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A major advantage of satellite remote sensing is that the imagery acquired provides a synoptic view of the landscape. Thus, repeat coverage by the satellite on a regular basis permits the detection of changes in land‐cover over time. This study demonstrates the application of remote sensing technology to the monitoring of mining activities at the Athabasca Oil Sands region of Alberta, Canada. First, we describe the techniques used to match a time sequence of Landsat imagery, both spatially and spectrally, to ensure that the spectral changes through time are due to land‐cover variations. A series of spectral trajectories were then extracted to assess changes in land‐cover through time. Secondly, a land‐cover classification was produced from the baseline 1984 imagery and, using historic and future mine extents, the classification was analyzed to determine the proportion of each land‐cover type affected through development. Results of the analysis indicate that since 1984 there has been a larger reduction in mixedwood dense and broadleaf vegetation classes than mixedwood sparse or dense conifer stands in the area. Based on the delineations of mine‐site activity, the area of woodland and wetland habitat subject to development has increased from approximately 2,520 hectare (ha) in 1984 to 32,930 ha in 2005.  相似文献   
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ABSTRACT. This article focuses on the plight of the Jews in Turkey during the Second World War, with the intention of analysing specific historical events through the lenses of leading theories of nationalism. First we review recent developments in historiography that contribute the framework for understanding both the hermeneutical possibilities and limitations when addressing historical texts. Then we employ three theories of nationalism – the ethno‐symbolist, instrumentalist and social constructivist – as a means of analysing and interpreting the historical events of the Jewish predicament vis‐à‐vis the Republic of Turkey. We conclude by suggesting what impact our findings may have on the narratives from this time period, and the way in which we can understand narratives today.  相似文献   
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