A nacreous sea salp is a barrel-shaped, planktic tunicate. Being a filtered feeder, it also moves by contracting, thus pumping water through its gelatinous body. Nacreous sea salp usually lives in long stringy colonies.
Drawn into a specific extreme environment where their habitat is full of marine microplastic particles (MPP), while absorbing nutrition by filtering water, MPP will accumulate in the mantle lumen of nacreous sea salps.
When reaching a certain stage that the sediment particles in the lumen are so weighty that they can’t continue swimming or wandering in water anymore, the sea salp colonies start the asexual reproduction process that they bud off clones.
After reproduction a special mechanism of nacreous rigidification happens in the lumen of the older generation that their slimy transparent guts become solid and dense. Subsequently, the older generation come off from the colonies and sink to the seafloor, where they accumulate in the sediment and slowly build up a ‘seawall.’ This physiological mechanism can be seen as a critical way of microplastics sequestration.
