“…Surface metrics are quantitative measures of continuous variables (McGarigal et al, 2009;Cushman et al, 2010). Environmental applications of surface metrics have occurred in mountainous regions (Nogami, 1995;Riley et al, 1999;Dorner et al, 2002;McGarigal et al, 2009;Iwahashi et al, 2012) or on the sea floor (McCormick, 1994;Brock et al, 2004;Wilson et al, 2007;Wedding et al, 2008;Walker et al, 2009;Zawada and Brock, 2009;Zawada et al, 2010;Friedman et al, 2012), with only limited applications in riverine settings (Everson and Boucher, 1998;Aberle et al, 2010;Legleiter, 2014b).…”