Unique particulate organic carbon properties driven by turbidity currents

Turbidity currents are critical mechanisms for lateral transport of particulate organic carbon (POC) to the deep sea, yet sampling challenges have created substantial knowledge gaps regarding their impact on POC biogeochemistry. Here, a systematic comparison of turbidity current-driven particles (PS turb ), background sinking particles (PS sink ), and seafloor surface particles (PS surf ) via direct sampling revealed unique older, petrogenic, terrestrial POC features of PS turb in northern Manila Trench. The ~51±33-fold higher PS turb flux than PS sink suggested that turbidity currents efficiently redistributed POC, especially the petrogenic fraction derived from mountainous Taiwan. While global sediment trap POC data synthesis enabled Manila Window for regional diagnosis of turbidity-current influences using fraction of modern carbon Fm < 0.82 and total organic carbon content TOC < 1.62%, water-column particles affected by turbidity currents followed Manila Equation (Fm=0.7*TOC-0.08, R 2 =0.95, p<0.01). These results provide new insights regarding lateral POC transport processes and their importance when building global carbon cycle models.