Definition: The mariine bathyal zone biome comprises regions of the marine benthic biome between approximately 200 m and 3000 m depth. This zone generally coincides with the continental slope.
Definition: The bathypelagic zone biome comprises the marine water column below approximately 1000 m water depth - the maximum depth to which detectable daylight penetrates in all but the clearest oligotrophic waters - and extends to about 2500 - 2700 m water depth. In the temperate Atlantic, the beginning of the bathypelagic zone biome approximates to the deep oxygen minimum and the base of the permanent thermocline.