| The primary goal of this research was to determine the importance of bubble-extracted surface-active carbohydrates in particle aggregation during the course of marine algal blooms in a controlled mesocosm and at coastal sites.;Surface-active polysaccharides fell into two categories: a 'highly' surface-active fraction that was mainly extracted at the beginning of the bubbling period, and a 'less' surface-active fraction which was extracted at a low, uniform rate over the bubbling period. The 'highly' surface-active fraction was enriched in deoxysugars (fucose and rhamnose), galactose, and sulfate half-esters. The composition of the 'less' surface-active fraction was more variable.;The concentration of surface-active carbohydrates (chlorophyll normalized) was strongly correlated with the stickiness of particles in the mesocosm. Thus, particle stickiness appeared to be controlled by algal release of highly surface-active carbohydrates. In the East Sound study, the correlation between surface-active carbohydrates and particle stickiness was either non-existent or even negative, perhaps due to low exopolysaccharide production, as the bloom was only in early log growth phase.;Non-living background particles (;Size fractionation studies showed that colloidal materials (... |
