Abstract

Biweekly sediment trap samples were collected from the Santa Barbara Basin between August 1993 and April 2000. We compare the siliceous phytoplankton species from these traps with mixed-layer phytoplankton samples from quarterly cruises. We evaluate signals from the two data sets, without regard to their specific compositions. Both data sets indicate strong, regular spring blooms. The trap data allow definition of a fall-winter flora not identified from the water samples. The water samples allow definition of an oceanic warm-water flora, not readily seen in the trap data. Many of these differences are procedural artifacts. However, significant differences arise from the different scales of the samples. Species' relationships, which are often expressed over relatively short scales of time and space, are better captured by the small-scale water samples. Regional oceanographic and climatic signals are more efficiently captured in trap samples, which integrate over small-scale variability.