Sink or swim: Accumulation of biomass at fronts

The dense concentrat~ons of blomass colnmonly seen at fronts are often explalned by a phys~olog~cal response of the oiganlsms to the frontal environment However, some fractlon of the enhanced b~omass may be explalned through purely phys~cal processes the interaction of floating sinking or swlmmlng w ~ t h the flows at a front To explore this hypothesis, I present a model of steady, 2-dlmenslonal cross-frontal circulat~ons, whlch I combine ~11 th a vanety of swlrnming behaviors The models show how patchmess may arise at fronts through retention and accumulat~on zones, and the patterns which evolve glven vanous flow and swimmlng characterlst~cs The ecological slgnlficance of the results 1s discussed

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