The authors are deeply indebted to Dr H Mitwally, associate prof

The authors are deeply indebted to Dr H. Mitwally, associate professor of marine biology, Oceanography Department, Faculty of Science, Alexandria University, for help in the ANOVA analysis. “
“The widespread APO866 in vivo use of

multi-beam echosounders in scientific research permits the collection of complex information in a short time. Much work has been done in recent years in the Spitsbergen region using this technology, which has delivered very detailed maps as well as information on the area’s morphological characteristics (e.g. Ottesen and Dowdeswell, 2006, Ottesen and Dowdeswell, 2009, Ottesen et al., 2007, Ottesen et al., 2008, Forwick et al., 2009 and Dowdeswell et al., 2010). But such work requires the use of large vessels; this increases the costs of exploration and it also has its limitations. For reasons of safety, data recording is usually performed in

areas already covered by marine publications and charts (e.g.The Norwegian Hydrographic Service and Norwegian this website Polar Research 1990, United Kingdom Hydrographic Office 2007, Statens Kartverk 2008). It is often the case, however, that existing maps do not show areas from which glaciers have retreated and are insufficiently detailed (Pastusiak 2010). Small boats with a shallow draught then have to be employed, as they provide a safer working environment when sailing in unexplored areas. In such difficult measuring conditions it is usually only single-beam echosounders that can be used. Direct interpolation of the profiles obtained enables geographical regionalisation in that individual

bays, once influenced by glaciers, can be identified (Moskalik et al. 2013a) and their shapes characterised (Moskalik et al. 2013b). But again, these properties describe pre-glacial valleys in their entirety but not in fine detail. In the present work, the bathymetric profiles were analysed under the assumption that areal diversity is expressed by the diversity of regional profiles. Moreover, the density of depth measurements being far greater than that of the inter-profile distances, additional information can be obtained on the nature of the bottom forms. Brepollen, the region where this research was carried out, is the inner part of the Hornsund Fjord, which itself is the most southerly most fjord in western Spitsbergen (Figure 1a). Bathymetric data were collected from a small boat equipped with a low-cost Lowrance LMS-527cDF echosounder during the summers of 2007 and 2008. A total of 120 bathymetric sections with an overall length of 384 km were made (Figure 1c). An interpolated bathymetry map for Brepollen (Figure 1b) was prepared on a 25 m grid (Moskalik et al. 2013a). It was assumed that it showed all forms larger than ten times the size of the grid; forms smaller than 250 m therefore required detailed analysis.

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