Identifying the dominant processes (physical versus biological) in pelagicmarine ecosystems from held estimates of chlorophyll a and phytoplankton production

A new approach is described to identify the dominant process (physical vers us biological) in a pelagic marine ecosystem, from simple biological oceano graphic field variables. The approach is based on quantification of the mat ching (M) between phytoplankton production (P) and losses, from held estima tes of chlorophyll a (Chl) and P. Coefficient Ail is estimated for a wide r ange of oceanic and coastal environments and of trophic characteristics, us ing data from the literature. Results show that M characterizes the dominan ce of physical versus biological processes in pelagic systems. The coeffici ent may be especially useful as a means for extracting process information on pelagic marine ecosystems from large data sets of Chi and P, e.g. record ed by moored instruments or provided by satellite images of ocean colour.