Mixed Layer Depth Promotes Trophic Amplification on a Seasonal Scale

The Humboldt Upwelling System is of global interest due to its importance fisheries, though the origin high productivity remains elusive. In regional physical-biogeochemical model simulations, seasonal amplitude mesozooplankton net production exceeds that phytoplankton, indicating “seasonal trophic amplification.” An analytical approach identifies amplification be driven by a seasonally varying transfer efficiency mixed layer variations. latter alters vertical distribution phytoplankton and thus zooplankton encounters, with lower encounters occurring in deeper where are diluted. depth appears affect similarly other productive regions. Our results highlight for trophodynamics on scale potential significant implications, given changes projected under climate change.