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The extent of the cold-water coral mounds in the modern ocean basins has been recently revealed by new state-of-the-art equipment. However, not much is known about their geological extent or development through time. In the facies model presented here seven different types of seabed substrate are distinguished, which may be used for reconstruction of fossil coral habitats. The studied substrates include: off-mound settings, (foram) sands, hardgrounds, dead coral debris, and substrates characterized by a variable density of living coral framework. Whereas sediment characteristics only provide a basis for distinguishing on- and off-mound habitats and the loci of most prolific coral growth, benthic foraminiferal assemblages are the key to identifying different mound substrates in more detail. Specific foraminiferal assemblages are distinguished that are characteristic of these specific environments. Assemblages from off-mound settings are dominated by (attached) epifaunal species such as Cibicides refulgens and Cibicides variabilis. The attached epibenthic species Discanomalina coronata is also common in off-mound sediments, but it is most abundant where hardgrounds have formed. In contrast, the settings with coral debris or living corals attract shallow infaunal species that are associated with more fine-grained soft sediments. The typical 'living coral assemblage' is composed of Cassidulina obtusa, Bulimina marginata, and Cassidulina laevigata. The abundance of these species shows an almost linear increase with the density of the living coral cover. The benthic foraminifera encountered from off-mound to top-mound settings appear to represent a gradient of decreasing current intensity and availability of suspended food particles, and increasing availability of organic matter associated with fine-grained sediment trapped in between coral framework.

Submarine canyons are dynamic sedimentary environments influenced by sediment transport, erosion and deposition. Gravity flows can scour and erode the canyon floor, thus redistributing sediment to distal locations. In addition, submarine canyons can act as sedimentary traps where sediment transported laterally across the continental shelf and slope is advected into. Hence, elevated sedimentation rates and high organic carbon content are often found in submarine canyons in comparison with the adjacent open slope. Such dynamic processes must affect the ecosystems inhabiting these exceptional environments. To investigate and quantify this relationship, living benthic foraminifera were sampled from Nazaré and Lisbon-Setbal submarine canyons located on the Portuguese continental margin. The foraminiferal abundances and species distribution were correlated with a host of geochemical (e.g. organic carbon, phytopigment content, redox chemistry) and physical/sedimentological parameters (e.g. current speed, sedimentation rate, frequency of gravity flows). Eventually this information was used to reconstruct temporal variations in sedimentation processes and associated changes in foraminiferal community structure in two piston cores derived from the lower canyon. The results of these studies highlight the importance of habitat instability and food abundance in structuring the foraminiferal communities in canyons. Food, quantified in terms of the sedimentary phytopigment content, was readily available in the studied canyons, declining in abundance with increasing water depth. Food abundance was also reflected in the pore water chemistry (nitrate penetration depth used as a redox indicator), higher pigment content coinciding with shallower nitrate penetration depth in sediment. The standing stocks of foraminifera and community structure changed with these parameters, and a positive correlation was observed between foraminiferal numbers and the sedimentary pigment content and a negative with the nitrate penetration depth. Stations recording the highest pigment loads (> 15g/cm3) and the shallowest redox zones (nitrate penetration depth

Submarine canyons are dynamic sedimentary environments influenced by sediment transport, erosion and deposition. Gravity flows can scour and erode the canyon floor, thus redistributing sediment to distal locations. In addition, submarine canyons can act as sedimentary traps where sediment transported laterally across the continental shelf and slope is advected into. Hence, elevated sedimentation rates and high organic carbon content are often found in submarine canyons in comparison with the adjacent open slope. Such dynamic processes must affect the ecosystems inhabiting these exceptional environments. To investigate and quantify this relationship, living benthic foraminifera were sampled from Nazaré and Lisbon-Setbal submarine canyons located on the Portuguese continental margin. The foraminiferal abundances and species distribution were correlated with a host of geochemical (e.g. organic carbon, phytopigment content, redox chemistry) and physical/sedimentological parameters (e.g. current speed, sedimentation rate, frequency of gravity flows). Eventually this information was used to reconstruct temporal variations in sedimentation processes and associated changes in foraminiferal community structure in two piston cores derived from the lower canyon. The results of these studies highlight the importance of habitat instability and food abundance in structuring the foraminiferal communities in canyons. Food, quantified in terms of the sedimentary phytopigment content, was readily available in the studied canyons, declining in abundance with increasing water depth. Food abundance was also reflected in the pore water chemistry (nitrate penetration depth used as a redox indicator), higher pigment content coinciding with shallower nitrate penetration depth in sediment. The standing stocks of foraminifera and community structure changed with these parameters, and a positive correlation was observed between foraminiferal numbers and the sedimentary pigment content and a negative with the nitrate penetration depth. Stations recording the highest pigment loads (> 15g/cm3) and the shallowest redox zones (nitrate penetration depth