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31.
Abstract

Observation of cause–effect patterns of change in coastal environments provides insights into vulnerable areas and supports prediction and adaptation to flooding and erosion. Historic and periodic (6–8 year intervals) imagery from the Landsat archive is used to investigate transformations in the Atlantic coast of two Scottish islands over the period 1989–2011. Supervised classification of spectrally normalized images followed by change detection and spatial analysis reveals the patterns of change and the location of the most dynamic coastal areas. Quantitative measures of recent shifts and movement rates of relevant coastal lines, such as the lower limit of land-based vegetation, are assessed with the Digital Shoreline Analysis System. While very low rates are indicated for horizontal changes in the position of the lower limit of land-based vegetation (0.3?m?y?1), specific areas have been subjected to high rates of coastal progradation as well as erosion (e.g. 2.5?m?y?1 at Stilligarry). Information derived from satellite data supports the characterization of geomorphologically dynamic coasts at regional scales. With a rich and open access archive of imagery, a commitment to continuity, and compatibility with the Earth observation missions of other space programs, the Landsat mission offers useful and otherwise unavailable data for monitoring of coastal areas.  相似文献   
32.
The Neolithic site Ri??ukalns in the Lake Burtnieks/River Salaca area in northern Latvia is the only freshwater shell midden in the eastern Baltic Sea area. An excavation carried out in 2011 revealed an intact stratigraphy with alternating layers of unburnt and burnt mussel shells and yielded various kinds of archaeological finds, among them several thousand fish remains. To gain an understanding of the fish species and specimens caught by the Neolithic settlers, and to discern any temporal development in the fish species composition, we analysed fish remains from different sections and layers. Results from both the archaeozoological and stable isotope data, give evidence for a change in the relevance of fish species during the period of use, and they also provide information for reconstructing the former river and lake hydrology in the vicinity of the midden. The Stone Age landscape seems to have been very similar to the present situation, so that the study area has been an extraordinarily stable ecosystem for more than 5000 years. Comparisons with the results of recent monitoring programmes, long-term changes since Medieval times, and written sources from the 18th century, show that the fish species community is almost unchanged since the Stone Age. This underlines the importance of the region in nature conservation.  相似文献   
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Politicians with presidential ambitions will often solicit asympathetic journalist to write a flattering biography as apreliminary for the campaign. Authorized biographies tell thelife story from the politicians’ perspective, highlightingtheir assets, ignoring their defects, and blaming their opponents.Usually based on interviews, they appear either as first person"as told to" autobiographies or as third-person narratives inwhich the biographer paraphrases and supplements material gleanedfrom the  相似文献   
34.
A new genus and species of lungfish with toothplates, Adelargo schultzei, is described from the Hunter Siltstone (Devonian, Late Famennian) near Grenfell, New South Wales. Materials assigned to Adelargo schultzei gen. et sp. nov., include a portion of the left side of the skull comprising B, I (postparietal) and J (parietal) bones, pterygoid and prearticular toothplates, a parasphenoid with a long posterior stalk, vertebrae, ribs, anal fin supports and scales. Toothplates are similar to Dipterus, although morphology of the skull, parasphenoid and postcranial elements is more derived. Biogeographic relationships of the Grenfell fauna were based on the presence of the antiarch group Sinolepidoidei, also present on Asian terranes during the Late Devonian. A small number of lungfish scales have been described from Asian sinolepid localities of this age, but differ from those of Adelargo schultzei, and other faunal similarities between these areas appear limited. Paucity of eastern Australian Devonian taxa on the North and South China blocks implies that strong biogeographic relationships between eastern Australia and Euramerican localities during the Late Devonian were not the result of Asian migration routes, but the closer proximity of these areas.  相似文献   
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The ischnacanthid acanthodian Grenfellacanthus zerinae gen. et sp. nov. is described on the basis of two large jaw bones from the Late Devonian (late Famennian) Hunter Formation, near Grenfell, N.S.W. The new species is the youngest known ischnacanthid, and the largest ischnacanthid from Gondwana. As for many ischnacanthids, the structure of the jaws and teeth indicate that Grenfellacanthus was probably an ambush predator.  相似文献   
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