02125nas a2200289   4500000000100000008004100001653001700042653003600059653003300095653002700128100002200155700001400177700001600191700001500207700001600222700001300238700001500251700001500266700001400281700001400295700001200309700001500321245011700336856006100453490000800514520131300522       2023                            d10aGravity flow10ainterplay flow-sediment-biology10asubaqueous channel evolution10asubmarine channel bend1 aM. Azpiroz-Zabala1 aE. Sumner1 aM. Cartigny1 aJ. Peakall1 aM.~A. Clare1 aS. Darby1 aD. Parsons1 aR. Dorrell1 aE. Özsoy1 aD. Tezcan1 aR. Wynn1 aJ. Johnson00aBenthic biology influences sedimentation in submarine channel bends: Coupling of biology, sedimentation and flow  uhttps://onlinelibrary.wiley.com/doi/abs/10.1002/dep2.2650 vn/a3 aAbstract Submarine channels are key features for the transport of flow and nutrients into deep water. Previous studies of their morphology and channel evolution have treated these systems as abiotic, and therefore assume that physical processes are solely responsible for morphological development. Here, a unique dataset is utilised that includes spatial measurements around a channel bend that hosts active sediment gravity flows. The data include flow velocity and density, alongside bed grain size and channel-floor benthic macrofauna. Analysis of these parameters demonstrate that while physical processes control the broadest scale variations in sedimentation around and across the channel, benthic biology plays a critical role in stabilising sediment and trapping fines. This leads to much broader mixed grain sizes than would be expected from purely abiotic sedimentation, and the maintenance of sediment beds in positions where all the sediment should be actively migrating. Given that previous work has also shown that submarine channels can be biological hotspots, then the present study suggests that benthic biology probably plays a key role in channel morphology and evolution, and that these need to be considered both in the modern and when considering examples preserved in the rock record.