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G. Di Maida et al. / Marine Environmental Research 87-88 (2013) 96e102 101

conﬁrms ﬁndings from an earlier study also conducted at multiple Sclafani for his help with the graphs. We also wish to acknowledge
locations, in which the maximum magnitude of difference was
about 70% (Giovannetti et al., 2008). the anonymous reviewers and the editor for their very helpful

Previous studies highlighted that substratum typologies may comments and fruitful suggestions, which greatly assisted us in
explain the observed variation in P. oceanica descriptors at a scale of
tens of kilometers (Balestri et al., 2003). Here, we show that this improving the manuscript.
source of variation is also potentially present at a smaller scale,
since different substratum typologies may occur within the same References
area. As a consequence, differences detected among meadows may
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P. oceanica has been selected among Mediterranean seagrasses Boudouresque, C.F., Jeudy de Grissac, A., 1983. L’herbier à Posidonia oceanica en
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