A novel method to study the fragmentation behavior of marine snow aggregates in controlled shear flow

The sinking of marine aggregates impacts the global carbon cycle as it is one primary sources export from surface ocean. Aggregation and fragmentation alter size aggregates, which governs their speed. Although aggregation theory well established, aggregate strength breakup characteristics are less understood. This study developed a cylindrical tank that formed then exposed diatom to calibrated laminar shear through combined rotating oscillating motion. rate was predictable using analytical solution for fluid motion within tank. Under proper operating conditions, this facility provided with similar magnitude in multiple ocean environments. We also unique image processing method enabled continuous tracking particles' position, size, morphology determination individual events. has great potential capture events large snow particles, quantify morphological changes leading up at breakup, provide data sufficient statistical analysis laboratory populations. tested laboratory-cultured Odontella aurita captured 79 resulting aggregates. These fragmented ranged 1 5 mm major axis length underwent substantial evolutions prior fragmentation.