage research that incorporates size (geographical scale), level (vertical scale) and relation (an understanding that scale is constituted through dynamic relationships in specific contexts). The paper utilises this definition of scale to analyse heritage designation first through consideration of changing World Heritage processes, and then through a case study of the world heritage designation of the Ningaloo Coast region in Western Australia. Three key findings are: both scale and heritage gain appeal because they are abstractions, and gain definition through the spatial politics of interrelationships within specific situations; the spatial politics of heritage designation comes into focus through attention to those configurations of size, level and relation that are invoked and enabled in heritage processes; and researchers choice to analyse or ignore particular scales and scalar politics are political decisions. Utilising scale as size, level and relation enables analyses that move beyond heritage to the spatial politics through which all heritage is constituted.  相似文献   
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During the archaeobotanical investigation of Scythian–Sarmatian period (Early Iron Age), pits with crop processing waste, discovered in the floodplain of Donets River, eastern Ukraine, and charred remains of cereal grains, dominated by broomcorn millet, were recorded. The grains from the pits were radiocarbon dated to the fifth to first century BC. Those pits are distant from any known contemporaneous settlement. The apparent disconnection of these pits from any local settlement suggests that (1) millet was brought from other locations by mobile groups, or (2) millet was cultivated locally by populations whose settlements have left no discernible archaeological trace. The analysis of molecular biomarkers preserved in palaeosols that are stratigraphically connected to the pits revealed high levels of miliacin, a molecule that can be preserved in ancient soils and sediments, and that is consistent with broomcorn millet (Panicum miliaceum). High levels in miliacin in soils stratigraphically connected to the pits are interpreted as the result of a large biomass of P. miliaceum produced at time of soil formation. Our biogeochemical results applied to a palaeosol thus attest to the in situ cultivation of crops dominated by the broomcorn millet during the early Iron Age in the floodplain of Donets River. Biochemical examination of soils and palaeosols can thus provide useful information on past dynamics of land-use by ancient population, especially when settlements or macrobotanical remains are absent.  相似文献   
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