Long-Term Discrepancy Between Food Supply and Demand in the Deep Eastern North Pacific

Abstract

A 7-year study of food supply [sinking particulate organic carbon (POC)] and food demand [sediment community oxygen consumption (SCOC)] in the abyssal eastern North Pacific revealed a long-term deficit in food supply. The POC:SCOC ratio decreased by 52 to 59 percent between 1989 and 1996. A possible explanation for this trend is the documented sea surface temperature increase and concomitant plankton biomass decrease in the eastern North Pacific, resulting in an apparent reduction in POC export from surface waters to the deep ocean. Continuation of this trend could profoundly impact geochemical cycling as well as the structure and dynamics of deep-sea communities.