Towards a new and integrated approach to submarine canyon research. Introduction

Submarine canyons, steep-walled valleys that cut across virtually every continental margin around the world (Harris and Whiteway, 2011), are considered major sediment transport pathways between continental shelves and the deep sea (e.g., Shepard, 1963 and Puig et al., 2014). Owing to their steep topography and high terrain heterogeneity, in addition to their unique current patterns and episodic down-canyon flushing events, which result in locally increased nutrient concentrations and food availability, submarine canyons are often considered as biodiversity hotspots (e.g., Tyler et al., 2009 and De Leo et al., 2010). On the other hand, considerable differences have been observed between individual canyon systems, and between different faunal groups in terms of their response to the typical canyon environment (e.g., Cunha et al., 2011, Ingels et al., 2011 and Schlacher et al., 2007). Unfortunately, in addition to transporting sediment, submarine canyons also tend to funnel our human litter and pollutants into the deep sea, extending the anthropogenic impact on the oceans far beyond our shores (e.g., de de Jesus Mendes et al., 2011, Mordecai et al., 2011 and Schlining et al., 2013).